diff options
| author | Srivatsa Vaddagiri <vatsa@codeaurora.org> | 2015-01-06 15:36:28 +0530 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-23 20:01:33 -0700 |
| commit | 207d78dd263114ccf6e04581f43e4dc99e7b068d (patch) | |
| tree | 848853dc9722d1476e79fd362e75b3fa1d5777b4 /kernel | |
| parent | b0ccf5db311522b91cb770ce4c245a3f029b4ad5 (diff) | |
sched: Add userspace interface to set PF_WAKE_UP_IDLE
sched_prefer_idle flag controls whether tasks can be woken to any
available idle cpu. It may be desirable to set sched_prefer_idle to 0
so that most tasks wake up to non-idle cpus under mostly_idle
threshold and have specialized tasks override this behavior through
other means. PF_WAKE_UP_IDLE flag per task provides exactly that. It
lets tasks with PF_WAKE_UP_IDLE flag set be woken up to any available
idle cpu independent of sched_prefer_idle flag setting. Currently
only kernel-space API exists to set PF_WAKE_UP_IDLE flag for a task.
This patch adds a user-space API (in /proc filesystem) to set
PF_WAKE_UP_IDLE flag for a given task. /proc/[pid]/sched_wake_up_idle
file can be written to set or clear PF_WAKE_UP_IDLE flag for a given
task.
Change-Id: I13a37e740195e503f457ebe291d54e83b230fbeb
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
[rameezmustafa@codeaurora.org: Port to msm-3.18]
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
[joonwoop@codeaurora.org: fixed minor conflict in kernel/sched/fair.c]
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/fair.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index cffeceec285c..4da8b618232e 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -83,7 +83,7 @@ unsigned int sysctl_sched_child_runs_first __read_mostly; /* * Controls whether, when SD_SHARE_PKG_RESOURCES is on, if all * tasks go to idle CPUs when woken. If this is off, note that the - * per-task flag PF_WAKE_ON_IDLE can still cause a task to go to an + * per-task flag PF_WAKE_UP_IDLE can still cause a task to go to an * idle CPU upon being woken. */ unsigned int __read_mostly sysctl_sched_wake_to_idle; @@ -2453,7 +2453,25 @@ static inline void update_cfs_shares(struct cfs_rq *cfs_rq) #endif /* CONFIG_FAIR_GROUP_SCHED */ #ifdef CONFIG_SMP -/* Precomputed fixed inverse multiplies for multiplication by y^n */ +u32 sched_get_wake_up_idle(struct task_struct *p) +{ + u32 enabled = p->flags & PF_WAKE_UP_IDLE; + + return !!enabled; +} + +int sched_set_wake_up_idle(struct task_struct *p, int wake_up_idle) +{ + int enable = !!wake_up_idle; + + if (enable) + p->flags |= PF_WAKE_UP_IDLE; + else + p->flags &= ~PF_WAKE_UP_IDLE; + + return 0; +} + static const u32 runnable_avg_yN_inv[] = { 0xffffffff, 0xfa83b2da, 0xf5257d14, 0xefe4b99a, 0xeac0c6e6, 0xe5b906e6, 0xe0ccdeeb, 0xdbfbb796, 0xd744fcc9, 0xd2a81d91, 0xce248c14, 0xc9b9bd85, |