linux/kernel/sched
Andrey Ryabinin dd02d4234c 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: d740037fac ("sched/cpuacct: Split usage accounting into user_usage and sys_usage")
Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211115164607.23784-3-arbn@yandex-team.com
2021-11-23 09:55:22 +01:00
..
autogroup.c sched/fair: Prevent dead task groups from regaining cfs_rq's 2021-11-11 13:09:33 +01:00
autogroup.h
clock.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
completion.c completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all() 2020-03-23 18:40:25 +01:00
core_sched.c sched/core: Forced idle accounting 2021-11-17 14:49:00 +01:00
core.c sched/core: Forced idle accounting 2021-11-17 14:49:00 +01:00
cpuacct.c sched/cpuacct: Fix user/system in shown cpuacct.usage* 2021-11-23 09:55:22 +01:00
cpudeadline.c sched,rt: Use the full cpumask for balancing 2020-11-10 18:39:00 +01:00
cpudeadline.h
cpufreq_schedutil.c cpufreq: schedutil: Use kobject release() method to free sugov_tunables 2021-08-06 15:34:55 +02:00
cpufreq.c cpufreq: Avoid leaving stale IRQ work items during CPU offline 2019-12-12 17:59:43 +01:00
cpupri.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
cpupri.h sched/cpupri: Add CPUPRI_HIGHER 2020-10-29 11:00:30 +01:00
cputime.c cputime, cpuacct: Include guest time in user time in cpuacct.stat 2021-11-23 09:55:22 +01:00
deadline.c sched/dl: Support schedstats for deadline sched class 2021-10-05 15:51:53 +02:00
debug.c sched/core: Forced idle accounting 2021-11-17 14:49:00 +01:00
fair.c sched/core: Forced idle accounting 2021-11-17 14:49:00 +01:00
features.h sched: Disable TTWU_QUEUE on RT 2021-10-05 15:52:12 +02:00
idle.c sched/idle: Make the idle timer expire in hard interrupt context 2021-09-09 10:36:16 +02:00
isolation.c sched/isolation: Reconcile rcu_nocbs= and nohz_full= 2021-05-13 14:12:47 +02:00
loadavg.c sched: Make multiple runqueue task counters 32-bit 2021-05-12 21:34:17 +02:00
Makefile sched: Disable -Wunused-but-set-variable 2021-10-15 11:25:15 +02:00
membarrier.c sched/membarrier: fix missing local execution of ipi_sync_rq_state() 2021-03-06 12:40:21 +01:00
pelt.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
pelt.h Merge branch 'sched/urgent' into sched/core, to resolve conflicts 2021-06-18 11:31:25 +02:00
psi.c psi: Fix PSI_MEM_FULL state when tasks are in memstall and doing reclaim 2021-11-17 14:49:00 +01:00
rt.c sched/fair: Prevent dead task groups from regaining cfs_rq's 2021-11-11 13:09:33 +01:00
sched-pelt.h
sched.h sched/core: Forced idle accounting 2021-11-17 14:49:00 +01:00
smp.h sched/headers: Split out open-coded prototypes into kernel/sched/smp.h 2020-05-28 11:03:20 +02:00
stats.c sched: Introduce task block time in schedstats 2021-10-05 15:51:48 +02:00
stats.h psi: Fix PSI_MEM_FULL state when tasks are in memstall and doing reclaim 2021-11-17 14:49:00 +01:00
stop_task.c sched: Make struct sched_statistics independent of fair sched class 2021-10-05 15:51:45 +02:00
swait.c sched/swait: Prepare usage in completions 2020-03-21 16:00:23 +01:00
topology.c Merge branch 'akpm' (patches from Andrew) 2021-11-06 14:08:17 -07:00
wait_bit.c sched/wait: fix ___wait_var_event(exclusive) 2019-12-17 13:32:50 +01:00
wait.c rq-qos: fix missed wake-ups in rq_qos_throttle try two 2021-06-08 15:12:57 -06:00