From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 220E2C433DB for ; Mon, 11 Jan 2021 03:48:35 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CC14B221ED for ; Mon, 11 Jan 2021 03:48:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC14B221ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XEaBnfdgKrj9SQkvtePWdD0yJL907R6V6mT7V56sWAc=; b=S3OVTA2rqay/vzTLZ5Qj+wCIb DzR+yWNIR5F6ZgvyHMKRYuhOd1jJHekNlXh2mZvwkAFI8S9IA7Z4q4+UrvauldoXOSAavh/ivJHbT fTJ50iSiasxz+lbIlHngVTEkr/ZlwcQ+xJpfhyplhGzqH4fCXL3ghqqAeFv121udmDyDHMjnF8qy7 jfoYb18u7yFGoAyTq2HEduPfIIikL0mhmYhiL0b9LVSzvwuvibKC3vXZArj/KWKN+FC3ZAUiqlrBB gFiuLD5KZ5xlxyb8v6Gv4LSRsMAWy40+fJiMCcJmp+yu5KKwF9apZDMaEeK+/nxrQuWLf2aY/aSpP d8zYSukyA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyoBn-0006vV-Te; Mon, 11 Jan 2021 03:48:19 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyoBe-0006rS-V7 for linux-nvme@lists.infradead.org; Mon, 11 Jan 2021 03:48:12 +0000 Received: from DGGEMM403-HUB.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4DDfll18C8z5G97; Mon, 11 Jan 2021 11:46:59 +0800 (CST) Received: from dggema772-chm.china.huawei.com (10.1.198.214) by DGGEMM403-HUB.china.huawei.com (10.3.20.211) with Microsoft SMTP Server (TLS) id 14.3.498.0; Mon, 11 Jan 2021 11:47:58 +0800 Received: from [10.169.42.93] (10.169.42.93) by dggema772-chm.china.huawei.com (10.1.198.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1913.5; Mon, 11 Jan 2021 11:47:57 +0800 Subject: Re: [PATCH 3/3] nvme: add parameter command_retry to enable retry To: Minwoo Im , References: <20210108144659.7126-1-minwoo.im.dev@gmail.com> <20210108144659.7126-4-minwoo.im.dev@gmail.com> From: Chao Leng Message-ID: Date: Mon, 11 Jan 2021 11:47:56 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20210108144659.7126-4-minwoo.im.dev@gmail.com> Content-Language: en-US X-Originating-IP: [10.169.42.93] X-ClientProxiedBy: dggeme712-chm.china.huawei.com (10.1.199.108) To dggema772-chm.china.huawei.com (10.1.198.214) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210110_224811_288846_1728128E X-CRM114-Status: GOOD ( 21.84 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 2021/1/8 22:46, Minwoo Im wrote: > nvme_init_request() has set REQ_FAILFAST_DRIVER to make requests > non-retryable. This command flag value is checked in > nvme_decide_disposition() to decide whether to RETRY or other > operations. In that point, blk_noretry_request() macro will be used to > check if command flags have one of REQ_FAILFAST_*. If so, it just > decides to complete the request without retrying. > > This patch added a module parameter named command_retry to turn on the > command retry feature in this driver. If turning it on, > REQ3_FAILFAST_DRIVER will not be set to requests so that retry can be > reached out to nvme_retry_req() based on the module parameter. > > Signed-off-by: Minwoo Im > --- > drivers/nvme/host/core.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c > index 6e428fdc25a8..e1836ca9956f 100644 > --- a/drivers/nvme/host/core.c > +++ b/drivers/nvme/host/core.c > @@ -44,6 +44,10 @@ static unsigned char shutdown_timeout = 5; > module_param(shutdown_timeout, byte, 0644); > MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown"); > > +static bool command_retry; > +module_param(command_retry, bool, 0644); > +MODULE_PARM_DESC(command_retry, "retry commands up to nvme_max_retries"); > + > static u8 nvme_max_retries = 5; > module_param_named(max_retries, nvme_max_retries, byte, 0644); > MODULE_PARM_DESC(max_retries, "max number of retries a command may have"); > @@ -560,7 +564,8 @@ static inline void nvme_init_request(struct request *req, > else /* no queuedata implies admin queue */ > req->timeout = NVME_ADMIN_TIMEOUT; > > - req->cmd_flags |= REQ_FAILFAST_DRIVER; > + if (!command_retry) > + req->cmd_flags |= REQ_FAILFAST_DRIVER; In abnormal scenarios, such as request time out, connection process may takes long time or the admin command waits for long time. Retry only for non-host errors may be a better choice. Maybe we can make some optimizations in nvme_decide_disposition. > nvme_clear_nvme_request(req); > nvme_req(req)->cmd = cmd; > } > _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme