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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 6FAE5C28CC3 for ; Thu, 30 May 2019 09:28:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 494CD254E4 for ; Thu, 30 May 2019 09:28:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="QtLbf2Hm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727428AbfE3J2B (ORCPT ); Thu, 30 May 2019 05:28:01 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:38462 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726382AbfE3J2B (ORCPT ); Thu, 30 May 2019 05:28:01 -0400 Received: by mail-wr1-f66.google.com with SMTP id d18so3705997wrs.5; Thu, 30 May 2019 02:28:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=V9uS1keBW3VpEfdw8YbBt35z4e82IzpdzTkrruky1E8=; b=QtLbf2HmeJA14Jf1AcY7WgDdWbr0B/C84z9/ERtg1Ea1H9PTS7kqNhnGKZY+dPDjPC KbeOi8QpjT2t0+jlvl05Jq58LCsRl6NXwYmKRMqm8AAsQqi/VENdBGl0EZJ2mpl1nHRR QibgPIATXT/RCX7UeeCr5m7mPYg+ih/oV9mwM1UXYkokeIoQCqhLRSlhCDQ87MxU4r6v HtRYiITzXvN1mLjGpneqU5cAIEVRoxDLlvtFFHlIY0iDXjG3QP00tVAKZUf93GH+HQ5n iOKumKG/s83Lb1HPwNeapI2hCHj1xk/HotATLvhC7rJbvJTD/ajL9rfERTfhO0OPqSsr m8ug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=V9uS1keBW3VpEfdw8YbBt35z4e82IzpdzTkrruky1E8=; b=VAuPRknRfwLoPuavE7DF9XI97OhYOa0Ep41HUoOkO5NeddUyBVw/SQRZmps0lBzP7d P/LdzhUE1+aXHyV1b1vpJJwiS6kuJ6VdqklsWmQ1/POxM/9u28NbzkuSMu6gBMev6jT0 M+b+LZVM6XJJuy648f/AWNKy5Xwg/Cd2Co4nLJJteXxK34Nth7IIee2H4OsLXuLYFiF/ srPEwA55/7xlJ3goDQtSSn6vwfxAMw8bbsjctNCzXlIX6aMGhFkxBuj3eIUlKVZ1WtfC BYd81E7zKRdhgAI6SI35bR89aaA/Ke2kmyM0Oup69zL8BR6g2bpttXAa98cNNXVw61AW yf7A== X-Gm-Message-State: APjAAAUipeuswXVT2C6y3XyKHNr0IjTO+P/4fVahDO7W0XoRkAH6Mp4g oMat//FNHXi5LckzBQxNn24= X-Google-Smtp-Source: APXvYqwAYe7240hTlEiIsSSbTkHNnMmocCkj0k5gjshu065TwpUUnlDOU/rPhN+bZXP3GcvjnesCAQ== X-Received: by 2002:adf:fd09:: with SMTP id e9mr1920656wrr.292.1559208479457; Thu, 30 May 2019 02:27:59 -0700 (PDT) Received: from localhost.localdomain ([109.126.142.5]) by smtp.gmail.com with ESMTPSA id u25sm147605wmc.3.2019.05.30.02.27.57 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 30 May 2019 02:27:58 -0700 (PDT) From: "Pavel Begunkov (Silence)" To: Jens Axboe , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: osandov@fb.com, ming.lei@redhat.com, Hou Tao , Pavel Begunkov Subject: [PATCH v2 1/1] blk-mq: Fix disabled hybrid polling Date: Thu, 30 May 2019 12:27:08 +0300 Message-Id: <71c31759a882e00f156a8434caed7064ec93d3da.1559208134.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pavel Begunkov Commit 4bc6339a583cec650b05 ("block: move blk_stat_add() to __blk_mq_end_request()") moved blk_stat_add() to reuse ktime_get_ns(), so now it's called after blk_update_request(), which zeroes rq->__data_len. Without length, blk_stat_add() can't calculate stat bucket and returns error, effectively disabling hybrid polling. v2: Hybrid polling needs pure io time for precision, but according to the feedback from Omar Sandoval other components require end-to-end time. So, it can't be reused, and should be sampled twice insted. Signed-off-by: Pavel Begunkov --- block/blk-mq.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 32b8ad3d341b..907799282d57 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -537,11 +537,6 @@ inline void __blk_mq_end_request(struct request *rq, blk_status_t error) if (blk_mq_need_time_stamp(rq)) now = ktime_get_ns(); - if (rq->rq_flags & RQF_STATS) { - blk_mq_poll_stats_start(rq->q); - blk_stat_add(rq, now); - } - if (rq->internal_tag != -1) blk_mq_sched_completed_request(rq, now); @@ -580,6 +575,11 @@ static void __blk_mq_complete_request(struct request *rq) int cpu; WRITE_ONCE(rq->state, MQ_RQ_COMPLETE); + + if (rq->rq_flags & RQF_STATS) { + blk_mq_poll_stats_start(rq->q); + blk_stat_add(rq, ktime_get_ns()); + } /* * Most of single queue controllers, there is only one irq vector * for handling IO completion, and the only irq's affinity is set -- 2.21.0