From patchwork Mon Dec 4 10:42:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Valente X-Patchwork-Id: 10089971 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 044B060327 for ; Mon, 4 Dec 2017 10:42:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B5BEF26E54 for ; Mon, 4 Dec 2017 10:42:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AA59128BE6; Mon, 4 Dec 2017 10:42:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI, URIBL_DBL_ABUSE_SPAM autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D1F226E54 for ; Mon, 4 Dec 2017 10:42:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752129AbdLDKmM (ORCPT ); Mon, 4 Dec 2017 05:42:12 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:46573 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753463AbdLDKmL (ORCPT ); Mon, 4 Dec 2017 05:42:11 -0500 Received: by mail-wm0-f66.google.com with SMTP id r78so4895893wme.5 for ; Mon, 04 Dec 2017 02:42:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=IIJV6/CpZoqnHosKw+SQFI0XPAfm6/f4QMeImGCIGOg=; b=ifCul4rjA2YZKvLr5xMZbE7SeiHqDVUCN4UROmGiwGVcF7NtHc50KjStIJKjtew8Oz jNemj8WLCUD8sNJdcskYhXdI+I0jRlgmGCRjcrWKXijWe34OP9bwJhdu8z13+/djm3pf zF9Do+bLhwkpbDYvA134vT047OgMyG1uHY89E= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=IIJV6/CpZoqnHosKw+SQFI0XPAfm6/f4QMeImGCIGOg=; b=bn5fcmlx6ZSnb+zEcxw8fIna+eCLkBYhEVfT1003cBng4vm2JYahIIevH1KL58zp0N CaWAMxj/aBv9rgimK0vP9alLrzJ1omnb5kJReiizABAWiYVde1l2vlUg5NhwnrrmlToa NAHPslcaohq7MQV08YsV/5kfy6aQL2Gj+8D+RUanGLnSXHEB8qlK7v0GosUqKig2HTT0 gQLmYzo9XJmi5P0s3VRfP12m5al7ji7RUBUGyTyLVkPNHWZa5ND0xfDUfyYjyMg1yINV aep1+a5pw+/t0PXVLxemqxjqo4lbsHXAUPFesCWUBsQ4uCzslLt5E/MhawFufzo39B69 OHPA== X-Gm-Message-State: AKGB3mJD8rkswkBxTguf0E/Xegtb30Ig6h2Z+tcVEKwWlJ7P9qUdGsmm b2vT9ReAcxXAUp6Y3eVeiIC2+w== X-Google-Smtp-Source: AGs4zMY45/hz85fZn/WrUQ05I/8RF/YWZnLuF8hgM22+29e8lbT+hYiFj/DCBHYRm8FYLX9EZFrN5w== X-Received: by 10.28.129.77 with SMTP id c74mr2742574wmd.124.1512384130080; Mon, 04 Dec 2017 02:42:10 -0800 (PST) Received: from wifi-122_dhcprange-87.wifi.unimo.it ([155.185.122.87]) by smtp.gmail.com with ESMTPSA id w46sm11962562wrb.86.2017.12.04.02.42.08 (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 04 Dec 2017 02:42:08 -0800 (PST) From: Paolo Valente To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, ulf.hansson@linaro.org, broonie@kernel.org, linus.walleij@linaro.org, lucmiccio@gmail.com, Paolo Valente Subject: [PATCH V2] block, bfq: remove batches of confusing ifdefs Date: Mon, 4 Dec 2017 11:42:05 +0100 Message-Id: <20171204104205.3290-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.10.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit a33801e8b473 ("block, bfq: move debug blkio stats behind CONFIG_DEBUG_BLK_CGROUP") introduced two batches of confusing ifdefs: one reported in [1], plus a similar one in another function. This commit removes both batches, in the way suggested in [1]. [1] https://www.spinics.net/lists/linux-block/msg20043.html Fixes: a33801e8b473 ("block, bfq: move debug blkio stats behind CONFIG_DEBUG_BLK_CGROUP") Reported-by: Linus Torvalds Tested-by: Luca Miccio Signed-off-by: Paolo Valente --- block/bfq-iosched.c | 127 +++++++++++++++++++++++++++++----------------------- 1 file changed, 72 insertions(+), 55 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index bcb6d21..3feed64 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -3689,35 +3689,16 @@ static struct request *__bfq_dispatch_request(struct blk_mq_hw_ctx *hctx) return rq; } -static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx) -{ - struct bfq_data *bfqd = hctx->queue->elevator->elevator_data; - struct request *rq; #if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) - struct bfq_queue *in_serv_queue, *bfqq; - bool waiting_rq, idle_timer_disabled; -#endif - - spin_lock_irq(&bfqd->lock); - -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) - in_serv_queue = bfqd->in_service_queue; - waiting_rq = in_serv_queue && bfq_bfqq_wait_request(in_serv_queue); - - rq = __bfq_dispatch_request(hctx); - - idle_timer_disabled = - waiting_rq && !bfq_bfqq_wait_request(in_serv_queue); - -#else - rq = __bfq_dispatch_request(hctx); -#endif - spin_unlock_irq(&bfqd->lock); +static void bfq_update_dispatch_stats(struct request_queue *q, + struct request *rq, + struct bfq_queue *in_serv_queue, + bool idle_timer_disabled) +{ + struct bfq_queue *bfqq = rq ? RQ_BFQQ(rq) : NULL; -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) - bfqq = rq ? RQ_BFQQ(rq) : NULL; if (!idle_timer_disabled && !bfqq) - return rq; + return; /* * rq and bfqq are guaranteed to exist until this function @@ -3732,7 +3713,7 @@ static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx) * In addition, the following queue lock guarantees that * bfqq_group(bfqq) exists as well. */ - spin_lock_irq(hctx->queue->queue_lock); + spin_lock_irq(q->queue_lock); if (idle_timer_disabled) /* * Since the idle timer has been disabled, @@ -3751,9 +3732,37 @@ static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx) bfqg_stats_set_start_empty_time(bfqg); bfqg_stats_update_io_remove(bfqg, rq->cmd_flags); } - spin_unlock_irq(hctx->queue->queue_lock); + spin_unlock_irq(q->queue_lock); +} +#else +static inline void bfq_update_dispatch_stats(struct request_queue *q, + struct request *rq, + struct bfq_queue *in_serv_queue, + bool idle_timer_disabled) {} #endif +static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx) +{ + struct bfq_data *bfqd = hctx->queue->elevator->elevator_data; + struct request *rq; + struct bfq_queue *in_serv_queue; + bool waiting_rq, idle_timer_disabled; + + spin_lock_irq(&bfqd->lock); + + in_serv_queue = bfqd->in_service_queue; + waiting_rq = in_serv_queue && bfq_bfqq_wait_request(in_serv_queue); + + rq = __bfq_dispatch_request(hctx); + + idle_timer_disabled = + waiting_rq && !bfq_bfqq_wait_request(in_serv_queue); + + spin_unlock_irq(&bfqd->lock); + + bfq_update_dispatch_stats(hctx->queue, rq, in_serv_queue, + idle_timer_disabled); + return rq; } @@ -4276,16 +4285,46 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq) return idle_timer_disabled; } +#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) +static void bfq_update_insert_stats(struct request_queue *q, + struct bfq_queue *bfqq, + bool idle_timer_disabled, + unsigned int cmd_flags) +{ + if (!bfqq) + return; + + /* + * bfqq still exists, because it can disappear only after + * either it is merged with another queue, or the process it + * is associated with exits. But both actions must be taken by + * the same process currently executing this flow of + * instructions. + * + * In addition, the following queue lock guarantees that + * bfqq_group(bfqq) exists as well. + */ + spin_lock_irq(q->queue_lock); + bfqg_stats_update_io_add(bfqq_group(bfqq), bfqq, cmd_flags); + if (idle_timer_disabled) + bfqg_stats_update_idle_time(bfqq_group(bfqq)); + spin_unlock_irq(q->queue_lock); +} +#else +static inline void bfq_update_insert_stats(struct request_queue *q, + struct bfq_queue *bfqq, + bool idle_timer_disabled, + unsigned int cmd_flags) {} +#endif + static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, bool at_head) { struct request_queue *q = hctx->queue; struct bfq_data *bfqd = q->elevator->elevator_data; -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) struct bfq_queue *bfqq = RQ_BFQQ(rq); bool idle_timer_disabled = false; unsigned int cmd_flags; -#endif spin_lock_irq(&bfqd->lock); if (blk_mq_sched_try_insert_merge(q, rq)) { @@ -4304,7 +4343,6 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, else list_add_tail(&rq->queuelist, &bfqd->dispatch); } else { -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) idle_timer_disabled = __bfq_insert_request(bfqd, rq); /* * Update bfqq, because, if a queue merge has occurred @@ -4312,9 +4350,6 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, * redirected into a new queue. */ bfqq = RQ_BFQQ(rq); -#else - __bfq_insert_request(bfqd, rq); -#endif if (rq_mergeable(rq)) { elv_rqhash_add(q, rq); @@ -4323,35 +4358,17 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, } } -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) /* * Cache cmd_flags before releasing scheduler lock, because rq * may disappear afterwards (for example, because of a request * merge). */ cmd_flags = rq->cmd_flags; -#endif + spin_unlock_irq(&bfqd->lock); -#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) - if (!bfqq) - return; - /* - * bfqq still exists, because it can disappear only after - * either it is merged with another queue, or the process it - * is associated with exits. But both actions must be taken by - * the same process currently executing this flow of - * instruction. - * - * In addition, the following queue lock guarantees that - * bfqq_group(bfqq) exists as well. - */ - spin_lock_irq(q->queue_lock); - bfqg_stats_update_io_add(bfqq_group(bfqq), bfqq, cmd_flags); - if (idle_timer_disabled) - bfqg_stats_update_idle_time(bfqq_group(bfqq)); - spin_unlock_irq(q->queue_lock); -#endif + bfq_update_insert_stats(q, bfqq, idle_timer_disabled, + cmd_flags); } static void bfq_insert_requests(struct blk_mq_hw_ctx *hctx,