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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 BE123C4740A for ; Mon, 9 Sep 2019 23:15:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9AEAF20863 for ; Mon, 9 Sep 2019 23:15:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389222AbfIIXP3 (ORCPT ); Mon, 9 Sep 2019 19:15:29 -0400 Received: from mail-ot1-f65.google.com ([209.85.210.65]:40701 "EHLO mail-ot1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730900AbfIIXP3 (ORCPT ); Mon, 9 Sep 2019 19:15:29 -0400 Received: by mail-ot1-f65.google.com with SMTP id y39so15201887ota.7; Mon, 09 Sep 2019 16:15:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=76+B0F+y6GF7x1pmO705M0ab149/3jefLlEAKzhXfdY=; b=ny6T50Z+UdF6y8uSXXKKUc9fU1AC13p4lMW3Oy0elxaJ/rTHUfx1IkPZMvCf3vg/9G /itfv5b9Z+e3KGNXqt4LG7SPUDI2PGGQwVhPSZGyaNEYGRXL3Ie3E5UkQbvirmunXOhR qJ6LG2NxKaWvhA6ScbFbbbN7eRDoiq6nGBoIPdNpQu82c/ir5eT82opkojuAR2n7PX3T mkLVSLjuL2w2AyXsfEjqUKY1awwvKlWBpY21t3kVGTebIoI1WLydiW9ATMs5WLWleZip hbWBtwvVdl8SRhGaFdqvZ5AOnRNfd2iOHFJ7PRQ2upZs1/W4G+fnjBl9jWxpKZ5ZixQo Vbpg== X-Gm-Message-State: APjAAAUjEfbgF4PNmae4/DaNcSNRoZZQOkT8QUzdKzYIdoUcBVxc3dCJ HKmO0C6YT5LUfO7Sk0q4Hoo= X-Google-Smtp-Source: APXvYqw8MteVMDy0Cl8ZOyqZEdlruprk+5eF7K1KC+eC19R7iANjgOvPKaYiMx6uYRtoPSCqFx1Cbw== X-Received: by 2002:a9d:4815:: with SMTP id c21mr18066036otf.26.1568070928432; Mon, 09 Sep 2019 16:15:28 -0700 (PDT) Received: from ?IPv6:2600:1700:65a0:78e0:514:7862:1503:8e4d? ([2600:1700:65a0:78e0:514:7862:1503:8e4d]) by smtp.gmail.com with ESMTPSA id l30sm6462344otl.74.2019.09.09.16.15.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Sep 2019 16:15:27 -0700 (PDT) Subject: Re: [PATCH v8 13/13] nvmet-passthru: support block accounting To: Logan Gunthorpe , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Chaitanya Kulkarni , Stephen Bates , Jens Axboe , Keith Busch , Max Gurtovoy , Christoph Hellwig References: <20190828215429.4572-1-logang@deltatee.com> <20190828215429.4572-14-logang@deltatee.com> <92d61426-65a2-827c-936b-55f12f3d6afb@grimberg.me> <7954e8a4-6026-2210-7192-94a4e483facf@grimberg.me> From: Sagi Grimberg Message-ID: Date: Mon, 9 Sep 2019 16:15:25 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org >>>>> Support block disk accounting by setting the RQF_IO_STAT flag >>>>> and gendisk in the request. >>>>> >>>>> After this change, IO counts will be reflected correctly in >>>>> /proc/diskstats for drives being used by passthru. >>>>> >>>>> Signed-off-by: Logan Gunthorpe >>>>> --- >>>>> drivers/nvme/target/io-cmd-passthru.c | 5 ++++- >>>>> 1 file changed, 4 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/drivers/nvme/target/io-cmd-passthru.c b/drivers/nvme/target/io-cmd-passthru.c >>>>> index 7557927a3451..63f12750a80d 100644 >>>>> --- a/drivers/nvme/target/io-cmd-passthru.c >>>>> +++ b/drivers/nvme/target/io-cmd-passthru.c >>>>> @@ -410,6 +410,9 @@ static struct request *nvmet_passthru_blk_make_request(struct nvmet_req *req, >>>>> if (unlikely(IS_ERR(rq))) >>>>> return rq; >>>>> >>>>> + if (blk_queue_io_stat(q) && cmd->common.opcode != nvme_cmd_flush) >>>>> + rq->rq_flags |= RQF_IO_STAT; >>> >>> Thanks for the review! >>> >>>> Does flush has data bytes in the request? Why the special casing? >>> >>> Well it was special cased in the vanilla blk account flow... But I think >>> it's required to be special cased so the IO and in_flight counts don't >>> count flushes (as they do not for regular block device traffic). >> >> I think that the accounting exclude I/O that is yielded from the flush >> sequence. Don't think its relevant here... > > What? Per blk_account_io_done(), RQF_FLUSH_SEQ will not be set by us for > passthru commands and I don't think it's appropriate to do so. Thus, if > we set RQF_IO_STAT for passthru flush commands, they will be counted > which we do not want. Have you considered to have nvmet_passthru_blk_make_request set RQF_FUA for nvme_cmd_flush? this way blk_insert_flush will be called and RQF_FLUSH_SEQ will be set and you don't need to worry about this special casing...