diff options
| author | Pavankumar Kondeti <pkondeti@codeaurora.org> | 2016-03-04 13:36:43 +0530 |
|---|---|---|
| committer | Joonwoo Park <joonwoop@codeaurora.org> | 2016-06-23 14:03:24 -0700 |
| commit | a68e39b7fd87886ebbf65cc0da4f5fb010a65f58 (patch) | |
| tree | d547ad9d8c8793fa658cd3d55d95f34be4ab2ff3 /kernel | |
| parent | 7d1fabcef82e138c38c84144457a5e962381b0b1 (diff) | |
sched: break the forever prev_cpu selection preference
The select_best_cpu() algorithm selects the previous CPU as the target
CPU if the task did not sleep for more than 2 msec (controlled by
/proc/sys/kernel/sched_select_prev_cpu_us). The complete CPU search is
not done for a long time for tasks which sleeps for a short duration
in between the long execution slices. Enforce a 100 msec threshold since
the last selection time to run the complete algorithm.
CRs-Fixed: 984463
Change-Id: I329eecc6bae8f130cd5598f6cee8ca5a01391cca
[joonwoop@codeaurora.org: fixed conflict in bias_to_prev_cpu() and sched.h
where CONFIG_SCHED_QHMP used to be.]
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 1 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 9 |
2 files changed, 10 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index aaa4f5e258b1..86cb7ec53137 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3056,6 +3056,7 @@ static inline void mark_task_starting(struct task_struct *p) wallclock = sched_ktime_clock(); p->ravg.mark_start = p->last_wake_ts = wallclock; + p->last_cpu_selected_ts = wallclock; p->last_switch_out_ts = 0; update_task_cpu_cycles(p, cpu_of(rq)); } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b9ee3dc4a1a6..859416724e5a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2678,6 +2678,9 @@ static unsigned int __read_mostly sched_short_sleep_task_threshold = 2000 * NSEC_PER_USEC; unsigned int __read_mostly sysctl_sched_select_prev_cpu_us = 2000; +static unsigned int __read_mostly +sched_long_cpu_selection_threshold = 100 * NSEC_PER_MSEC; + unsigned int __read_mostly sysctl_sched_restrict_cluster_spill; void update_up_down_migrate(void) @@ -3455,6 +3458,7 @@ bias_to_prev_cpu(struct cpu_select_env *env, struct cluster_cpu_stats *stats) struct sched_cluster *cluster; if (env->boost_type != SCHED_BOOST_NONE || env->reason || + !task->ravg.mark_start || env->need_idle || !sched_short_sleep_task_threshold) return false; @@ -3463,6 +3467,10 @@ bias_to_prev_cpu(struct cpu_select_env *env, struct cluster_cpu_stats *stats) unlikely(!cpu_active(prev_cpu))) return false; + if (task->ravg.mark_start - task->last_cpu_selected_ts >= + sched_long_cpu_selection_threshold) + return false; + /* * This function should be used by task wake up path only as it's * assuming p->last_switch_out_ts as last sleep time. @@ -3604,6 +3612,7 @@ retry: if (stats.best_capacity_cpu >= 0) target = stats.best_capacity_cpu; } + p->last_cpu_selected_ts = sched_ktime_clock(); out: rcu_read_unlock(); |