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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 6B331C742A5 for ; Fri, 12 Jul 2019 02:48:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D8D8214AF for ; Fri, 12 Jul 2019 02:48:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729242AbfGLCsO (ORCPT ); Thu, 11 Jul 2019 22:48:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55374 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728743AbfGLCsO (ORCPT ); Thu, 11 Jul 2019 22:48:14 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4E694C049589; Fri, 12 Jul 2019 02:48:14 +0000 (UTC) Received: from localhost (ovpn-8-19.pek2.redhat.com [10.72.8.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6D79219C67; Fri, 12 Jul 2019 02:48:13 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, "James E . J . Bottomley" , "Martin K . Petersen" , linux-scsi@vger.kernel.org, Ming Lei , Bart Van Assche , Hannes Reinecke , Christoph Hellwig , Thomas Gleixner , Keith Busch Subject: [RFC PATCH 7/7] blk-mq: handle requests dispatched from IO scheduler in case that hctx is dead Date: Fri, 12 Jul 2019 10:47:26 +0800 Message-Id: <20190712024726.1227-8-ming.lei@redhat.com> In-Reply-To: <20190712024726.1227-1-ming.lei@redhat.com> References: <20190712024726.1227-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Fri, 12 Jul 2019 02:48:14 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org If hctx becomes dead, all in-queue IO requests aimed at this hctx have to be re-submitted, so cover requests queued in scheduler queue. Cc: Bart Van Assche Cc: Hannes Reinecke Cc: Christoph Hellwig Cc: Thomas Gleixner Cc: Keith Busch Signed-off-by: Ming Lei --- block/blk-mq.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index e4588d30840c..3ad1944a8e70 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2298,6 +2298,7 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) enum hctx_type type; bool hctx_dead; struct request *rq; + struct elevator_queue *e; hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); ctx = __blk_mq_get_ctx(hctx->queue, cpu); @@ -2309,12 +2310,31 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) hctx_dead = cpumask_first_and(hctx->cpumask, cpu_online_mask) >= nr_cpu_ids; - spin_lock(&ctx->lock); - if (!list_empty(&ctx->rq_lists[type])) { - list_splice_init(&ctx->rq_lists[type], &tmp); - blk_mq_hctx_clear_pending(hctx, ctx); + e = hctx->queue->elevator; + if (!e) { + spin_lock(&ctx->lock); + if (!list_empty(&ctx->rq_lists[type])) { + list_splice_init(&ctx->rq_lists[type], &tmp); + blk_mq_hctx_clear_pending(hctx, ctx); + } + spin_unlock(&ctx->lock); + } else if (hctx_dead) { + LIST_HEAD(sched_tmp); + + while ((rq = e->type->ops.dispatch_request(hctx))) { + if (rq->mq_hctx != hctx) + list_add(&rq->queuelist, &sched_tmp); + else + list_add(&rq->queuelist, &tmp); + } + + while (!list_empty(&sched_tmp)) { + rq = list_entry(sched_tmp.next, struct request, + queuelist); + list_del_init(&rq->queuelist); + blk_mq_sched_insert_request(rq, true, true, true); + } } - spin_unlock(&ctx->lock); if (list_empty(&tmp)) return 0; -- 2.20.1