From patchwork Thu Sep 22 11:35:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 12984988 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 DB21EC54EE9 for ; Thu, 22 Sep 2022 11:25:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231528AbiIVLZR (ORCPT ); Thu, 22 Sep 2022 07:25:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45918 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231488AbiIVLZP (ORCPT ); Thu, 22 Sep 2022 07:25:15 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8C5DAE236; Thu, 22 Sep 2022 04:25:13 -0700 (PDT) Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.53]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4MYCZF3PMLzHpmX; Thu, 22 Sep 2022 19:23:01 +0800 (CST) Received: from kwepemm600009.china.huawei.com (7.193.23.164) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 22 Sep 2022 19:25:12 +0800 Received: from huawei.com (10.175.127.227) by kwepemm600009.china.huawei.com (7.193.23.164) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 22 Sep 2022 19:25:11 +0800 From: Yu Kuai To: , , CC: , , , , Subject: [PATCH v3 1/5] wbt: don't show valid wbt_lat_usec in sysfs while wbt is disabled Date: Thu, 22 Sep 2022 19:35:54 +0800 Message-ID: <20220922113558.1085314-2-yukuai3@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220922113558.1085314-1-yukuai3@huawei.com> References: <20220922113558.1085314-1-yukuai3@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemm600009.china.huawei.com (7.193.23.164) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org 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 */