kernel_optimize_test/kernel/sched
Lucas Stach 46fcc4b00c sched/deadline: Fix stale throttling on de-/boosted tasks
When a boosted task gets throttled, what normally happens is that it's
immediately enqueued again with ENQUEUE_REPLENISH, which replenishes the
runtime and clears the dl_throttled flag. There is a special case however:
if the throttling happened on sched-out and the task has been deboosted in
the meantime, the replenish is skipped as the task will return to its
normal scheduling class. This leaves the task with the dl_throttled flag
set.

Now if the task gets boosted up to the deadline scheduling class again
while it is sleeping, it's still in the throttled state. The normal wakeup
however will enqueue the task with ENQUEUE_REPLENISH not set, so we don't
actually place it on the rq. Thus we end up with a task that is runnable,
but not actually on the rq and neither a immediate replenishment happens,
nor is the replenishment timer set up, so the task is stuck in
forever-throttled limbo.

Clear the dl_throttled flag before dropping back to the normal scheduling
class to fix this issue.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200831110719.2126930-1-l.stach@pengutronix.de
2020-09-25 14:23:24 +02:00
..
autogroup.c
autogroup.h
clock.c
completion.c completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all() 2020-03-23 18:40:25 +01:00
core.c sched: Cache task_struct::flags in sched_submit_work() 2020-08-26 12:41:58 +02:00
cpuacct.c sched/cpuacct: Fix charge cpuacct.usage_sys 2020-05-19 20:34:14 +02:00
cpudeadline.c sched/deadline: Implement fallback mechanism for !fit case 2020-06-15 14:10:05 +02:00
cpudeadline.h
cpufreq_schedutil.c Power management updates for 5.9-rc1 2020-08-03 20:28:08 -07:00
cpufreq.c
cpupri.c sched/rt: cpupri_find: Trigger a full search as fallback 2020-03-20 13:06:20 +01:00
cpupri.h sched/rt: Optimize cpupri_find() on non-heterogenous systems 2020-03-06 12:57:27 +01:00
cputime.c sched/cputime: Improve cputime_adjust() 2020-06-15 14:10:00 +02:00
deadline.c sched/deadline: Fix stale throttling on de-/boosted tasks 2020-09-25 14:23:24 +02:00
debug.c sched/topology: Move sd_flag_debug out of #ifdef CONFIG_SYSCTL 2020-09-09 10:09:03 +02:00
fair.c sched/numa: Use runnable_avg to classify node 2020-09-25 14:23:24 +02:00
features.h
idle.c Merge branch 'sched/urgent' 2020-07-08 11:38:59 +02:00
isolation.c isolcpus: Affine unbound kernel threads to housekeeping cpus 2020-06-15 14:10:03 +02:00
loadavg.c sched: nohz: stop passing around unused "ticks" parameter. 2020-07-22 10:22:04 +02:00
Makefile
membarrier.c
pelt.c sched: Add a tracepoint to track rq->nr_running 2020-07-08 11:39:02 +02:00
pelt.h sched/pelt: Cleanup PELT divider 2020-06-15 14:10:06 +02:00
psi.c sched,psi: Convert to sched_set_fifo_low() 2020-06-15 14:10:25 +02:00
rt.c sched: Remove struct sched_class::next field 2020-06-25 13:45:44 +02:00
sched-pelt.h
sched.h sched: Fix use of count for nr_running tracepoint 2020-08-06 09:36:59 +02:00
smp.h sched/headers: Split out open-coded prototypes into kernel/sched/smp.h 2020-05-28 11:03:20 +02:00
stats.c
stats.h psi: Move PF_MEMSTALL out of task->flags 2020-03-20 13:06:19 +01:00
stop_task.c sched: Remove struct sched_class::next field 2020-06-25 13:45:44 +02:00
swait.c sched/swait: Prepare usage in completions 2020-03-21 16:00:23 +01:00
topology.c sched/topology: Move sd_flag_debug out of #ifdef CONFIG_SYSCTL 2020-09-09 10:09:03 +02:00
wait_bit.c
wait.c list: add "list_del_init_careful()" to go with "list_empty_careful()" 2020-08-02 20:39:44 -07:00