From patchwork Fri Dec 16 11:12:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kemeng Shi X-Patchwork-Id: 13074739 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 87375C4332F for ; Fri, 16 Dec 2022 03:13:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229879AbiLPDNi (ORCPT ); Thu, 15 Dec 2022 22:13:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229774AbiLPDNe (ORCPT ); Thu, 15 Dec 2022 22:13:34 -0500 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CCA82A969; Thu, 15 Dec 2022 19:13:32 -0800 (PST) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4NYDh70jPTz4f43Dd; Fri, 16 Dec 2022 11:13:27 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgAXiNVW4ptjHYxACQ--.50238S5; Fri, 16 Dec 2022 11:13:29 +0800 (CST) From: Kemeng Shi To: jack@suse.cz, paolo.valente@linaro.org, tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linfeilong@huawei.com, liuzhiqiang@26.com, shikemeng@huaweicloud.com Subject: [PATCH v2 03/10] block, bfq: initialize bfqq->decrease_time_jif correctly Date: Fri, 16 Dec 2022 19:12:23 +0800 Message-Id: <20221216111230.3638832-4-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20221216111230.3638832-1-shikemeng@huaweicloud.com> References: <20221216111230.3638832-1-shikemeng@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgAXiNVW4ptjHYxACQ--.50238S5 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr4Utw1kuw4fJr45tF4ruFg_yoW8AFy5pa 9Fgr47KF4jqFy3Wr1UAa1DGF98Krs09ry7J3W2g392y3yUArnFgFsYkrWYvFWfGrs7Aw10 qw4vqr9ruw1F9FJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmY14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2jI8I6cxK62vIxIIY0VWUZVW8XwA2048vs2IY02 0E87I2jVAFwI0_JrWl82xGYIkIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2 F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjx v20xvEc7CjxVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2 jsIEc7CjxVAFwI0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4 CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvj eVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I 1lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_ Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1V AY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAI cVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42 IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIev Ja73UjIFyTuYvjTRNzVbUUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Inject limit is updated or reset when time_is_before_eq_jiffies( decrease_time_jif + several msecs) or think-time state changes. decrease_time_jif is initialized to 0 and will be set to current jiffies when inject limit is updated or reset. If the jiffies is slightly greater than LONG_MAX, time_is_after_eq_jiffies(0) will keep for a long time, so as time_is_after_eq_jiffies(decrease_time_jif + several msecs). If the think-time state never chages, then the injection will not work as expected for long time. To be more specific: Function bfq_update_inject_limit maybe triggered when jiffies pasts decrease_time_jif + msecs_to_jiffies(10) in bfq_add_request by setting bfqd->wait_dispatch to true. Function bfq_reset_inject_limit are called in two conditions: 1. jiffies pasts bfqq->decrease_time_jif + msecs_to_jiffies(1000) in function bfq_add_request. 2. jiffies pasts bfqq->decrease_time_jif + msecs_to_jiffies(100) or bfq think-time state change from short to long. Fix this by initializing bfqq->decrease_time_jif to current jiffies to trigger service injection soon when service injection conditions are met. Signed-off-by: Kemeng Shi --- block/bfq-iosched.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 5a6d9e8c329d..9441fc98961a 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -5491,6 +5491,8 @@ static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, /* first request is almost certainly seeky */ bfqq->seek_history = 1; + + bfqq->decrease_time_jif = jiffies; } static struct bfq_queue **bfq_async_queue_prio(struct bfq_data *bfqd,