This involves converting migrate_huge_page_move_mapping(). We also need a
folio variant of hugetlb_set_page_subpool(), but that's for a later patch.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
There is nothing iomap-specific about iomap_migratepage(), and it fits
a pattern used by several other filesystems, so move it to mm/migrate.c,
convert it to be filemap_migrate_folio() and convert the iomap filesystems
to use it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Convert all callers to pass a folio. Most have the folio
already available. Switch all users from aops->migratepage to
aops->migrate_folio. Also turn the documentation into kerneldoc.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Now that both callers have a folio, convert this function to
take a folio & rename it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Use a folio throughout __buffer_migrate_folio(), add kernel-doc for
buffer_migrate_folio() and buffer_migrate_folio_norefs(), move their
declarations to buffer.h and switch all filesystems that have wired
them up.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Use a folio throughout. migrate_page() will be converted to
migrate_folio() later.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Provide a folio-based replacement for aops->migratepage. Update the
documentation to document migrate_folio instead of migratepage.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
These drivers are rather uncomfortably hammered into the
address_space_operations hole. They aren't filesystems and don't behave
like filesystems. They just need their own movable_operations structure,
which we can point to directly from page->mapping.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
The isolate_page operation is never called for filesystems, only
for device drivers which call SetPageMovable.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
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Merge tag 'slab-for-5.20_or_6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab updates from Vlastimil Babka:
- An addition of 'accounted' flag to slab allocation tracepoints to
indicate memcg_kmem accounting, by Vasily
- An optimization of memcg handling in freeing paths, by Muchun
- Various smaller fixes and cleanups
* tag 'slab-for-5.20_or_6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab_common: move generic bulk alloc/free functions to SLOB
mm/sl[au]b: use own bulk free function when bulk alloc failed
mm: slab: optimize memcg_slab_free_hook()
mm/tracing: add 'accounted' entry into output of allocation tracepoints
tools/vm/slabinfo: Handle files in debugfs
mm/slub: Simplify __kmem_cache_alias()
mm, slab: fix bad alignments
- Remove unused generic cpuidle support (replaced by PSCI version)
- Fix documentation describing the kernel virtual address space
- Handling of some new CPU errata in Arm implementations
- Rework of our exception table code in preparation for handling
machine checks (i.e. RAS errors) more gracefully
- Switch over to the generic implementation of ioremap()
- Fix lockdep tracking in NMI context
- Instrument our memory barrier macros for KCSAN
- Rework of the kPTI G->nG page-table repainting so that the MMU remains
enabled and the boot time is no longer slowed to a crawl for systems
which require the late remapping
- Enable support for direct swapping of 2MiB transparent huge-pages on
systems without MTE
- Fix handling of MTE tags with allocating new pages with HW KASAN
- Expose the SMIDR register to userspace via sysfs
- Continued rework of the stack unwinder, particularly improving the
behaviour under KASAN
- More repainting of our system register definitions to match the
architectural terminology
- Improvements to the layout of the vDSO objects
- Support for allocating additional bits of HWCAP2 and exposing
FEAT_EBF16 to userspace on CPUs that support it
- Considerable rework and optimisation of our early boot code to reduce
the need for cache maintenance and avoid jumping in and out of the
kernel when handling relocation under KASLR
- Support for disabling SVE and SME support on the kernel command-line
- Support for the Hisilicon HNS3 PMU
- Miscellanous cleanups, trivial updates and minor fixes
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Highlights include a major rework of our kPTI page-table rewriting
code (which makes it both more maintainable and considerably faster in
the cases where it is required) as well as significant changes to our
early boot code to reduce the need for data cache maintenance and
greatly simplify the KASLR relocation dance.
Summary:
- Remove unused generic cpuidle support (replaced by PSCI version)
- Fix documentation describing the kernel virtual address space
- Handling of some new CPU errata in Arm implementations
- Rework of our exception table code in preparation for handling
machine checks (i.e. RAS errors) more gracefully
- Switch over to the generic implementation of ioremap()
- Fix lockdep tracking in NMI context
- Instrument our memory barrier macros for KCSAN
- Rework of the kPTI G->nG page-table repainting so that the MMU
remains enabled and the boot time is no longer slowed to a crawl
for systems which require the late remapping
- Enable support for direct swapping of 2MiB transparent huge-pages
on systems without MTE
- Fix handling of MTE tags with allocating new pages with HW KASAN
- Expose the SMIDR register to userspace via sysfs
- Continued rework of the stack unwinder, particularly improving the
behaviour under KASAN
- More repainting of our system register definitions to match the
architectural terminology
- Improvements to the layout of the vDSO objects
- Support for allocating additional bits of HWCAP2 and exposing
FEAT_EBF16 to userspace on CPUs that support it
- Considerable rework and optimisation of our early boot code to
reduce the need for cache maintenance and avoid jumping in and out
of the kernel when handling relocation under KASLR
- Support for disabling SVE and SME support on the kernel
command-line
- Support for the Hisilicon HNS3 PMU
- Miscellanous cleanups, trivial updates and minor fixes"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (136 commits)
arm64: Delay initialisation of cpuinfo_arm64::reg_{zcr,smcr}
arm64: fix KASAN_INLINE
arm64/hwcap: Support FEAT_EBF16
arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
arm64/hwcap: Document allocation of upper bits of AT_HWCAP
arm64: enable THP_SWAP for arm64
arm64/mm: use GENMASK_ULL for TTBR_BADDR_MASK_52
arm64: errata: Remove AES hwcap for COMPAT tasks
arm64: numa: Don't check node against MAX_NUMNODES
drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX
perf: RISC-V: Add of_node_put() when breaking out of for_each_of_cpu_node()
docs: perf: Include hns3-pmu.rst in toctree to fix 'htmldocs' WARNING
arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"
mm: kasan: Skip page unpoisoning only if __GFP_SKIP_KASAN_UNPOISON
mm: kasan: Skip unpoisoning of user pages
mm: kasan: Ensure the tags are visible before the tag in page->flags
drivers/perf: hisi: add driver for HNS3 PMU
drivers/perf: hisi: Add description for HNS3 PMU driver
drivers/perf: riscv_pmu_sbi: perf format
perf/arm-cci: Use the bitmap API to allocate bitmaps
...
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Merge tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Two hotfixes, both cc:stable"
* tag 'mm-hotfixes-stable-2022-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/hmm: fault non-owner device private entries
page_alloc: fix invalid watermark check on a negative value
Fixes a typo in the help section for ZSWAP.
Link: https://lkml.kernel.org/r/Message-ID:
Signed-off-by: Sophia Gabriella <sophia.gabriellla@outlook.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use pr_fmt to prefix all pr_<level> output, but unpoison_memory() and
soft_offline_page() are used by error injection, which have own prefixes
like "Unpoison:" and "soft offline:", meanwhile, soft_offline_page() could
be used by memory hotremove, so reset pr_fmt before unpoison_pr_info
definition to keep the original output for them.
[wangkefeng.wang@huawei.com: v3]
Link: https://lkml.kernel.org/r/20220729031919.72331-1-wangkefeng.wang@huawei.com
Link: https://lkml.kernel.org/r/20220726081046.10742-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use is_zone_movable_page() helper to simplify code.
Link: https://lkml.kernel.org/r/20220726131135.146912-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/mprotect: Fix soft-dirty checks", v4.
This patch (of 3):
The check wanted to make sure when soft-dirty tracking is enabled we won't
grant write bit by accident, as a page fault is needed for dirty tracking.
The intention is correct but we didn't check it right because
VM_SOFTDIRTY set actually means soft-dirty tracking disabled. Fix it.
There's another thing tricky about soft-dirty is that, we can't check the
vma flag !(vma_flags & VM_SOFTDIRTY) directly but only check it after we
checked CONFIG_MEM_SOFT_DIRTY because otherwise VM_SOFTDIRTY will be
defined as zero, and !(vma_flags & VM_SOFTDIRTY) will constantly return
true. To avoid misuse, introduce a helper for checking whether vma has
soft-dirty tracking enabled.
We can easily verify this with any exclusive anonymous page, like program
below:
=======8<======
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <assert.h>
#include <inttypes.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdbool.h>
#define BIT_ULL(nr) (1ULL << (nr))
#define PM_SOFT_DIRTY BIT_ULL(55)
unsigned int psize;
char *page;
uint64_t pagemap_read_vaddr(int fd, void *vaddr)
{
uint64_t value;
int ret;
ret = pread(fd, &value, sizeof(uint64_t),
((uint64_t)vaddr >> 12) * sizeof(uint64_t));
assert(ret == sizeof(uint64_t));
return value;
}
void clear_refs_write(void)
{
int fd = open("/proc/self/clear_refs", O_RDWR);
assert(fd >= 0);
write(fd, "4", 2);
close(fd);
}
#define check_soft_dirty(str, expect) do { \
bool dirty = pagemap_read_vaddr(fd, page) & PM_SOFT_DIRTY; \
if (dirty != expect) { \
printf("ERROR: %s, soft-dirty=%d (expect: %d)
", str, dirty, expect); \
exit(-1); \
} \
} while (0)
int main(void)
{
int fd = open("/proc/self/pagemap", O_RDONLY);
assert(fd >= 0);
psize = getpagesize();
page = mmap(NULL, psize, PROT_READ|PROT_WRITE,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
assert(page != MAP_FAILED);
*page = 1;
check_soft_dirty("Just faulted in page", 1);
clear_refs_write();
check_soft_dirty("Clear_refs written", 0);
mprotect(page, psize, PROT_READ);
check_soft_dirty("Marked RO", 0);
mprotect(page, psize, PROT_READ|PROT_WRITE);
check_soft_dirty("Marked RW", 0);
*page = 2;
check_soft_dirty("Wrote page again", 1);
munmap(page, psize);
close(fd);
printf("Test passed.
");
return 0;
}
=======8<======
Here we attach a Fixes to commit 64fe24a3e0 only for easy tracking, as
this patch won't apply to a tree before that point. However the commit
wasn't the source of problem, but instead 64e455079e. It's just that
after 64fe24a3e0 anonymous memory will also suffer from this problem
with mprotect().
Link: https://lkml.kernel.org/r/20220725142048.30450-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20220725142048.30450-2-peterx@redhat.com
Fixes: 64e455079e ("mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared")
Fixes: 64fe24a3e0 ("mm/mprotect: try avoiding write faults for exclusive anonymous pages when changing protection")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
syzbot is reporting GFP_KERNEL allocation with oom_lock held when
reporting memcg OOM [1]. If this allocation triggers the global OOM
situation then the system can livelock because the GFP_KERNEL
allocation with oom_lock held cannot trigger the global OOM killer
because __alloc_pages_may_oom() fails to hold oom_lock.
Fix this problem by removing the allocation from memory_stat_format()
completely, and pass static buffer when calling from memcg OOM path.
Note that the caller holding filesystem lock was the trigger for syzbot
to report this locking dependency. Doing GFP_KERNEL allocation with
filesystem lock held can deadlock the system even without involving OOM
situation.
Link: https://syzkaller.appspot.com/bug?extid=2d2aeadc6ce1e1f11d45 [1]
Link: https://lkml.kernel.org/r/86afb39f-8c65-bec2-6cfc-c5e3cd600c0b@I-love.SAKURA.ne.jp
Fixes: c8713d0b23 ("mm: memcontrol: dump memory.stat during cgroup OOM")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+2d2aeadc6ce1e1f11d45@syzkaller.appspotmail.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit b05a79d437 ("mm/gup: migrate device coherent pages when pinning
instead of failing") added a badly formatted if statement. Fix it.
Link: https://lkml.kernel.org/r/20220721020552.1397598-2-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove the redundant updating of stats_flush_threshold. If the global var
stats_flush_threshold has exceeded the trigger value for
__mem_cgroup_flush_stats, further increment is unnecessary.
Apply the patch and test the pts/hackbench-1.0.0 Count:4 (160 threads).
Score gain: 1.95x
Reduce CPU cycles in __mod_memcg_lruvec_state (44.88% -> 0.12%)
CPU: ICX 8380 x 2 sockets
Core number: 40 x 2 physical cores
Benchmark: pts/hackbench-1.0.0 Count:4 (160 threads)
Link: https://lkml.kernel.org/r/20220722164949.47760-1-jiebin.sun@intel.com
Signed-off-by: Jiebin Sun <jiebin.sun@intel.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Amadeusz Sawiski <amadeuszx.slawinski@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We forget to set cft->private for numa stat file. As a result, numa stat
of hstates[0] is always showed for all hstates. Encode the hstates index
into cft->private to fix this issue.
Link: https://lkml.kernel.org/r/20220723073804.53035-1-linmiaohe@huawei.com
Fixes: f477619990 ("hugetlb: add hugetlb.*.numa_stat file")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Avoids truncating the debugfs output to 16 chars. Potentially alters
the userspace output, but this is a debugfs interface and there are no
stability guarantees.
Link: https://lkml.kernel.org/r/20220719091554.27864-1-quic_yingangl@quicinc.com
Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We can use unlock label to unlock ptl and return ret directly to remove
the unneeded out label and reduce the size of mempolicy.o. No functional
change intended.
[Before]
text data bss dec hex filename
26702 3972 6168 36842 8fea mm/mempolicy.o
[After]
text data bss dec hex filename
26662 3972 6168 36802 8fc2 mm/mempolicy.o
Link: https://lkml.kernel.org/r/20220719115233.6706-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
cpuset.c was moved to kernel/cgroup/ in below commit
201af4c0fa ("cgroup: move cgroup files under kernel/cgroup/")
Correct the wrong path in comment.
Link: https://lkml.kernel.org/r/20220718120336.5145-1-mark-pk.tsai@mediatek.com
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When code reaches here, the page must be !PageAnon. There's no need to
check PageAnon again. Remove it.
Link: https://lkml.kernel.org/r/20220716081816.10752-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This allows userspace to set flags like FS_APPEND_FL, FS_IMMUTABLE_FL,
FS_NODUMP_FL, etc., like all other standard Linux file systems.
[akpm@linux-foundation.org: fix CONFIG_TMPFS_XATTR=n warnings]
Link: https://lkml.kernel.org/r/20220715015912.2560575-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
damon_reclaim_init() allocates a memory chunk for ctx with
damon_new_ctx(). When damon_select_ops() fails, ctx is not released,
which will lead to a memory leak.
We should release the ctx with damon_destroy_ctx() when damon_select_ops()
fails to fix the memory leak.
Link: https://lkml.kernel.org/r/20220714063746.2343549-1-niejianglei2021@163.com
Fixes: 4d69c34578 ("mm/damon/reclaim: use damon_select_ops() instead of damon_{v,p}a_set_operations()")
Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
memory.reclaim is a cgroup v2 interface that allows users to proactively
reclaim memory from a memcg, without real memory pressure. Reclaim
operations invoke vmpressure, which is used: (a) To notify userspace of
reclaim efficiency in cgroup v1, and (b) As a signal for a memcg being
under memory pressure for networking (see
mem_cgroup_under_socket_pressure()).
For (a), vmpressure notifications in v1 are not affected by this change
since memory.reclaim is a v2 feature.
For (b), the effects of the vmpressure signal (according to Shakeel [1])
are as follows:
1. Reducing send and receive buffers of the current socket.
2. May drop packets on the rx path.
3. May throttle current thread on the tx path.
Since proactive reclaim is invoked directly by userspace, not by memory
pressure, it makes sense not to throttle networking. Hence, this change
makes sure that proactive reclaim caused by memory.reclaim does not
trigger vmpressure.
[1] https://lore.kernel.org/lkml/CALvZod68WdrXEmBpOkadhB5GPYmCXaDZzXH=yyGOCAjFRn4NDQ@mail.gmail.com/
[yosryahmed@google.com: update documentation]
Link: https://lkml.kernel.org/r/20220721173015.2643248-1-yosryahmed@google.com
Link: https://lkml.kernel.org/r/20220714064918.2576464-1-yosryahmed@google.com
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
zs_malloc returns 0 if it fails. zs_zpool_malloc will return -1 when
zs_malloc return 0. But -1 makes the return value unclear.
For example, when zswap_frontswap_store calls zs_malloc through
zs_zpool_malloc, it will return -1 to its caller. The other return value
is -EINVAL, -ENODEV or something else.
This commit changes zs_malloc to return ERR_PTR on failure. It didn't
just let zs_zpool_malloc return -ENOMEM becaue zs_malloc has two types of
failure:
- size is not OK return -EINVAL
- memory alloc fail return -ENOMEM.
Link: https://lkml.kernel.org/r/20220714080757.12161-1-teawater@gmail.com
Signed-off-by: Hui Zhu <teawater@antgroup.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In a system(Huawei Ascend ARM64 SoC) using HBM, a multi-bit ECC error
occurs, and the BIOS will mark the corresponding area (for example, 2 MB)
as unusable. When the system restarts next time, these areas are not
reported or reported as EFI_UNUSABLE_MEMORY. Both cases lead to an
increase in the number of memblocks, whereas EFI_UNUSABLE_MEMORY leads to
a larger number of memblocks.
For example, if the EFI_UNUSABLE_MEMORY type is reported:
...
memory[0x92] [0x0000200834a00000-0x0000200835bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0
memory[0x93] [0x0000200835c00000-0x0000200835dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4
memory[0x94] [0x0000200835e00000-0x00002008367fffff], 0x0000000000a00000 bytes on node 7 flags: 0x0
memory[0x95] [0x0000200836800000-0x00002008369fffff], 0x0000000000200000 bytes on node 7 flags: 0x4
memory[0x96] [0x0000200836a00000-0x0000200837bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0
memory[0x97] [0x0000200837c00000-0x0000200837dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4
memory[0x98] [0x0000200837e00000-0x000020087fffffff], 0x0000000048200000 bytes on node 7 flags: 0x0
memory[0x99] [0x0000200880000000-0x0000200bcfffffff], 0x0000000350000000 bytes on node 6 flags: 0x0
memory[0x9a] [0x0000200bd0000000-0x0000200bd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4
memory[0x9b] [0x0000200bd0200000-0x0000200bd07fffff], 0x0000000000600000 bytes on node 6 flags: 0x0
memory[0x9c] [0x0000200bd0800000-0x0000200bd09fffff], 0x0000000000200000 bytes on node 6 flags: 0x4
memory[0x9d] [0x0000200bd0a00000-0x0000200fcfffffff], 0x00000003ff600000 bytes on node 6 flags: 0x0
memory[0x9e] [0x0000200fd0000000-0x0000200fd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4
memory[0x9f] [0x0000200fd0200000-0x0000200fffffffff], 0x000000002fe00000 bytes on node 6 flags: 0x0
...
The EFI memory map is parsed to construct the memblock arrays before the
memblock arrays can be resized. As the result, memory regions beyond
INIT_MEMBLOCK_REGIONS are lost.
Add a new macro INIT_MEMBLOCK_MEMORY_REGIONS to replace
INIT_MEMBLOCK_REGTIONS to define the size of the static memblock.memory
array.
Allow overriding memblock.memory array size with architecture defined
INIT_MEMBLOCK_MEMORY_REGIONS and make arm64 to set
INIT_MEMBLOCK_MEMORY_REGIONS to 1024 when CONFIG_EFI is enabled.
Link: https://lkml.kernel.org/r/20220615102742.96450-1-zhouguanghui1@huawei.com
Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Darren Hart <darren@os.amperecomputing.com>
Acked-by: Will Deacon <will@kernel.org> [arm64]
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Xu Qiang <xuqiang36@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit 7267ec008b ("mm: postpone page table allocation until we
have page to map"), do_fault_around is not called with page table lock
held. Cleanup the corresponding comments.
Link: https://lkml.kernel.org/r/20220716080359.38791-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The number of scanned pages can be lower than the number of isolated pages
when isolating mirgratable or free pageblock. The metric is being
reported in trace event and also used in vmstat.
some example output from trace where it shows nr_taken can be greater
than nr_scanned:
Produced by kernel v5.19-rc6
kcompactd0-42 [001] ..... 1210.268022: mm_compaction_isolate_migratepages: range=(0x107ae4 ~ 0x107c00) nr_scanned=265 nr_taken=255
[...]
kcompactd0-42 [001] ..... 1210.268382: mm_compaction_isolate_freepages: range=(0x215800 ~ 0x215a00) nr_scanned=13 nr_taken=128
kcompactd0-42 [001] ..... 1210.268383: mm_compaction_isolate_freepages: range=(0x215600 ~ 0x215680) nr_scanned=1 nr_taken=128
mm_compaction_isolate_migratepages does not seem to have this
behaviour, but for the reason of consistency, nr_scanned should also be
taken care of in that side.
This behaviour is confusing since currently the count for isolated pages
takes account of compound page but not for the case of scanned pages. And
given that the number of isolated pages(nr_taken) reported in
mm_compaction_isolate_template trace event is on a single-page basis, the
ambiguity when reporting the number of scanned pages can be removed by
also including compound page count.
Link: https://lkml.kernel.org/r/20220711202806.22296-1-william.lam@bytedance.com
Signed-off-by: William Lam <william.lam@bytedance.com>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Yafang Shao reported an issue related to the accounting of bpf memory:
if a bpf map is charged indirectly for memory consumed from an
interrupt context and allocations are enforced, MEMCG_MAX events are
not raised.
It's not/less of an issue in a generic case because consequent
allocations from a process context will trigger the direct reclaim and
MEMCG_MAX events will be raised. However a bpf map can belong to a
dying/abandoned memory cgroup, so there will be no allocations from a
process context and no MEMCG_MAX events will be triggered.
Link: https://lkml.kernel.org/r/20220702033521.64630-1-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reported-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Restructure the logic in filemap_write_and_wait_range to simplify the code
and make it more consistent with file_write_and_wait_range. No functional
change intended.
Link: https://lkml.kernel.org/r/20220627132351.55680-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since the beginning, charged is set to 0 to avoid calling vm_unacct_memory
twice because vm_unacct_memory will be called by above unmap_region. But
since commit 4f74d2c8e8 ("vm: remove 'nr_accounted' calculations from
the unmap_vmas() interfaces"), unmap_region doesn't call vm_unacct_memory
anymore. So charged shouldn't be set to 0 now otherwise the calling to
paired vm_unacct_memory will be missed and leads to imbalanced account.
Link: https://lkml.kernel.org/r/20220618082027.43391-1-linmiaohe@huawei.com
Fixes: 4f74d2c8e8 ("vm: remove 'nr_accounted' calculations from the unmap_vmas() interfaces")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
syzbot is reporting double kfree() at free_prealloced_shrinker() [1], for
destroy_unused_super() calls free_prealloced_shrinker() even if
prealloc_shrinker() returned an error. Explicitly clear shrinker name
when prealloc_shrinker() called kfree().
[roman.gushchin@linux.dev: zero shrinker->name in all cases where shrinker->name is freed]
Link: https://lkml.kernel.org/r/YtgteTnQTgyuKUSY@castle
Link: https://syzkaller.appspot.com/bug?extid=8b481578352d4637f510 [1]
Link: https://lkml.kernel.org/r/ffa62ece-6a42-2644-16cf-0d33ef32c676@I-love.SAKURA.ne.jp
Fixes: e33c267ab7 ("mm: shrinkers: provide shrinkers with names")
Reported-by: syzbot <syzbot+8b481578352d4637f510@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If hmm_range_fault() is called with the HMM_PFN_REQ_FAULT flag and a
device private PTE is found, the hmm_range::dev_private_owner page is used
to determine if the device private page should not be faulted in.
However, if the device private page is not owned by the caller,
hmm_range_fault() returns an error instead of calling migrate_to_ram() to
fault in the page.
For example, if a page is migrated to GPU private memory and a RDMA fault
capable NIC tries to read the migrated page, without this patch it will
get an error. With this patch, the page will be migrated back to system
memory and the NIC will be able to read the data.
Link: https://lkml.kernel.org/r/20220727000837.4128709-2-rcampbell@nvidia.com
Link: https://lkml.kernel.org/r/20220725183615.4118795-2-rcampbell@nvidia.com
Fixes: 08ddddda66 ("mm/hmm: check the device private page owner in hmm_range_fault()")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reported-by: Felix Kuehling <felix.kuehling@amd.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Philip Yang <Philip.Yang@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There was a report that a task is waiting at the
throttle_direct_reclaim. The pgscan_direct_throttle in vmstat was
increasing.
This is a bug where zone_watermark_fast returns true even when the free
is very low. The commit f27ce0e140 ("page_alloc: consider highatomic
reserve in watermark fast") changed the watermark fast to consider
highatomic reserve. But it did not handle a negative value case which
can be happened when reserved_highatomic pageblock is bigger than the
actual free.
If watermark is considered as ok for the negative value, allocating
contexts for order-0 will consume all free pages without direct reclaim,
and finally free page may become depleted except highatomic free.
Then allocating contexts may fall into throttle_direct_reclaim. This
symptom may easily happen in a system where wmark min is low and other
reclaimers like kswapd does not make free pages quickly.
Handle the negative case by using MIN.
Link: https://lkml.kernel.org/r/20220725095212.25388-1-jaewon31.kim@samsung.com
Fixes: f27ce0e140 ("page_alloc: consider highatomic reserve in watermark fast")
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Reported-by: GyeongHwan Hong <gh21.hong@samsung.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Yong-Taek Lee <ytk.lee@samsung.com>
Cc: <stable@vger.kerenl.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
issues or are too minor to warrant backporting
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Merge tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Thirteen hotfixes.
Eight are cc:stable and the remainder are for post-5.18 issues or are
too minor to warrant backporting"
* tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: update Gao Xiang's email addresses
userfaultfd: provide properly masked address for huge-pages
Revert "ocfs2: mount shared volume without ha stack"
hugetlb: fix memoryleak in hugetlb_mcopy_atomic_pte
fs: sendfile handles O_NONBLOCK of out_fd
ntfs: fix use-after-free in ntfs_ucsncmp()
secretmem: fix unhandled fault in truncate
mm/hugetlb: separate path for hwpoison entry in copy_hugetlb_page_range()
mm: fix missing wake-up event for FSDAX pages
mm: fix page leak with multiple threads mapping the same page
mailmap: update Seth Forshee's email address
tmpfs: fix the issue that the mount and remount results are inconsistent.
mm: kfence: apply kmemleak_ignore_phys on early allocated pool
__kunmap_ {local,atomic}() currently take pointers to void. However, this
is semantically incorrect, since these functions do not change the memory
their arguments point to.
Therefore, make this semantics explicit by modifying the
__kunmap_{local,atomic}() prototypes to take pointers to const void.
As a side effect, compilers may produce more efficient code.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Suggested-by: David Sterba <dsterba@suse.cz>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
* for-next/mte:
arm64: kasan: Revert "arm64: mte: reset the page tag in page->flags"
mm: kasan: Skip page unpoisoning only if __GFP_SKIP_KASAN_UNPOISON
mm: kasan: Skip unpoisoning of user pages
mm: kasan: Ensure the tags are visible before the tag in page->flags
If we're creating a page cache page with FGP_CREAT but FGP_NOWAIT is
set, we should dial back the gfp flags to avoid frivolous blocking
which is trivial to hit in low memory conditions:
[ 10.117661] __schedule+0x8c/0x550
[ 10.118305] schedule+0x58/0xa0
[ 10.118897] schedule_timeout+0x30/0xdc
[ 10.119610] __wait_for_common+0x88/0x114
[ 10.120348] wait_for_completion+0x1c/0x24
[ 10.121103] __flush_work.isra.0+0x16c/0x19c
[ 10.121896] flush_work+0xc/0x14
[ 10.122496] __drain_all_pages+0x144/0x218
[ 10.123267] drain_all_pages+0x10/0x18
[ 10.123941] __alloc_pages+0x464/0x9e4
[ 10.124633] __folio_alloc+0x18/0x3c
[ 10.125294] __filemap_get_folio+0x17c/0x204
[ 10.126084] iomap_write_begin+0xf8/0x428
[ 10.126829] iomap_file_buffered_write+0x144/0x24c
[ 10.127710] xfs_file_buffered_write+0xe8/0x248
[ 10.128553] xfs_file_write_iter+0xa8/0x120
[ 10.129324] io_write+0x16c/0x38c
[ 10.129940] io_issue_sqe+0x70/0x1cc
[ 10.130617] io_queue_sqe+0x18/0xfc
[ 10.131277] io_submit_sqes+0x5d4/0x600
[ 10.131946] __arm64_sys_io_uring_enter+0x224/0x600
[ 10.132752] invoke_syscall.constprop.0+0x70/0xc0
[ 10.133616] do_el0_svc+0xd0/0x118
[ 10.134238] el0_svc+0x78/0xa0
Clear IO, FS, and reclaim flags and mark the allocation as GFP_NOWAIT and
add __GFP_NOWARN to avoid polluting dmesg with pointless allocations
failures. A caller with FGP_NOWAIT must be expected to handle the
resulting -EAGAIN return and retry from a suitable context without NOWAIT
set.
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This adds the helper function balance_dirty_pages_ratelimited_flags().
It adds the parameter flags to balance_dirty_pages_ratelimited().
The flags parameter is passed to balance_dirty_pages(). For async
buffered writes the flag value will be BDP_ASYNC.
If balance_dirty_pages() gets called for async buffered write, we don't
want to wait. Instead we need to indicate to the caller that throttling
is needed so that it can stop writing and offload the rest of the write
to a context that can block.
The new helper function is also used by balance_dirty_pages_ratelimited().
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220623175157.1715274-4-shr@fb.com
[axboe: fix kerneltest bot 'ret' issue]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Transition of wb->dirty_exceeded from 0 to 1 happens before we go to
sleep in balance_dirty_pages() while transition from 1 to 0 happens when
exiting from balance_dirty_pages(), possibly based on old values. This
does not make a lot of sense since wb->dirty_exceeded should simply
reflect whether wb is over dirty limit and so we should ratelimit
entering to balance_dirty_pages() less. Move the two updates together.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Stefan Roesch <shr@fb.com>
Link: https://lore.kernel.org/r/20220623175157.1715274-3-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We start background writeback if we are over background threshold after
exiting the main loop in balance_dirty_pages(). This may result in
basing the decision on already stale values (we may have slept for
significant amount of time) and it is also inconvenient for refactoring
needed for async dirty throttling. Move the check into the main waiting
loop.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Stefan Roesch <shr@fb.com>
Link: https://lore.kernel.org/r/20220623175157.1715274-2-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The core of devm_request_free_mem_region() is a helper that searches for
free space in iomem_resource and performs __request_region_locked() on
the result of that search. The policy choices of the implementation
conform to what CONFIG_DEVICE_PRIVATE users want which is memory that is
immediately marked busy, and a preference to search for the first-fit
free range in descending order from the top of the physical address
space.
CXL has a need for a similar allocator, but with the following tweaks:
1/ Search for free space in ascending order
2/ Search for free space relative to a given CXL window
3/ 'insert' rather than 'request' the new resource given downstream
drivers from the CXL Region driver (like the pmem or dax drivers) are
responsible for request_mem_region() when they activate the memory
range.
Rework __request_free_mem_region() into get_free_mem_region() which
takes a set of GFR_* (Get Free Region) flags to control the allocation
policy (ascending vs descending), and "busy" policy (insert_resource()
vs request_region()).
As part of the consolidation of the legacy GFR_REQUEST_REGION case with
the new default of just inserting a new resource into the free space
some minor cleanups like not checking for NULL before calling
devres_free() (which does its own check) is included.
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/linux-cxl/20220420143406.GY2120790@nvidia.com/
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165784333333.1758207.13703329337805274043.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that only SLOB use __kmem_cache_{alloc,free}_bulk(), move them to
SLOB. No functional change intended.
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
There is no benefit to call generic bulk free function when
kmem_cache_alloc_bulk() failed. Use own kmem_cache_free_bulk()
instead of generic function.
Note that if kmem_cache_alloc_bulk() fails to allocate first object in
SLUB, size is zero. So allow passing size == 0 to kmem_cache_free_bulk()
like SLAB's.
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
THP_SWAP has been proven to improve the swap throughput significantly
on x86_64 according to commit bd4c82c22c ("mm, THP, swap: delay
splitting THP after swapped out").
As long as arm64 uses 4K page size, it is quite similar with x86_64
by having 2MB PMD THP. THP_SWAP is architecture-independent, thus,
enabling it on arm64 will benefit arm64 as well.
A corner case is that MTE has an assumption that only base pages
can be swapped. We won't enable THP_SWAP for ARM64 hardware with
MTE support until MTE is reworked to coexist with THP_SWAP.
A micro-benchmark is written to measure thp swapout throughput as
below,
unsigned long long tv_to_ms(struct timeval tv)
{
return tv.tv_sec * 1000 + tv.tv_usec / 1000;
}
main()
{
struct timeval tv_b, tv_e;;
#define SIZE 400*1024*1024
volatile void *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (!p) {
perror("fail to get memory");
exit(-1);
}
madvise(p, SIZE, MADV_HUGEPAGE);
memset(p, 0x11, SIZE); /* write to get mem */
gettimeofday(&tv_b, NULL);
madvise(p, SIZE, MADV_PAGEOUT);
gettimeofday(&tv_e, NULL);
printf("swp out bandwidth: %ld bytes/ms\n",
SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
}
Testing is done on rk3568 64bit Quad Core Cortex-A55 platform -
ROCK 3A.
thp swp throughput w/o patch: 2734bytes/ms (mean of 10 tests)
thp swp throughput w/ patch: 3331bytes/ms (mean of 10 tests)
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Link: https://lore.kernel.org/r/20220720093737.133375-1-21cnbao@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
When alloc_huge_page fails, *pagep is set to NULL without put_page first.
So the hugepage indicated by *pagep is leaked.
Link: https://lkml.kernel.org/r/20220709092629.54291-1-linmiaohe@huawei.com
Fixes: 8cc5fcbb5b ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Originally copy_hugetlb_page_range() handles migration entries and
hwpoisoned entries in similar manner. But recently the related code path
has more code for migration entries, and when
is_writable_migration_entry() was converted to
!is_readable_migration_entry(), hwpoison entries on source processes got
to be unexpectedly updated (which is legitimate for migration entries, but
not for hwpoison entries). This results in unexpected serious issues like
kernel panic when forking processes with hwpoison entries in pmd.
Separate the if branch into one for hwpoison entries and one for migration
entries.
Link: https://lkml.kernel.org/r/20220704013312.2415700-3-naoya.horiguchi@linux.dev
Fixes: 6c287605fd ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org> [5.18]
Cc: David Hildenbrand <david@redhat.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
FSDAX page refcounts are 1-based, rather than 0-based: if refcount is
1, then the page is freed. The FSDAX pages can be pinned through GUP,
then they will be unpinned via unpin_user_page() using a folio variant
to put the page, however, folio variants did not consider this special
case, the result will be to miss a wakeup event (like the user of
__fuse_dax_break_layouts()). This results in a task being permanently
stuck in TASK_INTERRUPTIBLE state.
Since FSDAX pages are only possibly obtained by GUP users, so fix GUP
instead of folio_put() to lower overhead.
Link: https://lkml.kernel.org/r/20220705123532.283-1-songmuchun@bytedance.com
Fixes: d8ddc099c6 ("mm/gup: Add gup_put_folio()")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We have an application with a lot of threads that use a shared mmap backed
by tmpfs mounted with -o huge=within_size. This application started
leaking loads of huge pages when we upgraded to a recent kernel.
Using the page ref tracepoints and a BPF program written by Tejun Heo we
were able to determine that these pages would have multiple refcounts from
the page fault path, but when it came to unmap time we wouldn't drop the
number of refs we had added from the faults.
I wrote a reproducer that mmap'ed a file backed by tmpfs with -o
huge=always, and then spawned 20 threads all looping faulting random
offsets in this map, while using madvise(MADV_DONTNEED) randomly for huge
page aligned ranges. This very quickly reproduced the problem.
The problem here is that we check for the case that we have multiple
threads faulting in a range that was previously unmapped. One thread maps
the PMD, the other thread loses the race and then returns 0. However at
this point we already have the page, and we are no longer putting this
page into the processes address space, and so we leak the page. We
actually did the correct thing prior to f9ce0be71d, however it looks
like Kirill copied what we do in the anonymous page case. In the
anonymous page case we don't yet have a page, so we don't have to drop a
reference on anything. Previously we did the correct thing for file based
faults by returning VM_FAULT_NOPAGE so we correctly drop the reference on
the page we faulted in.
Fix this by returning VM_FAULT_NOPAGE in the pmd_devmap_trans_unstable()
case, this makes us drop the ref on the page properly, and now my
reproducer no longer leaks the huge pages.
[josef@toxicpanda.com: v2]
Link: https://lkml.kernel.org/r/e90c8f0dbae836632b669c2afc434006a00d4a67.1657721478.git.josef@toxicpanda.com
Link: https://lkml.kernel.org/r/2b798acfd95c9ab9395fe85e8d5a835e2e10a920.1657051137.git.josef@toxicpanda.com
Fixes: f9ce0be71d ("mm: Cleanup faultaround and finish_fault() codepaths")
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
An undefined-behavior issue has not been completely fixed since commit
d14f5efadd ("tmpfs: fix undefined-behaviour in shmem_reconfigure()").
In the commit, check in the shmem_reconfigure() is added in remount
process to avoid the Ubsan problem. However, the check is not added to
the mount process. It causes inconsistent results between mount and
remount. The operations to reproduce the problem in user mode as follows:
If nr_blocks is set to 0x8000000000000000, the mounting is successful.
# mount tmpfs /dev/shm/ -t tmpfs -o nr_blocks=0x8000000000000000
However, when -o remount is used, the mount fails because of the
check in the shmem_reconfigure()
# mount tmpfs /dev/shm/ -t tmpfs -o remount,nr_blocks=0x8000000000000000
mount: /dev/shm: mount point not mounted or bad option.
Therefore, add checks in the shmem_parse_one() function and remove the
check in shmem_reconfigure() to avoid this problem.
Link: https://lkml.kernel.org/r/20220629124324.1640807-1-wangzhaolong1@huawei.com
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Cc: Luo Meng <luomeng12@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This patch solves two issues.
(1) The pool allocated by memblock needs to unregister from
kmemleak scanning. Apply kmemleak_ignore_phys to replace the
original kmemleak_free as its address now is stored in the phys tree.
(2) The pool late allocated by page-alloc doesn't need to unregister.
Move out the freeing operation from its call path.
Link: https://lkml.kernel.org/r/20220628113714.7792-2-yee.lee@mediatek.com
Fixes: 0c24e06119 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Yee Lee <yee.lee@mediatek.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mmget_still_valid() has already been removed via commit 4d45e75a99 ("mm:
remove the now-unnecessary mmget_still_valid() hack"). Update the
corresponding comment.
Link: https://lkml.kernel.org/r/20220709092527.47778-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper function huge_pte_lock() to lock the huge pte to simplify the
code a bit. No functional change intended.
Link: https://lkml.kernel.org/r/20220709092440.43018-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use try_cmpxchg instead of cmpxchg in set_pfnblock_flags_mask. x86
CMPXCHG instruction returns success in ZF flag, so this change saves a
compare after cmpxchg (and related move instruction in front of cmpxchg).
The main loop improves from:
1c5d: 48 89 c2 mov %rax,%rdx
1c60: 48 89 c1 mov %rax,%rcx
1c63: 48 21 fa and %rdi,%rdx
1c66: 4c 09 c2 or %r8,%rdx
1c69: f0 48 0f b1 16 lock cmpxchg %rdx,(%rsi)
1c6e: 48 39 c1 cmp %rax,%rcx
1c71: 75 ea jne 1c5d <...>
to:
1c60: 48 89 ca mov %rcx,%rdx
1c63: 48 21 c2 and %rax,%rdx
1c66: 4c 09 c2 or %r8,%rdx
1c69: f0 48 0f b1 16 lock cmpxchg %rdx,(%rsi)
1c6e: 75 f0 jne 1c60 <...>
Link: https://lkml.kernel.org/r/20220708140736.8737-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kmemleak recently added a rbtree to store the objects allocted with
physical address. Those objects can't be freed with kmemleak_free().
According to the comments, percpu allocations are tracked by kmemleak
separately. Kmemleak_free() was used to avoid the unnecessary
tracking. If kmemleak_free() fails, those objects would be scanned by
kmemleak, which is unnecessary but shouldn't lead to other effects.
Use kmemleak_ignore_phys() instead of kmemleak_free() for those
objects.
Link: https://lkml.kernel.org/r/20220705113158.127600-1-patrick.wang.shcn@gmail.com
Fixes: 0c24e06119 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The variable error will be assigned correctly before it is used, the
initialization is redundant, so remove it.
Link: https://lkml.kernel.org/r/20220704114112.163112-1-xiujianfeng@huawei.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro IS_ERR_OR_NULL to check the validity of page to simplify
the code. Minor readability improvement.
Link: https://lkml.kernel.org/r/20220704132201.14611-17-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It's dangerous and wrong to call page_folio(pmd_page(*pmd)) when pmd isn't
present. But the caller guarantees pmd is present when folio is set. So we
should be safe here. Add comment to make it clear.
Link: https://lkml.kernel.org/r/20220704132201.14611-16-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We use page->mapping and page->index, instead of page->indexlru in second
tail page as list_head. Correct it.
Link: https://lkml.kernel.org/r/20220704132201.14611-15-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There is nothing to do if a zone doesn't have any pages managed by the
buddy allocator. So we should check managed_zone instead. Also if a thp
is found, there's no need to traverse the subpages again.
Link: https://lkml.kernel.org/r/20220704132201.14611-13-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Subpages in swapcache won't be freed even if it is the last user of the
page until next time reclaim. It shouldn't hurt indeed, but we could try
to free these pages to save more memory for system.
Link: https://lkml.kernel.org/r/20220704132201.14611-12-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The comment about deposited pgtable is borrowed from zap_huge_pmd but
there's no deposited pgtable stuff for huge pud in zap_huge_pud. Remove
it to avoid confusion.
Link: https://lkml.kernel.org/r/20220704132201.14611-10-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper macro __ATTR_RW to define use_zero_page_attr, defrag_attr and
enabled_attr to make code more clear. Minor readability improvement.
Link: https://lkml.kernel.org/r/20220704132201.14611-9-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper function vma_lookup to lookup the needed vma to simplify the
code. Minor readability improvement.
Link: https://lkml.kernel.org/r/20220704132201.14611-8-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mmun_start indicates mmu_notifier start address but there's no mmu_notifier
stuff in remove_migration_pmd. This will make it hard to get the meaning of
mmun_start. Rename it to haddr to avoid confusing readers and also imporve
readability.
Link: https://lkml.kernel.org/r/20220704132201.14611-7-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper touch_pmd to set pmd accessed to simplify the code and improve
the readability. No functional change intended.
Link: https://lkml.kernel.org/r/20220704132201.14611-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use helper touch_pud to set pud accessed to simplify the code and improve
the readability. No functional change intended.
Link: https://lkml.kernel.org/r/20220704132201.14611-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__pud_trans_huge_lock returns page table lock pointer if a given pud maps
a thp instead of 'true' since introduced. Fix corresponding comments.
Link: https://lkml.kernel.org/r/20220704132201.14611-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
vma->vm_page_prot is read lockless from the rmap_walk, it may be updated
concurrently. Using READ_ONCE to prevent the risk of reading intermediate
values.
Link: https://lkml.kernel.org/r/20220704132201.14611-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "A few cleanup patches for huge_memory", v3.
This series contains a few cleaup patches to remove duplicated codes,
add/use helper functions, fix some obsolete comments and so on. More
details can be found in the respective changelogs.
This patch (of 16):
Arches with special requirements for evicting THP backing TLB entries can
implement flush_pmd_tlb_range. Otherwise also, it can help optimize TLB
flush in THP regime. Using flush_pmd_tlb_range to take advantage of this
in move_huge_pmd.
Link: https://lkml.kernel.org/r/20220704132201.14611-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220704132201.14611-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Now all the platforms enable ARCH_HAS_GET_PAGE_PROT. They define and
export own vm_get_page_prot() whether custom or standard
DECLARE_VM_GET_PAGE_PROT. Hence there is no need for default generic
fallback for vm_get_page_prot(). Just drop this fallback and also
ARCH_HAS_GET_PAGE_PROT mechanism.
Link: https://lkml.kernel.org/r/20220711070600.2378316-27-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This just converts the generic vm_get_page_prot() implementation into a
new macro i.e DECLARE_VM_GET_PAGE_PROT which later can be used across
platforms when enabling them with ARCH_HAS_VM_GET_PAGE_PROT. This does
not create any functional change.
Link: https://lkml.kernel.org/r/20220711070600.2378316-3-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/mmap: Drop __SXXX/__PXXX macros from across platforms",
v7.
__SXXX/__PXXX macros are unnecessary abstraction layer in creating the
generic protection_map[] array which is used for vm_get_page_prot(). This
abstraction layer can be avoided, if the platforms just define the array
protection_map[] for all possible vm_flags access permission combinations
and also export vm_get_page_prot() implementation.
This series drops __SXXX/__PXXX macros from across platforms in the tree.
First it build protects generic protection_map[] array with '#ifdef
__P000' and moves it inside platforms which enable
ARCH_HAS_VM_GET_PAGE_PROT. Later this build protects same array with
'#ifdef ARCH_HAS_VM_GET_PAGE_PROT' and moves inside remaining platforms
while enabling ARCH_HAS_VM_GET_PAGE_PROT. This adds a new macro
DECLARE_VM_GET_PAGE_PROT defining the current generic vm_get_page_prot(),
in order for it to be reused on platforms that do not require custom
implementation. Finally, ARCH_HAS_VM_GET_PAGE_PROT can just be dropped,
as all platforms now define and export vm_get_page_prot(), via looking up
a private and static protection_map[] array. protection_map[] data type
has been changed as 'static const' on all platforms that do not change it
during boot.
This patch (of 26):
Build protect generic protection_map[] array with __P000, so that it can
be moved inside all the platforms one after the other. Otherwise there
will be build failures during this process.
CONFIG_ARCH_HAS_VM_GET_PAGE_PROT cannot be used for this purpose as only
certain platforms enable this config now.
Link: https://lkml.kernel.org/r/20220711070600.2378316-1-anshuman.khandual@arm.com
Link: https://lkml.kernel.org/r/20220711070600.2378316-2-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Functions that work on a pointer to virtual memory such as virt_to_pfn()
and users of that function such as virt_to_page() are supposed to pass a
pointer to virtual memory, ideally a (void *) or other pointer. However
since many architectures implement virt_to_pfn() as a macro, this function
becomes polymorphic and accepts both a (unsigned long) and a (void *).
If we instead implement a proper virt_to_pfn(void *addr) function the
following happens (occurred on arch/arm):
mm/nommu.c: In function 'free_page_series':
mm/nommu.c:501:50: warning: passing argument 1 of 'virt_to_pfn'
makes pointer from integer without a cast [-Wint-conversion]
struct page *page = virt_to_page(from);
Fix this with an explicit cast.
Link: https://lkml.kernel.org/r/20220630084124.691207-6-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Functions that work on a pointer to virtual memory such as virt_to_pfn()
and users of that function such as virt_to_page() are supposed to pass a
pointer to virtual memory, ideally a (void *) or other pointer. However
since many architectures implement virt_to_pfn() as a macro, this function
becomes polymorphic and accepts both a (unsigned long) and a (void *).
If we instead implement a proper virt_to_pfn(void *addr) function the
following happens (occurred on arch/arm):
mm/gup.c: In function '__get_user_pages_locked':
mm/gup.c:1599:49: warning: passing argument 1 of 'virt_to_pfn'
makes pointer from integer without a cast [-Wint-conversion]
pages[i] = virt_to_page(start);
Fix this with an explicit cast.
Link: https://lkml.kernel.org/r/20220630084124.691207-5-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Functions that work on a pointer to virtual memory such as virt_to_pfn()
and users of that function such as virt_to_page() are supposed to pass a
pointer to virtual memory, ideally a (void *) or other pointer. However
since many architectures implement virt_to_pfn() as a macro, this function
becomes polymorphic and accepts both a (unsigned long) and a (void *).
If we instead implement a proper virt_to_pfn(void *addr) function the
following happens (occurred on arch/arm):
mm/kfence/core.c:558:30: warning: passing argument 1
of 'virt_to_pfn' makes pointer from integer without a
cast [-Wint-conversion]
In one case we can refer to __kfence_pool directly (and that is a proper
(char *) pointer) and in the other call site we use an explicit cast.
Link: https://lkml.kernel.org/r/20220630084124.691207-4-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Functions that work on a pointer to virtual memory such as virt_to_pfn()
and users of that function such as virt_to_page() are supposed to pass a
pointer to virtual memory, ideally a (void *) or other pointer. However
since many architectures implement virt_to_pfn() as a macro, this function
becomes polymorphic and accepts both a (unsigned long) and a (void *).
If we instead implement a proper virt_to_pfn(void *addr) function the
following happens (occurred on arch/arm):
mm/highmem.c:153:29: warning: passing argument 1 of
'virt_to_pfn' makes pointer from integer without a
cast [-Wint-conversion]
We already have a proper void * pointer in the scope of this function
named "vaddr" so pass that instead.
Link: https://lkml.kernel.org/r/20220630084124.691207-3-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mem_cgroup_kmem_disabled() checks whether the kmem accounting is off.
Therefore, replace cgroup_memory_nokmem with mem_cgroup_kmem_disabled(),
which is the same work in percpu.c and slab_common.c.
Link: https://lkml.kernel.org/r/20220625061844.226764-1-xiangyang3@huawei.com
Signed-off-by: Xiang Yang <xiangyang3@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Souptick Joarder (HPE) <jrdr.linux@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
struct per_cpu_pages is no longer strictly local as PCP lists can be
drained remotely using a lock for protection. While the use of local_lock
works, it goes against the intent of local_lock which is for "pure CPU
local concurrency control mechanisms and not suited for inter-CPU
concurrency control" (Documentation/locking/locktypes.rst)
local_lock protects against migration between when the percpu pointer is
accessed and the pcp->lock acquired. The lock acquisition is a preemption
point so in the worst case, a task could migrate to another NUMA node and
accidentally allocate remote memory. The main requirement is to pin the
task to a CPU that is suitable for PREEMPT_RT and !PREEMPT_RT.
Replace local_lock with helpers that pin a task to a CPU, lookup the
per-cpu structure and acquire the embedded lock. It's similar to
local_lock without breaking the intent behind the API. It is not a
complete API as only the parts needed for PCP-alloc are implemented but in
theory, the generic helpers could be promoted to a general API if there
was demand for an embedded lock within a per-cpu struct with a guarantee
that the per-cpu structure locked matches the running CPU and cannot use
get_cpu_var due to RT concerns. PCP requires these semantics to avoid
accidentally allocating remote memory.
[mgorman@techsingularity.net: use pcp_spin_trylock_irqsave instead of pcpu_spin_trylock_irqsave]
Link: https://lkml.kernel.org/r/20220627084645.GA27531@techsingularity.net
Link: https://lkml.kernel.org/r/20220624125423.6126-8-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Some setups, notably NOHZ_FULL CPUs, are too busy to handle the per-cpu
drain work queued by __drain_all_pages(). So introduce a new mechanism to
remotely drain the per-cpu lists. It is made possible by remotely locking
'struct per_cpu_pages' new per-cpu spinlocks. A benefit of this new
scheme is that drain operations are now migration safe.
There was no observed performance degradation vs. the previous scheme.
Both netperf and hackbench were run in parallel to triggering the
__drain_all_pages(NULL, true) code path around ~100 times per second. The
new scheme performs a bit better (~5%), although the important point here
is there are no performance regressions vs. the previous mechanism.
Per-cpu lists draining happens only in slow paths.
Minchan Kim tested an earlier version and reported;
My workload is not NOHZ CPUs but run apps under heavy memory
pressure so they goes to direct reclaim and be stuck on
drain_all_pages until work on workqueue run.
unit: nanosecond
max(dur) avg(dur) count(dur)
166713013 487511.77786438033 1283
From traces, system encountered the drain_all_pages 1283 times and
worst case was 166ms and avg was 487us.
The other problem was alloc_contig_range in CMA. The PCP draining
takes several hundred millisecond sometimes though there is no
memory pressure or a few of pages to be migrated out but CPU were
fully booked.
Your patch perfectly removed those wasted time.
Link: https://lkml.kernel.org/r/20220624125423.6126-7-mgorman@techsingularity.net
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Yu Zhao <yuzhao@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently the PCP lists are protected by using local_lock_irqsave to
prevent migration and IRQ reentrancy but this is inconvenient. Remote
draining of the lists is impossible and a workqueue is required and every
task allocation/free must disable then enable interrupts which is
expensive.
As preparation for dealing with both of those problems, protect the
lists with a spinlock. The IRQ-unsafe version of the lock is used
because IRQs are already disabled by local_lock_irqsave. spin_trylock
is used in combination with local_lock_irqsave() but later will be
replaced with a spin_trylock_irqsave when the local_lock is removed.
The per_cpu_pages still fits within the same number of cache lines after
this patch relative to before the series.
struct per_cpu_pages {
spinlock_t lock; /* 0 4 */
int count; /* 4 4 */
int high; /* 8 4 */
int batch; /* 12 4 */
short int free_factor; /* 16 2 */
short int expire; /* 18 2 */
/* XXX 4 bytes hole, try to pack */
struct list_head lists[13]; /* 24 208 */
/* size: 256, cachelines: 4, members: 7 */
/* sum members: 228, holes: 1, sum holes: 4 */
/* padding: 24 */
} __attribute__((__aligned__(64)));
There is overhead in the fast path due to acquiring the spinlock even
though the spinlock is per-cpu and uncontended in the common case. Page
Fault Test (PFT) running on a 1-socket reported the following results on a
1 socket machine.
5.19.0-rc3 5.19.0-rc3
vanilla mm-pcpspinirq-v5r16
Hmean faults/sec-1 869275.7381 ( 0.00%) 874597.5167 * 0.61%*
Hmean faults/sec-3 2370266.6681 ( 0.00%) 2379802.0362 * 0.40%*
Hmean faults/sec-5 2701099.7019 ( 0.00%) 2664889.7003 * -1.34%*
Hmean faults/sec-7 3517170.9157 ( 0.00%) 3491122.8242 * -0.74%*
Hmean faults/sec-8 3965729.6187 ( 0.00%) 3939727.0243 * -0.66%*
There is a small hit in the number of faults per second but given that the
results are more stable, it's borderline noise.
[akpm@linux-foundation.org: add missing local_unlock_irqrestore() on contention path]
Link: https://lkml.kernel.org/r/20220624125423.6126-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If a page allocation fails, the ZONE_BOOSTER_WATERMARK should be tested,
cleared and kswapd woken whether the allocation attempt was via the PCP or
directly via the buddy list.
Remove the page == NULL so the ZONE_BOOSTED_WATERMARK bit is checked
unconditionally. As it is unlikely that ZONE_BOOSTED_WATERMARK is set,
mark the branch accordingly.
Link: https://lkml.kernel.org/r/20220624125423.6126-5-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This is a preparation page to allow the buddy removal code to be reused in
a later patch.
No functional change.
Link: https://lkml.kernel.org/r/20220624125423.6126-4-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The per_cpu_pages is cache-aligned on a standard x86-64 distribution
configuration but a later patch will add a new field which would push the
structure into the next cache line. Use only one list to store THP-sized
pages on the per-cpu list. This assumes that the vast majority of
THP-sized allocations are GFP_MOVABLE but even if it was another type, it
would not contribute to serious fragmentation that potentially causes a
later THP allocation failure. Align per_cpu_pages on the cacheline
boundary to ensure there is no false cache sharing.
After this patch, the structure sizing is;
struct per_cpu_pages {
int count; /* 0 4 */
int high; /* 4 4 */
int batch; /* 8 4 */
short int free_factor; /* 12 2 */
short int expire; /* 14 2 */
struct list_head lists[13]; /* 16 208 */
/* size: 256, cachelines: 4, members: 6 */
/* padding: 32 */
} __attribute__((__aligned__(64)));
Link: https://lkml.kernel.org/r/20220624125423.6126-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Drain remote per-cpu directly", v5.
Some setups, notably NOHZ_FULL CPUs, may be running realtime or
latency-sensitive applications that cannot tolerate interference due to
per-cpu drain work queued by __drain_all_pages(). Introduce a new
mechanism to remotely drain the per-cpu lists. It is made possible by
remotely locking 'struct per_cpu_pages' new per-cpu spinlocks. This has
two advantages, the time to drain is more predictable and other unrelated
tasks are not interrupted.
This series has the same intent as Nicolas' series "mm/page_alloc: Remote
per-cpu lists drain support" -- avoid interference of a high priority task
due to a workqueue item draining per-cpu page lists. While many workloads
can tolerate a brief interruption, it may cause a real-time task running
on a NOHZ_FULL CPU to miss a deadline and at minimum, the draining is
non-deterministic.
Currently an IRQ-safe local_lock protects the page allocator per-cpu
lists. The local_lock on its own prevents migration and the IRQ disabling
protects from corruption due to an interrupt arriving while a page
allocation is in progress.
This series adjusts the locking. A spinlock is added to struct
per_cpu_pages to protect the list contents while local_lock_irq is
ultimately replaced by just the spinlock in the final patch. This allows
a remote CPU to safely. Follow-on work should allow the spin_lock_irqsave
to be converted to spin_lock to avoid IRQs being disabled/enabled in most
cases. The follow-on patch will be one kernel release later as it is
relatively high risk and it'll make bisections more clear if there are any
problems.
Patch 1 is a cosmetic patch to clarify when page->lru is storing buddy pages
and when it is storing per-cpu pages.
Patch 2 shrinks per_cpu_pages to make room for a spin lock. Strictly speaking
this is not necessary but it avoids per_cpu_pages consuming another
cache line.
Patch 3 is a preparation patch to avoid code duplication.
Patch 4 is a minor correction.
Patch 5 uses a spin_lock to protect the per_cpu_pages contents while still
relying on local_lock to prevent migration, stabilise the pcp
lookup and prevent IRQ reentrancy.
Patch 6 remote drains per-cpu pages directly instead of using a workqueue.
Patch 7 uses a normal spinlock instead of local_lock for remote draining
This patch (of 7):
The page allocator uses page->lru for storing pages on either buddy or PCP
lists. Create page->buddy_list and page->pcp_list as a union with
page->lru. This is simply to clarify what type of list a page is on in
the page allocator.
No functional change intended.
[minchan@kernel.org: fix page lru fields in macros]
Link: https://lkml.kernel.org/r/20220624125423.6126-2-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Lazy page table copying at fork time was introduced with commit
d992895ba2 ("[PATCH] Lazy page table copies in fork()"). At the time,
hugetlb was very new and did not support page faulting. As a result, it
was excluded. When full page fault support was added for hugetlb, the
exclusion was not removed.
Simply remove the check that prevents lazy copying of hugetlb page tables
at fork. Of course, like other mappings this only applies to shared
mappings.
Lazy page table copying at fork will be less advantageous for hugetlb
mappings because:
- There are fewer page table entries with hugetlb
- hugetlb pmds can be shared instead of copied
In any case, completely eliminating the copy at fork time should speed
things up.
Link: https://lkml.kernel.org/r/20220621235620.291305-5-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: James Houghton <jthoughton@google.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
As an optimization for loops sequentially processing hugetlb address
ranges, huge_pmd_unshare would update a passed address if it unshared a
pmd. Updating a loop control variable outside the loop like this is
generally a bad idea. These loops are now using hugetlb_mask_last_page to
optimize scanning when non-present ptes are discovered. The same can be
done when huge_pmd_unshare returns 1 indicating a pmd was unshared.
Remove address update from huge_pmd_unshare. Change the passed argument
type and update all callers. In loops sequentially processing addresses
use hugetlb_mask_last_page to update address if pmd is unshared.
[sfr@canb.auug.org.au: fix an unused variable warning/error]
Link: https://lkml.kernel.org/r/20220622171117.70850960@canb.auug.org.au
Link: https://lkml.kernel.org/r/20220621235620.291305-4-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Will Deacon <will@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "hugetlb: speed up linear address scanning", v2.
At unmap, fork and remap time hugetlb address ranges are linearly scanned.
We can optimize these scans if the ranges are sparsely populated.
Also, enable page table "Lazy copy" for hugetlb at fork.
NOTE: Architectures not defining CONFIG_ARCH_WANT_GENERAL_HUGETLB need to
add an arch specific version hugetlb_mask_last_page() to take advantage of
sparse address scanning improvements. Baolin Wang added the routine for
arm64. Other architectures which could be optimized are: ia64, mips,
parisc, powerpc, s390, sh and sparc.
This patch (of 4):
HugeTLB address ranges are linearly scanned during fork, unmap and remap
operations. If a non-present entry is encountered, the code currently
continues to the next huge page aligned address. However, a non-present
entry implies that the page table page for that entry is not present.
Therefore, the linear scan can skip to the end of range mapped by the page
table page. This can speed operations on large sparsely populated hugetlb
mappings.
Create a new routine hugetlb_mask_last_page() that will return an address
mask. When the mask is ORed with an address, the result will be the
address of the last huge page mapped by the associated page table page.
Use this mask to update addresses in routines which linearly scan hugetlb
address ranges when a non-present pte is encountered.
hugetlb_mask_last_page is related to the implementation of huge_pte_offset
as hugetlb_mask_last_page is called when huge_pte_offset returns NULL.
This patch only provides a complete hugetlb_mask_last_page implementation
when CONFIG_ARCH_WANT_GENERAL_HUGETLB is defined. Architectures which
provide their own versions of huge_pte_offset can also provide their own
version of hugetlb_mask_last_page.
Link: https://lkml.kernel.org/r/20220621235620.291305-1-mike.kravetz@oracle.com
Link: https://lkml.kernel.org/r/20220621235620.291305-2-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: James Houghton <jthoughton@google.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently, KASAN describes all invalid-free/double-free bugs as
"double-free or invalid-free". This is ambiguous.
KASAN should report "double-free" when a double-free is a more likely
cause (the address points to the start of an object) and report
"invalid-free" otherwise [1].
[1] https://bugzilla.kernel.org/show_bug.cgi?id=212193
Link: https://lkml.kernel.org/r/20220615062219.22618-1-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Cc: Andrew Yang <andrew.yang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The khugepaged_{enabled|always|req_madv} are not khugepaged only anymore,
move them to huge_mm.h and rename to hugepage_flags_xxx, and remove
khugepaged_req_madv due to no users.
Also move khugepaged_defrag to khugepaged.c since its only caller is in
that file, it doesn't have to be in a header file.
Link: https://lkml.kernel.org/r/20220616174840.1202070-7-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The page fault path checks THP eligibility with __transhuge_page_enabled()
which does the similar thing as hugepage_vma_check(), so use
hugepage_vma_check() instead.
However page fault allows DAX and !anon_vma cases, so added a new flag,
in_pf, to hugepage_vma_check() to make page fault work correctly.
The in_pf flag is also used to skip shmem and file THP for page fault
since shmem handles THP in its own shmem_fault() and file THP allocation
on fault is not supported yet.
Also remove hugepage_vma_enabled() since hugepage_vma_check() is the only
caller now, it is not necessary to have a helper function.
Link: https://lkml.kernel.org/r/20220616174840.1202070-6-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The transparent_hugepage_active() was introduced to show THP eligibility
bit in smaps in proc, smaps is the only user. But it actually does the
similar check as hugepage_vma_check() which is used by khugepaged. We
definitely don't have to maintain two similar checks, so kill
transparent_hugepage_active().
This patch also fixed the wrong behavior for VM_NO_KHUGEPAGED vmas.
Also move hugepage_vma_check() to huge_memory.c and huge_mm.h since it
is not only for khugepaged anymore.
[akpm@linux-foundation.org: check vma->vm_mm, per Zach]
[akpm@linux-foundation.org: add comment to vdso check]
Link: https://lkml.kernel.org/r/20220616174840.1202070-5-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The hugepage_vma_revalidate() needs to check if the vma is still anonymous
vma or not since the address may be unmapped then remapped to file before
khugepaged reaquired the mmap_lock.
The old comment is not quite helpful, elaborate this with better comment.
Link: https://lkml.kernel.org/r/20220616174840.1202070-4-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are couple of places that check whether the vma size is ok for THP
or whether address fits, they are open coded and duplicate, use
transhuge_vma_suitable() to do the job by passing in (vma->end -
HPAGE_PMD_SIZE).
Move vma size check into hugepage_vma_check(). This will make
khugepaged_enter() is as same as khugepaged_enter_vma(). There is just
one caller for khugepaged_enter(), replace it to khugepaged_enter_vma()
and remove khugepaged_enter().
Link: https://lkml.kernel.org/r/20220616174840.1202070-3-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Cleanup transhuge_xxx helpers", v5.
This series is the follow-up of the discussion about cleaning up
transhuge_xxx helpers at
https://lore.kernel.org/linux-mm/627a71f8-e879-69a5-ceb3-fc8d29d2f7f1@suse.cz/.
THP has a bunch of helpers that do VMA sanity check for different paths,
they do the similar checks for the most callsites and have a lot duplicate
codes. And it is confusing what helpers should be used at what
conditions.
This series reorganized and cleaned up the code so that we could
consolidate all the checks into hugepage_vma_check().
The transhuge_vma_enabled(), transparent_hugepage_active() and
__transparent_hugepage_enabled() are killed by this series.
This patch (of 7):
Currently the THP flag check in hugepage_vma_check() will fallthrough if
the flag is NEVER and VM_HUGEPAGE is set. This is not a problem for now
since all the callers have the flag checked before or can't be invoked if
the flag is NEVER.
However, the following patch will call hugepage_vma_check() in more
places, for example, page fault, so this flag must be checked in
hugepge_vma_check().
Link: https://lkml.kernel.org/r/20220616174840.1202070-1-shy828301@gmail.com
Link: https://lkml.kernel.org/r/20220616174840.1202070-2-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This new function is a variant of mf_generic_kill_procs that accepts a
file, offset pair instead of a struct to support multiple files sharing a
DAX mapping. It is intended to be called by the file systems as part of
the memory_failure handler after the file system performed a reverse
mapping from the storage address to the file and file offset.
Link: https://lkml.kernel.org/r/20220603053738.1218681-6-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.wiliams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When memory-failure occurs, we call this function which is implemented by
each kind of devices. For the fsdax case, pmem device driver implements
it. Pmem device driver will find out the filesystem in which the
corrupted page located in.
With dax_holder notify support, we are able to notify the memory failure
from pmem driver to upper layers. If there is something not support in
the notify routine, memory_failure will fall back to the generic hanlder.
Link: https://lkml.kernel.org/r/20220603053738.1218681-4-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.wiliams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
memory_failure_dev_pagemap code is a bit complex before introduce RMAP
feature for fsdax. So it is needed to factor some helper functions to
simplify these code.
[akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n build]
[zhengbin13@huawei.com: fix redefinition of mf_generic_kill_procs]
Link: https://lkml.kernel.org/r/20220628112143.1170473-1-zhengbin13@huawei.com
Link: https://lkml.kernel.org/r/20220603053738.1218681-3-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.wiliams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently any attempts to pin a device coherent page will fail. This is
because device coherent pages need to be managed by a device driver, and
pinning them would prevent a driver from migrating them off the device.
However this is no reason to fail pinning of these pages. These are
coherent and accessible from the CPU so can be migrated just like pinning
ZONE_MOVABLE pages. So instead of failing all attempts to pin them first
try migrating them out of ZONE_DEVICE.
[hch@lst.de: rebased to the split device memory checks, moved migrate_device_page to migrate_device.c]
Link: https://lkml.kernel.org/r/20220715150521.18165-7-alex.sierra@amd.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This case is used to migrate pages from device memory, back to system
memory. Device coherent type memory is cache coherent from device and CPU
point of view.
Link: https://lkml.kernel.org/r/20220715150521.18165-6-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Alistair Poppple <apopple@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
With DEVICE_COHERENT, we'll soon have vm_normal_pages() return
device-managed anonymous pages that are not LRU pages. Although they
behave like normal pages for purposes of mapping in CPU page, and for COW.
They do not support LRU lists, NUMA migration or THP.
Callers to follow_page() currently don't expect ZONE_DEVICE pages,
however, with DEVICE_COHERENT we might now return ZONE_DEVICE. Check for
ZONE_DEVICE pages in applicable users of follow_page() as well.
Link: https://lkml.kernel.org/r/20220715150521.18165-5-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> [v2]
Reviewed-by: Alistair Popple <apopple@nvidia.com> [v6]
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Device memory that is cache coherent from device and CPU point of view.
This is used on platforms that have an advanced system bus (like CAPI or
CXL). Any page of a process can be migrated to such memory. However, no
one should be allowed to pin such memory so that it can always be evicted.
[hch@lst.de: rebased ontop of the refcount changes, remove is_dev_private_or_coherent_page]
Link: https://lkml.kernel.org/r/20220715150521.18165-4-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Add MEMORY_DEVICE_COHERENT for coherent device memory
mapping", v9.
This patch series introduces MEMORY_DEVICE_COHERENT, a type of memory
owned by a device that can be mapped into CPU page tables like
MEMORY_DEVICE_GENERIC and can also be migrated like MEMORY_DEVICE_PRIVATE.
This patch series is mostly self-contained except for a few places where
it needs to update other subsystems to handle the new memory type.
System stability and performance are not affected according to our ongoing
testing, including xfstests.
How it works: The system BIOS advertises the GPU device memory (aka VRAM)
as SPM (special purpose memory) in the UEFI system address map.
The amdgpu driver registers the memory with devmap as
MEMORY_DEVICE_COHERENT using devm_memremap_pages. The initial user for
this hardware page migration capability is the Frontier supercomputer
project. This functionality is not AMD-specific. We expect other GPU
vendors to find this functionality useful, and possibly other hardware
types in the future.
Our test nodes in the lab are similar to the Frontier configuration, with
.5 TB of system memory plus 256 GB of device memory split across 4 GPUs,
all in a single coherent address space. Page migration is expected to
improve application efficiency significantly. We will report empirical
results as they become available.
Coherent device type pages at gup are now migrated back to system memory
if they are being pinned long-term (FOLL_LONGTERM). The reason is, that
long-term pinning would interfere with the device memory manager owning
the device-coherent pages (e.g. evictions in TTM). These series
incorporate Alistair Popple patches to do this migration from
pin_user_pages() calls. hmm_gup_test has been added to hmm-test to test
different get user pages calls.
This series includes handling of device-managed anonymous pages returned
by vm_normal_pages. Although they behave like normal pages for purposes
of mapping in CPU page tables and for COW, they do not support LRU lists,
NUMA migration or THP.
We also introduced a FOLL_LRU flag that adds the same behaviour to
follow_page and related APIs, to allow callers to specify that they expect
to put pages on an LRU list.
This patch (of 14):
is_pinnable_page() and folio_is_pinnable() are renamed to
is_longterm_pinnable_page() and folio_is_longterm_pinnable() respectively.
These functions are used in the FOLL_LONGTERM flag context.
Link: https://lkml.kernel.org/r/20220715150521.18165-1-alex.sierra@amd.com
Link: https://lkml.kernel.org/r/20220715150521.18165-2-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
damon_lru_sort_init() returns an error when damon_select_ops() fails
without freeing 'ctx' which allocated before. This commit fixes the
potential memory leak by freeing 'ctx' under the situation.
Link: https://lkml.kernel.org/r/20220714170458.49727-1-sj@kernel.org
Fixes: 40e983cca9 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Make KASAN run on User Mode Linux on x86_64.
The UML-specific KASAN initializer uses mmap to map the ~16TB of shadow
memory to the location defined by KASAN_SHADOW_OFFSET. kasan_init()
utilizes constructors to initialize KASAN before main().
The location of the KASAN shadow memory, starting at
KASAN_SHADOW_OFFSET, can be configured using the KASAN_SHADOW_OFFSET
option. The default location of this offset is 0x100000000000, which
keeps it out-of-the-way even on UML setups with more "physical" memory.
For low-memory setups, 0x7fff8000 can be used instead, which fits in an
immediate and is therefore faster, as suggested by Dmitry Vyukov. There
is usually enough free space at this location; however, it is a config
option so that it can be easily changed if needed.
Note that, unlike KASAN on other architectures, vmalloc allocations
still use the shadow memory allocated upfront, rather than allocating
and free-ing it per-vmalloc allocation.
If another architecture chooses to go down the same path, we should
replace the checks for CONFIG_UML with something more generic, such
as:
- A CONFIG_KASAN_NO_SHADOW_ALLOC option, which architectures could set
- or, a way of having architecture-specific versions of these vmalloc
and module shadow memory allocation options.
Also note that, while UML supports both KASAN in inline mode
(CONFIG_KASAN_INLINE) and static linking (CONFIG_STATIC_LINK), it does
not support both at the same time.
Signed-off-by: Patricia Alfonso <trishalfonso@google.com>
Co-developed-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Currently post_alloc_hook() skips the kasan unpoisoning if the tags will
be zeroed (__GFP_ZEROTAGS) or __GFP_SKIP_KASAN_UNPOISON is passed. Since
__GFP_ZEROTAGS is now accompanied by __GFP_SKIP_KASAN_UNPOISON, remove
the extra check.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-4-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Commit c275c5c6d5 ("kasan: disable freed user page poisoning with HW
tags") added __GFP_SKIP_KASAN_POISON to GFP_HIGHUSER_MOVABLE. A similar
argument can be made about unpoisoning, so also add
__GFP_SKIP_KASAN_UNPOISON to user pages. To ensure the user page is
still accessible via page_address() without a kasan fault, reset the
page->flags tag.
With the above changes, there is no need for the arm64
tag_clear_highpage() to reset the page->flags tag.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-3-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
__kasan_unpoison_pages() colours the memory with a random tag and stores
it in page->flags in order to re-create the tagged pointer via
page_to_virt() later. When the tag from the page->flags is read, ensure
that the in-memory tags are already visible by re-ordering the
page_kasan_tag_set() after kasan_unpoison(). The former already has
barriers in place through try_cmpxchg(). On the reader side, the order
is ensured by the address dependency between page->flags and the memory
access.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-2-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Most callers of memcg_slab_free_hook() already know the slab, which could
be passed to memcg_slab_free_hook() directly to reduce the overhead of an
another call of virt_to_slab(). For bulk freeing of objects, the call of
slab_objcgs() in the loop in memcg_slab_free_hook() is redundant as well.
Rework memcg_slab_free_hook() and build_detached_freelist() to reduce
those unnecessary overhead and make memcg_slab_free_hook() can handle bulk
freeing in slab_free().
Move the calling site of memcg_slab_free_hook() from do_slab_free() to
slab_free() for slub to make the code clearer since the logic is weird
(e.g. the caller need to judge whether it needs to call
memcg_slab_free_hook()). It is easy to make mistakes like missing calling
of memcg_slab_free_hook() like fixes of:
commit d1b2cf6cb8 ("mm: memcg/slab: uncharge during kmem_cache_free_bulk()")
commit ae085d7f93 ("mm: kfence: fix missing objcg housekeeping for SLAB")
This optimization is mainly for bulk objects freeing. The following numbers
is shown for 16-object freeing.
before after
kmem_cache_free_bulk: ~430 ns ~400 ns
The overhead is reduced by about 7% for 16-object freeing.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Link: https://lore.kernel.org/r/20220429123044.37885-1-songmuchun@bytedance.com
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Slab caches marked with SLAB_ACCOUNT force accounting for every
allocation from this cache even if __GFP_ACCOUNT flag is not passed.
Unfortunately, at the moment this flag is not visible in ftrace output,
and this makes it difficult to analyze the accounted allocations.
This patch adds boolean "accounted" entry into trace output,
and set it to 'true' for calls used __GFP_ACCOUNT flag and
for allocations from caches marked with SLAB_ACCOUNT.
Set it to 'false' if accounting is disabled in configs.
Signed-off-by: Vasily Averin <vvs@openvz.org>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Link: https://lore.kernel.org/r/c418ed25-65fe-f623-fbf8-1676528859ed@openvz.org
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
There is no need to do anything if sysfs_slab_alias() return nonzero
value after getting a mergeable cache.
Signed-off-by: Xiongwei Song <xiongwei.song@windriver.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Link: https://lore.kernel.org/all/e5ebc952-af17-321f-5343-bc914d47c931@suse.cz/
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
As reported by coccicheck:
./mm/slab.c:3253:2-59: code aligned with following code on line 3255.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Transhuge swapcaches won't be freed in __collapse_huge_page_copy(). It's
because release_pte_page() is not called for these pages and thus
free_page_and_swap_cache can't grab the page lock. These pages won't be
freed from swap cache even if we are the only user until next time
reclaim. It shouldn't hurt indeed, but we could try to free these pages
to save more memory for system.
Link: https://lkml.kernel.org/r/20220625092816.4856-8-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The return value of khugepaged_add_pte_mapped_thp() is always 0 and also
ignored. Remove it to clean up the code.
Link: https://lkml.kernel.org/r/20220625092816.4856-7-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
nr_none is always 0 for non-shmem case because the page can be read from
the backend store. So when nr_none ! = 0, it must be in is_shmem case.
Also only adjust the nrpages and uncharge shmem when nr_none != 0 to save
cpu cycles.
Link: https://lkml.kernel.org/r/20220625092816.4856-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix some typos and tweak the code to meet codestyle. No functional change
intended.
Link: https://lkml.kernel.org/r/20220625092816.4856-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When do_swap_page returns VM_FAULT_RETRY, we do not retry here and thus
swap entry will remain in pagetable. This will result in later failure.
So stop swapping in pages in this case to save cpu cycles. As A further
optimization, mmap_lock is released when __collapse_huge_page_swapin()
fails to avoid relocking mmap_lock. And "swapped_in++" is moved after
error handling to make it more accurate.
Link: https://lkml.kernel.org/r/20220625092816.4856-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "A few cleanup patches for khugepaged", v2.
This series contains a few cleaup patches to remove unneeded return value,
use helper macro, fix typos and so on. More details can be found in the
respective changelogs.
This patch (of 7):
If we reach here, khugepaged_scan_mm_slot() has already made sure that
hugepage is enabled for shmem, via its call to hugepage_vma_check().
Remove this duplicated check.
Link: https://lkml.kernel.org/r/20220625092816.4856-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220625092816.4856-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zach O'Keefe <zokeefe@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Howells <dhowells@redhat.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit e5251fd430 ("mm/hugetlb: introduce set_huge_swap_pte_at()
helper") add set_huge_swap_pte_at() to handle swap entries on
architectures that support hugepages consisting of contiguous ptes. And
currently the set_huge_swap_pte_at() is only overridden by arm64.
set_huge_swap_pte_at() provide a sz parameter to help determine the number
of entries to be updated. But in fact, all hugetlb swap entries contain
pfn information, so we can find the corresponding folio through the pfn
recorded in the swap entry, then the folio_size() is the number of entries
that need to be updated.
And considering that users will easily cause bugs by ignoring the
difference between set_huge_swap_pte_at() and set_huge_pte_at(). Let's
handle swap entries in set_huge_pte_at() and remove the
set_huge_swap_pte_at(), then we can call set_huge_pte_at() anywhere, which
simplifies our coding.
Link: https://lkml.kernel.org/r/20220626145717.53572-1-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Not all systems use swap, so estimating available memory would help to
prevent swapping or OOM of system that not use swap.
And we need to reserve some page cache to prevent swapping or thrashing.
If somebody is accessing the pages in pagecache, and if too much would be
freed, most accesses might mean reading data from disk, i.e. thrashing.
Link: https://lkml.kernel.org/r/20220623020833.972979-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: CGEL ZTE <cgel.zte@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Comments that mention mem_hotplug_end() are confusing as there is no
function called mem_hotplug_end(). Fix them by replacing all the
occurences of mem_hotplug_end() in the comments with mem_hotplug_done().
[akpm@linux-foundation.org: grammatical fixes]
Link: https://lkml.kernel.org/r/20220620071516.1286101-1-p76091292@gs.ncku.edu.tw
Signed-off-by: Yun-Ze Li <p76091292@gs.ncku.edu.tw>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Passing index to pte_offset_map_lock() directly so the below calculation
can be avoided. Rename orig_pte to ptep as it's not changed. Also use
helper is_swap_pte() to improve the readability. No functional change
intended.
[akpm@linux-foundation.org: reduce scope of `ptep']
Link: https://lkml.kernel.org/r/20220618090527.37843-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit 641844f561 ("mm/hugetlb: introduce minimum hugepage order") fixed
a static checker warning and introduced a global variable minimum_order to
fix the warning. However, the local variable in
dissolve_free_huge_pages() can be initialized to
huge_page_order(&default_hstate) to fix the warning.
So remove minimum_order to simplify the code.
Link: https://lkml.kernel.org/r/20220616033846.96937-1-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
For now, the feature of hugetlb_free_vmemmap is not compatible with the
feature of memory_hotplug.memmap_on_memory, and hugetlb_free_vmemmap takes
precedence over memory_hotplug.memmap_on_memory. However, someone wants
to make memory_hotplug.memmap_on_memory takes precedence over
hugetlb_free_vmemmap since memmap_on_memory makes it more likely to
succeed memory hotplug in close-to-OOM situations. So the decision of
making hugetlb_free_vmemmap take precedence is not wise and elegant.
The proper approach is to have hugetlb_vmemmap.c do the check whether the
section which the HugeTLB pages belong to can be optimized. If the
section's vmemmap pages are allocated from the added memory block itself,
hugetlb_free_vmemmap should refuse to optimize the vmemmap, otherwise, do
the optimization. Then both kernel parameters are compatible. So this
patch introduces VmemmapSelfHosted to mask any non-optimizable vmemmap
pages. The hugetlb_vmemmap can use this flag to detect if a vmemmap page
can be optimized.
[songmuchun@bytedance.com: walk vmemmap page tables to avoid false-positive]
Link: https://lkml.kernel.org/r/20220620110616.12056-3-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20220617135650.74901-3-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Co-developed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "make hugetlb_optimize_vmemmap compatible with
memmap_on_memory", v3.
This series makes hugetlb_optimize_vmemmap compatible with
memmap_on_memory.
This patch (of 2):
We are almost running out of section flags, only one bit is available in
the worst case (powerpc with 256k pages). However, there are still some
free bits (in ->section_mem_map) on other architectures (e.g. x86_64 has
10 bits available, arm64 has 8 bits available with worst case of 64K
pages). We have hard coded those numbers in code, it is inconvenient to
use those bits on other architectures except powerpc. So transfer those
section flags to enumeration to make it easy to add new section flags in
the future. Also, move SECTION_TAINT_ZONE_DEVICE into the scope of
CONFIG_ZONE_DEVICE to save a bit on non-zone-device case.
[songmuchun@bytedance.com: replace enum with defines per David]
Link: https://lkml.kernel.org/r/20220620110616.12056-2-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20220617135650.74901-1-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20220617135650.74901-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The only caller already has a folio, so push the folio->page conversion
down a level.
Link: https://lkml.kernel.org/r/20220617175020.717127-21-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All callers now have a folio, so push the folio->page conversion
down to this function.
[akpm@linux-foundation.org: uninline destroy_large_folio() to fix build issue]
Link: https://lkml.kernel.org/r/20220617175020.717127-20-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All the callers now have a folio. Saves several calls to compound_head,
totalling 502 bytes of text.
Link: https://lkml.kernel.org/r/20220617175020.717127-19-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All the callers now have a folio, so pass it in. This doesn't
save any text, but it does save a call to compound_head() as
folio_test_hugetlb() does not contain a call like PageHuge() does.
Link: https://lkml.kernel.org/r/20220617175020.717127-18-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pages linked through the LRU list cannot be tail pages as ->compound_head
is in a union with one of the words of the list_head, and they cannot
be ZONE_DEVICE pages as ->pgmap is in a union with the same word.
Saves 60 bytes of text by removing a call to page_is_fake_head().
Link: https://lkml.kernel.org/r/20220617175020.717127-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This function was already calling compound_head(), but now it can
cache the result of calling compound_head() and avoid calling it again.
Saves 299 bytes of text by avoiding various calls to compound_page()
and avoiding checks of PageTail.
Link: https://lkml.kernel.org/r/20220617175020.717127-14-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Save a few calls to compound_head by converting the passed page to
a folio. Reduces kernel text size by 74 bytes.
Link: https://lkml.kernel.org/r/20220617175020.717127-13-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Do the per-cpu dereferencing of the fbatches once which saves 14 bytes
of text and several percpu relocations.
Link: https://lkml.kernel.org/r/20220617175020.717127-12-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The function is too long, so pull this complicated conditional out into
cpu_needs_drain(). This ends up shrinking the text by 14 bytes,
by allowing GCC to cache the result of calling per_cpu() instead of
relocating each lookup individually.
Link: https://lkml.kernel.org/r/20220617175020.717127-11-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
No change to generated code, but this struct no longer contains any
pagevecs, and not all the folio batches it contains are lru.
Link: https://lkml.kernel.org/r/20220617175020.717127-10-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename it to just 'activate', saving 696 bytes of text from removals
of compound_page() and the pagevec_lru_move_fn() infrastructure.
Inline need_activate_page_drain() into its only caller.
Link: https://lkml.kernel.org/r/20220617175020.717127-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Using folios instead of pages removes several calls to compound_head(),
shrinking the kernel by 1089 bytes of text.
Link: https://lkml.kernel.org/r/20220617175020.717127-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Using folios instead of pages shrinks deactivate_page() and
lru_deactivate_fn() by 778 bytes between them.
Link: https://lkml.kernel.org/r/20220617175020.717127-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use a folio throughout lru_deactivate_file_fn(), removing many hidden
calls to compound_head(). Shrinks the kernel by 864 bytes of text.
Link: https://lkml.kernel.org/r/20220617175020.717127-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When adding folios to the LRU for the first time, the LRU flag will
already be clear, so skip the test-and-clear part of moving from one
LRU to another.
Removes 285 bytes from kernel text, mostly due to removing
__pagevec_lru_add().
Link: https://lkml.kernel.org/r/20220617175020.717127-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__pagevec_lru_add has no callers outside swap.c, so make it static,
and move it to a more logical position in the file.
Link: https://lkml.kernel.org/r/20220617175020.717127-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Start converting the LRU from pagevecs to folio_batches.
Combine the functionality of pagevec_add_and_need_flush() with
pagevec_lru_move_fn() in the new folio_batch_add_and_move().
Convert the lru_rotate pagevec to a folio_batch.
Adds 223 bytes total to kernel text, because we're duplicating
infrastructure. This will be more than made up for in future patches.
Link: https://lkml.kernel.org/r/20220617175020.717127-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove a few hidden calls to compound_head, saving 76 bytes of text.
Link: https://lkml.kernel.org/r/20220617154248.700416-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove a few hidden calls to compound_head, saving 411 bytes of text.
Link: https://lkml.kernel.org/r/20220617154248.700416-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove a few hidden calls to compound_head, saving 387 bytes of text on
my test configuration.
Link: https://lkml.kernel.org/r/20220617154248.700416-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove a few hidden calls to compound_head, saving 279 bytes of text.
Link: https://lkml.kernel.org/r/20220617154248.700416-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "nvert much of vmscan to folios"
vmscan always operates on folios since it puts the pages on the LRU list.
Switching all of these functions from pages to folios saves 1483 bytes of
text from removing all the baggage around calling compound_page() and
similar functions.
This patch (of 5):
This is a straightforward conversion which removes several hidden calls
to compound_head, saving 330 bytes of kernel text.
Link: https://lkml.kernel.org/r/20220617154248.700416-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20220617154248.700416-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Similar to our MM_CP_DIRTY_ACCT handling for shared, writable mappings, we
can try mapping anonymous pages in a private writable mapping writable if
they are exclusive, the PTE is already dirty, and no special handling
applies. Mapping the anonymous page writable is essentially the same
thing the write fault handler would do in this case.
Special handling is required for uffd-wp and softdirty tracking, so take
care of that properly. Also, leave PROT_NONE handling alone for now; in
the future, we could similarly extend the logic in do_numa_page() or use
pte_mk_savedwrite() here.
While this improves mprotect(PROT_READ)+mprotect(PROT_READ|PROT_WRITE)
performance, it should also be a valuable optimization for uffd-wp, when
un-protecting.
This has been previously suggested by Peter Collingbourne in [1], relevant
in the context of the Scudo memory allocator, before we had
PageAnonExclusive.
This commit doesn't add the same handling for PMDs (i.e., anonymous THP,
anonymous hugetlb); benchmark results from Andrea indicate that there are
minor performance gains, so it's might still be valuable to streamline
that logic for all anonymous pages in the future.
As we now also set MM_CP_DIRTY_ACCT for private mappings, let's rename it
to MM_CP_TRY_CHANGE_WRITABLE, to make it clearer what's actually
happening.
Micro-benchmark courtesy of Andrea:
===
#define _GNU_SOURCE
#include <sys/mman.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#define SIZE (1024*1024*1024)
int main(int argc, char *argv[])
{
char *p;
if (posix_memalign((void **)&p, sysconf(_SC_PAGESIZE)*512, SIZE))
perror("posix_memalign"), exit(1);
if (madvise(p, SIZE, argc > 1 ? MADV_HUGEPAGE : MADV_NOHUGEPAGE))
perror("madvise");
explicit_bzero(p, SIZE);
for (int loops = 0; loops < 40; loops++) {
if (mprotect(p, SIZE, PROT_READ))
perror("mprotect"), exit(1);
if (mprotect(p, SIZE, PROT_READ|PROT_WRITE))
perror("mprotect"), exit(1);
explicit_bzero(p, SIZE);
}
}
===
Results on my Ryzen 9 3900X:
Stock 10 runs (lower is better): AVG 6.398s, STDEV 0.043
Patched 10 runs (lower is better): AVG 3.780s, STDEV 0.026
===
[1] https://lkml.kernel.org/r/20210429214801.2583336-1-pcc@google.com
Link: https://lkml.kernel.org/r/20220614093629.76309-1-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Peter Collingbourne <pcc@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Users can do data access-aware LRU-lists sorting using 'LRU_PRIO' and
'LRU_DEPRIO' DAMOS actions. However, finding best parameters including
the hotness/coldness thresholds, CPU quota, and watermarks could be
challenging for some users. To make the scheme easy to be used without
complex tuning for common situations, this commit implements a static
kernel module called 'DAMON_LRU_SORT' using the 'LRU_PRIO' and
'LRU_DEPRIO' DAMOS actions.
It proactively sorts LRU-lists using DAMON with conservatively chosen
default values of the parameters. That is, the module under its default
parameters will make no harm for common situations but provide some level
of efficiency improvements for systems having clear hot/cold access
pattern under a level of memory pressure while consuming only a limited
small portion of CPU time.
Link: https://lkml.kernel.org/r/20220613192301.8817-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit adds a new DAMON-based operation scheme action called
'LRU_DEPRIO' for physical address space. The action deprioritizes pages
in the memory area of the target access pattern on their LRU lists. This
is hence supposed to be used for rarely accessed (cold) memory regions so
that cold pages could be more likely reclaimed first under memory
pressure. Internally, it simply calls 'lru_deactivate()'.
Using this with 'LRU_PRIO' action for hot pages, users can proactively
sort LRU lists based on the access pattern. That is, it can make the LRU
lists somewhat more trustworthy source of access temperature. As a
result, efficiency of LRU-lists based mechanisms including the reclamation
target selection could be improved.
Link: https://lkml.kernel.org/r/20220613192301.8817-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit adds a new DAMOS action called 'LRU_PRIO' for the physical
address space. The action prioritizes pages in the memory regions of the
user-specified target access pattern on their LRU lists. This is hence
supposed to be used for frequently accessed (hot) memory regions so that
hot pages could be more likely protected under memory pressure.
Internally, it simply calls 'mark_page_accessed()'.
Link: https://lkml.kernel.org/r/20220613192301.8817-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit moves code for 'DAMOS_PAGEOUT' handling of the physical
address space monitoring operations set to a separate function so that its
caller, 'damon_pa_apply_scheme()', can be more easily extended for
additional DAMOS actions later.
Link: https://lkml.kernel.org/r/20220613192301.8817-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Extend DAMOS for Proactive LRU-lists Sorting".
Introduction
============
In short, this patchset 1) extends DAMON-based Operation Schemes (DAMOS)
for low overhead data access pattern based LRU-lists sorting, and 2)
implements a static kernel module for easy use of conservatively-tuned
version of that using the extended DAMOS capability.
Background
----------
As page-granularity access checking overhead could be significant on huge
systems, LRU lists are normally not proactively sorted but partially and
reactively sorted for special events including specific user requests,
system calls and memory pressure. As a result, LRU lists are sometimes
not so perfectly prepared to be used as a trustworthy access pattern
source for some situations including reclamation target pages selection
under sudden memory pressure.
DAMON-based Proactive LRU-lists Sorting
---------------------------------------
Because DAMON can identify access patterns of best-effort accuracy while
inducing only user-specified range of overhead, using DAMON for Proactive
LRU-lists Sorting (PLRUS) could be helpful for this situation. The idea
is quite simple. Find hot pages and cold pages using DAMON, and
prioritize hot pages while deprioritizing cold pages on their LRU-lists.
This patchset extends DAMON to support such schemes by introducing a
couple of new DAMOS actions for prioritizing and deprioritizing memory
regions of specific access patterns on their LRU-lists. In detail, this
patchset simply uses 'mark_page_accessed()' and 'deactivate_page()'
functions for prioritization and deprioritization of pages on their LRU
lists, respectively.
To make the scheme easy to use without complex tuning for common
situations, this patchset further implements a static kernel module called
'DAMON_LRU_SORT' using the extended DAMOS functionality. It proactively
sorts LRU-lists using DAMON with conservatively chosen default
hotness/coldness thresholds and small CPU usage quota limit. That is, the
module under its default parameters will make no harm for common situation
but provide some level of benefit for systems having clear hot/cold access
pattern under only memory pressure while consuming only limited small
portion of CPU time.
Related Works
-------------
Proactive reclamation is well known to be helpful for reducing non-optimal
reclamation target selection caused performance drops. However, proactive
reclamation is not a best option for some cases, because it could incur
additional I/O. For an example, it could be prohitive for systems using
storage devices that total number of writes is limited, or cloud block
storages that charges every I/O.
Some proactive reclamation approaches[1,2] induce a level of memory
pressure using memcg files or swappiness while monitoring PSI. As
reclamation target selection is still relying on the original LRU-lists
mechanism, using DAMON-based proactive reclamation before inducing the
proactive reclamation could allow more memory saving with same level of
performance overhead, or less performance overhead with same level of
memory saving.
[1] https://blogs.oracle.com/linux/post/anticipating-your-memory-needs
[2] https://www.pdl.cmu.edu/ftp/NVM/tmo_asplos22.pdf
Evaluation
==========
In short, PLRUS achieves 10% memory PSI (some) reduction, 14% major page
faults reduction, and 3.74% speedup under memory pressure.
Setup
-----
To show the effect of PLRUS, I run PARSEC3 and SPLASH-2X benchmarks under
below variant systems and measure a few metrics including the runtime of
each workload, number of system-wide major page faults, and system-wide
memory PSI (some).
- orig: v5.18-rc4 based mm-unstable kernel + this patchset, but no DAMON scheme
applied.
- mprs: Same to 'orig' but artificial memory pressure is induced.
- plrus: Same to 'mprs' but a radically tuned PLRUS scheme is applied to the
entire physical address space of the system.
For the artificial memory pressure, I set 'memory.limit_in_bytes' to 75%
of the running workload's peak RSS, wait 1 second, remove the pressure by
setting it to 200% of the peak RSS, wait 10 seconds, and repeat the
procedure until the workload finishes[1]. I use zram based swap device.
The tests are automated[2].
[1] https://github.com/awslabs/damon-tests/blob/next/perf/runners/back/0009_memcg_pressure.sh
[2] https://github.com/awslabs/damon-tests/blob/next/perf/full_once_config.sh
Radically Tuned PLRUS
---------------------
To show effect of PLRUS on the PARSEC3/SPLASH-2X workloads which runs for
no long time, we use radically tuned version of PLRUS. The version asks
DAMON to do the proactive LRU-lists sorting as below.
1. Find any memory regions shown some accesses (approximately >=20 accesses per
100 sampling) and prioritize pages of the regions on their LRU lists using
up to 2% CPU time. Under the CPU time limit, prioritize regions having
higher access frequency and kept the access frequency longer first.
2. Find any memory regions shown no access for at least >=5 seconds and
deprioritize pages of the rgions on their LRU lists using up to 2% CPU time.
Under the CPU time limit, deprioritize regions that not accessed for longer
time first.
Results
-------
I repeat the tests 25 times and calculate average of the measured numbers.
The results are as below:
metric orig mprs plrus plrus/mprs
runtime_seconds 190.06 292.83 281.87 0.96
pgmajfaults 852.55 8769420.00 7525040.00 0.86
memory_psi_some_us 106911.00 6943420.00 6220920.00 0.90
The first row is for legend. The first cell shows the metric that the
following cells of the row shows. Second, third, and fourth cells show
the metrics under the configs shown at the first row of the cell, and the
fifth cell shows the metric under 'plrus' divided by the metric under
'mprs'. Second row shows the averaged runtime of the workloads in
seconds. Third row shows the number of system-wide major page faults
while the test was ongoing. Fourth row shows the system-wide memory
pressure stall for some processes in microseconds while the test was
ongoing.
In short, PLRUS achieves 10% memory PSI (some) reduction, 14% major page
faults reduction, and 3.74% speedup under memory pressure. We also
confirmed the CPU usage of kdamond was 2.61% of single CPU, which is below
4% as expected.
Sequence of Patches
===================
The first and second patch cleans up DAMON debugfs interface and
DAMOS_PAGEOUT handling code of physical address space monitoring
operations implementation for easier extension of the code.
The thrid and fourth patches implement a new DAMOS action called
'lru_prio', which prioritizes pages under memory regions which have a
user-specified access pattern, and document it, respectively. The fifth
and sixth patches implement yet another new DAMOS action called
'lru_deprio', which deprioritizes pages under memory regions which have a
user-specified access pattern, and document it, respectively.
The seventh patch implements a static kernel module called
'damon_lru_sort', which utilizes the DAMON-based proactive LRU-lists
sorting under conservatively chosen default parameter. Finally, the
eighth patch documents 'damon_lru_sort'.
This patch (of 8):
DAMON debugfs interface assumes users will write 'damos_action' value
directly to the 'schemes' file. This makes adding new 'damos_action' in
the middle of its definition breaks the backward compatibility of DAMON
debugfs interface, as values of some 'damos_action' could be changed. To
mitigate the situation, this commit adds mappings between the user inputs
and 'damos_action' value and makes DAMON debugfs code uses those.
Link: https://lkml.kernel.org/r/20220613192301.8817-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220613192301.8817-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
swap_cache_info are not statistics that could be easily used to tune
system performance because they are not easily accessile. Also they can't
provide really useful info when OOM occurs. Remove these statistics can
also help mitigate unneeded global swap_cache_info cacheline contention.
Link: https://lkml.kernel.org/r/20220608144031.829-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
si->inuse_pages could still be accessed concurrently now. The plain reads
outside si->lock critical section, i.e. swap_show and si_swapinfo, which
results in data races. READ_ONCE and WRITE_ONCE is used to fix such data
races. Note these data races should be ok because they're just used for
showing swap info.
[linmiaohe@huawei.com: use WRITE_ONCE to pair with READ_ONCE]
Link: https://lkml.kernel.org/r/20220625093346.48894-2-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220608144031.829-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__find_vmap_area() finds a "vmap_area" based on passed address. It scan
the specific "vmap_area_root" rb-tree. Extend the function with one extra
argument, so any tree can be specified where the search has to be done.
There is no functional change as a result of this patch.
Link: https://lkml.kernel.org/r/20220607093449.3100-5-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A vmap_area can travel between different places. For example
attached/detached to/from different rb-trees. In order to prevent fancy
bugs, initialize a VA's list node after it is removed from the list, so it
pairs with VA's rb_node which is also initialized.
There is no functional change as a result of this patch.
Link: https://lkml.kernel.org/r/20220607093449.3100-4-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It implies that __alloc_vmap_area() allocates only from the global vmap
space, therefore a list-head and rb-tree, which represent a free vmap
space, are not passed as parameters to this function and are accessed
directly from this function.
Extend the __alloc_vmap_area() and other dependent functions to have a
possibility to allocate from different trees making an interface common
and not specific.
There is no functional change as a result of this patch.
Link: https://lkml.kernel.org/r/20220607093449.3100-3-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Reduce a vmalloc internal lock contention preparation work".
This small serias is preparation work to implement per-cpu vmalloc
allocation in order to reduce a high internal lock contention. This
series does not introduce any functional changes, it is only about
preparation.
This patch (of 5):
Currently link_va() and unlik_va(), in order to figure out a tree type,
compares a passed root value with a global free_vmap_area_root variable to
distinguish the augmented rb-tree from a regular one. It is hard coded
since such functions can manipulate only with specific
"free_vmap_area_root" tree that represents a global free vmap space.
Make it common by introducing "_augment" versions of both internal
functions, so it is possible to deal with different trees.
There is no functional change as a result of this patch.
Link: https://lkml.kernel.org/r/20220607093449.3100-1-urezki@gmail.com
Link: https://lkml.kernel.org/r/20220607093449.3100-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a scan interface which allows to trigger scanning of a particular
shrinker and specify memcg and numa node. It's useful for testing,
debugging and profiling of a specific scan_objects() callback. Unlike
alternatives (creating a real memory pressure and dropping caches via
/proc/sys/vm/drop_caches) this interface allows to interact with only one
shrinker at once. Also, if a shrinker is misreporting the number of
objects (as some do), it doesn't affect scanning.
[roman.gushchin@linux.dev: improve typing, fix arg count checking]
Link: https://lkml.kernel.org/r/YpgKttTowT22mKPQ@carbon
[akpm@linux-foundation.org: fix arg count checking]
Link: https://lkml.kernel.org/r/20220601032227.4076670-7-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently shrinkers are anonymous objects. For debugging purposes they
can be identified by count/scan function names, but it's not always
useful: e.g. for superblock's shrinkers it's nice to have at least an
idea of to which superblock the shrinker belongs.
This commit adds names to shrinkers. register_shrinker() and
prealloc_shrinker() functions are extended to take a format and arguments
to master a name.
In some cases it's not possible to determine a good name at the time when
a shrinker is allocated. For such cases shrinker_debugfs_rename() is
provided.
The expected format is:
<subsystem>-<shrinker_type>[:<instance>]-<id>
For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair.
After this change the shrinker debugfs directory looks like:
$ cd /sys/kernel/debug/shrinker/
$ ls
dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42
mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43
mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44
rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49
sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13
sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36
sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19
sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10
sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9
sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37
sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38
sb-dax-11 sb-proc-45 sb-tmpfs-35
sb-debugfs-7 sb-proc-46 sb-tmpfs-40
[roman.gushchin@linux.dev: fix build warnings]
Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit introduces the /sys/kernel/debug/shrinker debugfs interface
which provides an ability to observe the state of individual kernel memory
shrinkers.
Because the feature adds some memory overhead (which shouldn't be large
unless there is a huge amount of registered shrinkers), it's guarded by a
config option (enabled by default).
This commit introduces the "count" interface for each shrinker registered
in the system.
The output is in the following format:
<cgroup inode id> <nr of objects on node 0> <nr of objects on node 1>...
<cgroup inode id> <nr of objects on node 0> <nr of objects on node 1>...
...
To reduce the size of output on machines with many thousands cgroups, if
the total number of objects on all nodes is 0, the line is omitted.
If the shrinker is not memcg-aware or CONFIG_MEMCG is off, 0 is printed as
cgroup inode id. If the shrinker is not numa-aware, 0's are printed for
all nodes except the first one.
This commit gives debugfs entries simple numeric names, which are not very
convenient. The following commit in the series will provide shrinkers
with more meaningful names.
[akpm@linux-foundation.org: remove WARN_ON_ONCE(), per Roman]
Reported-by: syzbot+300d27c79fe6d4cbcc39@syzkaller.appspotmail.com
Link: https://lkml.kernel.org/r/20220601032227.4076670-3-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm: introduce shrinker debugfs interface", v5.
The only existing debugging mechanism is a couple of tracepoints in
do_shrink_slab(): mm_shrink_slab_start and mm_shrink_slab_end. They
aren't covering everything though: shrinkers which report 0 objects will
never show up, there is no support for memcg-aware shrinkers. Shrinkers
are identified by their scan function, which is not always enough (e.g.
hard to guess which super block's shrinker it is having only
"super_cache_scan").
To provide a better visibility and debug options for memory shrinkers this
patchset introduces a /sys/kernel/debug/shrinker interface, to some extent
similar to /sys/kernel/slab.
For each shrinker registered in the system a directory is created. As
now, the directory will contain only a "scan" file, which allows to get
the number of managed objects for each memory cgroup (for memcg-aware
shrinkers) and each numa node (for numa-aware shrinkers on a numa
machine). Other interfaces might be added in the future.
To make debugging more pleasant, the patchset also names all shrinkers, so
that debugfs entries can have meaningful names.
This patch (of 5):
Shrinker debugfs requires a way to represent memory cgroups without using
full paths, both for displaying information and getting input from a user.
Cgroup inode number is a perfect way, already used by bpf.
This commit adds a couple of helper functions which will be used to handle
memcg-aware shrinkers.
Link: https://lkml.kernel.org/r/20220601032227.4076670-1-roman.gushchin@linux.dev
Link: https://lkml.kernel.org/r/20220601032227.4076670-2-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When user specified more nodes than supported, get_nodes will access nmask
array out of bounds.
Link: https://lkml.kernel.org/r/20220601093211.2970565-1-tianyu.li@arm.com
Fixes: e130242dc3 ("mm: simplify compat numa syscalls")
Signed-off-by: Tianyu Li <tianyu.li@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There is no need to update the hugetlb access flags after just setting the
hugetlb page table entry by set_huge_pte_at(), since the page table entry
value has no changes.
Thus remove the unnecessary huge_ptep_set_access_flags() in
hugetlb_mcopy_atomic_pte().
Link: https://lkml.kernel.org/r/f3e28b897b53a69967a8b98a6fdcda3be80c9229.1653616175.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
HW_TAGS KASAN skips zeroing page_alloc allocations backing vmalloc
mappings via __GFP_SKIP_ZERO. Instead, these pages are zeroed via
kasan_unpoison_vmalloc() by passing the KASAN_VMALLOC_INIT flag.
The problem is that __kasan_unpoison_vmalloc() does not zero pages when
either kasan_vmalloc_enabled() or is_vmalloc_or_module_addr() fail.
Thus:
1. Change __vmalloc_node_range() to only set KASAN_VMALLOC_INIT when
__GFP_SKIP_ZERO is set.
2. Change __kasan_unpoison_vmalloc() to always zero pages when the
KASAN_VMALLOC_INIT flag is set.
3. Add WARN_ON() asserts to check that KASAN_VMALLOC_INIT cannot be set
in other early return paths of __kasan_unpoison_vmalloc().
Also clean up the comment in __kasan_unpoison_vmalloc.
Link: https://lkml.kernel.org/r/4bc503537efdc539ffc3f461c1b70162eea31cf6.1654798516.git.andreyknvl@google.com
Fixes: 23689e91fb ("kasan, vmalloc: add vmalloc tagging for HW_TAGS")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a clear_highpage_kasan_tagged() helper that does clear_highpage() on a
page potentially tagged by KASAN.
This helper is used by the following patch.
Link: https://lkml.kernel.org/r/4471979b46b2c487787ddcd08b9dc5fedd1b6ffd.1654798516.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename kernel_init_free_pages() to kernel_init_pages(). This function is
not only used for free pages but also for pages that were just allocated.
Link: https://lkml.kernel.org/r/1ecaffc0a9c1404d4d7cf52efe0b2dc8a0c681d8.1654798516.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit adds 'damon_reclaim_' prefix to 'enabled_store()', so that we
can distinguish it easily from the stack trace using 'faddr2line.sh' like
tools.
Link: https://lkml.kernel.org/r/20220606182310.48781-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON_RECLAIM's 'enabled' parameter store callback ('enabled_store()')
schedules the parameter check timer ('damon_reclaim_timer') if the
parameter is set as 'Y'. Then, the timer schedules itself to check if
user has set the parameter as 'N'. It's unnecessarily complex.
This commit makes it simpler by making the parameter store callback to
schedule the timer regardless of the parameter value and disabling the
timer's self scheduling.
Link: https://lkml.kernel.org/r/20220606182310.48781-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON sysfs interface's DAMON context building and its online parameter
update have duplicated code. This commit removes the duplicate.
Link: https://lkml.kernel.org/r/20220606182310.48781-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON_RECLAIM's handling of 'commit_inputs' parameter is duplicated in
'after_aggregation()' and 'after_wmarks_check()' callbacks. This commit
deduplicates the code for better maintenance.
Link: https://lkml.kernel.org/r/20220606182310.48781-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The function for knowing if given monitoring context's targets will have
pid or not is defined and used in dbgfs only. However, the logic is also
needed for sysfs. This commit moves the code to damon.h and makes both
dbgfs and sysfs to use it.
Link: https://lkml.kernel.org/r/20220606182310.48781-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__migration_entry_wait and migration_entry_wait_on_locked assume pte is
always mapped from caller. But this is not the case when it's called from
migration_entry_wait_huge and follow_huge_pmd. Add a hugetlbfs variant
that calls hugetlb_migration_entry_wait(ptep == NULL) to fix this issue.
Link: https://lkml.kernel.org/r/20220530113016.16663-5-linmiaohe@huawei.com
Fixes: 30dad30922 ("mm: migration: add migrate_entry_wait_huge()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We might fail to isolate huge page due to e.g. the page is under
migration which cleared HPageMigratable. We should return errno in this
case rather than always return 1 which could confuse the user, i.e. the
caller might think all of the memory is migrated while the hugetlb page is
left behind. We make the prototype of isolate_huge_page consistent with
isolate_lru_page as suggested by Huang Ying and rename isolate_huge_page
to isolate_hugetlb as suggested by Muchun to improve the readability.
Link: https://lkml.kernel.org/r/20220530113016.16663-4-linmiaohe@huawei.com
Fixes: e8db67eb0d ("mm: migrate: move_pages() supports thp migration")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Huang Ying <ying.huang@intel.com>
Reported-by: kernel test robot <lkp@intel.com> (build error)
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When non-lru movable page was freed from under us, __ClearPageMovable must
have been done. So we can remove unneeded lock page and PageMovable check
here. Also free_pages_prepare() will clear PG_isolated for us, so we can
further remove ClearPageIsolated as suggested by David.
Link: https://lkml.kernel.org/r/20220530113016.16663-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
IIUC page_vma_mapped_walk() checks if the vma is possibly huge PMD mapped
with transparent_hugepage_active() and "pvmw->nr_pages >= HPAGE_PMD_NR".
Actually pvmw->nr_pages is returned by compound_nr() or folio_nr_pages(),
so the page should be THP as long as "pvmw->nr_pages >= HPAGE_PMD_NR".
And it is guaranteed THP is allocated for valid VMA in the first place.
But it may be not PMD mapped if the VMA is file VMA and it is not properly
aligned. The transhuge_vma_suitable() is used to do such check, so
replace transparent_hugepage_active() to it, which is too heavy and
overkilling.
Link: https://lkml.kernel.org/r/20220513191705.457775-1-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently the implementation will split the PUD when a fallback is taken
inside the create_huge_pud function. This isn't where it should be done:
the splitting should be done in wp_huge_pud, just like it's done for PMDs.
Reason being that if a callback is taken during create, there is no PUD
yet so nothing to split, whereas if a fallback is taken when encountering
a write protection fault there is something to split.
It looks like this was the original intention with the commit where the
splitting was introduced, but somehow it got moved to the wrong place
between v1 and v2 of the patch series. Rebase mistake perhaps.
Link: https://lkml.kernel.org/r/6f48d622eb8bce1ae5dd75327b0b73894a2ec407.camel@amazon.com
Fixes: 327e9fd489 ("mm: Split huge pages on write-notify or COW")
Signed-off-by: James Gowans <jgowans@amazon.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Higher order allocations for vmemmap pages from buddy allocator must be
able to be treated as indepdenent small pages as they can be freed
individually by the caller. There is no problem for higher order vmemmap
pages allocated at boot time since each individual small page will be
initialized at boot time. However, it will be an issue for memory hotplug
case since those higher order vmemmap pages are allocated from buddy
allocator without initializing each individual small page's refcount. The
system will panic in put_page_testzero() when CONFIG_DEBUG_VM is enabled
if the vmemmap page is freed.
Link: https://lkml.kernel.org/r/20220620023019.94257-1-songmuchun@bytedance.com
Fixes: d8d55f5616 ("mm: sparsemem: use page table lock to protect kernel pmd operations")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The huge_ptep_set_access_flags() can not make the huge pte old according
to the discussion [1], that means we will always mornitor the young state
of the hugetlb though we stopped accessing the hugetlb, as a result DAMON
will get inaccurate accessing statistics.
So changing to use set_huge_pte_at() to make the huge pte old to fix this
issue.
[1] https://lore.kernel.org/all/Yqy97gXI4Nqb7dYo@arm.com/
Link: https://lkml.kernel.org/r/1655692482-28797-1-git-send-email-baolin.wang@linux.alibaba.com
Fixes: 49f4203aae ("mm/damon: add access checking for hugetlb pages")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When fallocate() is used on a shmem file, the pages we allocate can end up
with !PageUptodate.
Since UFFDIO_CONTINUE tries to find the existing page the user wants to
map with SGP_READ, we would fail to find such a page, since
shmem_getpage_gfp returns with a "NULL" pagep for SGP_READ if it discovers
!PageUptodate. As a result, UFFDIO_CONTINUE returns -EFAULT, as it would
do if the page wasn't found in the page cache at all.
This isn't the intended behavior. UFFDIO_CONTINUE is just trying to find
if a page exists, and doesn't care whether it still needs to be cleared or
not. So, instead of SGP_READ, pass in SGP_NOALLOC. This is the same,
except for one critical difference: in the !PageUptodate case, SGP_NOALLOC
will clear the page and then return it. With this change, UFFDIO_CONTINUE
works properly (succeeds) on a shmem file which has been fallocated, but
otherwise not modified.
Link: https://lkml.kernel.org/r/20220610173812.1768919-1-axelrasmussen@google.com
Fixes: 153132571f ("userfaultfd/shmem: support UFFDIO_CONTINUE for shmem")
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A recent commit factored out a series of annoying (unsigned long) casts
into a single variable declaration, but made the pointer type a
`uintptr_t` rather than the usual `unsigned long`. This patch changes it
to be the integer type more typically used by the kernel to represent
addresses.
Fixes: 35fb9ae4aa ("usercopy: Cast pointer to an integer once")
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220616143617.449094-1-Jason@zx2c4.com
The worst case is that the new memory range overlaps all existing
regions, which requires type->cnt + 1 empty struct memblock_region slots in
the type->regions array.
So if type->cnt + 1 + type->cnt is less than type->max, we can insert
regions directly rather than calculate the needed amount before the
insertion.
And becase of merge operation in the end of function, tpye->cnt will
increase slowly for many cases.
This change allows to avoid unnecessary repeat of memblock ranges traversal
for many cases when adding new memory range.
Signed-off-by: Jinyu Tang <tjytimi@163.com>
[rppt: massaged comment and changelog text]
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
By passing ->read_folio to filemap_read_folio(), we can use
filemap_read_folio() in do_read_cache_folio().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
If the call to filler() returns AOP_TRUNCATED_PAGE, we need to
retry the page cache lookup.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
No functionality change intended; this simply moves code around to
disentangle the function a little.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
All callers of find_get_pages_range(), pagevec_lookup_range() and
pagevec_lookup() have now been removed.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
This is a straightforward conversion.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Change the guts of check_move_unevictable_pages() over to use folios
and add check_move_unevictable_pages() as a wrapper.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
This is the equivalent of find_get_pages() but fills a folio_batch
instead of an array of pages.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
These functions have no more users, so delete them.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Remove the last caller of add_to_page_cache()
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
If the last folio in a file is split as a result of truncation,
we simply clear the dirty bits for the pages we're discarding.
That causes NR_FILE_DIRTY (among other counters) to be thrown off
and eventually Linux will hang in balance_dirty_pages_ratelimited()
Reported-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Fixes: d68eccad37 ("mm/filemap: Allow large folios to be added to the page cache")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
All architecture-independent users of virt_to_bus() and bus_to_virt()
have been fixed to use the dma mapping interfaces or have been
removed now. This means the definitions on most architectures, and the
CONFIG_VIRT_TO_BUS symbol are now obsolete and can be removed.
The only exceptions to this are a few network and scsi drivers for m68k
Amiga and VME machines and ppc32 Macintosh. These drivers work correctly
with the old interfaces and are probably not worth changing.
On alpha and parisc, virt_to_bus() were still used in asm/floppy.h.
alpha can use isa_virt_to_bus() like x86 does, and parisc can just
open-code the virt_to_phys() here, as this is architecture specific
code.
I tried updating the bus-virt-phys-mapping.rst documentation, which
started as an email from Linus to explain some details of the Linux-2.0
driver interfaces. The bits about virt_to_bus() were declared obsolete
backin 2000, and the rest is not all that relevant any more, so in the
end I just decided to remove the file completely.
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
so it will be consistent with code mm directory and with
Documentation/admin-guide/mm and won't be confused with virtual machines.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Wu XiangCheng <bobwxc@email.cn>
Add special hook for architecture to verify addr, size or prot
when ioremap() or iounmap(), which will make the generic ioremap
more useful.
ioremap_allowed() return a bool,
- true means continue to remap
- false means skip remap and return directly
iounmap_allowed() return a bool,
- true means continue to vunmap
- false code means skip vunmap and return directly
Meanwhile, only vunmap the address when it is in vmalloc area
as the generic ioremap only returns vmalloc addresses.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220607125027.44946-5-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Show physical address of each ioremap in /proc/vmallocinfo.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Link: https://lore.kernel.org/r/20220607125027.44946-4-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Use more meaningful and sensible naming phys_addr
instead addr in ioremap_prot().
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220610092255.32445-1-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Fixes for post-5.18 changes:
- fix for a damon boot hang, from SeongJae
- fix for a kfence warning splat, from Jason Donenfeld
- fix for zero-pfn pinning, from Alex Williamson
- fix for fallocate hole punch clearing, from Mike Kravetz
Fixes pre-5.18 material:
- fix for a performance regression, from Marcelo
- fix for a hwpoisining BUG from zhenwei pi
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Merge tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull hotfixes from Andrew Morton:
"Minor things, mainly - mailmap updates, MAINTAINERS updates, etc.
Fixes for this merge window:
- fix for a damon boot hang, from SeongJae
- fix for a kfence warning splat, from Jason Donenfeld
- fix for zero-pfn pinning, from Alex Williamson
- fix for fallocate hole punch clearing, from Mike Kravetz
Fixes for previous releases:
- fix for a performance regression, from Marcelo
- fix for a hwpoisining BUG from zhenwei pi"
* tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: add entry for Christian Marangi
mm/memory-failure: disable unpoison once hw error happens
hugetlbfs: zero partial pages during fallocate hole punch
mm: memcontrol: reference to tools/cgroup/memcg_slabinfo.py
mm: re-allow pinning of zero pfns
mm/kfence: select random number before taking raw lock
MAINTAINERS: add maillist information for LoongArch
MAINTAINERS: update MM tree references
MAINTAINERS: update Abel Vesa's email
MAINTAINERS: add MEMORY HOT(UN)PLUG section and add David as reviewer
MAINTAINERS: add Miaohe Lin as a memory-failure reviewer
mailmap: add alias for jarkko@profian.com
mm/damon/reclaim: schedule 'damon_reclaim_timer' only after 'system_wq' is initialized
kthread: make it clear that kthread_create_on_node() might be terminated by any fatal signal
mm: lru_cache_disable: use synchronize_rcu_expedited
mm/page_isolation.c: fix one kernel-doc comment
Commit 793917d997 ("mm/readahead: Add large folio readahead")
introduced support for using large folios for filebacked pages if the
filesystem supports it.
page_cache_ra_order() was introduced to allocate and add these large
folios to the page cache. However adding pages to the page cache should
be serialized against truncation and hole punching by taking
invalidate_lock. Not doing so can lead to data races resulting in stale
data getting added to the page cache and marked up-to-date. See commit
730633f0b7 ("mm: Protect operations adding pages to page cache with
invalidate_lock") for more details.
This issue was found by inspection but a testcase revealed it was
possible to observe in practice on XFS. Fix this by taking
invalidate_lock in page_cache_ra_order(), to mirror what is done for the
non-thp case in page_cache_ra_unbounded().
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Fixes: 793917d997 ("mm/readahead: Add large folio readahead")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
In our efforts to remove uses of PG_private, we have found folios with
the private flag clear and folio->private not-NULL. That is the root
cause behind 642d51fb07 ("ceph: check folio PG_private bit instead
of folio->private"). It can also affect a few other filesystems that
haven't yet reported a problem.
compaction_alloc() can return a page with uninitialised page->private,
and rather than checking all the callers of migrate_pages(), just zero
page->private after calling get_new_page(). Similarly, the tail pages
from split_huge_page() may also have an uninitialised page->private.
Reported-by: Xiubo Li <xiubli@redhat.com>
Tested-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
If a read races with an invalidation followed by another read, it is
possible for a folio to be replaced with a higher-order folio. If that
happens, we'll see a sibling entry for the new folio in the next iteration
of the loop. This manifests as a NULL pointer dereference while holding
the RCU read lock.
Handle this by simply returning. The next call will find the new folio
and handle it correctly. The other ways of handling this rare race are
more complex and it's just not worth it.
Reported-by: Dave Chinner <david@fromorbit.com>
Reported-by: Brian Foster <bfoster@redhat.com>
Debugged-by: Brian Foster <bfoster@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Fixes: cbd59c48ae ("mm/filemap: use head pages in generic_file_buffered_read")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
We had an off-by-one error which meant that we never marked the first page
in a read as accessed. This was visible as a slowdown when re-reading
a file as pages were being evicted from cache too soon. In reviewing
this code, we noticed a second bug where a multi-page folio would be
marked as accessed multiple times when doing reads that were less than
the size of the folio.
Abstract the comparison of whether two file positions are in the same
folio into a new function, fixing both of these bugs.
Reported-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
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Merge tag 'slab-for-5.19-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- A slub fix for PREEMPT_RT locking semantics from Sebastian.
- A slub fix for state corruption due to a possible race scenario from
Jann.
* tag 'slab-for-5.19-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slub: add missing TID updates on slab deactivation
mm/slub: Move the stackdepot related allocation out of IRQ-off section.
Pull writeback and ext2 fixes from Jan Kara:
"A fix for writeback bug which prevented machines with kdevtmpfs from
booting and also one small ext2 bugfix in IO error handling"
* tag 'fs_for_v5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
init: Initialize noop_backing_dev_info early
ext2: fix fs corruption when trying to remove a non-empty directory with IO error
The first RCU-based object iteration loop has to modify the object count.
So we cannot skip taking the object lock.
One way to avoid soft lockup is to insert occasional cond_resched() call
into the loop. This cannot be done while holding the RCU read lock which
is to protect objects from being freed. However, taking a reference to
the object will prevent it from being freed. We can then do a
cond_resched() call after every 64k objects safely.
Link: https://lkml.kernel.org/r/20220614220359.59282-4-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are 3 RCU-based object iteration loops in kmemleak_scan(). Because
of the need to take RCU read lock, we can't insert cond_resched() into the
loop like other parts of the function. As there can be millions of
objects to be scanned, it takes a while to iterate all of them. The
kmemleak functionality is usually enabled in a debug kernel which is much
slower than a non-debug kernel. With sufficient number of kmemleak
objects, the time to iterate them all may exceed 22s causing soft lockup.
watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [kmemleak:625]
In this particular bug report, the soft lockup happen in the 2nd iteration
loop.
In the 2nd and 3rd loops, most of the objects are checked and then skipped
under the object lock. Only a selected fews are modified. Those objects
certainly need lock protection. However, the lock/unlock operation is
slow especially with interrupt disabling and enabling included.
We can actually do some basic check like color_white() without taking the
lock and skip the object accordingly. Of course, this kind of check is
racy and may miss objects that are being modified concurrently. The cost
of missed objects, however, is just that they will be discovered in the
next scan instead. The advantage of doing so is that iteration can be
done much faster especially with LOCKDEP enabled in a debug kernel.
With a debug kernel running on a 2-socket 96-thread x86-64 system
(HZ=1000), the 2nd and 3rd iteration loops speedup with this patch on the
first kmemleak_scan() call after bootup is shown in the table below.
Before patch After patch
Loop # # of objects Elapsed time # of objects Elapsed time
------ ------------ ------------ ------------ ------------
2 2,599,850 2.392s 2,596,364 0.266s
3 2,600,176 2.171s 2,597,061 0.260s
This patch reduces loop iteration times by about 88%. This will greatly
reduce the chance of a soft lockup happening in the 2nd or 3rd iteration
loops.
Even though the first loop runs a little bit faster, it can still be
problematic if many kmemleak objects are there. As the object count has
to be modified in every object, we cannot avoid taking the object lock.
So other way to prevent soft lockup will be needed.
Link: https://lkml.kernel.org/r/20220614220359.59282-3-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/kmemleak: Avoid soft lockup in kmemleak_scan()", v2.
There are 3 RCU-based object iteration loops in kmemleak_scan(). Because
of the need to take RCU read lock, we can't insert cond_resched() into the
loop like other parts of the function. As there can be millions of
objects to be scanned, it takes a while to iterate all of them. The
kmemleak functionality is usually enabled in a debug kernel which is much
slower than a non-debug kernel. With sufficient number of kmemleak
objects, the time to iterate them all may exceed 22s causing soft lockup.
watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [kmemleak:625]
This patch series make changes to the 3 object iteration loops in
kmemleak_scan() to prevent them from causing soft lockup.
This patch (of 3):
kmemleak_scan() is called only from the kmemleak scan thread or from write
to the kmemleak debugfs file. Both are in task context and so we can
directly use the simpler _irq() lock/unlock calls instead of the more
complex _irqsave/_irqrestore variants.
Similarly, kmemleak_clear() is called only from write to the kmemleak
debugfs file. The same change can be applied.
Link: https://lkml.kernel.org/r/20220614220359.59282-1-longman@redhat.com
Link: https://lkml.kernel.org/r/20220614220359.59282-2-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove unnecessary initialization for the variable 'next'. This fixes
the clang scan warning: Value stored to 'next' during its
initialization is never read [deadcode.DeadStores]
Link: https://lkml.kernel.org/r/20220612182320.160651-1-gautammenghani201@gmail.com
Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently mem_cgroup_from_obj() is not working properly with objects
allocated using vmalloc(). It creates problems in some cases, when it's
called for static objects belonging to modules or generally allocated
using vmalloc().
This patch makes mem_cgroup_from_obj() safe to be called on objects
allocated using vmalloc().
It also introduces mem_cgroup_from_slab_obj(), which is a faster version
to use in places when we know the object is either a slab object or a
generic slab page (e.g. when adding an object to a lru list).
Link: https://lkml.kernel.org/r/20220610180310.1725111-1-roman.gushchin@linux.dev
Suggested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Acked-by: Shakeel Butt <shakeelb@google.com>
Tested-by: Vasily Averin <vvs@openvz.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Qian Cai <quic_qiancai@quicinc.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Think about the below scene:
CPU1 CPU2
memunmap_pages
percpu_ref_exit
__percpu_ref_exit
free_percpu(percpu_count);
/* percpu_count is freed here! */
get_dev_pagemap
xa_load(&pgmap_array, PHYS_PFN(phys))
/* pgmap still in the pgmap_array */
percpu_ref_tryget_live(&pgmap->ref)
if __ref_is_percpu
/* __PERCPU_REF_ATOMIC_DEAD not set yet */
this_cpu_inc(*percpu_count)
/* access freed percpu_count here! */
ref->percpu_count_ptr = __PERCPU_REF_ATOMIC_DEAD;
/* too late... */
pageunmap_range
To fix the issue, do percpu_ref_exit() after pgmap_array is emptied. So
we won't do percpu_ref_tryget_live() against a being freed percpu_ref.
Link: https://lkml.kernel.org/r/20220609121305.2508-1-linmiaohe@huawei.com
Fixes: b7b3c01b19 ("mm/memremap_pages: support multiple ranges per invocation")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Check the physical address of objects for its boundary when scan instead
of in kmemleak_*_phys().
Link: https://lkml.kernel.org/r/20220611035551.1823303-5-patrick.wang.shcn@gmail.com
Fixes: 23c2d497de ("mm: kmemleak: take a full lowmem check in kmemleak_*_phys()")
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add object_phys_tree_root to store the objects allocated with physical
address. Distinguish it from object_tree_root by OBJECT_PHYS flag or
function argument. The physical address is stored directly in those
objects.
Link: https://lkml.kernel.org/r/20220611035551.1823303-4-patrick.wang.shcn@gmail.com
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add OBJECT_PHYS flag for object. This flag is used to identify the
objects allocated with physical address. The create_object_phys()
function is added as well to set that flag and is used by
kmemleak_alloc_phys().
Link: https://lkml.kernel.org/r/20220611035551.1823303-3-patrick.wang.shcn@gmail.com
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix the wrong function name dev_memremap_pages above memremap_pages() to
avoid confusion. Minor readability improvement.
Link: https://lkml.kernel.org/r/20220607143621.58989-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mempool are generally used for GFP_NOIO, so this wont benefit all that
much because might_alloc currently only checks GFP_NOFS. But it does
validate against mmu notifier pte zapping, some might catch some drivers
doing really silly things, plus it's a bit more meaningful in what we're
checking for here.
Link: https://lkml.kernel.org/r/20220605152539.3196045-3-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It only does a might_sleep_if(GFP_RECLAIM) check, which is already covered
by the might_alloc() in slab_pre_alloc_hook(). And all callers of
cache_alloc_debugcheck_before() call that beforehand already.
Link: https://lkml.kernel.org/r/20220605152539.3196045-2-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
... instead of open coding it. Completely equivalent code, just a notch
more meaningful when reading.
Link: https://lkml.kernel.org/r/20220605152539.3196045-1-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are already statistics of {pgscan,pgsteal}_kswapd and
{pgscan,pgsteal}_direct of memcg event here, but now only the sum of the
two is displayed in memory.stat of cgroup v2.
In order to obtain more accurate information during monitoring and
debugging, and to align with the display in /proc/vmstat, it better to
display {pgscan,pgsteal}_kswapd and {pgscan,pgsteal}_direct separately.
Also, for forward compatibility, we still display pgscan and pgsteal items
so that it won't break existing applications.
[zhengqi.arch@bytedance.com: add comment for memcg_vm_event_stat (suggested by Michal)]
Link: https://lkml.kernel.org/r/20220606154028.55030-1-zhengqi.arch@bytedance.com
[zhengqi.arch@bytedance.com: fix the doc, thanks to Johannes]
Link: https://lkml.kernel.org/r/20220607064803.79363-1-zhengqi.arch@bytedance.com
Link: https://lkml.kernel.org/r/20220604082209.55174-1-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Its behaviour is like find_vma() which finds an area above the specified
address, add comment to make it easier to understand.
And also fix two places of grammer mistake/typo.
Link: https://lkml.kernel.org/r/20220607105958.382076-5-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In __purge_vmap_area_lazy(), rename local_pure_list to local_purge_list.
Link: https://lkml.kernel.org/r/20220607105958.382076-4-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In find_va_links(), when traversing the vmap_area tree, the comparing to
check if the passed in 'va' is above or below 'tmp_va' is redundant,
assuming both 'va' and 'tmp_va' has ->va_start <= ->va_end.
Here, to simplify the checking as code change.
Link: https://lkml.kernel.org/r/20220607105958.382076-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Cleanup patches of vmalloc", v2.
Some cleanup patches found when reading vmalloc code.
This patch (of 4):
adjust_va_to_fit_type() checks all values of passed in fit type, including
NOTHING_FIT in the else branch. However, the check of NOTHING_FIT has
been done inside adjust_va_to_fit_type() and before it's called in all
call sites.
In fact, both of these functions are coupled tightly, since
classify_va_fit_type() is doing the preparation work for
adjust_va_to_fit_type(). So putting invocation of classify_va_fit_type()
inside adjust_va_to_fit_type() can simplify code logic and the redundant
check of NOTHING_FIT issue will go away.
Link: https://lkml.kernel.org/r/20220607105958.382076-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20220607105958.382076-2-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Suggested-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In check_pfn_span(), a 'reason' string is being used to recreate the
caller function name, while printing the warning message. It is really
unnecessary as the warning message could just be printed inside the caller
depending on the return code. Currently there are just two callers for
check_pfn_span() i.e __add_pages() and __remove_pages(). Let's clean this
up.
Link: https://lkml.kernel.org/r/20220531090441.170650-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
shmem_swapin_folio has changed to use folio but comment still mentions
page. Update the relevant comment accordingly as suggested by Naoya.
Link: https://lkml.kernel.org/r/20220530115841.4348-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
I observed that for each of the shared file-backed page faults, we're very
likely to retry one more time for the 1st write fault upon no page. It's
because we'll need to release the mmap lock for dirty rate limit purpose
with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()).
Then after that throttling we return VM_FAULT_RETRY.
We did that probably because VM_FAULT_RETRY is the only way we can return
to the fault handler at that time telling it we've released the mmap lock.
However that's not ideal because it's very likely the fault does not need
to be retried at all since the pgtable was well installed before the
throttling, so the next continuous fault (including taking mmap read lock,
walk the pgtable, etc.) could be in most cases unnecessary.
It's not only slowing down page faults for shared file-backed, but also add
more mmap lock contention which is in most cases not needed at all.
To observe this, one could try to write to some shmem page and look at
"pgfault" value in /proc/vmstat, then we should expect 2 counts for each
shmem write simply because we retried, and vm event "pgfault" will capture
that.
To make it more efficient, add a new VM_FAULT_COMPLETED return code just to
show that we've completed the whole fault and released the lock. It's also
a hint that we should very possibly not need another fault immediately on
this page because we've just completed it.
This patch provides a ~12% perf boost on my aarch64 test VM with a simple
program sequentially dirtying 400MB shmem file being mmap()ed and these are
the time it needs:
Before: 650.980 ms (+-1.94%)
After: 569.396 ms (+-1.38%)
I believe it could help more than that.
We need some special care on GUP and the s390 pgfault handler (for gmap
code before returning from pgfault), the rest changes in the page fault
handlers should be relatively straightforward.
Another thing to mention is that mm_account_fault() does take this new
fault as a generic fault to be accounted, unlike VM_FAULT_RETRY.
I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do
not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping
them as-is.
Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vineet Gupta <vgupta@kernel.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm part]
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Stafford Horne <shorne@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Will Deacon <will@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Helge Deller <deller@gmx.de>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
<linux/mm.h> already provides the PAGE_ALIGNED macro. Let's use this
macro instead of IS_ALIGNED and passing PAGE_SIZE directly.
Link: https://lkml.kernel.org/r/20220526140257.1568744-1-bh1scw@gmail.com
Signed-off-by: Fanjun Kong <bh1scw@gmail.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There is no slabinfo.py in tools/cgroup, but has memcg_slabinfo.py instead.
Link: https://lkml.kernel.org/r/20220610024451.744135-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The RNG uses vanilla spinlocks, not raw spinlocks, so kfence should pick
its random numbers before taking its raw spinlocks. This also has the
nice effect of doing less work inside the lock. It should fix a splat
that Geert saw with CONFIG_PROVE_RAW_LOCK_NESTING:
dump_backtrace.part.0+0x98/0xc0
show_stack+0x14/0x28
dump_stack_lvl+0xac/0xec
dump_stack+0x14/0x2c
__lock_acquire+0x388/0x10a0
lock_acquire+0x190/0x2c0
_raw_spin_lock_irqsave+0x6c/0x94
crng_make_state+0x148/0x1e4
_get_random_bytes.part.0+0x4c/0xe8
get_random_u32+0x4c/0x140
__kfence_alloc+0x460/0x5c4
kmem_cache_alloc_trace+0x194/0x1dc
__kthread_create_on_node+0x5c/0x1a8
kthread_create_on_node+0x58/0x7c
printk_start_kthread.part.0+0x34/0xa8
printk_activate_kthreads+0x4c/0x54
do_one_initcall+0xec/0x278
kernel_init_freeable+0x11c/0x214
kernel_init+0x24/0x124
ret_from_fork+0x10/0x20
Link: https://lkml.kernel.org/r/20220609123319.17576-1-Jason@zx2c4.com
Fixes: d4150779e6 ("random32: use real rng for non-deterministic randomness")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
