Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754540AbYGVKXp (ORCPT ); Tue, 22 Jul 2008 06:23:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752232AbYGVKXi (ORCPT ); Tue, 22 Jul 2008 06:23:38 -0400 Received: from x346.tv-sign.ru ([89.108.83.215]:32814 "EHLO mail.screens.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751820AbYGVKXh (ORCPT ); Tue, 22 Jul 2008 06:23:37 -0400 Date: Tue, 22 Jul 2008 14:27:17 +0400 From: Oleg Nesterov To: Akinobu Mita Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCH] workqueues: do CPU_UP_CANCELED if CPU_UP_PREPARE fails Message-ID: <20080722102717.GB1068@tv-sign.ru> References: <200807220826.m6M8Q4I6018588@imap1.linux-foundation.org> <20080722084526.GA165@tv-sign.ru> <20080722085938.GA5857@localhost.localdomain> <20080722091636.GA241@tv-sign.ru> <20080722095539.GA6188@localhost.localdomain> <20080722102354.GA1068@tv-sign.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080722102354.GA1068@tv-sign.ru> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2016 Lines: 63 (replaces workqueue-proper-error-unwinding-in-cpu-hotplug-error-path.patch) The bug was pointed out by Akinobu Mita , and this patch is based on his original patch. workqueue_cpu_callback(CPU_UP_PREPARE) expects that if it returns NOTIFY_BAD, _cpu_up() will send CPU_UP_CANCELED then. However, this is not true since "cpu hotplug: cpu: deliver CPU_UP_CANCELED only to NOTIFY_OKed callbacks with CPU_UP_PREPARE" commit: a0d8cdb652d35af9319a9e0fb7134de2a276c636 The callback which has returned NOTIFY_BAD will not receive CPU_UP_CANCELED. Change the code to fulfil the CPU_UP_CANCELED logic if CPU_UP_PREPARE fails. Signed-off-by: Oleg Nesterov --- 26-rc2/kernel/workqueue.c~WQ_CPU_UP_PREPARE 2008-07-12 19:40:57.000000000 +0400 +++ 26-rc2/kernel/workqueue.c 2008-07-22 13:43:47.000000000 +0400 @@ -911,6 +911,7 @@ static int __devinit workqueue_cpu_callb unsigned int cpu = (unsigned long)hcpu; struct cpu_workqueue_struct *cwq; struct workqueue_struct *wq; + int ret = NOTIFY_OK; action &= ~CPU_TASKS_FROZEN; @@ -918,7 +919,7 @@ static int __devinit workqueue_cpu_callb case CPU_UP_PREPARE: cpu_set(cpu, cpu_populated_map); } - +undo: list_for_each_entry(wq, &workqueues, list) { cwq = per_cpu_ptr(wq->cpu_wq, cpu); @@ -928,7 +929,9 @@ static int __devinit workqueue_cpu_callb break; printk(KERN_ERR "workqueue [%s] for %i failed\n", wq->name, cpu); - return NOTIFY_BAD; + action = CPU_UP_CANCELED; + ret = NOTIFY_BAD; + goto undo; case CPU_ONLINE: start_workqueue_thread(cwq, cpu); @@ -948,7 +951,7 @@ static int __devinit workqueue_cpu_callb cpu_clear(cpu, cpu_populated_map); } - return NOTIFY_OK; + return ret; } void __init init_workqueues(void) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/