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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,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 54989C432C2 for ; Wed, 25 Sep 2019 23:02:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A78F20640 for ; Wed, 25 Sep 2019 23:02:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569452548; bh=aF5eWj/Bp4MAgMXMsU/tILGukQe7wEsm+krU50KJ4aM=; h=Date:From:To:Cc:Subject:List-ID:From; b=2IxXubNxVheoFzAJ1PMEGbp+Gg7ZZq/B4U4j1765TK18lgvwgHxxMCoYIaLULDiAZ 6AFNGva8nXoFWrKkAgwtiPNH0YLxyubiDewlcFDc6+TXVZ27JGwD86rzH2YZlvtUHw 5Net5Jffu+PRYl5f+a9OD58slxP5UUPQvqun8ndc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727368AbfIYXCY (ORCPT ); Wed, 25 Sep 2019 19:02:24 -0400 Received: from mail-qk1-f194.google.com ([209.85.222.194]:43125 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726921AbfIYXCY (ORCPT ); Wed, 25 Sep 2019 19:02:24 -0400 Received: by mail-qk1-f194.google.com with SMTP id h126so195627qke.10; Wed, 25 Sep 2019 16:02:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=J6xx84NYBZMzyAcWsbF/M7RN9YSA/RHntuLBn1Nqazg=; b=SIfEzvpvUIu7/aCIY6SH2SkyCjOd9o0i5PqDvqyQHvE2InvTaTZQsVQCaxK5q1n/Cj yumJMyFWRX5aLUZd6WU9ijwVcG7VOjbiBe83nr6b6ydDBgYuXARTJf9DFAPC08+spzNo lUUQILezVaRYjlSnhG9eGY0RP1Hd2B2Vt9F8TaDReIT63toDYPKKzmTKEbTR868/tRhG AlAKT1UT4L82ewB5aZ1Sz017fFwxNLGqgxsyPmzjD7ZzoHFV7NWhiDpx9tVnBa86/yP+ YgSGjq91jgvX1ZBsL/sJT2p9Dmg68iJXvjHCqi5Yt4gQ8UoZIivfDeKn7jA2r66/x0R5 ou0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :mime-version:content-disposition:user-agent; bh=J6xx84NYBZMzyAcWsbF/M7RN9YSA/RHntuLBn1Nqazg=; b=hPAp7SNGvOncwU8XdsEPoAA35NumTULvoxTqdRAyIx4/m2FizTJelAWE7Y6L0jSO0q EWa5CFV3blOH3eBtHh1H6T9jC+da9qJ+XKoSq5aYsFQC7wfU5RPL/Mto58BBJ4e0U4c8 xPCJec/3mdfax7D/sLsRhl0mTvdqDVX0lAhdxyxF+1n86UEwen29KXcxl8RhQzbQUNFN 5+KN9rJRCPxNf3DgH2niORDrY4oc5uDHLKYKtaY2qHuyMXkAPw96NyXiNKkWGTvY4IPN xXaAuFN0rDPHtlDStppFZ1DFAxJGTtwODzPh0tzyvsJ6ntl6l6ds5B7bzmyATTNET8ES hMeg== X-Gm-Message-State: APjAAAWfKNdytNvl1XH6ZcOqZcupAD/LUMtK+Hl9sD2R2gZRYsxjkmYn fZLKYkgHRgEyTe8iTzf92Yg= X-Google-Smtp-Source: APXvYqzlN0SByh/FHkgjqHVCuxYeLgWE2FPBsrHJAD9J0BHXXCNAE+h7pH/AOECmnivaxcM7ltQ9Ow== X-Received: by 2002:a37:ef11:: with SMTP id j17mr391810qkk.1.1569452542573; Wed, 25 Sep 2019 16:02:22 -0700 (PDT) Received: from localhost ([2620:10d:c091:500::3:a001]) by smtp.gmail.com with ESMTPSA id c41sm301087qte.8.2019.09.25.16.02.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 25 Sep 2019 16:02:20 -0700 (PDT) Date: Wed, 25 Sep 2019 16:02:07 -0700 From: Tejun Heo To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, cgroups@vger.kernel.org Subject: [PATCH 1/3 for-5.4/block] iocost: better trace vrate changes Message-ID: <20190925230207.GI2233839@devbig004.ftw2.facebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org vrate_adj tracepoint traces vrate changes; however, it does so only when busy_level is non-zero. busy_level turning to zero can sometimes be as interesting an event. This patch also enables vrate_adj tracepoint on other vrate related events - busy_level changes and non-zero nr_lagging. Signed-off-by: Tejun Heo --- Hello, Jens. I've encountered vrate regulation issues while testing on a hard disk machine. These are three patches to improve vrate adj visibility and fix the issue. Thanks. block/blk-iocost.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1343,7 +1343,7 @@ static void ioc_timer_fn(struct timer_li u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM]; u32 missed_ppm[2], rq_wait_pct; u64 period_vtime; - int i; + int prev_busy_level, i; /* how were the latencies during the period? */ ioc_lat_stat(ioc, missed_ppm, &rq_wait_pct); @@ -1531,6 +1531,7 @@ skip_surplus_transfers: * and experiencing shortages but not surpluses, we're too stingy * and should increase vtime rate. */ + prev_busy_level = ioc->busy_level; if (rq_wait_pct > RQ_WAIT_BUSY_PCT || missed_ppm[READ] > ppm_rthr || missed_ppm[WRITE] > ppm_wthr) { @@ -1592,6 +1593,10 @@ skip_surplus_transfers: atomic64_set(&ioc->vtime_rate, vrate); ioc->inuse_margin_vtime = DIV64_U64_ROUND_UP( ioc->period_us * vrate * INUSE_MARGIN_PCT, 100); + } else if (ioc->busy_level != prev_busy_level || nr_lagging) { + trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate), + &missed_ppm, rq_wait_pct, nr_lagging, + nr_shortages, nr_surpluses); } ioc_refresh_params(ioc, false);