Patch "sched/fair: add triggers for OPP change requests" introduced OPP
change triggers for enqueue_task_fair(), but the trigger was operating only
for wakeups. Fact is that it makes sense to consider wakeup_new also (i.e.,
fork()), as we don't know anything about a newly created task and thus we
most certainly want to jump to max OPP to not harm performance too much.
However, it is not currently possible (or at least it wasn't evident to me
how to do so :/) to tell new wakeups from other (non wakeup) operations.
This patch introduces an additional flag in sched.h that is only set at
fork() time and it is then consumed in enqueue_task_fair() for our purpose.
cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Steve Muckle <smuckle@linaro.org>
#endif
rq = __task_rq_lock(p);
#endif
rq = __task_rq_lock(p);
- activate_task(rq, p, 0);
+ activate_task(rq, p, ENQUEUE_WAKEUP_NEW);
p->on_rq = TASK_ON_RQ_QUEUED;
trace_sched_wakeup_new(p);
check_preempt_curr(rq, p, WF_FORK);
p->on_rq = TASK_ON_RQ_QUEUED;
trace_sched_wakeup_new(p);
check_preempt_curr(rq, p, WF_FORK);
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
- int task_new = !(flags & ENQUEUE_WAKEUP);
+ int task_new = flags & ENQUEUE_WAKEUP_NEW;
+ int task_wakeup = flags & ENQUEUE_WAKEUP;
for_each_sched_entity(se) {
if (se->on_rq)
for_each_sched_entity(se) {
if (se->on_rq)
* because we get here also during load balancing, but
* in these cases it seems wise to trigger as single
* request after load balancing is done.
* because we get here also during load balancing, but
* in these cases it seems wise to trigger as single
* request after load balancing is done.
- *
- * XXX: how about fork()? Do we need a special
- * flag/something to tell if we are here after a
- * fork() (wakeup_task_new)?
+ if (task_new || task_wakeup)
update_capacity_of(cpu_of(rq));
}
hrtick_update(rq);
update_capacity_of(cpu_of(rq));
}
hrtick_update(rq);
#endif
#define ENQUEUE_REPLENISH 0x08
#define ENQUEUE_RESTORE 0x10
#endif
#define ENQUEUE_REPLENISH 0x08
#define ENQUEUE_RESTORE 0x10
+#define ENQUEUE_WAKEUP_NEW 0x20
#define DEQUEUE_SLEEP 0x01
#define DEQUEUE_SAVE 0x02
#define DEQUEUE_SLEEP 0x01
#define DEQUEUE_SAVE 0x02