linux_dsm_epyc7002/kernel/sched
Liangyan 5e2d2cc258 sched/fair: Don't assign runtime for throttled cfs_rq
do_sched_cfs_period_timer() will refill cfs_b runtime and call
distribute_cfs_runtime to unthrottle cfs_rq, sometimes cfs_b->runtime
will allocate all quota to one cfs_rq incorrectly, then other cfs_rqs
attached to this cfs_b can't get runtime and will be throttled.

We find that one throttled cfs_rq has non-negative
cfs_rq->runtime_remaining and cause an unexpetced cast from s64 to u64
in snippet:

  distribute_cfs_runtime() {
    runtime = -cfs_rq->runtime_remaining + 1;
  }

The runtime here will change to a large number and consume all
cfs_b->runtime in this cfs_b period.

According to Ben Segall, the throttled cfs_rq can have
account_cfs_rq_runtime called on it because it is throttled before
idle_balance, and the idle_balance calls update_rq_clock to add time
that is accounted to the task.

This commit prevents cfs_rq to be assgined new runtime if it has been
throttled until that distribute_cfs_runtime is called.

Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: shanpeic@linux.alibaba.com
Cc: stable@vger.kernel.org
Cc: xlpang@linux.alibaba.com
Fixes: d3d9dc3302 ("sched: Throttle entities exceeding their allowed bandwidth")
Link: https://lkml.kernel.org/r/20190826121633.6538-1-liangyan.peng@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-09-03 08:55:07 +02:00
..
autogroup.c sched/autogroup: Make autogroup_path() always available 2019-06-24 19:23:40 +02:00
autogroup.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
clock.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
completion.c sched/Documentation: Update wake_up() & co. memory-barrier guarantees 2018-07-17 09:30:34 +02:00
core.c sched/core: Schedule new worker even if PI-blocked 2019-08-19 10:57:26 +02:00
cpuacct.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpudeadline.c Linux 5.2-rc5 2019-06-17 12:12:27 +02:00
cpudeadline.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpufreq_schedutil.c cpufreq: schedutil: Don't skip freq update when limits change 2019-08-10 13:53:19 +02:00
cpufreq.c sched/cpufreq: Annotate cpufreq_update_util_data pointer with __rcu 2019-04-03 12:34:31 +02:00
cpupri.c Linux 5.2-rc5 2019-06-17 12:12:27 +02:00
cpupri.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cputime.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
deadline.c sched/deadline: Fix double accounting of rq/running bw in push & pull 2019-08-06 12:49:18 +02:00
debug.c Linux 5.2-rc6 2019-06-24 19:19:53 +02:00
fair.c sched/fair: Don't assign runtime for throttled cfs_rq 2019-09-03 08:55:07 +02:00
features.h sched/fair: Replace source_load() & target_load() with weighted_cpuload() 2019-06-03 11:49:39 +02:00
idle.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
isolation.c KVM: LAPIC: Inject timer interrupt via posted interrupt 2019-07-20 09:00:40 +02:00
loadavg.c sched: loadavg: make calc_load_n() public 2018-10-26 16:26:32 -07:00
Makefile psi: pressure stall information for CPU, memory, and IO 2018-10-26 16:26:32 -07:00
membarrier.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
pelt.c sched/debug: Add new tracepoint to track PELT at se level 2019-06-24 19:23:42 +02:00
pelt.h sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity() 2019-06-24 19:23:39 +02:00
psi.c psi: get poll_work to run when calling poll syscall next time 2019-08-24 19:48:42 -07:00
rt.c sched/cpufreq, sched/uclamp: Add clamps for FAIR and RT tasks 2019-06-24 19:23:48 +02:00
sched-pelt.h sched/fair: Fix "runnable_avg_yN_inv" not used warnings 2019-06-17 12:15:58 +02:00
sched.h sched/uclamp: Add uclamp support to energy_compute() 2019-06-24 19:23:49 +02:00
stats.c proc: introduce proc_create_seq{,_data} 2018-05-16 07:23:35 +02:00
stats.h psi: make disabling/enabling easier for vendor kernels 2018-11-30 14:56:14 -08:00
stop_task.c sched: Clean up and harmonize the coding style of the scheduler code base 2018-03-03 15:50:21 +01:00
swait.c kernel/sched/: remove caller signal_pending branch predictions 2019-01-04 13:13:48 -08:00
topology.c sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity() 2019-06-24 19:23:39 +02:00
wait_bit.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
wait.c sched/wait: Deduplicate code with do-while 2019-06-24 19:23:40 +02:00