From f147f29eb7c4959e5f8be604ce2d23979c86378c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 1 Apr 2013 11:23:35 -0700 Subject: [PATCH] workqueue: break init_and_link_pwq() into two functions and introduce alloc_unbound_pwq() Break init_and_link_pwq() into init_pwq() and link_pwq() and move unbound-workqueue specific handling into apply_workqueue_attrs(). Also, factor out unbound pool and pool_workqueue allocation into alloc_unbound_pwq(). This reorganization is to prepare for NUMA affinity and doesn't introduce any functional changes. Signed-off-by: Tejun Heo Reviewed-by: Lai Jiangshan --- kernel/workqueue.c | 78 +++++++++++++++++++++++++++++----------------- 1 file changed, 49 insertions(+), 29 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 170226a24da8..c8d047b6c895 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -3626,13 +3626,10 @@ static void pwq_adjust_max_active(struct pool_workqueue *pwq) spin_unlock_irq(&pwq->pool->lock); } -static void init_and_link_pwq(struct pool_workqueue *pwq, - struct workqueue_struct *wq, - struct worker_pool *pool, - struct pool_workqueue **p_last_pwq) +/* initialize newly zalloced @pwq which is associated with @wq and @pool */ +static void init_pwq(struct pool_workqueue *pwq, struct workqueue_struct *wq, + struct worker_pool *pool) { - int node; - BUG_ON((unsigned long)pwq & WORK_STRUCT_FLAG_MASK); pwq->pool = pool; @@ -3642,8 +3639,15 @@ static void init_and_link_pwq(struct pool_workqueue *pwq, INIT_LIST_HEAD(&pwq->delayed_works); INIT_LIST_HEAD(&pwq->mayday_node); INIT_WORK(&pwq->unbound_release_work, pwq_unbound_release_workfn); +} - mutex_lock(&wq->mutex); +/* sync @pwq with the current state of its associated wq and link it */ +static void link_pwq(struct pool_workqueue *pwq, + struct pool_workqueue **p_last_pwq) +{ + struct workqueue_struct *wq = pwq->wq; + + lockdep_assert_held(&wq->mutex); /* * Set the matching work_color. This is synchronized with @@ -3658,14 +3662,29 @@ static void init_and_link_pwq(struct pool_workqueue *pwq, /* link in @pwq */ list_add_rcu(&pwq->pwqs_node, &wq->pwqs); +} - if (wq->flags & WQ_UNBOUND) { - copy_workqueue_attrs(wq->unbound_attrs, pool->attrs); - for_each_node(node) - rcu_assign_pointer(wq->numa_pwq_tbl[node], pwq); +/* obtain a pool matching @attr and create a pwq associating the pool and @wq */ +static struct pool_workqueue *alloc_unbound_pwq(struct workqueue_struct *wq, + const struct workqueue_attrs *attrs) +{ + struct worker_pool *pool; + struct pool_workqueue *pwq; + + lockdep_assert_held(&wq_pool_mutex); + + pool = get_unbound_pool(attrs); + if (!pool) + return NULL; + + pwq = kmem_cache_zalloc(pwq_cache, GFP_KERNEL); + if (!pwq) { + put_unbound_pool(pool); + return NULL; } - mutex_unlock(&wq->mutex); + init_pwq(pwq, wq, pool); + return pwq; } /** @@ -3686,9 +3705,8 @@ int apply_workqueue_attrs(struct workqueue_struct *wq, const struct workqueue_attrs *attrs) { struct workqueue_attrs *new_attrs; - struct pool_workqueue *pwq = NULL, *last_pwq; - struct worker_pool *pool; - int ret; + struct pool_workqueue *pwq, *last_pwq; + int node, ret; /* only unbound workqueues can change attributes */ if (WARN_ON(!(wq->flags & WQ_UNBOUND))) @@ -3707,22 +3725,21 @@ int apply_workqueue_attrs(struct workqueue_struct *wq, cpumask_and(new_attrs->cpumask, new_attrs->cpumask, cpu_possible_mask); mutex_lock(&wq_pool_mutex); - - pwq = kmem_cache_zalloc(pwq_cache, GFP_KERNEL); - if (!pwq) { - mutex_unlock(&wq_pool_mutex); + pwq = alloc_unbound_pwq(wq, new_attrs); + mutex_unlock(&wq_pool_mutex); + if (!pwq) goto enomem; - } - pool = get_unbound_pool(new_attrs); - if (!pool) { - mutex_unlock(&wq_pool_mutex); - goto enomem; - } + mutex_lock(&wq->mutex); - mutex_unlock(&wq_pool_mutex); + link_pwq(pwq, &last_pwq); + + copy_workqueue_attrs(wq->unbound_attrs, new_attrs); + for_each_node(node) + rcu_assign_pointer(wq->numa_pwq_tbl[node], pwq); + + mutex_unlock(&wq->mutex); - init_and_link_pwq(pwq, wq, pool, &last_pwq); if (last_pwq) { spin_lock_irq(&last_pwq->pool->lock); put_pwq(last_pwq); @@ -3736,7 +3753,6 @@ out_free: return ret; enomem: - kmem_cache_free(pwq_cache, pwq); ret = -ENOMEM; goto out_free; } @@ -3757,7 +3773,11 @@ static int alloc_and_link_pwqs(struct workqueue_struct *wq) struct worker_pool *cpu_pools = per_cpu(cpu_worker_pools, cpu); - init_and_link_pwq(pwq, wq, &cpu_pools[highpri], NULL); + init_pwq(pwq, wq, &cpu_pools[highpri]); + + mutex_lock(&wq->mutex); + link_pwq(pwq, NULL); + mutex_unlock(&wq->mutex); } return 0; } else { -- 2.34.1