- Fix recent regression causing kernels built with CONFIG_PM
unset to crash on systems that support the Performance and
Energy Bias Hint (EPB) by avoiding to compile the EPB-related
code depending on CONFIG_PM when it is unset (Rafael Wysocki).
- Clean up the transition notifier invocation code in the cpufreq
core and change some users of cpufreq transition notifiers
accordingly (Viresh Kumar).
- Change MAINTAINERS to cover the schedutil governor as part of
cpufreq (Viresh Kumar).
- Simplify cpufreq_init_policy() to avoid redundant computations
(Yue Hu).
- Add explanatory comment to the cpufreq core (Rafael Wysocki).
- Introduce a new flag, GENPD_FLAG_RPM_ALWAYS_ON, to the generic
power domains (genpd) framework along with the first user of it
(Leonard Crestez).
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Merge tag 'pm-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These fix a recent regression causing kernels built with CONFIG_PM
unset to crash on systems that support the Performance and Energy Bias
Hint (EPB), clean up the cpufreq core and some users of transition
notifiers and introduce a new power domain flag into the generic power
domains framework (genpd).
Specifics:
- Fix recent regression causing kernels built with CONFIG_PM unset to
crash on systems that support the Performance and Energy Bias Hint
(EPB) by avoiding to compile the EPB-related code depending on
CONFIG_PM when it is unset (Rafael Wysocki).
- Clean up the transition notifier invocation code in the cpufreq
core and change some users of cpufreq transition notifiers
accordingly (Viresh Kumar).
- Change MAINTAINERS to cover the schedutil governor as part of
cpufreq (Viresh Kumar).
- Simplify cpufreq_init_policy() to avoid redundant computations (Yue
Hu).
- Add explanatory comment to the cpufreq core (Rafael Wysocki).
- Introduce a new flag, GENPD_FLAG_RPM_ALWAYS_ON, to the generic
power domains (genpd) framework along with the first user of it
(Leonard Crestez)"
* tag 'pm-5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
soc: imx: gpc: Use GENPD_FLAG_RPM_ALWAYS_ON for ERR009619
PM / Domains: Add GENPD_FLAG_RPM_ALWAYS_ON flag
cpufreq: Update MAINTAINERS to include schedutil governor
cpufreq: Don't find governor for setpolicy drivers in cpufreq_init_policy()
cpufreq: Explain the kobject_put() in cpufreq_policy_alloc()
cpufreq: Call transition notifier only once for each policy
x86: intel_epb: Take CONFIG_PM into account
Pull crypto fixes from Herbert Xu:
"This fixes a number of issues in the chelsio and caam drivers"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
Revert "crypto: caam/jr - Remove extra memory barrier during job ring dequeue"
crypto: caam - fix caam_dump_sg that iterates through scatterlist
crypto: caam - fix DKP detection logic
MAINTAINERS: Maintainer for Chelsio crypto driver
crypto: chelsio - count incomplete block in IV
crypto: chelsio - Fix softlockup with heavy I/O
crypto: chelsio - Fix NULL pointer dereference
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch aims to suppress 3 missing-break-in-switch false positives
on some architectures.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix afs_release() to go through the cleanup part of the function if
FMODE_WRITE is set rather than exiting through vfs_fsync() (which skips the
cleanup). The cleanup involves discarding the refs on the key used for
file ops and the writeback key record.
Also fix afs_evict_inode() to clean up any left over wb keys attached to
the inode/vnode when it is removed.
Fixes: 5a81327616 ("afs: Do better accretion of small writes on newly created content")
Signed-off-by: David Howells <dhowells@redhat.com>
media_device_cleanup() and v4l2_m2m_unregister_media_controller() were
missing in the probe error path.
While at it, re-order calls in the remove path to unregister/cleanup
things in the reverse order they were initialized/registered.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
v4l2-compliance complains that ->bus_info is empty.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This makes the function more generic so it can easily be re-used when
adding support for the decoding functionality.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Those calls are needed to restore a clean PM state when the probe fails
or when the driver is unloaded such that future ->probe() calls can
initialize runtime PM again.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Pass -1 to video_register_device() to let the core assign the first
free id instead of trying to get id 0.
In practice it doesn't make a difference since video_register_device()
is not strict about id requests and will anyway pick the first free id
starting at the id passed in argument, and passing -1 has the same
effect as passing 0. But let's comply with the API doc and pass -1
here.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
* pm-cpufreq:
cpufreq: Update MAINTAINERS to include schedutil governor
cpufreq: Don't find governor for setpolicy drivers in cpufreq_init_policy()
cpufreq: Explain the kobject_put() in cpufreq_policy_alloc()
cpufreq: Call transition notifier only once for each policy
* pm-domains:
soc: imx: gpc: Use GENPD_FLAG_RPM_ALWAYS_ON for ERR009619
PM / Domains: Add GENPD_FLAG_RPM_ALWAYS_ON flag
* acpi-bus:
ACPI: bus: change _ADR representation to 64 bits
* acpi-doc:
Documentation: ACPI: Direct references are allowed to devices only
Documentation: ACPI: Use tabs for graph ASL indentation
* acpi-pm:
ACPI: PM: Set enable_for_wake for wakeup GPEs during suspend-to-idle
The directive specified in the documentation to add an exception
for a single file in a Makefile was inverted.
Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/522362a1b934ee39d0af0abb231f68e160ecf1a8.1557874043.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is being sent to get a fix for the gcc 9.1 build warnings, and I've
also pulled in some bug fix patches that were posted in the last two
weeks.
- Avoid the gcc 9.1 warning about overflowing a union member
- Fix the wrong callback type for a single response netlink to doit
- Bug fixes from more usage of the mlx5 devx interface
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull more rdma updates from Jason Gunthorpe:
"This is being sent to get a fix for the gcc 9.1 build warnings, and
I've also pulled in some bug fix patches that were posted in the last
two weeks.
- Avoid the gcc 9.1 warning about overflowing a union member
- Fix the wrong callback type for a single response netlink to doit
- Bug fixes from more usage of the mlx5 devx interface"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
net/mlx5: Set completion EQs as shared resources
IB/mlx5: Verify DEVX general object type correctly
RDMA/core: Change system parameters callback from dumpit to doit
RDMA: Directly cast the sockaddr union to sockaddr
Merge more updates from Andrew Morton:
- a couple of hotfixes
- almost all of the rest of MM
- lib/ updates
- binfmt_elf updates
- autofs updates
- quite a lot of misc fixes and updates
- reiserfs, fatfs
- signals
- exec
- cpumask
- rapidio
- sysctl
- pids
- eventfd
- gcov
- panic
- pps
- gdb script updates
- ipc updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (126 commits)
mm: memcontrol: fix NUMA round-robin reclaim at intermediate level
mm: memcontrol: fix recursive statistics correctness & scalabilty
mm: memcontrol: move stat/event counting functions out-of-line
mm: memcontrol: make cgroup stats and events query API explicitly local
drivers/virt/fsl_hypervisor.c: prevent integer overflow in ioctl
drivers/virt/fsl_hypervisor.c: dereferencing error pointers in ioctl
mm, memcg: rename ambiguously named memory.stat counters and functions
arch: remove <asm/sizes.h> and <asm-generic/sizes.h>
treewide: replace #include <asm/sizes.h> with #include <linux/sizes.h>
fs/block_dev.c: Remove duplicate header
fs/cachefiles/namei.c: remove duplicate header
include/linux/sched/signal.h: replace `tsk' with `task'
fs/coda/psdev.c: remove duplicate header
ipc: do cyclic id allocation for the ipc object.
ipc: conserve sequence numbers in ipcmni_extend mode
ipc: allow boot time extension of IPCMNI from 32k to 16M
ipc/mqueue: optimize msg_get()
ipc/mqueue: remove redundant wq task assignment
ipc: prevent lockup on alloc_msg and free_msg
scripts/gdb: print cached rate in lx-clk-summary
...
When a cgroup is reclaimed on behalf of a configured limit, reclaim
needs to round-robin through all NUMA nodes that hold pages of the memcg
in question. However, when assembling the mask of candidate NUMA nodes,
the code only consults the *local* cgroup LRU counters, not the
recursive counters for the entire subtree. Cgroup limits are frequently
configured against intermediate cgroups that do not have memory on their
own LRUs. In this case, the node mask will always come up empty and
reclaim falls back to scanning only the current node.
If a cgroup subtree has some memory on one node but the processes are
bound to another node afterwards, the limit reclaim will never age or
reclaim that memory anymore.
To fix this, use the recursive LRU counts for a cgroup subtree to
determine which nodes hold memory of that cgroup.
The code has been broken like this forever, so it doesn't seem to be a
problem in practice. I just noticed it while reviewing the way the LRU
counters are used in general.
Link: http://lkml.kernel.org/r/20190412151507.2769-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now, when somebody needs to know the recursive memory statistics
and events of a cgroup subtree, they need to walk the entire subtree and
sum up the counters manually.
There are two issues with this:
1. When a cgroup gets deleted, its stats are lost. The state counters
should all be 0 at that point, of course, but the events are not.
When this happens, the event counters, which are supposed to be
monotonic, can go backwards in the parent cgroups.
2. During regular operation, we always have a certain number of lazily
freed cgroups sitting around that have been deleted, have no tasks,
but have a few cache pages remaining. These groups' statistics do not
change until we eventually hit memory pressure, but somebody
watching, say, memory.stat on an ancestor has to iterate those every
time.
This patch addresses both issues by introducing recursive counters at
each level that are propagated from the write side when stats change.
Upward propagation happens when the per-cpu caches spill over into the
local atomic counter. This is the same thing we do during charge and
uncharge, except that the latter uses atomic RMWs, which are more
expensive; stat changes happen at around the same rate. In a sparse
file test (page faults and reclaim at maximum CPU speed) with 5 cgroup
nesting levels, perf shows __mod_memcg_page state at ~1%.
Link: http://lkml.kernel.org/r/20190412151507.2769-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These are getting too big to be inlined in every callsite. They were
stolen from vmstat.c, which already out-of-lines them, and they have
only been growing since. The callsites aren't that hot, either.
Move __mod_memcg_state()
__mod_lruvec_state() and
__count_memcg_events() out of line and add kerneldoc comments.
Link: http://lkml.kernel.org/r/20190412151507.2769-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: memcontrol: memory.stat cost & correctness".
The cgroup memory.stat file holds recursive statistics for the entire
subtree. The current implementation does this tree walk on-demand
whenever the file is read. This is giving us problems in production.
1. The cost of aggregating the statistics on-demand is high. A lot of
system service cgroups are mostly idle and their stats don't change
between reads, yet we always have to check them. There are also always
some lazily-dying cgroups sitting around that are pinned by a handful
of remaining page cache; the same applies to them.
In an application that periodically monitors memory.stat in our
fleet, we have seen the aggregation consume up to 5% CPU time.
2. When cgroups die and disappear from the cgroup tree, so do their
accumulated vm events. The result is that the event counters at
higher-level cgroups can go backwards and confuse some of our
automation, let alone people looking at the graphs over time.
To address both issues, this patch series changes the stat
implementation to spill counts upwards when the counters change.
The upward spilling is batched using the existing per-cpu cache. In a
sparse file stress test with 5 level cgroup nesting, the additional cost
of the flushing was negligible (a little under 1% of CPU at 100% CPU
utilization, compared to the 5% of reading memory.stat during regular
operation).
This patch (of 4):
memcg_page_state(), lruvec_page_state(), memcg_sum_events() are
currently returning the state of the local memcg or lruvec, not the
recursive state.
In practice there is a demand for both versions, although the callers
that want the recursive counts currently sum them up by hand.
Per default, cgroups are considered recursive entities and generally we
expect more users of the recursive counters, with the local counts being
special cases. To reflect that in the name, add a _local suffix to the
current implementations.
The following patch will re-incarnate these functions with recursive
semantics, but with an O(1) implementation.
[hannes@cmpxchg.org: fix bisection hole]
Link: http://lkml.kernel.org/r/20190417160347.GC23013@cmpxchg.org
Link: http://lkml.kernel.org/r/20190412151507.2769-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The "param.count" value is a u64 thatcomes from the user. The code
later in the function assumes that param.count is at least one and if
it's not then it leads to an Oops when we dereference the ZERO_SIZE_PTR.
Also the addition can have an integer overflow which would lead us to
allocate a smaller "pages" array than required. I can't immediately
tell what the possible run times implications are, but it's safest to
prevent the overflow.
Link: http://lkml.kernel.org/r/20181218082129.GE32567@kadam
Fixes: 6db7199407 ("drivers/virt: introduce Freescale hypervisor management driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Timur Tabi <timur@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strndup_user() returns error pointers on error, and then in the error
handling we pass the error pointers to kfree(). It will cause an Oops.
Link: http://lkml.kernel.org/r/20181218082003.GD32567@kadam
Fixes: 6db7199407 ("drivers/virt: introduce Freescale hypervisor management driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Timur Tabi <timur@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I spent literally an hour trying to work out why an earlier version of
my memory.events aggregation code doesn't work properly, only to find
out I was calling memcg->events instead of memcg->memory_events, which
is fairly confusing.
This naming seems in need of reworking, so make it harder to do the
wrong thing by using vmevents instead of events, which makes it more
clear that these are vm counters rather than memcg-specific counters.
There are also a few other inconsistent names in both the percpu and
aggregated structs, so these are all cleaned up to be more coherent and
easy to understand.
This commit contains code cleanup only: there are no logic changes.
[akpm@linux-foundation.org: fix it for preceding changes]
Link: http://lkml.kernel.org/r/20190208224319.GA23801@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that all instances of #include <asm/sizes.h> have been replaced with
#include <linux/sizes.h>, we can remove these.
Link: http://lkml.kernel.org/r/1553267665-27228-2-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit dccd2304cc ("ARM: 7430/1: sizes.h: move from asm-generic
to <linux/sizes.h>"), <asm/sizes.h> and <asm-generic/sizes.h> are just
wrappers of <linux/sizes.h>.
This commit replaces all <asm/sizes.h> and <asm-generic/sizes.h> to
prepare for the removal.
Link: http://lkml.kernel.org/r/1553267665-27228-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/dax.h is included more than once.
Link: http://lkml.kernel.org/r/5c867e95.1c69fb81.4f15a.e5e4@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/xattr.h is included more than once.
Link: http://lkml.kernel.org/r/5c86803d.1c69fb81.1a7c6.2b78@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file uses "task" 85 times and "tsk" 25 times. It is better to be
consistent.
Link: http://lkml.kernel.org/r/20181129180547.15976-1-avagin@gmail.com
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/poll.h is included more than once.
Link: http://lkml.kernel.org/r/5c86820f.1c69fb81.149f0.0834@mx.google.com
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For ipcmni_extend mode, the sequence number space is only 7 bits. So
the chance of id reuse is relatively high compared with the non-extended
mode.
To alleviate this id reuse problem, this patch enables cyclic allocation
for the index to the radix tree (idx). The disadvantage is that this
can cause a slight slow-down of the fast path, as the radix tree could
be higher than necessary.
To limit the radix tree height, I have chosen the following limits:
1) The cycling is done over in_use*1.5.
2) At least, the cycling is done over
"normal" ipcnmi mode: RADIX_TREE_MAP_SIZE elements
"ipcmni_extended": 4096 elements
Result:
- for normal mode:
No change for <= 42 active ipc elements. With more than 42
active ipc elements, a 2nd level would be added to the radix
tree.
Without cyclic allocation, a 2nd level would be added only with
more than 63 active elements.
- for extended mode:
Cycling creates always at least a 2-level radix tree.
With more than 2730 active objects, a 3rd level would be
added, instead of > 4095 active objects until the 3rd level
is added without cyclic allocation.
For a 2-level radix tree compared to a 1-level radix tree, I have
observed < 1% performance impact.
Notes:
1) Normal "x=semget();y=semget();" is unaffected: Then the idx
is e.g. a and a+1, regardless if idr_alloc() or idr_alloc_cyclic()
is used.
2) The -1% happens in a microbenchmark after this situation:
x=semget();
for(i=0;i<4000;i++) {t=semget();semctl(t,0,IPC_RMID);}
y=semget();
Now perform semget calls on x and y that do not sleep.
3) The worst-case reuse cycle time is unfortunately unaffected:
If you have 2^24-1 ipc objects allocated, and get/remove the last
possible element in a loop, then the id is reused after 128
get/remove pairs.
Performance check:
A microbenchmark that performes no-op semop() randomly on two IDs,
with only these two IDs allocated.
The IDs were set using /proc/sys/kernel/sem_next_id.
The test was run 5 times, averages are shown.
1 & 2: Base (6.22 seconds for 10.000.000 semops)
1 & 40: -0.2%
1 & 3348: - 0.8%
1 & 27348: - 1.6%
1 & 15777204: - 3.2%
Or: ~12.6 cpu cycles per additional radix tree level.
The cpu is an Intel I3-5010U. ~1300 cpu cycles/syscall is slower
than what I remember (spectre impact?).
V2 of the patch:
- use "min" and "max"
- use RADIX_TREE_MAP_SIZE * RADIX_TREE_MAP_SIZE instead of
(2<<12).
[akpm@linux-foundation.org: fix max() warning]
Link: http://lkml.kernel.org/r/20190329204930.21620-3-longman@redhat.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Waiman Long <longman@redhat.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rewrite, based on the patch from Waiman Long:
The mixing in of a sequence number into the IPC IDs is probably to avoid
ID reuse in userspace as much as possible. With ipcmni_extend mode, the
number of usable sequence numbers is greatly reduced leading to higher
chance of ID reuse.
To address this issue, we need to conserve the sequence number space as
much as possible. Right now, the sequence number is incremented for
every new ID created. In reality, we only need to increment the
sequence number when new allocated ID is not greater than the last one
allocated. It is in such case that the new ID may collide with an
existing one. This is being done irrespective of the ipcmni mode.
In order to avoid any races, the index is first allocated and then the
pointer is replaced.
Changes compared to the initial patch:
- Handle failures from idr_alloc().
- Avoid that concurrent operations can see the wrong sequence number.
(This is achieved by using idr_replace()).
- IPCMNI_SEQ_SHIFT is not a constant, thus renamed to
ipcmni_seq_shift().
- IPCMNI_SEQ_MAX is not a constant, thus renamed to ipcmni_seq_max().
Link: http://lkml.kernel.org/r/20190329204930.21620-2-longman@redhat.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The maximum number of unique System V IPC identifiers was limited to
32k. That limit should be big enough for most use cases.
However, there are some users out there requesting for more, especially
those that are migrating from Solaris which uses 24 bits for unique
identifiers. To satisfy the need of those users, a new boot time kernel
option "ipcmni_extend" is added to extend the IPCMNI value to 16M. This
is a 512X increase which should be big enough for users out there that
need a large number of unique IPC identifier.
The use of this new option will change the pattern of the IPC
identifiers returned by functions like shmget(2). An application that
depends on such pattern may not work properly. So it should only be
used if the users really need more than 32k of unique IPC numbers.
This new option does have the side effect of reducing the maximum number
of unique sequence numbers from 64k down to 128. So it is a trade-off.
The computation of a new IPC id is not done in the performance critical
path. So a little bit of additional overhead shouldn't have any real
performance impact.
Link: http://lkml.kernel.org/r/20190329204930.21620-1-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Our msg priorities became an rbtree as of d6629859b3 ("ipc/mqueue:
improve performance of send/recv"). However, consuming a msg in
msg_get() remains logarithmic (still being better than the case before
of course). By applying well known techniques to cache pointers we can
have the node with the highest priority in O(1), which is specially nice
for the rt cases. Furthermore, some callers can call msg_get() in a
loop.
A new msg_tree_erase() helper is also added to encapsulate the tree
removal and node_cache game. Passes ltp mq testcases.
Link: http://lkml.kernel.org/r/20190321190216.1719-2-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We already store the current task fo the new waiter before calling
wq_sleep() in both send and recv paths. Trivially remove the redundant
assignment.
Link: http://lkml.kernel.org/r/20190321190216.1719-1-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The clk rate is always stored in clk_core but might be out of date and
require calls to update from hardware.
Deal with that case by printing a (c) suffix.
Link: http://lkml.kernel.org/r/1a474318982a5f0125f2360c4161029b17f56bd1.1556881728.git.leonard.crestez@nxp.com
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
An incorrect argument to list_for_each is an internal error in gdb
scripts so a TypeError should be raised. The gdb.GdbError exception
type is intended for user errors such as incorrect invocation.
Drop the type assertion in list_for_each_entry because list_for_each
isn't going to suddenly yield something else.
Applies to both list and hlist
Link: http://lkml.kernel.org/r/c1d3fd4db13d999a3ba57f5bbc1924862d824f61.1556881728.git.leonard.crestez@nxp.com
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Finding an individual clk_core requires walking the tree which can be
quite complicated so add a helper for easy access.
(gdb) print *(struct clk_scu*)$lx_clk_core_lookup("uart0_clk")->hw
Link: http://lkml.kernel.org/r/Message-ID:
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an lx-clk-summary command which prints a subset of
/sys/kernel/debug/clk/clk_summary.
This can be used to examine hangs caused by clk not being enabled.
Link: http://lkml.kernel.org/r/Message-ID:
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These scripts have some pep8 style warnings. Fix them up so that this
directory is all pep8 clean.
Link: http://lkml.kernel.org/r/20190329220844.38234-6-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement a command to print the timer list, much like how
/proc/timer_list is implemented. This can be used to look at the
pending timers on a crashed system.
[swboyd@chromium.org: v2]
Link: http://lkml.kernel.org/r/20190329220844.38234-5-swboyd@chromium.org
Link: http://lkml.kernel.org/r/20190325184522.260535-5-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement gdb functions for rb_first(), rb_last(), rb_next(), and
rb_prev(). These can be useful to iterate through the kernel's
red-black trees.
[swboyd@chromium.org: v2]
Link: http://lkml.kernel.org/r/20190329220844.38234-4-swboyd@chromium.org
Link: http://lkml.kernel.org/r/20190325184522.260535-4-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lx-configdump <file> dumps the contents of the gzipped .config to a text
file when the config is included in the kernel with CONFIG_IKCONFIG. By
default, the file written is called config.txt, but it can be any user
supplied filename as well. If the kernel config is in a module
(configs.ko), then it can be loaded along with symbols for the module
loaded with 'lx-symbols' and then this command will still work.
Obviously if you have the whole vmlinux then this can also be achieved
with scripts/extract-ikconfig, but this gdb script can be useful to
confirm that the memory contents of the config in memory and the vmlinux
contents on disk match what is expected.
[swboyd@chromium.org: v2]
Link: http://lkml.kernel.org/r/20190329220844.38234-3-swboyd@chromium.org
Link: http://lkml.kernel.org/r/20190325184522.260535-3-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "gdb script for kconfig and timer list".
This is a handful of changes to the kernel's gdb scripts to do some more
debugging with kgdb. The first patch allows the vmlinux to be reloaded
from where it was specified on the command line so that this set of
scripts can be used from anywhere. The second patch adds a script to
dump the config.gz to a file on the host debugging machine. The third
patch adds some rb tree utilities and the last patch uses those rb tree
walking utilities to dump out the contents of /proc/timer_list from a
system under debug.
This patch (of 5):
If I run 'gdb <path/to/vmlinux>' and there's the vmlinux-gdb.py file
there I can properly see symbols and use the lx commands provided by the
GDB scripts. But once I run 'lx-symbols' at the command prompt, gdb
reloads the vmlinux symbols assuming that this script was run from the
directory that has vmlinux at the root. That isn't always true, but we
could just look and see what symbols were already loaded and use that
instead. Let's do that so this can work by being invoked anywhere.
Link: http://lkml.kernel.org/r/20190325184522.260535-2-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch implements the PPS ECHO functionality for pps-gpio, that
sysfs claims is available already.
Configuration is done via device tree bindings.
No changes are made to userspace interfaces.
This patch was originally written by Lukas Senger as part of a masters
thesis project and modified for inclusion into the linux kernel by Tom
Burkart.
Link: http://lkml.kernel.org/r/20190324043305.6627-4-tom@aussec.com
Signed-off-by: Tom Burkart <tom@aussec.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Lukas Senger <lukas@fridolin.com>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch implements the device tree binding changes required for the
PPS ECHO functionality for pps-gpio, that sysfs claims is available
already.
It adds two DT properties for configuring the PPS ECHO functionality.
This patch is provided separated from the rest of the patch per
Documentation/devicetree/bindings/submitting-patches.txt.
This patch was originally written by Lukas Senger as part of a masters
thesis project and modified for inclusion into the linux kernel by Tom
Burkart.
Link: http://lkml.kernel.org/r/20190324043305.6627-3-tom@aussec.com
Signed-off-by: Tom Burkart <tom@aussec.com>
Signed-off-by: Lukas Senger <lukas@fridolin.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch changes the GPIO access for the pps-gpio driver from the
integer based API to the descriptor based API.
The integer based API is considered deprecated and the descriptor based
API is the preferred way to access GPIOs as per
Documentation/driver-api/gpio/intro.rst
No changes are made to userspace interfaces.
Link: http://lkml.kernel.org/r/20190324043305.6627-2-tom@aussec.com
Signed-off-by: Tom Burkart <tom@aussec.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Reviewed-by: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Lukas Senger <lukas@fridolin.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow specifying reboot_mode for panic only. This is needed on systems
where ramoops is used to store panic logs, and user wants to use warm
reset to preserve those, while still having cold reset on normal
reboots.
Link: http://lkml.kernel.org/r/20190322004735.27702-1-aaro.koskinen@iki.fi
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When kernel panic happens, it will first print the panic call stack,
then the ending msg like:
[ 35.743249] ---[ end Kernel panic - not syncing: Fatal exception
[ 35.749975] ------------[ cut here ]------------
The above message are very useful for debugging.
But if system is configured to not reboot on panic, say the
"panic_timeout" parameter equals 0, it will likely print out many noisy
message like WARN() call stack for each and every CPU except the panic
one, messages like below:
WARNING: CPU: 1 PID: 280 at kernel/sched/core.c:1198 set_task_cpu+0x183/0x190
Call Trace:
<IRQ>
try_to_wake_up
default_wake_function
autoremove_wake_function
__wake_up_common
__wake_up_common_lock
__wake_up
wake_up_klogd_work_func
irq_work_run_list
irq_work_tick
update_process_times
tick_sched_timer
__hrtimer_run_queues
hrtimer_interrupt
smp_apic_timer_interrupt
apic_timer_interrupt
For people working in console mode, the screen will first show the panic
call stack, but immediately overridden by these noisy extra messages,
which makes debugging much more difficult, as the original context gets
lost on screen.
Also these noisy messages will confuse some users, as I have seen many bug
reporters posted the noisy message into bugzilla, instead of the real
panic call stack and context.
Adding a flag "suppress_printk" which gets set in panic() to avoid those
noisy messages, without changing current kernel behavior that both panic
blinking and sysrq magic key can work as is, suggested by Petr Mladek.
To verify this, make sure kernel is not configured to reboot on panic and
in console
# echo c > /proc/sysrq-trigger
to see if console only prints out the panic call stack.
Link: http://lkml.kernel.org/r/1551430186-24169-1-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
LLVM uses profiling data that's deliberately similar to GCC, but has a
very different way of exporting that data. LLVM calls llvm_gcov_init()
once per module, and provides a couple of callbacks that we can use to
ask for more data.
We care about the "writeout" callback, which in turn calls back into
compiler-rt/this module to dump all the gathered coverage data to disk:
llvm_gcda_start_file()
llvm_gcda_emit_function()
llvm_gcda_emit_arcs()
llvm_gcda_emit_function()
llvm_gcda_emit_arcs()
[... repeats for each function ...]
llvm_gcda_summary_info()
llvm_gcda_end_file()
This design is much more stateless and unstructured than gcc's, and is
intended to run at process exit. This forces us to keep some local
state about which module we're dealing with at the moment. On the other
hand, it also means we don't depend as much on how LLVM represents
profiling data internally.
See LLVM's lib/Transforms/Instrumentation/GCOVProfiling.cpp for more
details on how this works, particularly GCOVProfiler::emitProfileArcs(),
GCOVProfiler::insertCounterWriteout(), and GCOVProfiler::insertFlush().
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20190417225328.208129-1-trong@android.com
Signed-off-by: Greg Hackmann <ghackmann@android.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Tri Vo <trong@android.com>
Co-developed-by: Nick Desaulniers <ndesaulniers@google.com>
Co-developed-by: Tri Vo <trong@android.com>
Tested-by: Trilok Soni <tsoni@quicinc.com>
Tested-by: Prasad Sodagudi <psodagud@quicinc.com>
Tested-by: Tri Vo <trong@android.com>
Tested-by: Daniel Mentz <danielmentz@google.com>
Tested-by: Petri Gynther <pgynther@google.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
