From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753200AbaBQSOp (ORCPT ); Mon, 17 Feb 2014 13:14:45 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:24745 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750958AbaBQSOo (ORCPT ); Mon, 17 Feb 2014 13:14:44 -0500 X-IronPort-AV: E=Sophos;i="4.95,862,1384272000"; d="scan'208";a="9545760" From: Lai Jiangshan To: Tejun Heo Cc: Lai Jiangshan , linux-kernel@vger.kernel.org Subject: [PATCH 1/3] workqueue: free worker earlier in worker_thread() Date: Tue, 18 Feb 2014 00:24:01 +0800 Message-Id: <1392654243-2829-2-git-send-email-laijs@cn.fujitsu.com> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <1392654243-2829-1-git-send-email-laijs@cn.fujitsu.com> References: <1392472948-2486-1-git-send-email-laijs@cn.fujitsu.com> <1392654243-2829-1-git-send-email-laijs@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2014/02/18 00:22:09, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2014/02/18 00:22:11, Serialize complete at 2014/02/18 00:22:11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When @worker is set %WORKER_DIE, it is moved out from idle_list&idr, no one can access it excepct kthread_data(). And in worker_thread, its task is clearred %PF_WQ_WORKER, no one can access the @worker via kthread_data(), we can safely free it. Signed-off-by: Lai Jiangshan --- kernel/workqueue.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 783d5f2..fc05700 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1862,7 +1862,6 @@ static void destroy_worker(struct worker *worker) kthread_stop(worker->task); put_task_struct(worker->task); - kfree(worker); spin_lock_irq(&pool->lock); } @@ -2297,6 +2296,8 @@ woke_up: spin_unlock_irq(&pool->lock); WARN_ON_ONCE(!list_empty(&worker->entry)); worker->task->flags &= ~PF_WQ_WORKER; + /* No one can access to @worker now, free it. */ + kfree(worker); return 0; } -- 1.7.7.6