From patchwork Sat Nov 7 08:44:56 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 7574971 X-Patchwork-Delegate: axboe@kernel.dk Return-Path: X-Original-To: patchwork-linux-block@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 078CBC05C6 for ; Sat, 7 Nov 2015 08:49:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 104D620783 for ; Sat, 7 Nov 2015 08:49:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D61C62077D for ; Sat, 7 Nov 2015 08:49:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751629AbbKGItg (ORCPT ); Sat, 7 Nov 2015 03:49:36 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:60614 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbbKGItg (ORCPT ); Sat, 7 Nov 2015 03:49:36 -0500 Received: from 213162068051.public.t-mobile.at ([213.162.68.51] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZuzBl-0004Xh-Tl; Sat, 07 Nov 2015 08:49:34 +0000 From: Christoph Hellwig To: Jens Axboe , Keith Busch Cc: Tejun Heo , Hannes Reinecke , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org Subject: [PATCH 02/12] block: defer timeouts to a workqueue Date: Sat, 7 Nov 2015 09:44:56 +0100 Message-Id: <1446885906-20967-3-git-send-email-hch@lst.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1446885906-20967-1-git-send-email-hch@lst.de> References: <1446885906-20967-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_BL_SPAMCOP_NET, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_WEB, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Timer context is not very useful for drivers to perform any meaningful abort action from. So instead of calling the driver from this useless context defer it to a workqueue as soon as possible. Note that while a delayed_work item would seem the right thing here I didn't dare to use it due to the magic in blk_add_timer that pokes deep into timer internals. But maybe this encourages Tejun to add a sensible API for that to the workqueue API and we'll all be fine in the end :) Signed-off-by: Christoph Hellwig --- block/blk-core.c | 8 ++++++++ block/blk-mq.c | 8 +++++--- block/blk-timeout.c | 5 +++-- block/blk.h | 2 +- include/linux/blkdev.h | 1 + 5 files changed, 18 insertions(+), 6 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index aecb544..2df634a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -664,6 +664,13 @@ static void blk_queue_usage_counter_release(struct percpu_ref *ref) wake_up_all(&q->mq_freeze_wq); } +static void blk_rq_timed_out_timer(unsigned long data) +{ + struct request_queue *q = (struct request_queue *)data; + + kblockd_schedule_work(&q->timeout_work); +} + struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) { struct request_queue *q; @@ -825,6 +832,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, if (blk_init_rl(&q->root_rl, q, GFP_KERNEL)) goto fail; + INIT_WORK(&q->timeout_work, blk_timeout_work); q->request_fn = rfn; q->prep_rq_fn = NULL; q->unprep_rq_fn = NULL; diff --git a/block/blk-mq.c b/block/blk-mq.c index c85c448..3a919ff 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -85,6 +85,7 @@ void blk_mq_freeze_queue_start(struct request_queue *q) freeze_depth = atomic_inc_return(&q->mq_freeze_depth); if (freeze_depth == 1) { percpu_ref_kill(&q->q_usage_counter); + cancel_work_sync(&q->timeout_work); blk_mq_run_hw_queues(q, false); } } @@ -617,9 +618,10 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, } } -static void blk_mq_rq_timer(unsigned long priv) +static void blk_mq_timeout_work(struct work_struct *work) { - struct request_queue *q = (struct request_queue *)priv; + struct request_queue *q = + container_of(work, struct request_queue, timeout_work); struct blk_mq_timeout_data data = { .next = 0, .next_set = 0, @@ -1978,7 +1980,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, hctxs[i]->queue_num = i; } - setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); + INIT_WORK(&q->timeout_work, blk_mq_timeout_work); blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); q->nr_queues = nr_cpu_ids; diff --git a/block/blk-timeout.c b/block/blk-timeout.c index aa40aa9..aedd128 100644 --- a/block/blk-timeout.c +++ b/block/blk-timeout.c @@ -127,9 +127,10 @@ static void blk_rq_check_expired(struct request *rq, unsigned long *next_timeout } } -void blk_rq_timed_out_timer(unsigned long data) +void blk_timeout_work(struct work_struct *work) { - struct request_queue *q = (struct request_queue *) data; + struct request_queue *q = + container_of(work, struct request_queue, timeout_work); unsigned long flags, next = 0; struct request *rq, *tmp; int next_set = 0; diff --git a/block/blk.h b/block/blk.h index 157c93d..f8d1784 100644 --- a/block/blk.h +++ b/block/blk.h @@ -95,7 +95,7 @@ static inline void blk_flush_integrity(void) } #endif -void blk_rq_timed_out_timer(unsigned long data); +void blk_timeout_work(struct work_struct *work); unsigned long blk_rq_timeout(unsigned long timeout); void blk_add_timer(struct request *req); void blk_delete_timer(struct request *); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index d045ca8..ed11b7a 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -407,6 +407,7 @@ struct request_queue { unsigned int rq_timeout; struct timer_list timeout; + struct work_struct timeout_work; struct list_head timeout_list; struct list_head icq_list;