From nobody Mon Apr 6 13:31:52 2026 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 2A636C433F5 for ; Fri, 30 Sep 2022 02:57:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230062AbiI3C50 (ORCPT ); Thu, 29 Sep 2022 22:57:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229715AbiI3C5K (ORCPT ); Thu, 29 Sep 2022 22:57:10 -0400 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B901104627; Thu, 29 Sep 2022 19:57:08 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4MdvwP2MSyz6SCKp; Fri, 30 Sep 2022 10:55:01 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.127.227]) by APP2 (Coremail) with SMTP id Syh0CgAnenP_WjZjTFJvBg--.12213S8; Fri, 30 Sep 2022 10:57:06 +0800 (CST) From: Yu Kuai To: jack@suse.cz, hch@infradead.org, ebiggers@kernel.org, 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 v4 4/6] blk-wbt: don't show valid wbt_lat_usec in sysfs while wbt is disabled Date: Fri, 30 Sep 2022 11:19:04 +0800 Message-Id: <20220930031906.4164306-5-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220930031906.4164306-1-yukuai1@huaweicloud.com> References: <20220930031906.4164306-1-yukuai1@huaweicloud.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: Syh0CgAnenP_WjZjTFJvBg--.12213S8 X-Coremail-Antispam: 1UD129KBjvJXoW7trWxZw1ruw4fWFWkGryxuFg_yoW5Jr4xpa y7GFyakF42gF48XFyxJF4DW3yakw10kFW7GrWxG3yYyF1Y9r12va1vkFW8XF95ZFWxCFsx Xrn0yrZ8Cr4jg3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPY14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r 4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQSdkU UUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 if it's disabled. Signed-off-by: Yu Kuai Reported-and-tested-by: Holger Hoffst=C3=A4tte Reviewed-by: Christoph Hellwig --- block/blk-sysfs.c | 6 +++++- block/blk-wbt.c | 8 ++++++++ block/blk-wbt.h | 5 +++++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index e71b3b43927c..5a6950b4ff69 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, =20 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) { + u64 lat; + if (!wbt_rq_qos(q)) return -EINVAL; =20 - return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); + lat =3D wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000); + + return sprintf(page, "%llu\n", lat); } =20 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *pag= e, diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 9cac54569ff1..1852ef223c68 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -422,6 +422,14 @@ static void wbt_update_limits(struct rq_wb *rwb) rwb_wake_all(rwb); } =20 +bool wbt_disabled(struct request_queue *q) +{ + struct rq_qos *rqos =3D wbt_rq_qos(q); + + return !rqos || RQWB(rqos)->enable_state =3D=3D WBT_STATE_OFF_DEFAULT || + RQWB(rqos)->enable_state =3D=3D WBT_STATE_OFF_MANUAL; +} + u64 wbt_get_min_lat(struct request_queue *q) { struct rq_qos *rqos =3D wbt_rq_qos(q); diff --git a/block/blk-wbt.h b/block/blk-wbt.h index 7fe98638fff5..e3ea6e7e2900 100644 --- a/block/blk-wbt.h +++ b/block/blk-wbt.h @@ -96,6 +96,7 @@ void wbt_enable_default(struct request_queue *); =20 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 *); =20 void wbt_set_write_cache(struct request_queue *, bool); =20 @@ -127,6 +128,10 @@ static inline u64 wbt_default_latency_nsec(struct requ= est_queue *q) { return 0; } +static inline bool wbt_disabled(struct request_queue *q) +{ + return true; +} =20 #endif /* CONFIG_BLK_WBT */ =20 --=20 2.31.1