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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 6324DC433DB for ; Wed, 13 Jan 2021 14:16:42 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 E0E27233FB for ; Wed, 13 Jan 2021 14:16:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0E27233FB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2E56D6EA01; Wed, 13 Jan 2021 14:16:41 +0000 (UTC) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by gabe.freedesktop.org (Postfix) with ESMTPS id 08D2C6EA01 for ; Wed, 13 Jan 2021 14:16:39 +0000 (UTC) IronPort-SDR: S99n4nui5yf1ngYZgyxTn5gMnQz5X4jdk19wmeBEMu33LDj7LNqi1Nvgiood7jQFuRAK43B75S +4SrcyHtzfsg== X-IronPort-AV: E=McAfee;i="6000,8403,9862"; a="157982873" X-IronPort-AV: E=Sophos;i="5.79,344,1602572400"; d="scan'208";a="157982873" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2021 06:16:39 -0800 IronPort-SDR: MEbv50MA+v/8aDl1Mey5z/BsuPdtu0AHd8jnDUY1WR9FUCcSOKopYMOP83Dq3+0Q+Vl+Zq/BYv 2r341NBESjtA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.79,344,1602572400"; d="scan'208";a="572037155" Received: from gaia.fi.intel.com ([10.237.72.192]) by fmsmga005.fm.intel.com with ESMTP; 13 Jan 2021 06:16:38 -0800 Received: by gaia.fi.intel.com (Postfix, from userid 1000) id 8E8FF5C2054; Wed, 13 Jan 2021 16:13:57 +0200 (EET) From: Mika Kuoppala To: Chris Wilson , intel-gfx@lists.freedesktop.org In-Reply-To: <20210113125939.10205-1-chris@chris-wilson.co.uk> References: <20210113125155.1029-1-chris@chris-wilson.co.uk> <20210113125939.10205-1-chris@chris-wilson.co.uk> Date: Wed, 13 Jan 2021 16:13:57 +0200 Message-ID: <87czy8lyai.fsf@gaia.fi.intel.com> MIME-Version: 1.0 Subject: Re: [Intel-gfx] [PATCH] drm/i915/selftests: Bump the scheduling threshold for fast heartbeats X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Chris Wilson Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Chris Wilson writes: > Since we are system_highpri_wq, we expected the heartbeat to be > scheduled promptly. However, we see delays of over 10ms upsetting our > assertions. Accept this as inevitable and bump the error threshold to > 20ms (from 6ms). > > Signed-off-by: Chris Wilson > --- > drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c | 13 ++++++++++--- > 1 file changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > index b88aa35ad75b..e88a01390dc5 100644 > --- a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > +++ b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > @@ -197,6 +197,7 @@ static int cmp_u32(const void *_a, const void *_b) > > static int __live_heartbeat_fast(struct intel_engine_cs *engine) > { > + const int error_threshold = max(20000, jffies_to_usecs(6)); s/jffies/jiffies Also for the commit message, 6 jiffies are not 6ms so it needs some mending. -Mika > struct intel_context *ce; > struct i915_request *rq; > ktime_t t0, t1; > @@ -254,12 +255,18 @@ static int __live_heartbeat_fast(struct intel_engine_cs *engine) > times[0], > times[ARRAY_SIZE(times) - 1]); > > - /* Min work delay is 2 * 2 (worst), +1 for scheduling, +1 for slack */ > - if (times[ARRAY_SIZE(times) / 2] > jiffies_to_usecs(6)) { > + /* > + * Ideally, the upper bound on min work delay would be something like > + * 2 * 2 (worst), +1 for scheduling, +1 for slack. In practice, we > + * are, even with system_wq_highpri, at the mercy of the CPU scheduler > + * and may be stuck behind some slow work for many millisecond. Such > + * as our very own display workers. > + */ > + if (times[ARRAY_SIZE(times) / 2] > error_threshold) { > pr_err("%s: Heartbeat delay was %uus, expected less than %dus\n", > engine->name, > times[ARRAY_SIZE(times) / 2], > - jiffies_to_usecs(6)); > + error_threshold); > err = -EINVAL; > } > > -- > 2.20.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx