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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-06-03 15:41:20 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-08-02 14:26:07 +0200 |
| commit | e709715915d69b6a929d77e7652c9c3fea61c317 (patch) | |
| tree | 69ed9845b4b4c412cc17d59469e46ebb41de0c31 /kernel/sched.c | |
| parent | a5004278f0525dcb9aa43703ef77bf371ea837cd (diff) | |
| download | lwn-e709715915d69b6a929d77e7652c9c3fea61c317.tar.gz lwn-e709715915d69b6a929d77e7652c9c3fea61c317.zip | |
sched: Optimize unused cgroup configuration
When cgroup group scheduling is built in, skip some code paths
if we don't have any (but the root) cgroups configured.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 26976cd8be0f..ca1f76ba7773 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1629,8 +1629,14 @@ static int tg_load_down(struct task_group *tg, void *data) static void update_shares(struct sched_domain *sd) { - u64 now = cpu_clock(raw_smp_processor_id()); - s64 elapsed = now - sd->last_update; + s64 elapsed; + u64 now; + + if (root_task_group_empty()) + return; + + now = cpu_clock(raw_smp_processor_id()); + elapsed = now - sd->last_update; if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) { sd->last_update = now; @@ -1640,6 +1646,9 @@ static void update_shares(struct sched_domain *sd) static void update_shares_locked(struct rq *rq, struct sched_domain *sd) { + if (root_task_group_empty()) + return; + spin_unlock(&rq->lock); update_shares(sd); spin_lock(&rq->lock); @@ -1647,6 +1656,9 @@ static void update_shares_locked(struct rq *rq, struct sched_domain *sd) static void update_h_load(long cpu) { + if (root_task_group_empty()) + return; + walk_tg_tree(tg_load_down, tg_nop, (void *)cpu); } |