diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched.c | 33 | ||||
| -rw-r--r-- | kernel/sched_fair.c | 4 |
2 files changed, 28 insertions, 9 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 7f827b70ae02..cfa695819252 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -169,8 +169,6 @@ struct task_group { /* runqueue "owned" by this group on each cpu */ struct cfs_rq **cfs_rq; unsigned long shares; - /* spinlock to serialize modification to shares */ - spinlock_t lock; struct rcu_head rcu; }; @@ -182,6 +180,11 @@ static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp; static struct sched_entity *init_sched_entity_p[NR_CPUS]; static struct cfs_rq *init_cfs_rq_p[NR_CPUS]; +/* task_group_mutex serializes add/remove of task groups and also changes to + * a task group's cpu shares. + */ +static DEFINE_MUTEX(task_group_mutex); + /* Default task group. * Every task in system belong to this group at bootup. */ @@ -221,9 +224,21 @@ static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) p->se.parent = task_group(p)->se[cpu]; } +static inline void lock_task_group_list(void) +{ + mutex_lock(&task_group_mutex); +} + +static inline void unlock_task_group_list(void) +{ + mutex_unlock(&task_group_mutex); +} + #else static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { } +static inline void lock_task_group_list(void) { } +static inline void unlock_task_group_list(void) { } #endif /* CONFIG_FAIR_GROUP_SCHED */ @@ -6768,7 +6783,6 @@ void __init sched_init(void) se->parent = NULL; } init_task_group.shares = init_task_group_load; - spin_lock_init(&init_task_group.lock); #endif for (j = 0; j < CPU_LOAD_IDX_MAX; j++) @@ -7008,14 +7022,15 @@ struct task_group *sched_create_group(void) se->parent = NULL; } + tg->shares = NICE_0_LOAD; + + lock_task_group_list(); for_each_possible_cpu(i) { rq = cpu_rq(i); cfs_rq = tg->cfs_rq[i]; list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); } - - tg->shares = NICE_0_LOAD; - spin_lock_init(&tg->lock); + unlock_task_group_list(); return tg; @@ -7061,10 +7076,12 @@ void sched_destroy_group(struct task_group *tg) struct cfs_rq *cfs_rq = NULL; int i; + lock_task_group_list(); for_each_possible_cpu(i) { cfs_rq = tg->cfs_rq[i]; list_del_rcu(&cfs_rq->leaf_cfs_rq_list); } + unlock_task_group_list(); BUG_ON(!cfs_rq); @@ -7146,7 +7163,7 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares) if (shares < 2) shares = 2; - spin_lock(&tg->lock); + lock_task_group_list(); if (tg->shares == shares) goto done; @@ -7155,7 +7172,7 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares) set_se_shares(tg->se[i], shares); done: - spin_unlock(&tg->lock); + unlock_task_group_list(); return 0; } diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index da7c061e7206..0c5fdce67228 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -690,7 +690,7 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) /* Iterate thr' all leaf cfs_rq's on a runqueue */ #define for_each_leaf_cfs_rq(rq, cfs_rq) \ - list_for_each_entry(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) + list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) /* Do the two (enqueued) entities belong to the same group ? */ static inline int @@ -1132,7 +1132,9 @@ static void print_cfs_stats(struct seq_file *m, int cpu) #ifdef CONFIG_FAIR_GROUP_SCHED print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs); #endif + lock_task_group_list(); for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq) print_cfs_rq(m, cpu, cfs_rq); + unlock_task_group_list(); } #endif |