dax_pmd_insert_mapping() contains the following code:
pfn_t pfn;
if (bdev_dax_pgoff(bdev, sector, size, &pgoff) != 0)
goto fallback;
/* ... */
fallback:
trace_dax_pmd_insert_mapping_fallback(inode, vmf, length, pfn, ret);
When the condition in the if statement fails, the function calls
trace_dax_pmd_insert_mapping_fallback() with an uninitialized pfn value.
This issue has been found while building the kernel with clang. The
compiler reported:
fs/dax.c:1280:6: error: variable 'pfn' is used uninitialized
whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
if (bdev_dax_pgoff(bdev, sector, size, &pgoff) != 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/dax.c:1310:60: note: uninitialized use occurs here
trace_dax_pmd_insert_mapping_fallback(inode, vmf, length, pfn, ret);
^~~
Link: http://lkml.kernel.org/r/20170903083000.587-1-nicolas.iooss_linux@m4x.org
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree.
This has three major drawbacks:
1) It consumes memory unnecessarily. For every 4k page that is read via
a DAX mmap() over a hole, we allocate a new page cache page. This
means that if you read 1GiB worth of pages, you end up using 1GiB of
zeroed memory. This is easily visible by looking at the overall
memory consumption of the system or by looking at /proc/[pid]/smaps:
7f62e72b3000-7f63272b3000 rw-s 00000000 103:00 12 /root/dax/data
Size: 1048576 kB
Rss: 1048576 kB
Pss: 1048576 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 1048576 kB
Private_Dirty: 0 kB
Referenced: 1048576 kB
Anonymous: 0 kB
LazyFree: 0 kB
AnonHugePages: 0 kB
ShmemPmdMapped: 0 kB
Shared_Hugetlb: 0 kB
Private_Hugetlb: 0 kB
Swap: 0 kB
SwapPss: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
2) It is slower than using a common zero page because each page fault
has more work to do. Instead of just inserting a common zero page we
have to allocate a page cache page, zero it, and then insert it. Here
are the average latencies of dax_load_hole() as measured by ftrace on
a random test box:
Old method, using zeroed page cache pages: 3.4 us
New method, using the common 4k zero page: 0.8 us
This was the average latency over 1 GiB of sequential reads done by
this simple fio script:
[global]
size=1G
filename=/root/dax/data
fallocate=none
[io]
rw=read
ioengine=mmap
3) The fact that we had to check for both DAX exceptional entries and
for page cache pages in the radix tree made the DAX code more
complex.
Solve these issues by following the lead of the DAX PMD code and using a
common 4k zero page instead. As with the PMD code we will now insert a
DAX exceptional entry into the radix tree instead of a struct page
pointer which allows us to remove all the special casing in the DAX
code.
Note that we do still pretty aggressively check for regular pages in the
DAX radix tree, especially where we take action based on the bits set in
the page. If we ever find a regular page in our radix tree now that
most likely means that someone besides DAX is inserting pages (which has
happened lots of times in the past), and we want to find that out early
and fail loudly.
This solution also removes the extra memory consumption. Here is that
same /proc/[pid]/smaps after 1GiB of reading from a hole with the new
code:
7f2054a74000-7f2094a74000 rw-s 00000000 103:00 12 /root/dax/data
Size: 1048576 kB
Rss: 0 kB
Pss: 0 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 0 kB
Anonymous: 0 kB
LazyFree: 0 kB
AnonHugePages: 0 kB
ShmemPmdMapped: 0 kB
Shared_Hugetlb: 0 kB
Private_Hugetlb: 0 kB
Swap: 0 kB
SwapPss: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
Overall system memory consumption is similarly improved.
Another major change is that we remove dax_pfn_mkwrite() from our fault
flow, and instead rely on the page fault itself to make the PTE dirty
and writeable. The following description from the patch adding the
vm_insert_mixed_mkwrite() call explains this a little more:
"To be able to use the common 4k zero page in DAX we need to have our
PTE fault path look more like our PMD fault path where a PTE entry
can be marked as dirty and writeable as it is first inserted rather
than waiting for a follow-up dax_pfn_mkwrite() =>
finish_mkwrite_fault() call.
Right now we can rely on having a dax_pfn_mkwrite() call because we
can distinguish between these two cases in do_wp_page():
case 1: 4k zero page => writable DAX storage
case 2: read-only DAX storage => writeable DAX storage
This distinction is made by via vm_normal_page(). vm_normal_page()
returns false for the common 4k zero page, though, just as it does
for DAX ptes. Instead of special casing the DAX + 4k zero page case
we will simplify our DAX PTE page fault sequence so that it matches
our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper.
We will instead use dax_iomap_fault() to handle write-protection
faults.
This means that insert_pfn() needs to follow the lead of
insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If
'mkwrite' is set insert_pfn() will do the work that was previously
done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path"
Link: http://lkml.kernel.org/r/20170724170616.25810-4-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree. This has three major
drawbacks:
1) It consumes memory unnecessarily. For every 4k page that is read via
a DAX mmap() over a hole, we allocate a new page cache page. This
means that if you read 1GiB worth of pages, you end up using 1GiB of
zeroed memory.
2) It is slower than using a common zero page because each page fault
has more work to do. Instead of just inserting a common zero page we
have to allocate a page cache page, zero it, and then insert it.
3) The fact that we had to check for both DAX exceptional entries and
for page cache pages in the radix tree made the DAX code more
complex.
This series solves these issues by following the lead of the DAX PMD
code and using a common 4k zero page instead. This reduces memory usage
and decreases latencies for some workloads, and it simplifies the DAX
code, removing over 100 lines in total.
This patch (of 5):
To be able to use the common 4k zero page in DAX we need to have our PTE
fault path look more like our PMD fault path where a PTE entry can be
marked as dirty and writeable as it is first inserted rather than
waiting for a follow-up dax_pfn_mkwrite() => finish_mkwrite_fault()
call.
Right now we can rely on having a dax_pfn_mkwrite() call because we can
distinguish between these two cases in do_wp_page():
case 1: 4k zero page => writable DAX storage
case 2: read-only DAX storage => writeable DAX storage
This distinction is made by via vm_normal_page(). vm_normal_page()
returns false for the common 4k zero page, though, just as it does for
DAX ptes. Instead of special casing the DAX + 4k zero page case we will
simplify our DAX PTE page fault sequence so that it matches our DAX PMD
sequence, and get rid of the dax_pfn_mkwrite() helper. We will instead
use dax_iomap_fault() to handle write-protection faults.
This means that insert_pfn() needs to follow the lead of
insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If 'mkwrite'
is set insert_pfn() will do the work that was previously done by
wp_page_reuse() as part of the dax_pfn_mkwrite() call path.
Link: http://lkml.kernel.org/r/20170724170616.25810-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking updates from David Miller:
1) Support ipv6 checksum offload in sunvnet driver, from Shannon
Nelson.
2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric
Dumazet.
3) Allow generic XDP to work on virtual devices, from John Fastabend.
4) Add bpf device maps and XDP_REDIRECT, which can be used to build
arbitrary switching frameworks using XDP. From John Fastabend.
5) Remove UFO offloads from the tree, gave us little other than bugs.
6) Remove the IPSEC flow cache, from Florian Westphal.
7) Support ipv6 route offload in mlxsw driver.
8) Support VF representors in bnxt_en, from Sathya Perla.
9) Add support for forward error correction modes to ethtool, from
Vidya Sagar Ravipati.
10) Add time filter for packet scheduler action dumping, from Jamal Hadi
Salim.
11) Extend the zerocopy sendmsg() used by virtio and tap to regular
sockets via MSG_ZEROCOPY. From Willem de Bruijn.
12) Significantly rework value tracking in the BPF verifier, from Edward
Cree.
13) Add new jump instructions to eBPF, from Daniel Borkmann.
14) Rework rtnetlink plumbing so that operations can be run without
taking the RTNL semaphore. From Florian Westphal.
15) Support XDP in tap driver, from Jason Wang.
16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal.
17) Add Huawei hinic ethernet driver.
18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan
Delalande.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits)
i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
i40e: avoid NVM acquire deadlock during NVM update
drivers: net: xgene: Remove return statement from void function
drivers: net: xgene: Configure tx/rx delay for ACPI
drivers: net: xgene: Read tx/rx delay for ACPI
rocker: fix kcalloc parameter order
rds: Fix non-atomic operation on shared flag variable
net: sched: don't use GFP_KERNEL under spin lock
vhost_net: correctly check tx avail during rx busy polling
net: mdio-mux: add mdio_mux parameter to mdio_mux_init()
rxrpc: Make service connection lookup always check for retry
net: stmmac: Delete dead code for MDIO registration
gianfar: Fix Tx flow control deactivation
cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6
cxgb4: Fix pause frame count in t4_get_port_stats
cxgb4: fix memory leak
tun: rename generic_xdp to skb_xdp
tun: reserve extra headroom only when XDP is set
net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping
net: dsa: bcm_sf2: Advertise number of egress queues
...
Pull writeback error handling updates from Jeff Layton:
"This pile continues the work from last cycle on better tracking
writeback errors. In v4.13 we added some basic errseq_t infrastructure
and converted a few filesystems to use it.
This set continues refining that infrastructure, adds documentation,
and converts most of the other filesystems to use it. The main
exception at this point is the NFS client"
* tag 'wberr-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
ecryptfs: convert to file_write_and_wait in ->fsync
mm: remove optimizations based on i_size in mapping writeback waits
fs: convert a pile of fsync routines to errseq_t based reporting
gfs2: convert to errseq_t based writeback error reporting for fsync
fs: convert sync_file_range to use errseq_t based error-tracking
mm: add file_fdatawait_range and file_write_and_wait
fuse: convert to errseq_t based error tracking for fsync
mm: consolidate dax / non-dax checks for writeback
Documentation: add some docs for errseq_t
errseq: rename __errseq_set to errseq_set
Pull file locking updates from Jeff Layton:
"This pile just has a few file locking fixes from Ben Coddington. There
are a couple of cleanup patches + an attempt to bring sanity to the
l_pid value that is reported back to userland on an F_GETLK request.
After a few gyrations, he came up with a way for filesystems to
communicate to the VFS layer code whether the pid should be translated
according to the namespace or presented as-is to userland"
* tag 'locks-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
locks: restore a warn for leaked locks on close
fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks
fs/locks: Use allocation rather than the stack in fcntl_getlk()
Pull dlm updates from David Teigland:
"This set includes a bunch of minor code cleanups that have
accumulated, probably from code analyzers people like to run. There is
one nice fix that avoids some socket leaks by switching to use
sock_create_lite()"
* tag 'dlm-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: use sock_create_lite inside tcp_accept_from_sock
uapi linux/dlm_netlink.h: include linux/dlmconstants.h
dlm: avoid double-free on error path in dlm_device_{register,unregister}
dlm: constify kset_uevent_ops structure
dlm: print log message when cluster name is not set
dlm: Delete an unnecessary variable initialisation in dlm_ls_start()
dlm: Improve a size determination in two functions
dlm: Use kcalloc() in two functions
dlm: Use kmalloc_array() in make_member_array()
dlm: Delete an error message for a failed memory allocation in dlm_recover_waiters_pre()
dlm: Improve a size determination in dlm_recover_waiters_pre()
dlm: Use kcalloc() in dlm_scan_waiters()
dlm: Improve a size determination in table_seq_start()
dlm: Add spaces for better code readability
dlm: Replace six seq_puts() calls by seq_putc()
dlm: Make dismatch error message more clear
dlm: Fix kernel memory disclosure
Pull ext4 updates from Ted Ts'o:
"Scalability improvements when allocating inodes, and some
miscellaneous bug fixes and cleanups"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: avoid Y2038 overflow in recently_deleted()
ext4: fix fault handling when mounted with -o dax,ro
ext4: fix quota inconsistency during orphan cleanup for read-only mounts
ext4: fix incorrect quotaoff if the quota feature is enabled
ext4: remove useless test and assignment in strtohash functions
ext4: backward compatibility support for Lustre ea_inode implementation
ext4: remove timebomb in ext4_decode_extra_time()
ext4: use sizeof(*ptr)
ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets
ext4: reduce lock contention in __ext4_new_inode
ext4: cleanup goto next group
ext4: do not unnecessarily allocate buffer in recently_deleted()
Pull XFS updates from Darrick Wong:
"Here are the changes for xfs for 4.14. Most of these are cleanups and
fixes for bad behavior, as we're mostly focusing on improving
reliablity this cycle (read: there's potentially a lot of stuff on the
horizon for 4.15 so better to spend a few weeks killing other bugs
now).
Summary:
- Write unmount record for a ro mount to avoid unnecessary log replay
- Clean up orphaned inodes when mounting fs readonly
- Resubmit inode log items when buffer writeback fails to avoid
umount hang
- Fix log recovery corruption problems when log headers wrap around
the end
- Avoid infinite loop searching for free inodes when inode counters
are wrong
- Evict inodes involved with log redo so that we don't leak them
later
- Fix a potential race between reclaim and inode cluster freeing
- Refactor the inode joining code w.r.t. transaction rolling &
deferred ops
- Fix a bug where the log doesn't properly deal with dirty buffers
that are about to become ordered buffers
- Fix the extent swap code to deal with making dirty buffers ordered
properly
- Consolidate page fault handlers
- Refactor the incore extent manipulation functions to use the iext
abstractions instead of directly modifying with extent data
- Disable crashy chattr +/-x until we fix it
- Don't allow us to set S_DAX for v2 inodes
- Various cleanups
- Clarify some documentation
- Fix a problem where fsync and a log commit race to send the disk a
flush command, resulting in a small window where power fail data
loss could occur
- Simplify some rmap operations in the fcollapse code
- Fix some use-after-free problems in async writeback"
* tag 'xfs-4.14-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (44 commits)
xfs: use kmem_free to free return value of kmem_zalloc
xfs: open code end_buffer_async_write in xfs_finish_page_writeback
xfs: don't set v3 xflags for v2 inodes
xfs: fix compiler warnings
fsmap: fix documentation of FMR_OF_LAST
xfs: simplify the rmap code in xfs_bmse_merge
xfs: remove unused flags arg from xfs_file_iomap_begin_delay
xfs: fix incorrect log_flushed on fsync
xfs: disable per-inode DAX flag
xfs: replace xfs_qm_get_rtblks with a direct call to xfs_bmap_count_leaves
xfs: rewrite xfs_bmap_count_leaves using xfs_iext_get_extent
xfs: use xfs_iext_*_extent helpers in xfs_bmap_split_extent_at
xfs: use xfs_iext_*_extent helpers in xfs_bmap_shift_extents
xfs: move some code around inside xfs_bmap_shift_extents
xfs: use xfs_iext_get_extent in xfs_bmap_first_unused
xfs: switch xfs_bmap_local_to_extents to use xfs_iext_insert
xfs: add a xfs_iext_update_extent helper
xfs: consolidate the various page fault handlers
iomap: return VM_FAULT_* codes from iomap_page_mkwrite
xfs: relog dirty buffers during swapext bmbt owner change
...
Pull GFS2 updates from Bob Peterson:
"We've got a whopping 29 GFS2 patches for this merge window, mainly
because we held some back from the previous merge window until we
could get them perfected and well tested. We have a couple patch sets,
including my patch set for protecting glock gl_object and Andreas
Gruenbacher's patch set to fix the long-standing shrink- slab hang,
plus a bunch of assorted bugs and cleanups.
Summary:
- I fixed a bug whereby an IO error would lead to a double-brelse.
- Andreas Gruenbacher made a minor cleanup to call his relatively new
function, gfs2_holder_initialized, rather than doing it manually.
This was just missed by a previous patch set.
- Jan Kara fixed a bug whereby the SGID was being cleared when
inheriting ACLs.
- Andreas found a bug and fixed it in his previous patch, "Get rid of
flush_delayed_work in gfs2_evict_inode". A call to
flush_delayed_work was deleted from *gfs2_inode_lookup and added to
gfs2_create_inode.
- Wang Xibo found and fixed a list_add call in inode_go_lock that
specified the parameters in the wrong order.
- Coly Li submitted a patch to add the REQ_PRIO to some of GFS2's
metadata reads that were accidentally missing them.
- I submitted a 4-patch set to protect the glock gl_object field.
GFS2 was setting and checking gl_object with no locking mechanism,
so the value was occasionally stomped on, which caused file system
corruption.
- I submitted a small cleanup to function gfs2_clear_rgrpd. It was
needlessly adding rgrp glocks to the lru list, then pulling them
back off immediately. The rgrp glocks don't use the lru list
anyway, so doing so was just a waste of time.
- I submitted a patch that checks the GLOF_LRU flag on a glock before
trying to remove it from the lru_list. This avoids a lot of
unnecessary spin_lock contention.
- I submitted a patch to delete GFS2's debugfs files only after we
evict all the glocks. Before this patch, GFS2 would delete the
debugfs files, and if unmount hung waiting for a glock, there was
no way to debug the problem. Now, if a hang occurs during umount,
we can examine the debugfs files to figure out why it's hung.
- Andreas Gruenbacher submitted a patch to fix some trivial typos.
- Andreas also submitted a five-part patch set to fix the
longstanding hang involving the slab shrinker: dlm requires memory,
calls the inode shrinker, which calls gfs2's evict, which calls
back into DLM before it can evict an inode.
- Abhi Das submitted a patch to forcibly flush the active items list
to relieve memory pressure. This fixes a long-standing bug whereby
GFS2 was getting hung permanently in balance_dirty_pages.
- Thomas Tai submitted a patch to fix a slab corruption problem due
to a residual pointer left in the lock_dlm lockstruct.
- I submitted a patch to withdraw the file system if IO errors are
encountered while writing to the journals or statfs system file
which were previously not being sent back up. Before, some IO
errors were sometimes not be detected for several hours, and at
recovery time, the journal errors made journal replay impossible.
- Andreas has a patch to fix an annoying format-truncation compiler
warning so GFS2 compiles cleanly.
- I have a patch that fixes a handful of sparse compiler warnings.
- Andreas fixed up an useless gl_object warning caused by an earlier
patch.
- Arvind Yadav added a patch to properly constify our rhashtable
params declare.
- I added a patch to fix a regression caused by the non-recursive
delete and truncate patch that caused file system blocks to not be
properly freed.
- Ernesto A. Fernández added a patch to fix a place where GFS2 would
send back the wrong return code setting extended attributes.
- Ernesto also added a patch to fix a case in which GFS2 was
improperly setting an inode's i_mode, potentially granting access
to the wrong users"
* tag 'gfs2-4.14.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (29 commits)
gfs2: preserve i_mode if __gfs2_set_acl() fails
gfs2: don't return ENODATA in __gfs2_xattr_set unless replacing
GFS2: Fix non-recursive truncate bug
gfs2: constify rhashtable_params
GFS2: Fix gl_object warnings
GFS2: Fix up some sparse warnings
gfs2: Silence gcc format-truncation warning
GFS2: Withdraw for IO errors writing to the journal or statfs
gfs2: fix slab corruption during mounting and umounting gfs file system
gfs2: forcibly flush ail to relieve memory pressure
gfs2: Clean up waiting on glocks
gfs2: Defer deleting inodes under memory pressure
gfs2: gfs2_evict_inode: Put glocks asynchronously
gfs2: Get rid of gfs2_set_nlink
gfs2: gfs2_glock_get: Wait on freeing glocks
gfs2: Fix trivial typos
GFS2: Delete debugfs files only after we evict the glocks
GFS2: Don't waste time locking lru_lock for non-lru glocks
GFS2: Don't bother trying to add rgrps to the lru list
GFS2: Clear gl_object when deleting an inode in gfs2_delete_inode
...
Ville Syrjälä spotted that PGETBL_CTL was losing its enable bit upon a
reset. That was causing the display to show garbage on his 945gm. On my
i915gm the effect was far more severe; re-enabling the display following
the reset without PGETBL_CTL being enabled lead to an immediate hard
hang.
We do have a routine to re-enable PGETBL_CTL which is applicable to
gen2-4, although on gen4 it is documented that a graphics reset doesn't
alter the register (no such wording is given for gen3) and should be safe
to call to punch back in the enable bit. However, that leaves the question
of whether we need to completely re-initialise the register and the
rest of the GSM. For g33/pnv/gen4+, where we do have a configurable
page table, its contents do seem to be kept, and so we should be able to
recover without having to reinitialise the GTT from scratch (as prior to
g33, that register is configured by the BIOS and we leave alone except
for the enable bit).
This appears to have been broken by commit 5fbd0418ee ("drm/i915:
Re-enable GGTT earlier during resume on pre-gen6 platforms"), which
moved the intel_enable_gtt() from i915_gem_init_hw() (also used by
reset) to add it earlier during hw init and resume, missing the reset
path.
v2: Find the culprit, rearrange ggtt_enable to be before gem_init_hw to
match init/resume
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Fixes: 5fbd0418ee ("drm/i915: Re-enable GGTT earlier during resume on pre-gen6 platforms")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101852
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170906111405.27110-1-chris@chris-wilson.co.uk
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit 0db8c96120)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Commit 6c6b6f28b3 ("loop: set physical block size to PAGE_SIZE")
caused mkfs.xfs to barf on ppc64 [1]. Always using PAGE_SIZE as the
physical block size still makes the most sense semantically, but let's
just lie and always set it to the same value as the logical block size
(same goes for io_min). In the future we might want to at least bump up
io_min to PAGE_SIZE but I'm sick of these stupid changes so let's play
it safe.
1: https://marc.info/?l=linux-xfs&m=150459024723753&w=2
Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't populate the arrays cdb on the stack, instead make them static.
Makes the object code smaller by 230 bytes:
Before:
text data bss dec hex filename
3797 240 0 4037 fc5 drivers/ata/libata-zpodd.o
After:
text data bss dec hex filename
3407 400 0 3807 edf drivers/ata/libata-zpodd.o
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Most importantly, solve a crash where %llu was used to format signed
numbers. This would cause a buffer overflow when reading sysfs
writeback_rate_debug, as only 20 bytes were allocated for this and
%llu writes 20 characters plus a null.
Always use the units mechanism rather than having different output
paths for simplicity.
Also, correct problems with display output where 1.10 was a larger
number than 1.09, by multiplying by 10 and then dividing by 1024 instead
of dividing by 100. (Remainders of >= 1000 would print as .10).
Minor changes: Always display the decimal point instead of trying to
omit it based on number of digits shown. Decide what units to use
based on 1000 as a threshold, not 1024 (in other words, always print
at most 3 digits before the decimal point).
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reported-by: Dmitry Yu Okunev <dyokunev@ut.mephi.ru>
Acked-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In olden times, closure_return() used to have a hidden return built in.
We removed the hidden return but forgot to add a new return here. If
"c" were NULL we would oops on the next line, but fortunately "c" is
never NULL. Let's just remove the if statement.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In currently, we only alloc 6 open buckets for each cache set,
but in usually, we always attach about 10 or so backend devices for
each cache set, and the each bcache device are always accessed by
about 10 or so threads in top application layer. So 6 open buckets
are too few, It has led to that each of the same thread write data
to different buckets, which would cause low efficiency write-back,
and also cause buckets inefficient, and would be Very easy to run
out of.
I add debug message in bch_open_buckets_alloc() to print alloc bucket
info, and test with ten bcache devices with a cache set, and each
bcache device is accessed by ten threads.
From the debug message, we can see that, after the modification, One
bucket is more likely to assign to the same thread, and the data from
the same thread are more likely to write the same bucket. Usually the
same thread always write/read the same backend device, so it is good
for write-back and also promote the usage efficiency of buckets.
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If you encounter any errors in bch_cached_dev_attach it will return
a negative error code. The variable 'v' which stores the result is
unsigned, thus user space sees a very large value returned for bytes
written which can cause incorrect user space behavior. Utilize 1
signed variable to use throughout the function to preserve error return
capability.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
Acked-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
__update_write_rate() uses a Proportion-Differentiation Controller
algorithm to control writeback rate. A dirty target number is used in
this PD controller to control writeback rate. A larger target number
will make the writeback rate smaller, on the versus, a smaller target
number will make the writeback rate larger.
bcache uses the following steps to calculate the target number,
1) cache_sectors = all-buckets-of-cache-set * buckets-size
2) cache_dirty_target = cache_sectors * cached-device-writeback_percent
3) target = cache_dirty_target *
(sectors-of-cached-device/sectors-of-all-cached-devices-of-this-cache-set)
The calculation at step 1) for cache_sectors is incorrect, which does
not consider dirty blocks occupied by flash only volume.
A flash only volume can be took as a bcache device without cached
device. All data sectors allocated for it are persistent on cache device
and marked dirty, they are not touched by bcache writeback and garbage
collection code. So data blocks of flash only volume should be ignore
when calculating cache_sectors of cache set.
Current code does not subtract dirty sectors of flash only volume, which
results a larger target number from the above 3 steps. And in sequence
the cache device's writeback rate is smaller then a correct value,
writeback speed is slower on all cached devices.
This patch fixes the incorrect slower writeback rate by subtracting
dirty sectors of flash only volumes in __update_writeback_rate().
(Commit log composed by Coly Li to pass checkpatch.pl checking)
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
I try to execute the following command to trigger gc thread:
[root@localhost internal]# echo 1 > trigger_gc
But it does not work, I debug the code in gc_should_run(), It works only
if in invalidating or sectors_to_gc < 0. So set sectors_to_gc to -1 to
meet the condition when we trigger gc by manual command.
(Code comments aded by Coly Li)
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Although llist provides proper APIs, they are not used. Make them used.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Sequential write IOs were tested with bs=1M by FIO in writeback cache
mode, these IOs were expected to be bypassed, but actually they did not.
We debug the code, and find in check_should_bypass():
if (!congested &&
mode == CACHE_MODE_WRITEBACK &&
op_is_write(bio_op(bio)) &&
(bio-＞bi_opf & REQ_SYNC))
goto rescale
that means, If in writeback mode, a write IO with REQ_SYNC flag will not
be bypassed though it is a sequential large IO, It's not a correct thing
to do actually, so this patch remove these codes.
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If blkdev_get_by_path() in register_bcache() fails, we try to lookup the
block device using lookup_bdev() to detect which situation we are in to
properly report error. However we never drop the reference returned to
us from lookup_bdev(). Fix that.
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When an RX BA session is started by the driver, and it has to tell
mac80211 about it, the corresponding bit in tid_rx_manage_offl gets
set and the BA session work is scheduled. Upon testing this bit, it
will call __ieee80211_start_rx_ba_session(), thus deadlocking as it
already holds the ampdu_mlme.mtx, which that acquires again.
Fix this by adding ___ieee80211_start_rx_ba_session(), a version of
the function that requires the mutex already held.
Cc: stable@vger.kernel.org
Fixes: 699cb58c8a ("mac80211: manage RX BA session offload without SKB queue")
Reported-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Commit 7a7c0a6438 ("mac80211: fix TX aggregation start/stop callback race")
added a cancellation of the ampdu work after the loop that stopped the
Tx and Rx BA sessions. However, in some cases, e.g., during HW reconfig,
the low level driver might call mac80211 APIs to complete the stopping
of the BA sessions, which would queue the ampdu work to handle the actual
completion. This work needs to be performed as otherwise mac80211 data
structures would not be properly synced.
Fix this by checking if BA session STOP_CB bit is set after the BA session
cancellation and properly clean the session.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
[Johannes: the work isn't flushed because that could do other things we
don't want, and the locking situation isn't clear]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Honor the NL80211_RRF_NO_HT40{MINUS,PLUS} flags in
reg_process_ht_flags_channel. Not doing so leads can lead
to a firmware assert in iwlwifi for example.
Fixes: b0d7aa5959 ("cfg80211: allow wiphy specific regdomain management")
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
