diff options
| author | Morten Rasmussen <[email protected]> | 2016-06-22 18:03:14 +0100 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2016-08-10 14:03:32 +0200 |
| commit | eaecf41f5abf80b63c8e025fcb9ee4aa203c3038 (patch) | |
| tree | 66828cd9474c5f77571323dbdf107568fc874fd1 | |
| parent | 772bd008cd9a1d4e8ce566f2edcc61d1c28fcbe5 (diff) | |
sched/fair: Optimize find_idlest_cpu() when there is no choice
In the current find_idlest_group()/find_idlest_cpu() search we end up
calling find_idlest_cpu() in a sched_group containing only one CPU in
the end. Checking idle-states becomes pointless when there is no
alternative, so bail out instead.
Signed-off-by: Morten Rasmussen <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | kernel/sched/fair.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d819da68857f..acdc351d2386 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5239,6 +5239,10 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu) int shallowest_idle_cpu = -1; int i; + /* Check if we have any choice: */ + if (group->group_weight == 1) + return cpumask_first(sched_group_cpus(group)); + /* Traverse only the allowed CPUs */ for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) { if (idle_cpu(i)) { |