From 16b269436b7213ebc01dcfcc9dafa8535b676ccb Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Mon, 19 Jan 2015 04:49:36 +0000 Subject: [PATCH] sched/deadline: Modify cpudl::free_cpus to reflect rd->online Currently, cpudl::free_cpus contains all CPUs during init, see cpudl_init(). When calling cpudl_find(), we have to add rd->span to avoid selecting the cpu outside the current root domain, because cpus_allowed cannot be depended on when performing clustered scheduling using the cpuset, see find_later_rq(). This patch adds cpudl_set_freecpu() and cpudl_clear_freecpu() for changing cpudl::free_cpus when doing rq_online_dl()/rq_offline_dl(), so we can avoid the rd->span operation when calling cpudl_find() in find_later_rq(). Signed-off-by: Xunlei Pang Signed-off-by: Peter Zijlstra (Intel) Cc: Juri Lelli Cc: Linus Torvalds Link: http://lkml.kernel.org/r/1421642980-10045-1-git-send-email-pang.xunlei@linaro.org Signed-off-by: Ingo Molnar --- kernel/sched/cpudeadline.c | 28 ++++++++++++++++++++++++---- kernel/sched/cpudeadline.h | 2 ++ kernel/sched/deadline.c | 5 ++--- 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index 539ca3ce071b..fd9d3fb49d0d 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -107,7 +107,9 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, int best_cpu = -1; const struct sched_dl_entity *dl_se = &p->dl; - if (later_mask && cpumask_and(later_mask, later_mask, cp->free_cpus)) { + if (later_mask && + cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed) && + cpumask_and(later_mask, later_mask, cpu_active_mask)) { best_cpu = cpumask_any(later_mask); goto out; } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) && @@ -185,6 +187,26 @@ out: raw_spin_unlock_irqrestore(&cp->lock, flags); } +/* + * cpudl_set_freecpu - Set the cpudl.free_cpus + * @cp: the cpudl max-heap context + * @cpu: rd attached cpu + */ +void cpudl_set_freecpu(struct cpudl *cp, int cpu) +{ + cpumask_set_cpu(cpu, cp->free_cpus); +} + +/* + * cpudl_clear_freecpu - Clear the cpudl.free_cpus + * @cp: the cpudl max-heap context + * @cpu: rd attached cpu + */ +void cpudl_clear_freecpu(struct cpudl *cp, int cpu) +{ + cpumask_clear_cpu(cpu, cp->free_cpus); +} + /* * cpudl_init - initialize the cpudl structure * @cp: the cpudl max-heap context @@ -203,7 +225,7 @@ int cpudl_init(struct cpudl *cp) if (!cp->elements) return -ENOMEM; - if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) { + if (!zalloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) { kfree(cp->elements); return -ENOMEM; } @@ -211,8 +233,6 @@ int cpudl_init(struct cpudl *cp) for_each_possible_cpu(i) cp->elements[i].idx = IDX_INVALID; - cpumask_setall(cp->free_cpus); - return 0; } diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h index 020039bd1326..1a0a6ef2fbe1 100644 --- a/kernel/sched/cpudeadline.h +++ b/kernel/sched/cpudeadline.h @@ -24,6 +24,8 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, struct cpumask *later_mask); void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid); int cpudl_init(struct cpudl *cp); +void cpudl_set_freecpu(struct cpudl *cp, int cpu); +void cpudl_clear_freecpu(struct cpudl *cp, int cpu); void cpudl_cleanup(struct cpudl *cp); #endif /* CONFIG_SMP */ diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index b52092f2636d..e7b272233c5c 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1165,9 +1165,6 @@ static int find_later_rq(struct task_struct *task) * We have to consider system topology and task affinity * first, then we can look for a suitable cpu. */ - cpumask_copy(later_mask, task_rq(task)->rd->span); - cpumask_and(later_mask, later_mask, cpu_active_mask); - cpumask_and(later_mask, later_mask, &task->cpus_allowed); best_cpu = cpudl_find(&task_rq(task)->rd->cpudl, task, later_mask); if (best_cpu == -1) @@ -1562,6 +1559,7 @@ static void rq_online_dl(struct rq *rq) if (rq->dl.overloaded) dl_set_overload(rq); + cpudl_set_freecpu(&rq->rd->cpudl, rq->cpu); if (rq->dl.dl_nr_running > 0) cpudl_set(&rq->rd->cpudl, rq->cpu, rq->dl.earliest_dl.curr, 1); } @@ -1573,6 +1571,7 @@ static void rq_offline_dl(struct rq *rq) dl_clear_overload(rq); cpudl_set(&rq->rd->cpudl, rq->cpu, 0, 0); + cpudl_clear_freecpu(&rq->rd->cpudl, rq->cpu); } void init_sched_dl_class(void) -- 2.34.1