From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 008.lax.mailroute.net (008.lax.mailroute.net [199.89.1.11]) (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 8D7E217BA1; Tue, 3 Sep 2024 17:32:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725384722; cv=none; b=KPC/FJZn8cAD8OekuHyvjx4GC3IHZaGMgmjM5ax2kiCGALPzeLKJnZrv67VjvfNmBRNGK4jYNYIbnUiB75/3Kwh2xtHUM9LulkI6t1/RUwub1mjUsfohKs0EmUNxX1cEQBfgGDjdWSmPGMlxg11oc532j7aaVt98yB7ESRTLu8w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725384722; c=relaxed/simple; bh=YNJvZ10III8fSzlNqoOO8Yi3tp6FC0ZOEsOObcglD+8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fGW4pAXAnTfyjlrQ7Yc7RLV2rnuntobXAORCZkBu1Pu4kkNqCbbwESq1Gti3yaLOKpcaLr7QFQkId9hVEisoJy+YNLZaJdyna467V8lOBWzk3gge4hit/ojeVvoPKRDpoGQDfxGnnD4BV04Vv0zLz9C9X0WsbuL7P6l39Qj67EM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=cUlfnWoh; arc=none smtp.client-ip=199.89.1.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="cUlfnWoh" Received: from localhost (localhost [127.0.0.1]) by 008.lax.mailroute.net (Postfix) with ESMTP id 4WyszR67vtz6ClY96; Tue, 3 Sep 2024 17:28:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1725384513; x=1727976514; bh=ETztvBENBFjFa2gtk14V2B70 sTk4L6Jv4z6bXiLJo50=; b=cUlfnWoh3aYMyiQiBxdJbLKqiePWdx2g6demDFze Blp7qKf5B7orQrTQ4UIAh92PDAud9g3yJw682SxO0Gkyb0Yr1BsrCeALG25Cnvpt Cm9aCvVSeCtH0xWar+tnzIGNo0stnjLpc0i16OMxa0bSVkkMw9j2LXRsm0X4uiXS Vm4p2mEBxSTIG4/RR44FGO4khmTLE/4pcPRUoO1A3tVQaeOrhjWf8QRPPb9JFS+k F1X1mbh+w0vmUIuCmZzpNUkQPdtUnK/Pv38eH6qJHv2cPNjAS3Q8FqZ352a73moq ApKjgx8Vg/4kifdwKPjCOtXe3lX+P7qj4qySkgGn6TFQSg== X-Virus-Scanned: by MailRoute Received: from 008.lax.mailroute.net ([127.0.0.1]) by localhost (008.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id zgjE9tvZc3mS; Tue, 3 Sep 2024 17:28:33 +0000 (UTC) Received: from [100.66.154.22] (unknown [104.135.204.82]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 008.lax.mailroute.net (Postfix) with ESMTPSA id 4WyszP3YDXz6ClY93; Tue, 3 Sep 2024 17:28:33 +0000 (UTC) Message-ID: <769fb0e4-6f55-4a2d-a0f2-e8836b790617@acm.org> Date: Tue, 3 Sep 2024 10:28:32 -0700 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] block: move non sync requests complete flow to softirq To: ZhangHui , axboe@kernel.dk Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20240903115437.42307-1-zhanghui31@xiaomi.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20240903115437.42307-1-zhanghui31@xiaomi.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/3/24 4:54 AM, ZhangHui wrote: > Currently, for a controller that supports multiple queues, like UFS4.0, > the mq_ops->complete is executed in the interrupt top-half. Therefore, > the file system's end io is executed during the request completion process, > such as f2fs_write_end_io on smartphone. > > However, we found that the execution time of the file system end io > is strongly related to the size of the bio and the processing speed > of the CPU. Because the file system's end io will traverse every page > in bio, this is a very time-consuming operation. > > We measured that the 80M bio write operation on the little CPU will > cause the execution time of the top-half to be greater than 100ms. > The CPU tick on a smartphone is only 4ms, which will undoubtedly affect > scheduling efficiency. > > Let's fixed this issue by moved non sync request completion flow to > softirq, and keep the sync request completion in the top-half. An explanation is missing from the patch description why this issue cannot be solved by changing rq_affinity to 2. Thanks, Bart.