sched/fair: Simplify the code of should_we_balance()

We only consider group_balance_cpu() after there is no idle
cpu. So, just do comparison before return at these two cases.

Signed-off-by: Peng Wang <rocking@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/245c792f0e580b3ca342ad61257f4c066ee0f84f.1586594833.git.rocking@linux.alibaba.com
This commit is contained in:
Peng Wang 2020-04-11 17:20:20 +08:00 committed by Peter Zijlstra
parent ab93a4bc95
commit 64297f2b03
1 changed files with 5 additions and 11 deletions

View File

@ -9413,7 +9413,7 @@ static int active_load_balance_cpu_stop(void *data);
static int should_we_balance(struct lb_env *env)
{
struct sched_group *sg = env->sd->groups;
int cpu, balance_cpu = -1;
int cpu;
/*
* Ensure the balancing environment is consistent; can happen
@ -9434,18 +9434,12 @@ static int should_we_balance(struct lb_env *env)
if (!idle_cpu(cpu))
continue;
balance_cpu = cpu;
break;
/* Are we the first idle CPU? */
return cpu == env->dst_cpu;
}
if (balance_cpu == -1)
balance_cpu = group_balance_cpu(sg);
/*
* First idle CPU or the first CPU(busiest) in this sched group
* is eligible for doing load balancing at this and above domains.
*/
return balance_cpu == env->dst_cpu;
/* Are we the first CPU of this group ? */
return group_balance_cpu(sg) == env->dst_cpu;
}
/*