From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB5C2C433E0 for ; Mon, 15 Jun 2020 06:12:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2DE3206DB for ; Mon, 15 Jun 2020 06:12:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728224AbgFOGMu (ORCPT ); Mon, 15 Jun 2020 02:12:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:49922 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728163AbgFOGMu (ORCPT ); Mon, 15 Jun 2020 02:12:50 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 7AA0AAE65; Mon, 15 Jun 2020 06:12:52 +0000 (UTC) Subject: Re: [PATCH 3/4] bcache: use delayed kworker fo asynchronous devices registration To: colyli@suse.de, axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org References: <20200614165333.124999-1-colyli@suse.de> <20200614165333.124999-4-colyli@suse.de> From: Hannes Reinecke Message-ID: <9bd21fc5-2666-e239-3da1-dc51c3ca2e49@suse.de> Date: Mon, 15 Jun 2020 08:12:46 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200614165333.124999-4-colyli@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-bcache-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bcache@vger.kernel.org Message-ID: <20200615061246.rzLcDlLvTGR6ZKtQD18DT5lCXENA54EI4613QTPnkvc@z> On 6/14/20 6:53 PM, colyli@suse.de wrote: > From: Coly Li > > This patch changes the asynchronous registration kworker to a delayed > kworker. There is probability queue_work() queues the async registration > kworker to the same CPU (even though very little), then the process > which writing sysfs interface to reigster bcache device may won't return > immeidately. queue_delayed_work() in this patch will delay 10 jiffies > before insert the kworker to run queue, which makes sure the registering > process may always returns to user space in time. > > Fixes: 9e23ccf8f0a22 ("bcache: asynchronous devices registration") > Signed-off-by: Coly Li > Cc: Hannes Reinecke > --- > drivers/md/bcache/super.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > Reviewed-by: Hannes Reinecke Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer