linux/kernel/sched
Josh Don 2cae3948ed sched: adjust sleeper credit for SCHED_IDLE entities
Give reduced sleeper credit to SCHED_IDLE entities. As a result, woken
SCHED_IDLE entities will take longer to preempt normal entities.

The benefit of this change is to make it less likely that a newly woken
SCHED_IDLE entity will preempt a short-running normal entity before it
blocks.

We still give a small sleeper credit to SCHED_IDLE entities, so that
idle<->idle competition retains some fairness.

Example: With HZ=1000, spawned four threads affined to one cpu, one of
which was set to SCHED_IDLE. Without this patch, wakeup latency for the
SCHED_IDLE thread was ~1-2ms, with the patch the wakeup latency was
~5ms.

Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Link: https://lore.kernel.org/r/20210820010403.946838-5-joshdon@google.com
2021-10-05 15:51:39 +02:00
..
autogroup.c
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: prctl() core-scheduling interface 2021-05-12 11:43:31 +02:00
core.c sched/core: Simplify core-wide task selection 2021-10-05 15:51:33 +02:00
cpuacct.c sched: Wrap rq::lock access 2021-05-12 11:43:26 +02:00
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 Scheduler updates for this cycle are: 2021-04-28 13:33:57 -07:00
deadline.c sched/deadline: Fix missing clock update in migrate_task_rq_dl() 2021-08-06 14:25:24 +02:00
debug.c sched: reduce sched slice for SCHED_IDLE entities 2021-10-05 15:51:37 +02:00
fair.c sched: adjust sleeper credit for SCHED_IDLE entities 2021-10-05 15:51:39 +02:00
features.h sched: Warn on long periods of pending need_resched 2021-04-21 13:55:41 +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: Trivial core scheduling cookie management 2021-05-12 11:43:31 +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 Merge branch 'for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2021-07-01 17:22:14 -07:00
rt.c sched/rt: Fix RT utilization tracking during policy change 2021-06-22 16:41:59 +02:00
sched-pelt.h
sched.h sched: reduce sched slice for SCHED_IDLE entities 2021-10-05 15:51:37 +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 sched: Fix various typos 2021-03-22 00:11:52 +01:00
stats.h sched: Introduce task_is_running() 2021-06-18 11:43:07 +02:00
stop_task.c sched: Introduce sched_class::pick_task() 2021-05-12 11:43:28 +02:00
swait.c sched/swait: Prepare usage in completions 2020-03-21 16:00:23 +01:00
topology.c sched/topology: Skip updating masks for non-online nodes 2021-08-20 12:32:57 +02:00
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