manager_mutex is only used to protect the attaching for the pool and the pool->workers list. It protects the pool->workers and operations based on this list, such as: cpu-binding for the workers in the pool->workers the operations to set/clear WORKER_UNBOUND
So we can simply rename manager_mutex to attach_mutex without any functionality changed. Signed-off-by: Lai Jiangshan <la...@cn.fujitsu.com> --- kernel/workqueue.c | 44 +++++++++++++++++++++--------------------- kernel/workqueue_internal.h | 4 +- 2 files changed, 24 insertions(+), 24 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 4ae6a3c..728b515 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -65,7 +65,7 @@ enum { * be executing on any CPU. The pool behaves as an unbound one. * * Note that DISASSOCIATED should be flipped only while holding - * manager_mutex to avoid changing binding state while + * attach_mutex to avoid changing binding state while * create_worker() is in progress. */ POOL_DISASSOCIATED = 1 << 2, /* cpu can't serve workers */ @@ -122,7 +122,7 @@ enum { * cpu or grabbing pool->lock is enough for read access. If * POOL_DISASSOCIATED is set, it's identical to L. * - * M: pool->manager_mutex protected. + * A: pool->attach_mutex protected. * * PL: wq_pool_mutex protected. * @@ -160,8 +160,8 @@ struct worker_pool { /* see manage_workers() for details on the two manager mutexes */ struct mutex manager_arb; /* manager arbitration */ - struct mutex manager_mutex; /* manager exclusion */ - struct list_head workers; /* M: attached workers */ + struct mutex attach_mutex; /* attach/detach exclusion */ + struct list_head workers; /* A: attached workers */ struct completion *detach_completion; /* all workers detached */ struct ida worker_ida; /* worker IDs for task name */ @@ -367,14 +367,14 @@ static void copy_workqueue_attrs(struct workqueue_attrs *to, * @worker: iteration cursor * @pool: worker_pool to iterate workers of * - * This must be called with @pool->manager_mutex. + * This must be called with @pool->attach_mutex. * * The if/else clause exists only for the lockdep assertion and can be * ignored. */ #define for_each_pool_worker(worker, pool) \ list_for_each_entry((worker), &(pool)->workers, node) \ - if (({ lockdep_assert_held(&pool->manager_mutex); false; })) { } \ + if (({ lockdep_assert_held(&pool->attach_mutex); false; })) { } \ else /** @@ -1696,11 +1696,11 @@ static void worker_detach_from_pool(struct worker *worker, { struct completion *detach_completion = NULL; - mutex_lock(&pool->manager_mutex); + mutex_lock(&pool->attach_mutex); list_del(&worker->node); if (list_empty(&pool->workers)) detach_completion = pool->detach_completion; - mutex_unlock(&pool->manager_mutex); + mutex_unlock(&pool->attach_mutex); if (detach_completion) complete(detach_completion); @@ -1753,7 +1753,7 @@ static struct worker *create_worker(struct worker_pool *pool) /* prevent userland from meddling with cpumask of workqueue workers */ worker->task->flags |= PF_NO_SETAFFINITY; - mutex_lock(&pool->manager_mutex); + mutex_lock(&pool->attach_mutex); /* * set_cpus_allowed_ptr() will fail if the cpumask doesn't have any @@ -1762,7 +1762,7 @@ static struct worker *create_worker(struct worker_pool *pool) set_cpus_allowed_ptr(worker->task, pool->attrs->cpumask); /* - * The pool->manager_mutex ensures %POOL_DISASSOCIATED + * The pool->attach_mutex ensures %POOL_DISASSOCIATED * remains stable across this function. See the comments above the * flag definition for details. */ @@ -1772,7 +1772,7 @@ static struct worker *create_worker(struct worker_pool *pool) /* successful, attach the worker to the pool */ list_add_tail(&worker->node, &pool->workers); - mutex_unlock(&pool->manager_mutex); + mutex_unlock(&pool->attach_mutex); return worker; @@ -3456,7 +3456,7 @@ static int init_worker_pool(struct worker_pool *pool) (unsigned long)pool); mutex_init(&pool->manager_arb); - mutex_init(&pool->manager_mutex); + mutex_init(&pool->attach_mutex); INIT_LIST_HEAD(&pool->workers); ida_init(&pool->worker_ida); @@ -3513,7 +3513,7 @@ static void put_unbound_pool(struct worker_pool *pool) /* * Become the manager and destroy all workers. Grabbing * manager_arb prevents @pool's workers from blocking on - * manager_mutex. + * attach_mutex. */ mutex_lock(&pool->manager_arb); @@ -3523,10 +3523,10 @@ static void put_unbound_pool(struct worker_pool *pool) WARN_ON(pool->nr_workers || pool->nr_idle); spin_unlock_irq(&pool->lock); - mutex_lock(&pool->manager_mutex); + mutex_lock(&pool->attach_mutex); if (!list_empty(&pool->workers)) pool->detach_completion = &detach_completion; - mutex_unlock(&pool->manager_mutex); + mutex_unlock(&pool->attach_mutex); if (pool->detach_completion) wait_for_completion(pool->detach_completion); @@ -4513,11 +4513,11 @@ static void wq_unbind_fn(struct work_struct *work) for_each_cpu_worker_pool(pool, cpu) { WARN_ON_ONCE(cpu != smp_processor_id()); - mutex_lock(&pool->manager_mutex); + mutex_lock(&pool->attach_mutex); spin_lock_irq(&pool->lock); /* - * We've blocked all manager operations. Make all workers + * We've blocked all attach/detach operations. Make all workers * unbound and set DISASSOCIATED. Before this, all workers * except for the ones which are still executing works from * before the last CPU down must be on the cpu. After @@ -4529,7 +4529,7 @@ static void wq_unbind_fn(struct work_struct *work) pool->flags |= POOL_DISASSOCIATED; spin_unlock_irq(&pool->lock); - mutex_unlock(&pool->manager_mutex); + mutex_unlock(&pool->attach_mutex); /* * Call schedule() so that we cross rq->lock and thus can @@ -4570,7 +4570,7 @@ static void rebind_workers(struct worker_pool *pool) { struct worker *worker; - lockdep_assert_held(&pool->manager_mutex); + lockdep_assert_held(&pool->attach_mutex); /* * Restore CPU affinity of all workers. As all idle workers should @@ -4638,7 +4638,7 @@ static void restore_unbound_workers_cpumask(struct worker_pool *pool, int cpu) static cpumask_t cpumask; struct worker *worker; - lockdep_assert_held(&pool->manager_mutex); + lockdep_assert_held(&pool->attach_mutex); /* is @cpu allowed for @pool? */ if (!cpumask_test_cpu(cpu, pool->attrs->cpumask)) @@ -4683,7 +4683,7 @@ static int workqueue_cpu_up_callback(struct notifier_block *nfb, mutex_lock(&wq_pool_mutex); for_each_pool(pool, pi) { - mutex_lock(&pool->manager_mutex); + mutex_lock(&pool->attach_mutex); if (pool->cpu == cpu) { spin_lock_irq(&pool->lock); @@ -4695,7 +4695,7 @@ static int workqueue_cpu_up_callback(struct notifier_block *nfb, restore_unbound_workers_cpumask(pool, cpu); } - mutex_unlock(&pool->manager_mutex); + mutex_unlock(&pool->attach_mutex); } /* update NUMA affinity of unbound workqueues */ diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h index 8888e06..4521587 100644 --- a/kernel/workqueue_internal.h +++ b/kernel/workqueue_internal.h @@ -37,8 +37,8 @@ struct worker { struct task_struct *task; /* I: worker task */ struct worker_pool *pool; /* I: the associated pool */ /* L: for rescuers */ - struct list_head node; /* M: anchored at pool->workers */ - /* M: runs through worker->node */ + struct list_head node; /* A: anchored at pool->workers */ + /* A: runs through worker->node */ unsigned long last_active; /* L: last active timestamp */ unsigned int flags; /* X: flags */ -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/