workqueue: rename manager_mutex to attach_mutex

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 let's rename manager_mutex to attach_mutex to better reflect its
role. This patch is a pure rename.

tj: Minor command and description updates.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 22 insertions, 22 deletions

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index d6b31ff60c52..38b9ea7c204c 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 */