From cfc03118047172f5bdc58d63c607d16d33ce5305 Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Tue, 23 Apr 2013 17:27:39 +0900 Subject: [PATCH] sched: Don't consider other cpus in our group in case of NEWLY_IDLE Commit 88b8dac0 makes load_balance() consider other cpus in its group, regardless of idle type. When we do NEWLY_IDLE balancing, we should not consider it, because a motivation of NEWLY_IDLE balancing is to turn this cpu to non idle state if needed. This is not the case of other cpus. So, change code not to consider other cpus for NEWLY_IDLE balancing. With this patch, assign 'if (pulled_task) this_rq->idle_stamp = 0' in idle_balance() is corrected, because NEWLY_IDLE balancing doesn't consider other cpus. Assigning to 'this_rq->idle_stamp' is now valid. Signed-off-by: Joonsoo Kim Tested-by: Jason Low Acked-by: Peter Zijlstra Cc: Srivatsa Vaddagiri Cc: Davidlohr Bueso Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1366705662-3587-4-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 726e129..dfa92b7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5026,8 +5026,21 @@ static int load_balance(int this_cpu, struct rq *this_rq, .cpus = cpus, }; + /* + * For NEWLY_IDLE load_balancing, we don't need to consider + * other cpus in our group + */ + if (idle == CPU_NEWLY_IDLE) { + env.dst_grpmask = NULL; + /* + * we don't care max_lb_iterations in this case, + * in following patch, this will be removed + */ + max_lb_iterations = 0; + } else + max_lb_iterations = cpumask_weight(env.dst_grpmask); + cpumask_copy(cpus, cpu_active_mask); - max_lb_iterations = cpumask_weight(env.dst_grpmask); schedstat_inc(sd, lb_count[idle]); -- 2.7.4