From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D453B41C72; Thu, 19 Dec 2024 01:21:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734571274; cv=none; b=BU7fw9g065FPlU4AVeaPv3BA2ZLz/p7hfW3gaO+kHv+GpoXVZo1Qf25w9cSwX6LlZkd3/frZBnq+7Jrp4DbRNk9oX2OTzH2bPQAOpFl7maPjREPIACy+PZTVU+MFAn2AsW7/NM6y/9AOSm/vld+KOz7Tyms4b24VqiieXkAngrE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734571274; c=relaxed/simple; bh=muQ4ssRslj9k5J2L/MtfZQ1SOg0fisQiTrx15+/aL8o=; h=Subject:To:Cc:References:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=tVKv4uBm52kwkq1jJNwhNYMQQsfTF+Q3ZxONVTMDaTIbBSmKiU6nDRoL6P7sMfM/A4XOj2nmwbEwjkyrRh9/0Rmc4ds1qNyp3msMb/XUn3mVFFQzCUlqHXbNMv4/LHs5cY2pvYfAtGAedQLUZop7Gcd0BpK2LEuyxBdjRYXxNwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4YDCRM4LMxz4f3jY1; Thu, 19 Dec 2024 09:20:47 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 222301A058E; Thu, 19 Dec 2024 09:21:07 +0800 (CST) Received: from [10.174.176.73] (unknown [10.174.176.73]) by APP4 (Coremail) with SMTP id gCh0CgAnT4MBdWNnzWEBFA--.11064S3; Thu, 19 Dec 2024 09:21:06 +0800 (CST) Subject: Re: [PATCH RFC v2 4/4] block/mq-deadline: introduce min_async_depth To: Bart Van Assche , Yu Kuai , axboe@kernel.dk, akpm@linux-foundation.org, ming.lei@redhat.com, yang.yang@vivo.com, osandov@fb.com, paolo.valente@linaro.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, "yukuai (C)" References: <20241217024047.1091893-1-yukuai1@huaweicloud.com> <20241217024047.1091893-5-yukuai1@huaweicloud.com> <8fa8c620-22ff-0963-d1ee-c6fe6f13b49c@huaweicloud.com> <96556f82-b511-b3ef-01b5-e9a32557db95@huaweicloud.com> From: Yu Kuai Message-ID: Date: Thu, 19 Dec 2024 09:21:04 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-CM-TRANSID:gCh0CgAnT4MBdWNnzWEBFA--.11064S3 X-Coremail-Antispam: 1UD129KBjvdXoWrZrWrKF1xGF1xCF4rWFyfJFb_yoW3WFX_Wr 1qyryvgwnY9rn3ta1jvr15W3y3Gr4DGFn3Wa9rW3W5ta4YgasxWrZrAws5Zr43X3y0gr1k uayI93y09w4agjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbfkFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_ Gr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s 0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xII jxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr 1lF7xvr2IY64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY 04v7Mxk0xIA0c2IEe2xFo4CEbIxvr21lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2I x0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK 8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I 0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUonmRUUUUU X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ Hi, 在 2024/12/19 2:00, Bart Van Assche 写道: > On 12/17/24 5:14 PM, Yu Kuai wrote: >> I can't make this read-write, because set lower value will cause >> problems for existing elevator, because wake_batch has to be >> updated as well. > > Should the request queue perhaps be frozen before wake_batch is updated? Yes, we should. The good thing is for now it's frozen already: - update nr_requests context; - switch elevator; However, if you mean do this while writing async_depth, freeze queue is not enough, we have to ping all the hctx as well by q->sysfs_lock, which is not possible. Or if you mean do this while write the new min_async_depth, then we have to update wat_batch for all the queues in the system, too crazy for me... Thanks, Kuai > > Thanks, > > Bart. > > . >