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sched: Fix SD_POWERSAVING_BALANCE|SD_PREFER_LOCAL vs SD_WAKE_AFFINE

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The SD_POWERSAVING_BALANCE|SD_PREFER_LOCAL code can break out of
the domain iteration early, making us miss the SD_WAKE_AFFINE bits.

Fix this by continuing iteration until there is no need for a
larger domain.

This also cleans up the cgroup stuff a bit, but not having two
update_shares() invocations.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-09-17 09:01:14 +02:00 committed by Ingo Molnar
parent de69a80be3
commit 29cd8bae39
1 changed files with 27 additions and 15 deletions
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42
kernel/sched_fair.c
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@ -1333,11 +1333,12 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
*/
static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
{
struct sched_domain *tmp, *shares = NULL, *sd = NULL;
struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
int cpu = smp_processor_id();
int prev_cpu = task_cpu(p);
int new_cpu = cpu;
int want_affine = 0;
int want_sd = 1;
int sync = wake_flags & WF_SYNC;
if (sd_flag & SD_BALANCE_WAKE) {
@ -1369,33 +1370,44 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
nr_running /= 2;
if (nr_running < capacity)
break;
want_sd = 0;
}
if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
if (sched_feat(LB_SHARES_UPDATE)) {
update_shares(tmp);
shares = tmp;
}
if (wake_affine(tmp, p, sync)) {
new_cpu = cpu;
goto out;
}
affine_sd = tmp;
want_affine = 0;
}
if (!want_sd && !want_affine)
break;
if (!(tmp->flags & sd_flag))
continue;
sd = tmp;
if (want_sd)
sd = tmp;
}
if (sd && sd != shares && sched_feat(LB_SHARES_UPDATE))
update_shares(sd);
if (sched_feat(LB_SHARES_UPDATE)) {
/*
* Pick the largest domain to update shares over
*/
tmp = sd;
if (affine_sd && (!tmp ||
cpumask_weight(sched_domain_span(affine_sd)) >
cpumask_weight(sched_domain_span(sd))))
tmp = affine_sd;
if (tmp)
update_shares(tmp);
}
if (affine_sd && wake_affine(affine_sd, p, sync)) {
new_cpu = cpu;
goto out;
}
while (sd) {
int load_idx = sd->forkexec_idx;