linux/kernel/sched
Cheng Yu 49217ea147 sched/core: Fix incorrect initialization of the 'burst' parameter in cpu_max_write()
In the cgroup v2 CPU subsystem, assuming we have a
cgroup named 'test', and we set cpu.max and cpu.max.burst:

    # echo 1000000 > /sys/fs/cgroup/test/cpu.max
    # echo 1000000 > /sys/fs/cgroup/test/cpu.max.burst

then we check cpu.max and cpu.max.burst:

    # cat /sys/fs/cgroup/test/cpu.max
    1000000 100000
    # cat /sys/fs/cgroup/test/cpu.max.burst
    1000000

Next we set cpu.max again and check cpu.max and
cpu.max.burst:

    # echo 2000000 > /sys/fs/cgroup/test/cpu.max
    # cat /sys/fs/cgroup/test/cpu.max
    2000000 100000

    # cat /sys/fs/cgroup/test/cpu.max.burst
    1000

... we find that the cpu.max.burst value changed unexpectedly.

In cpu_max_write(), the unit of the burst value returned
by tg_get_cfs_burst() is microseconds, while in cpu_max_write(),
the burst unit used for calculation should be nanoseconds,
which leads to the bug.

To fix it, get the burst value directly from tg->cfs_bandwidth.burst.

Fixes: f4183717b3 ("sched/fair: Introduce the burstable CFS controller")
Reported-by: Qixin Liao <liaoqixin@huawei.com>
Signed-off-by: Cheng Yu <serein.chengyu@huawei.com>
Signed-off-by: Zhang Qiao <zhangqiao22@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20240424132438.514720-1-serein.chengyu@huawei.com
2024-05-17 09:53:54 +02:00
..
autogroup.c
autogroup.h
build_policy.c
build_utility.c sched/headers: Remove duplicate header inclusions 2023-10-03 21:27:55 +02:00
clock.c Locking changes for v6.5: 2023-06-27 14:14:30 -07:00
completion.c sched: add a few helpers to wake up tasks on the current cpu 2023-07-17 16:08:08 -07:00
core_sched.c sched: Rename task_running() to task_on_cpu() 2022-09-07 21:53:47 +02:00
core.c sched/core: Fix incorrect initialization of the 'burst' parameter in cpu_max_write() 2024-05-17 09:53:54 +02:00
cpuacct.c
cpudeadline.c sched/topology: Consolidate and clean up access to a CPU's max compute capacity 2023-10-09 12:59:48 +02:00
cpudeadline.h
cpufreq_schedutil.c sched/fair: Fix frequency selection for non-invariant case 2024-01-16 10:41:25 +01:00
cpufreq.c
cpupri.c sched/rt: Fix live lock between select_fallback_rq() and RT push 2023-09-28 22:58:13 +02:00
cpupri.h
cputime.c sched/vtime: Get rid of generic vtime_task_switch() implementation 2024-04-17 13:37:20 +02:00
deadline.c sched/deadline: Introduce deadline servers 2023-11-15 09:57:51 +01:00
debug.c sched/debug: Dump domains' level 2024-05-17 09:48:25 +02:00
fair.c sched/fair: Remove stale FREQUENCY_UTIL comment 2024-05-17 09:51:54 +02:00
features.h sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true) 2023-12-23 15:59:56 +01:00
idle.c Core x86 changes for v6.9: 2024-03-11 19:53:15 -07:00
isolation.c sched/isolation: Fix boot crash when maxcpus < first housekeeping CPU 2024-04-28 10:08:21 +02:00
loadavg.c sched/balancing: Rename scheduler_tick() => sched_tick() 2024-03-12 11:59:59 +01:00
Makefile
membarrier.c RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
pelt.c sched/cpufreq: Rename arch_update_thermal_pressure() => arch_update_hw_pressure() 2024-04-24 12:08:01 +02:00
pelt.h sched/cpufreq: Rename arch_update_thermal_pressure() => arch_update_hw_pressure() 2024-04-24 12:08:01 +02:00
psi.c sched/psi: Update poll => rtpoll in relevant comments 2023-10-16 13:42:49 +02:00
rt.c sched: Unify runtime accounting across classes 2023-11-15 09:57:48 +01:00
sched-pelt.h
sched.h Scheduler changes for v6.10: 2024-05-13 17:18:51 -07:00
smp.h sched, smp: Trace smp callback causing an IPI 2023-03-24 11:01:29 +01:00
stats.c sched/debug: Increase SCHEDSTAT_VERSION to 16 2024-03-12 11:03:40 +01:00
stats.h sched/psi: Use task->psi_flags to clear in CPU migration 2022-10-30 10:12:15 +01:00
stop_task.c sched: Unify runtime accounting across classes 2023-11-15 09:57:48 +01:00
swait.c sched: add a few helpers to wake up tasks on the current cpu 2023-07-17 16:08:08 -07:00
topology.c sched/fair: Allow disabling sched_balance_newidle with sched_relax_domain_level 2024-05-17 09:48:24 +02:00
wait_bit.c
wait.c sched: remove wait bookmarks 2023-10-18 14:34:18 -07:00