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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 37EB8C04AB2 for ; Thu, 9 May 2019 18:52:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DBBB204FD for ; Thu, 9 May 2019 18:52:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557427957; bh=QzCzpG7nqtzDp/K2VGk2Dc3YCAeq6d3p0u/YucM0gio=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0tHiEwRD6b2eEiM5bR1RC7eet748cPh3q9JZYS7Viu2OJurYVFCR0JCndTk8D/Z05 xZsDFuqVhVaqGEvicKbadJUuGnSS9h3VxNxJbwNwg1vDLVu+uiQbVJKrhGlu1WjWwP HE0qjbK6D/cu3l0DNa/z0qTE9qY/pnMAxwUkdP2g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728744AbfEISwf (ORCPT ); Thu, 9 May 2019 14:52:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:46700 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728733AbfEISwe (ORCPT ); Thu, 9 May 2019 14:52:34 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4FF0A2177E; Thu, 9 May 2019 18:52:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557427953; bh=QzCzpG7nqtzDp/K2VGk2Dc3YCAeq6d3p0u/YucM0gio=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iX3G8Lt6BxkS0x7YyRtPwp5i7SVWpfqUSP3ClzNMkMeSk3v8GQYQodOSrVzPdoWfK 6q62MEVbAxMiOpzrtzq9eARqSgmNO3IwC7ruP45dJjvn3l02pna7fI3/jrCWDXG3Mu HJ3F05moBAQ9HafEoSV78HyiZ8R69cgtzU8nediE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sagi Grimberg , Bart Van Assche , James Smart , linux-nvme@lists.infradead.org, Keith Busch , Christoph Hellwig , Ming Lei , Jens Axboe , Sasha Levin Subject: [PATCH 5.0 65/95] blk-mq: introduce blk_mq_complete_request_sync() Date: Thu, 9 May 2019 20:42:22 +0200 Message-Id: <20190509181314.017487714@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190509181309.180685671@linuxfoundation.org> References: <20190509181309.180685671@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 1b8f21b74c3c9c82fce5a751d7aefb7cc0b8d33d ] In NVMe's error handler, follows the typical steps of tearing down hardware for recovering controller: 1) stop blk_mq hw queues 2) stop the real hw queues 3) cancel in-flight requests via blk_mq_tagset_busy_iter(tags, cancel_request, ...) cancel_request(): mark the request as abort blk_mq_complete_request(req); 4) destroy real hw queues However, there may be race between #3 and #4, because blk_mq_complete_request() may run q->mq_ops->complete(rq) remotelly and asynchronously, and ->complete(rq) may be run after #4. This patch introduces blk_mq_complete_request_sync() for fixing the above race. Cc: Sagi Grimberg Cc: Bart Van Assche Cc: James Smart Cc: linux-nvme@lists.infradead.org Reviewed-by: Keith Busch Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-mq.c | 7 +++++++ include/linux/blk-mq.h | 1 + 2 files changed, 8 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 5a2585d69c817..6930c82ab75fc 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -657,6 +657,13 @@ bool blk_mq_complete_request(struct request *rq) } EXPORT_SYMBOL(blk_mq_complete_request); +void blk_mq_complete_request_sync(struct request *rq) +{ + WRITE_ONCE(rq->state, MQ_RQ_COMPLETE); + rq->q->mq_ops->complete(rq); +} +EXPORT_SYMBOL_GPL(blk_mq_complete_request_sync); + int blk_mq_request_started(struct request *rq) { return blk_mq_rq_state(rq) != MQ_RQ_IDLE; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 0e030f5f76b66..7e092bdac27f6 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -306,6 +306,7 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, void blk_mq_kick_requeue_list(struct request_queue *q); void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); bool blk_mq_complete_request(struct request *rq); +void blk_mq_complete_request_sync(struct request *rq); bool blk_mq_bio_list_merge(struct request_queue *q, struct list_head *list, struct bio *bio); bool blk_mq_queue_stopped(struct request_queue *q); -- 2.20.1