diff options
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 66bd7ff23f1..799d23b4e35 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -305,6 +305,7 @@ struct rq { }; static DEFINE_PER_CPU(struct rq, runqueues) ____cacheline_aligned_in_smp; +static DEFINE_MUTEX(sched_hotcpu_mutex); static inline int cpu_of(struct rq *rq) { @@ -4520,13 +4521,13 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) struct task_struct *p; int retval; - lock_cpu_hotplug(); + mutex_lock(&sched_hotcpu_mutex); read_lock(&tasklist_lock); p = find_process_by_pid(pid); if (!p) { read_unlock(&tasklist_lock); - unlock_cpu_hotplug(); + mutex_unlock(&sched_hotcpu_mutex); return -ESRCH; } @@ -4553,7 +4554,7 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) out_unlock: put_task_struct(p); - unlock_cpu_hotplug(); + mutex_unlock(&sched_hotcpu_mutex); return retval; } @@ -4610,7 +4611,7 @@ long sched_getaffinity(pid_t pid, cpumask_t *mask) struct task_struct *p; int retval; - lock_cpu_hotplug(); + mutex_lock(&sched_hotcpu_mutex); read_lock(&tasklist_lock); retval = -ESRCH; @@ -4626,7 +4627,7 @@ long sched_getaffinity(pid_t pid, cpumask_t *mask) out_unlock: read_unlock(&tasklist_lock); - unlock_cpu_hotplug(); + mutex_unlock(&sched_hotcpu_mutex); if (retval) return retval; @@ -5388,7 +5389,12 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) struct rq *rq; switch (action) { + case CPU_LOCK_ACQUIRE: + mutex_lock(&sched_hotcpu_mutex); + break; + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: p = kthread_create(migration_thread, hcpu, "migration/%d",cpu); if (IS_ERR(p)) return NOTIFY_BAD; @@ -5402,12 +5408,14 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) break; case CPU_ONLINE: + case CPU_ONLINE_FROZEN: /* Strictly unneccessary, as first user will wake it. */ wake_up_process(cpu_rq(cpu)->migration_thread); break; #ifdef CONFIG_HOTPLUG_CPU case CPU_UP_CANCELED: + case CPU_UP_CANCELED_FROZEN: if (!cpu_rq(cpu)->migration_thread) break; /* Unbind it from offline cpu so it can run. Fall thru. */ @@ -5418,6 +5426,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) break; case CPU_DEAD: + case CPU_DEAD_FROZEN: migrate_live_tasks(cpu); rq = cpu_rq(cpu); kthread_stop(rq->migration_thread); @@ -5433,7 +5442,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) BUG_ON(rq->nr_running != 0); /* No need to migrate the tasks: it was best-effort if - * they didn't do lock_cpu_hotplug(). Just wake up + * they didn't take sched_hotcpu_mutex. Just wake up * the requestors. */ spin_lock_irq(&rq->lock); while (!list_empty(&rq->migration_queue)) { @@ -5447,6 +5456,9 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) spin_unlock_irq(&rq->lock); break; #endif + case CPU_LOCK_RELEASE: + mutex_unlock(&sched_hotcpu_mutex); + break; } return NOTIFY_OK; } @@ -6822,10 +6834,10 @@ int arch_reinit_sched_domains(void) { int err; - lock_cpu_hotplug(); + mutex_lock(&sched_hotcpu_mutex); detach_destroy_domains(&cpu_online_map); err = arch_init_sched_domains(&cpu_online_map); - unlock_cpu_hotplug(); + mutex_unlock(&sched_hotcpu_mutex); return err; } @@ -6904,14 +6916,20 @@ static int update_sched_domains(struct notifier_block *nfb, { switch (action) { case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: case CPU_DOWN_PREPARE: + case CPU_DOWN_PREPARE_FROZEN: detach_destroy_domains(&cpu_online_map); return NOTIFY_OK; case CPU_UP_CANCELED: + case CPU_UP_CANCELED_FROZEN: case CPU_DOWN_FAILED: + case CPU_DOWN_FAILED_FROZEN: case CPU_ONLINE: + case CPU_ONLINE_FROZEN: case CPU_DEAD: + case CPU_DEAD_FROZEN: /* * Fall through and re-initialise the domains. */ @@ -6930,12 +6948,12 @@ void __init sched_init_smp(void) { cpumask_t non_isolated_cpus; - lock_cpu_hotplug(); + mutex_lock(&sched_hotcpu_mutex); arch_init_sched_domains(&cpu_online_map); cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map); if (cpus_empty(non_isolated_cpus)) cpu_set(smp_processor_id(), non_isolated_cpus); - unlock_cpu_hotplug(); + mutex_unlock(&sched_hotcpu_mutex); /* XXX: Theoretical race here - CPU may be hotplugged now */ hotcpu_notifier(update_sched_domains, 0); |