Hailong Liu f3d133ee0a sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHARE ... NO_RT_RUNTIME_SHARE feature is used to prevent a CPU borrow enough runtime with a spin-rt-task. However, if RT_RUNTIME_SHARE feature is enabled and rt_rq has borrowd enough rt_runtime at the beginning, rt_runtime can't be restored to its initial bandwidth rt_runtime after we disable RT_RUNTIME_SHARE. E.g. on my PC with 4 cores, procedure to reproduce: 1) Make sure RT_RUNTIME_SHARE is enabled cat /sys/kernel/debug/sched_features GENTLE_FAIR_SLEEPERS START_DEBIT NO_NEXT_BUDDY LAST_BUDDY CACHE_HOT_BUDDY WAKEUP_PREEMPTION NO_HRTICK NO_DOUBLE_TICK LB_BIAS NONTASK_CAPACITY TTWU_QUEUE NO_SIS_AVG_CPU SIS_PROP NO_WARN_DOUBLE_CLOCK RT_PUSH_IPI RT_RUNTIME_SHARE NO_LB_MIN ATTACH_AGE_LOAD WA_IDLE WA_WEIGHT WA_BIAS 2) Start a spin-rt-task ./loop_rr & 3) set affinity to the last cpu taskset -p 8 $pid_of_loop_rr 4) Observe that last cpu have borrowed enough runtime. cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 5) Disable RT_RUNTIME_SHARE echo NO_RT_RUNTIME_SHARE > /sys/kernel/debug/sched_features 6) Observe that rt_runtime can not been restored cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 This patch help to restore rt_runtime after we disable RT_RUNTIME_SHARE. Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn> Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: zhong.weidong@zte.com.cn Link: http://lkml.kernel.org/r/1531874815-39357-1-git-send-email-liu.hailong6@zte.com.cn Signed-off-by: Ingo Molnar <mingo@kernel.org>		2018-07-25 11:29:08 +02:00
..
autogroup.c	sched/autogroup: Fix possible Spectre-v1 indexing for sched_prio_to_weight[]	2018-05-05 08:34:42 +02:00
autogroup.h
clock.c
completion.c
core.c	kthread, sched/core: Fix kthread_parkme() (again...)	2018-07-03 09:17:30 +02:00
cpuacct.c
cpudeadline.c
cpudeadline.h
cpufreq.c
cpufreq_schedutil.c	sched/rt: Fix call to cpufreq_update_util()	2018-07-03 09:17:28 +02:00
cpupri.c
cpupri.h
cputime.c
deadline.c	sched/deadline: Update rq_clock of later_rq when pushing a task	2018-07-25 11:29:08 +02:00
debug.c	proc: introduce proc_create_seq{,_data}	2018-05-16 07:23:35 +02:00
fair.c	sched/util_est: Fix util_est_dequeue() for throttled cfs_rq	2018-07-03 09:17:30 +02:00
features.h
idle.c	sched: idle: Select idle state before stopping the tick	2018-04-09 11:54:07 +02:00
isolation.c
loadavg.c
Makefile
membarrier.c
rt.c	sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHARE	2018-07-25 11:29:08 +02:00
sched-pelt.h
sched.h	sched/fair: Fix bandwidth timer clock drift condition	2018-07-03 09:17:29 +02:00
stats.c	proc: introduce proc_create_seq{,_data}	2018-05-16 07:23:35 +02:00
stats.h
stop_task.c
swait.c
topology.c	sched/topology: Check variable group before dereferencing it	2018-07-25 11:25:07 +02:00
wait.c
wait_bit.c