From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752976AbaETJnH (ORCPT ); Tue, 20 May 2014 05:43:07 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:39921 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752930AbaETJnE (ORCPT ); Tue, 20 May 2014 05:43:04 -0400 X-IronPort-AV: E=Sophos;i="4.98,873,1392134400"; d="scan'208";a="30762586" From: Lai Jiangshan To: CC: Tejun Heo , Lai Jiangshan Subject: [PATCH V3 06/10] workqueue: convert worker_idr to worker_ida Date: Tue, 20 May 2014 17:46:32 +0800 Message-ID: <1400579204-3647-7-git-send-email-laijs@cn.fujitsu.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1400579204-3647-1-git-send-email-laijs@cn.fujitsu.com> References: <1399877792-13046-1-git-send-email-laijs@cn.fujitsu.com> <1400579204-3647-1-git-send-email-laijs@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.167.226.103] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We don't need to iterate workers via worker_idr, worker_idr is used for allocating/freeing ID only, so we convert it to worker_ida. By using ida_simple_get/remove(), worker_ida can be protected by itself, so we don't need manager_mutex to protect it and the ID-removal code is allowed to be moved out from worker_detach_from_pool(). And in later patch, worker_detach_from_pool() will be used in rescuers which doesn't have IDs, so we directly move the ID-removal code out from worker_detach_from_pool(). Signed-off-by: Lai Jiangshan --- kernel/workqueue.c | 20 ++++++++------------ 1 files changed, 8 insertions(+), 12 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index fd2f265..637c244 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -161,10 +161,11 @@ 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 idr worker_idr; /* M: worker IDs */ struct list_head workers; /* M: attached workers */ struct completion *detach_completion; /* all workers detached */ + struct ida worker_ida; /* worker IDs for task name */ + struct workqueue_attrs *attrs; /* I: worker attributes */ struct hlist_node hash_node; /* PL: unbound_pool_hash node */ int refcnt; /* PL: refcnt for unbound pools */ @@ -1696,7 +1697,6 @@ static void worker_detach_from_pool(struct worker *worker, struct completion *detach_completion = NULL; mutex_lock(&pool->manager_mutex); - idr_remove(&pool->worker_idr, worker->id); list_del(&worker->node); if (list_empty(&pool->workers)) detach_completion = pool->detach_completion; @@ -1727,11 +1727,8 @@ static struct worker *create_worker(struct worker_pool *pool) lockdep_assert_held(&pool->manager_mutex); - /* - * ID is needed to determine kthread name. Allocate ID first - * without installing the pointer. - */ - id = idr_alloc(&pool->worker_idr, NULL, 0, 0, GFP_KERNEL); + /* ID is needed to determine kthread name. */ + id = ida_simple_get(&pool->worker_ida, 0, 0, GFP_KERNEL); if (id < 0) goto fail; @@ -1772,8 +1769,6 @@ static struct worker *create_worker(struct worker_pool *pool) if (pool->flags & POOL_DISASSOCIATED) worker->flags |= WORKER_UNBOUND; - /* successful, commit the pointer to idr */ - idr_replace(&pool->worker_idr, worker, worker->id); /* successful, attach the worker to the pool */ list_add_tail(&worker->node, &pool->workers); @@ -1781,7 +1776,7 @@ static struct worker *create_worker(struct worker_pool *pool) fail: if (id >= 0) - idr_remove(&pool->worker_idr, id); + ida_simple_remove(&pool->worker_ida, id); kfree(worker); return NULL; } @@ -2250,6 +2245,7 @@ woke_up: worker->task->flags &= ~PF_WQ_WORKER; set_task_comm(worker->task, "kworker/dying"); + ida_simple_remove(&pool->worker_ida, worker->id); worker_detach_from_pool(worker, pool); kfree(worker); return 0; @@ -3486,9 +3482,9 @@ static int init_worker_pool(struct worker_pool *pool) mutex_init(&pool->manager_arb); mutex_init(&pool->manager_mutex); - idr_init(&pool->worker_idr); INIT_LIST_HEAD(&pool->workers); + ida_init(&pool->worker_ida); INIT_HLIST_NODE(&pool->hash_node); pool->refcnt = 1; @@ -3503,7 +3499,7 @@ static void rcu_free_pool(struct rcu_head *rcu) { struct worker_pool *pool = container_of(rcu, struct worker_pool, rcu); - idr_destroy(&pool->worker_idr); + ida_destroy(&pool->worker_ida); free_workqueue_attrs(pool->attrs); kfree(pool); } -- 1.7.4.4