From patchwork Mon Sep 19 07:09:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 12979717 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 143F2C54EE9 for ; Mon, 19 Sep 2022 06:58:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229561AbiISG6r (ORCPT ); Mon, 19 Sep 2022 02:58:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229879AbiISG6c (ORCPT ); Mon, 19 Sep 2022 02:58:32 -0400 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21C4C1D0FC; Sun, 18 Sep 2022 23:58:28 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4MWFp54Ck3z6SCDK; Mon, 19 Sep 2022 14:56:29 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.127.227]) by APP2 (Coremail) with SMTP id Syh0CgAnenMPEyhjBBpFBA--.10045S5; Mon, 19 Sep 2022 14:58:26 +0800 (CST) From: Yu Kuai To: paolo.valente@linaro.org, axboe@kernel.dk Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com Subject: [PATCH v2 1/3] wbt: don't show valid wbt_lat_usec in sysfs while wbt is disabled Date: Mon, 19 Sep 2022 15:09:14 +0800 Message-Id: <20220919070916.2738443-2-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220919070916.2738443-1-yukuai1@huaweicloud.com> References: <20220919070916.2738443-1-yukuai1@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: Syh0CgAnenMPEyhjBBpFBA--.10045S5 X-Coremail-Antispam: 1UD129KBjvJXoWxWw4fArykuFW5tr1rGw17ZFb_yoW5GFWfpa y7Ga4akF12gF4UWFyxJr4Duw43Kw48KrWxK3y8G3yYvrya9r129a1vkFW8XF95ZFWxCFsx Wrn0yrZ8uF4jgaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9m14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r1I6r4UM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCF04k20xvY0x0EwIxGrwCFx2 IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v2 6r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67 AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IY s7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr 0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUqAp5UUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Yu Kuai Currently, if wbt is initialized and then disabled by wbt_disable_default(), sysfs will still show valid wbt_lat_usec, which will confuse users that wbt is still enabled. This patch shows wbt_lat_usec as zero and forbid to set it while wbt is disabled. Signed-off-by: Yu Kuai Reported-and-tested-by: Holger Hoffstätte --- block/blk-sysfs.c | 9 ++++++++- block/blk-wbt.c | 7 +++++++ block/blk-wbt.h | 5 +++++ 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index e1f009aba6fd..1955bb6a284d 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -467,10 +467,14 @@ static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) { + u64 lat; + if (!wbt_rq_qos(q)) return -EINVAL; - return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); + lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000); + + return sprintf(page, "%llu\n", lat); } static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, @@ -493,6 +497,9 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, return ret; } + if (wbt_disabled(q)) + return -EINVAL; + if (val == -1) val = wbt_default_latency_nsec(q); else if (val >= 0) diff --git a/block/blk-wbt.c b/block/blk-wbt.c index a9982000b667..68851c2c02d2 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -422,6 +422,13 @@ static void wbt_update_limits(struct rq_wb *rwb) rwb_wake_all(rwb); } +bool wbt_disabled(struct request_queue *q) +{ + struct rq_qos *rqos = wbt_rq_qos(q); + + return !rqos || RQWB(rqos)->enable_state == WBT_STATE_OFF_DEFAULT; +} + u64 wbt_get_min_lat(struct request_queue *q) { struct rq_qos *rqos = wbt_rq_qos(q); diff --git a/block/blk-wbt.h b/block/blk-wbt.h index 7e44eccc676d..e42465ddcbb6 100644 --- a/block/blk-wbt.h +++ b/block/blk-wbt.h @@ -94,6 +94,7 @@ void wbt_enable_default(struct request_queue *); u64 wbt_get_min_lat(struct request_queue *q); void wbt_set_min_lat(struct request_queue *q, u64 val); +bool wbt_disabled(struct request_queue *); void wbt_set_write_cache(struct request_queue *, bool); @@ -125,6 +126,10 @@ static inline u64 wbt_default_latency_nsec(struct request_queue *q) { return 0; } +static inline bool wbt_disabled(struct request_queue *q) +{ + return true; +} #endif /* CONFIG_BLK_WBT */