Commit-ID: 9659e1eeee28f7025b6545934d644d19e9c6e603 Gitweb: http://git.kernel.org/tip/9659e1eeee28f7025b6545934d644d19e9c6e603 Author: Xunlei Pang <[email protected]> AuthorDate: Mon, 19 Jan 2015 04:49:37 +0000 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 4 Feb 2015 07:52:29 +0100
sched/deadline: Remove cpu_active_mask from cpudl_find() cpu_active_mask is rarely changed (only on hotplug), so remove this operation to gain a little performance. If there is a change in cpu_active_mask, rq_online_dl() and rq_offline_dl() should take care of it normally, so cpudl::free_cpus carries enough information for us. For the rare case when a task is put onto a dying cpu (which rq_offline_dl() can't handle in a timely fashion), it will be handled through _cpu_down()->...->multi_cpu_stop()->migration_call() ->migrate_tasks(), preventing the task from hanging on the dead cpu. Cc: Juri Lelli <[email protected]> Signed-off-by: Xunlei Pang <[email protected]> [peterz: changelog] Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Cc: Linus Torvalds <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/sched/cpudeadline.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index fd9d3fb..c6acb07 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -108,8 +108,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, const struct sched_dl_entity *dl_se = &p->dl; if (later_mask && - cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed) && - cpumask_and(later_mask, later_mask, cpu_active_mask)) { + cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) { best_cpu = cpumask_any(later_mask); goto out; } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) && -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
