From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754062AbeDPIe5 (ORCPT ); Mon, 16 Apr 2018 04:34:57 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:42404 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754006AbeDPIez (ORCPT ); Mon, 16 Apr 2018 04:34:55 -0400 Subject: Re: [PATCH] blk-mq: mark hctx RESTART when get budget fails To: Ming Lei Cc: axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <1523865336-17326-1-git-send-email-jianchao.w.wang@oracle.com> <20180416081503.GB23664@ming.t460p> From: "jianchao.wang" Message-ID: <11e10ccf-bdeb-4790-3bec-e3f49ab246c8@oracle.com> Date: Mon, 16 Apr 2018 16:34:43 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180416081503.GB23664@ming.t460p> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8864 signatures=668698 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1804160079 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ming Thanks for your kindly response. On 04/16/2018 04:15 PM, Ming Lei wrote: >> - if (!blk_mq_get_dispatch_budget(hctx)) >> + if (!blk_mq_get_dispatch_budget(hctx)) { >> + blk_mq_sched_mark_restart_hctx(hctx); > The RESTART flag still may not take into effect if all requests are > completed before calling blk_mq_sched_mark_restart_hctx(). > Yes, this is indeed a very tricky scenario. Sincerely Jianchao