sched/cpuacct: Remove redundant RCU read lock

The cpuacct_account_field() and it's cgroup v2 wrapper
cgroup_account_cputime_field() is only called from cputime
in task_group_account_field(), which i

sched/cpuacct: Remove redundant RCU read lock

The cpuacct_account_field() and it's cgroup v2 wrapper
cgroup_account_cputime_field() is only called from cputime
in task_group_account_field(), which is already in RCU read-side
critical section. So remove these redundant RCU read lock.

Suggested-by: Tejun Heo <[email protected]>
Signed-off-by: Chengming Zhou <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

sched/cpuacct: Optimize away RCU read lock

Since cpuacct_charge() is called from the scheduler update_curr(),
we must already have rq lock held, then the RCU read lock can
be optimized away.

And do

sched/cpuacct: Optimize away RCU read lock

Since cpuacct_charge() is called from the scheduler update_curr(),
we must already have rq lock held, then the RCU read lock can
be optimized away.

And do the same thing in it's wrapper cgroup_account_cputime(),
but we can't use lockdep_assert_rq_held() there, which defined
in kernel/sched/sched.h.

Suggested-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Chengming Zhou <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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sched/cpuacct: Fix charge percpu cpuusage

The cpuacct_account_field() is always called by the current task
itself, so it's ok to use __this_cpu_add() to charge the tick time.

But cpuacct_charge() m

sched/cpuacct: Fix charge percpu cpuusage

The cpuacct_account_field() is always called by the current task
itself, so it's ok to use __this_cpu_add() to charge the tick time.

But cpuacct_charge() maybe called by update_curr() in load_balance()
on a random CPU, different from the CPU on which the task is running.
So __this_cpu_add() will charge that cputime to a random incorrect CPU.

Fixes: 73e6aafd9ea8 ("sched/cpuacct: Simplify the cpuacct code")
Reported-by: Minye Zhu <[email protected]>
Signed-off-by: Chengming Zhou <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

sched/headers: Introduce kernel/sched/build_utility.c and build multiple .c files there

Collect all utility functionality source code files into a single kernel/sched/build_utility.c file,
via #incl

sched/headers: Introduce kernel/sched/build_utility.c and build multiple .c files there

Collect all utility functionality source code files into a single kernel/sched/build_utility.c file,
via #include-ing the .c files:

kernel/sched/clock.c
kernel/sched/completion.c
kernel/sched/loadavg.c
kernel/sched/swait.c
kernel/sched/wait_bit.c
kernel/sched/wait.c

CONFIG_CPU_FREQ:
kernel/sched/cpufreq.c

CONFIG_CPU_FREQ_GOV_SCHEDUTIL:
kernel/sched/cpufreq_schedutil.c

CONFIG_CGROUP_CPUACCT:
kernel/sched/cpuacct.c

CONFIG_SCHED_DEBUG:
kernel/sched/debug.c

CONFIG_SCHEDSTATS:
kernel/sched/stats.c

CONFIG_SMP:
kernel/sched/cpupri.c
kernel/sched/stop_task.c
kernel/sched/topology.c

CONFIG_SCHED_CORE:
kernel/sched/core_sched.c

CONFIG_PSI:
kernel/sched/psi.c

CONFIG_MEMBARRIER:
kernel/sched/membarrier.c

CONFIG_CPU_ISOLATION:
kernel/sched/isolation.c

CONFIG_SCHED_AUTOGROUP:
kernel/sched/autogroup.c

The goal is to amortize the 60+ KLOC header bloat from over a dozen build units into
a single build unit.

The build time of build_utility.c also roughly matches the build time of core.c and
fair.c - allowing better load-balancing of scheduler-only rebuilds.

Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Peter Zijlstra <[email protected]>

show more ...

sched/cpuacct: Make user/system times in cpuacct.stat more precise

cpuacct.stat shows user time based on raw random precision tick
based counters. Use cputime_addjust() to scale these values against

sched/cpuacct: Make user/system times in cpuacct.stat more precise

cpuacct.stat shows user time based on raw random precision tick
based counters. Use cputime_addjust() to scale these values against the
total runtime accounted by the scheduler, like we already do
for user/system times in /proc/<pid>/stat.

Signed-off-by: Andrey Ryabinin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Jordan <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

sched/cpuacct: Fix user/system in shown cpuacct.usage*

cpuacct has 2 different ways of accounting and showing user
and system times.

The first one uses cpuacct_account_field() to account times
and

sched/cpuacct: Fix user/system in shown cpuacct.usage*

cpuacct has 2 different ways of accounting and showing user
and system times.

The first one uses cpuacct_account_field() to account times
and cpuacct.stat file to expose them. And this one seems to work ok.

The second one is uses cpuacct_charge() function for accounting and
set of cpuacct.usage* files to show times. Despite some attempts to
fix it in the past it still doesn't work. Sometimes while running KVM
guest the cpuacct_charge() accounts most of the guest time as
system time. This doesn't match with user&system times shown in
cpuacct.stat or proc/<pid>/stat.

Demonstration:
# git clone https://github.com/aryabinin/kvmsample
# make
# mkdir /sys/fs/cgroup/cpuacct/test
# echo $$ > /sys/fs/cgroup/cpuacct/test/tasks
# ./kvmsample &
# for i in {1..5}; do cat /sys/fs/cgroup/cpuacct/test/cpuacct.usage_sys; sleep 1; done
1976535645
2979839428
3979832704
4983603153
5983604157

Use cpustats accounted in cpuacct_account_field() as the source
of user/sys times for cpuacct.usage* files. Make cpuacct_charge()
to account only summary execution time.

Fixes: d740037fac70 ("sched/cpuacct: Split usage accounting into user_usage and sys_usage")
Signed-off-by: Andrey Ryabinin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Jordan <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Cc: <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

cpuacct: Convert BUG_ON() to WARN_ON_ONCE()

Replace fatal BUG_ON() with more safe WARN_ON_ONCE() in cpuacct_cpuusage_read().

Signed-off-by: Andrey Ryabinin <[email protected]>
Signed-off-by: Pet

cpuacct: Convert BUG_ON() to WARN_ON_ONCE()

Replace fatal BUG_ON() with more safe WARN_ON_ONCE() in cpuacct_cpuusage_read().

Signed-off-by: Andrey Ryabinin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Jordan <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

sched: Wrap rq::lock access

In preparation of playing games with rq->lock, abstract the thing
using an accessor.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Tested-by: Don Hiatt <d

sched: Wrap rq::lock access

In preparation of playing games with rq->lock, abstract the thing
using an accessor.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Tested-by: Don Hiatt <[email protected]>
Tested-by: Hongyu Ning <[email protected]>
Tested-by: Vincent Guittot <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

sched: Fix various typos

Fix ~42 single-word typos in scheduler code comments.

We have accumulated a few fun ones over the years. :-)

Signed-off-by: Ingo Molnar <[email protected]>
Cc: Peter Zijlst

sched: Fix various typos

Fix ~42 single-word typos in scheduler code comments.

We have accumulated a few fun ones over the years. :-)

Signed-off-by: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Vincent Guittot <[email protected]>
Cc: Dietmar Eggemann <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Ben Segall <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: [email protected]

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sched/cpuacct: Fix charge cpuacct.usage_sys

The user_mode(task_pt_regs(tsk)) always return true for
user thread, and false for kernel thread. So it means that
the cpuacct.usage_sys is the time that

sched/cpuacct: Fix charge cpuacct.usage_sys

The user_mode(task_pt_regs(tsk)) always return true for
user thread, and false for kernel thread. So it means that
the cpuacct.usage_sys is the time that kernel thread uses
not the time that thread uses in the kernel mode. We can
try get_irq_regs() first, if it is NULL, then we can fall
back to task_pt_regs().

Signed-off-by: Muchun Song <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

sched/cpuacct: Use __this_cpu_add() instead of this_cpu_ptr()

The cpuacct_charge() and cpuacct_account_field() are called with
rq->lock held, and this means preemption(and IRQs) are indeed
disabled,

sched/cpuacct: Use __this_cpu_add() instead of this_cpu_ptr()

The cpuacct_charge() and cpuacct_account_field() are called with
rq->lock held, and this means preemption(and IRQs) are indeed
disabled, so it is safe to use __this_cpu_*() to allow for better
code-generation.

Signed-off-by: Muchun Song <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

sched/headers: Simplify and clean up header usage in the scheduler

Do the following cleanups and simplifications:

- sched/sched.h already includes <asm/paravirt.h>, so no need to
include it in

sched/headers: Simplify and clean up header usage in the scheduler

Do the following cleanups and simplifications:

- sched/sched.h already includes <asm/paravirt.h>, so no need to
include it in sched/core.c again.

- order the <linux/sched/*.h> headers alphabetically

- add all <linux/sched/*.h> headers to kernel/sched/sched.h

- remove all unnecessary includes from the .c files that
are already included in kernel/sched/sched.h.

Finally, make all scheduler .c files use a single common header:

#include "sched.h"

... which now contains a union of the relied upon headers.

This makes the various .c files easier to read and easier to handle.

Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched: Clean up and harmonize the coding style of the scheduler code base

A good number of small style inconsistencies have accumulated
in the scheduler core, so do a pass over them to harmonize
all

sched: Clean up and harmonize the coding style of the scheduler code base

A good number of small style inconsistencies have accumulated
in the scheduler core, so do a pass over them to harmonize
all these details:

- fix speling in comments,

- use curly braces for multi-line statements,

- remove unnecessary parentheses from integer literals,

- capitalize consistently,

- remove stray newlines,

- add comments where necessary,

- remove invalid/unnecessary comments,

- align structure definitions and other data types vertically,

- add missing newlines for increased readability,

- fix vertical tabulation where it's misaligned,

- harmonize preprocessor conditional block labeling
and vertical alignment,

- remove line-breaks where they uglify the code,

- add newline after local variable definitions,

No change in functionality:

md5:
1191fa0a890cfa8132156d2959d7e9e2 built-in.o.before.asm
1191fa0a890cfa8132156d2959d7e9e2 built-in.o.after.asm

Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

sched/cputime: Convert kcpustat to nsecs

Kernel CPU stats are stored in cputime_t which is an architecture
defined type, and hence a bit opaque and requiring accessors and mutators
for any operation

sched/cputime: Convert kcpustat to nsecs

Kernel CPU stats are stored in cputime_t which is an architecture
defined type, and hence a bit opaque and requiring accessors and mutators
for any operation.

Converting them to nsecs simplifies the code and is one step toward
the removal of cputime_t in the core code.

Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Stanislaw Gruszka <[email protected]>
Cc: Wanpeng Li <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/cpuacct: Avoid %lld seq_printf warning

For s390 kernel builds I keep getting this warning:

kernel/sched/cpuacct.c: In function 'cpuacct_stats_show':
kernel/sched/cpuacct.c:298:25: warning:

sched/cpuacct: Avoid %lld seq_printf warning

For s390 kernel builds I keep getting this warning:

kernel/sched/cpuacct.c: In function 'cpuacct_stats_show':
kernel/sched/cpuacct.c:298:25: warning: format '%lld' expects argument of type 'long long int', but argument 4 has type 'clock_t {aka long int}' [-Wformat=]
seq_printf(sf, "%s %lld\n",

Silence the warning by adding an explicit cast.

Signed-off-by: Martin Schwidefsky <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together

In current code, we can get cpuacct data from several files,
but each file has various limitations.

For example:

- We can

sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together

In current code, we can get cpuacct data from several files,
but each file has various limitations.

For example:

- We can get CPU usage in user and kernel mode via cpuacct.stat,
but we can't get detailed data about each CPU.

- We can get each CPU's kernel mode usage in cpuacct.usage_percpu_sys,
but we can't get user mode usage data at the same time.

This patch introduces cpuacct.usage_all, to show all detailed CPU
accounting data together:

# cat cpuacct.usage_all
cpu user system
0 3809760299 5807968992
1 3250329855 454612211
..

Signed-off-by: Zhao Lei <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/7744460969edd7caaf0e903592ee52353ed9bdd6.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()

In cpuacct_stats_show() we currently we have copies of similar code,
for each cpustat(system/user) variant.

Use a loop instead to

sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()

In cpuacct_stats_show() we currently we have copies of similar code,
for each cpustat(system/user) variant.

Use a loop instead to consolidate the code. This will also work better
if we extend the CPUACCT_STAT_NSTATS type.

Signed-off-by: Zhao Lei <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/b0597d4224655e9f333f1a6224ed9654c7d7d36a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums

These two types have similar function, no need to separate them.

Signed-off-by: Zhao Lei <[email protected]>
Cc: KOSAKI Mo

sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums

These two types have similar function, no need to separate them.

Signed-off-by: Zhao Lei <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/436748885270d64363c7dc67167507d486c2057a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

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sched/cpuacct: Check for NULL when using task_pt_regs()

task_pt_regs() can return NULL for kernel threads, so add a check.
This fixes an oops at boot on ppc64.

Reported-and-Tested-by: Srikar Dronam

sched/cpuacct: Check for NULL when using task_pt_regs()

task_pt_regs() can return NULL for kernel threads, so add a check.
This fixes an oops at boot on ppc64.

Reported-and-Tested-by: Srikar Dronamraju <[email protected]>
Tested-by: Zhao Lei <[email protected]>
Signed-off-by: Anton Blanchard <[email protected]>
Acked-by: Zhao Lei <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/20160406215950.04bc3f0b@kryten
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/cpuacct: Split usage accounting into user_usage and sys_usage

Sometimes, cpuacct.usage is not detailed enough to see how much CPU
usage a group had. We want to know how much time it used in us

sched/cpuacct: Split usage accounting into user_usage and sys_usage

Sometimes, cpuacct.usage is not detailed enough to see how much CPU
usage a group had. We want to know how much time it used in user mode
and how much in kernel mode.

This patch introduces more files to give this information:

# ls /sys/fs/cgroup/cpuacct/cpuacct.usage*
/sys/fs/cgroup/cpuacct/cpuacct.usage
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu
/sys/fs/cgroup/cpuacct/cpuacct.usage_user
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_user
/sys/fs/cgroup/cpuacct/cpuacct.usage_sys
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_sys

... while keeping the ABI with the existing counter.

Signed-off-by: Dongsheng Yang <[email protected]>
[ Ported to newer kernels. ]
Signed-off-by: Zhao Lei <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/aa171da036b520b51c79549e9b3215d29473f19d.1458635566.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

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sched/cpuacct: Show all possible CPUs in cpuacct output

Current code show stats of online CPUs in cpuacct.statcpus,
show stats of present cpus in cpuacct.usage(_percpu), and using
present CPUs for s

sched/cpuacct: Show all possible CPUs in cpuacct output

Current code show stats of online CPUs in cpuacct.statcpus,
show stats of present cpus in cpuacct.usage(_percpu), and using
present CPUs for setting cpuacct.usage.

It will cause inconsistent result when a CPU is online or offline
or hotpluged.

We should always use possible CPUs to avoid above problem.

Here are the contents of a cpuacct.usage_percpu sysfs file,
on a 4 CPU system with maxcpus=32:

Before the patch:
# cat cpuacct.usage_percpu
2456565 411435 1052897 832584

After the patch:
# cat cpuacct.usage_percpu
2456565 411435 1052897 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: Zhao Lei <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/a11d56cef12d0b4807f8be3a46bf9798c3014d59.1458635566.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

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sched/cpuacct: Simplify the cpuacct code

- Use for() instead of while() loop in some functions
to make the code simpler.

- Use this_cpu_ptr() instead of per_cpu_ptr() to make the code
clean

sched/cpuacct: Simplify the cpuacct code

- Use for() instead of while() loop in some functions
to make the code simpler.

- Use this_cpu_ptr() instead of per_cpu_ptr() to make the code
cleaner and a bit faster.

Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: Zhao Lei <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/d8a7ef9592f55224630cb26dea239f05b6398a4e.1458187654.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <[email protected]>

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sched/cpuacct: Rename parameter in cpuusage_write() for readability

The name of the 'reset' parameter to cpuusage_write() is quite confusing,
because the only valid value we allow is '0', so !reset

sched/cpuacct: Rename parameter in cpuusage_write() for readability

The name of the 'reset' parameter to cpuusage_write() is quite confusing,
because the only valid value we allow is '0', so !reset is actually the
case that resets ...

Rename it to 'val' and explain it in a comment that we only allow 0.

Signed-off-by: Dongsheng Yang <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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cgroup: convert cgroup_subsys flag fields to bool bitfields

Signed-off-by: Tejun Heo <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <peterz@i

cgroup: convert cgroup_subsys flag fields to bool bitfields

Signed-off-by: Tejun Heo <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>

show more ...