workqueue: Convert to state machine callbacks
Get rid of the prio ordering of the separate notifiers and use a proper state
callback pair.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153335.197083890@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index e1c0e99..c9dd5fb 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4611,84 +4611,65 @@
pool->attrs->cpumask) < 0);
}
-/*
- * Workqueues should be brought up before normal priority CPU notifiers.
- * This will be registered high priority CPU notifier.
- */
-static int workqueue_cpu_up_callback(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
+int workqueue_prepare_cpu(unsigned int cpu)
{
- int cpu = (unsigned long)hcpu;
+ struct worker_pool *pool;
+
+ for_each_cpu_worker_pool(pool, cpu) {
+ if (pool->nr_workers)
+ continue;
+ if (!create_worker(pool))
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+int workqueue_online_cpu(unsigned int cpu)
+{
struct worker_pool *pool;
struct workqueue_struct *wq;
int pi;
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_UP_PREPARE:
- for_each_cpu_worker_pool(pool, cpu) {
- if (pool->nr_workers)
- continue;
- if (!create_worker(pool))
- return NOTIFY_BAD;
- }
- break;
+ mutex_lock(&wq_pool_mutex);
- case CPU_DOWN_FAILED:
- case CPU_ONLINE:
- mutex_lock(&wq_pool_mutex);
+ for_each_pool(pool, pi) {
+ mutex_lock(&pool->attach_mutex);
- for_each_pool(pool, pi) {
- mutex_lock(&pool->attach_mutex);
+ if (pool->cpu == cpu)
+ rebind_workers(pool);
+ else if (pool->cpu < 0)
+ restore_unbound_workers_cpumask(pool, cpu);
- if (pool->cpu == cpu)
- rebind_workers(pool);
- else if (pool->cpu < 0)
- restore_unbound_workers_cpumask(pool, cpu);
-
- mutex_unlock(&pool->attach_mutex);
- }
-
- /* update NUMA affinity of unbound workqueues */
- list_for_each_entry(wq, &workqueues, list)
- wq_update_unbound_numa(wq, cpu, true);
-
- mutex_unlock(&wq_pool_mutex);
- break;
+ mutex_unlock(&pool->attach_mutex);
}
- return NOTIFY_OK;
+
+ /* update NUMA affinity of unbound workqueues */
+ list_for_each_entry(wq, &workqueues, list)
+ wq_update_unbound_numa(wq, cpu, true);
+
+ mutex_unlock(&wq_pool_mutex);
+ return 0;
}
-/*
- * Workqueues should be brought down after normal priority CPU notifiers.
- * This will be registered as low priority CPU notifier.
- */
-static int workqueue_cpu_down_callback(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
+int workqueue_offline_cpu(unsigned int cpu)
{
- int cpu = (unsigned long)hcpu;
struct work_struct unbind_work;
struct workqueue_struct *wq;
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_DOWN_PREPARE:
- /* unbinding per-cpu workers should happen on the local CPU */
- INIT_WORK_ONSTACK(&unbind_work, wq_unbind_fn);
- queue_work_on(cpu, system_highpri_wq, &unbind_work);
+ /* unbinding per-cpu workers should happen on the local CPU */
+ INIT_WORK_ONSTACK(&unbind_work, wq_unbind_fn);
+ queue_work_on(cpu, system_highpri_wq, &unbind_work);
- /* update NUMA affinity of unbound workqueues */
- mutex_lock(&wq_pool_mutex);
- list_for_each_entry(wq, &workqueues, list)
- wq_update_unbound_numa(wq, cpu, false);
- mutex_unlock(&wq_pool_mutex);
+ /* update NUMA affinity of unbound workqueues */
+ mutex_lock(&wq_pool_mutex);
+ list_for_each_entry(wq, &workqueues, list)
+ wq_update_unbound_numa(wq, cpu, false);
+ mutex_unlock(&wq_pool_mutex);
- /* wait for per-cpu unbinding to finish */
- flush_work(&unbind_work);
- destroy_work_on_stack(&unbind_work);
- break;
- }
- return NOTIFY_OK;
+ /* wait for per-cpu unbinding to finish */
+ flush_work(&unbind_work);
+ destroy_work_on_stack(&unbind_work);
+ return 0;
}
#ifdef CONFIG_SMP
@@ -5490,9 +5471,6 @@
pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);
- cpu_notifier(workqueue_cpu_up_callback, CPU_PRI_WORKQUEUE_UP);
- hotcpu_notifier(workqueue_cpu_down_callback, CPU_PRI_WORKQUEUE_DOWN);
-
wq_numa_init();
/* initialize CPU pools */