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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 98B976E872; Wed, 25 Nov 2020 08:59:57 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0904E6E872 for ; Wed, 25 Nov 2020 08:59:55 +0000 (UTC) IronPort-SDR: rOhoMR7Tgy9GE62BF1dHqcFduCqRq8+LlL5IGMcjy2+7eNibm8dwTOxkZaZ16lJF67mnzJg2PL M/36n7gzQ6ug== X-IronPort-AV: E=McAfee;i="6000,8403,9815"; a="159138662" X-IronPort-AV: E=Sophos;i="5.78,368,1599548400"; d="scan'208";a="159138662" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Nov 2020 00:59:55 -0800 IronPort-SDR: 90PIu9bIyjMBi9JkIZxsikaxjPqA08zZuunosdfM3t/Rlkkv55Du5cNdx1sj0byLXx+52s1zr9 FfYBTzktxyKQ== X-IronPort-AV: E=Sophos;i="5.78,368,1599548400"; d="scan'208";a="547190330" Received: from jhaitov-mobl.ger.corp.intel.com (HELO [10.214.246.84]) ([10.214.246.84]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Nov 2020 00:59:53 -0800 To: Chris Wilson , intel-gfx@lists.freedesktop.org References: <20201124114219.29020-1-chris@chris-wilson.co.uk> <20201124114219.29020-7-chris@chris-wilson.co.uk> <160623952536.28476.8865484942445187968@build.alporthouse.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: <7c50999c-2285-326e-c8d2-54a210f991da@linux.intel.com> Date: Wed, 25 Nov 2020 08:59:51 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <160623952536.28476.8865484942445187968@build.alporthouse.com> Content-Language: en-US Subject: Re: [Intel-gfx] [PATCH 07/16] drm/i915/gt: Check for a completed last request once 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: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 24/11/2020 17:38, Chris Wilson wrote: > Quoting Tvrtko Ursulin (2020-11-24 17:19:23) >> >> On 24/11/2020 11:42, Chris Wilson wrote: >>> Pull the repeated check for the last active request being completed to a >>> single spot, when deciding whether or not execlist preemption is >>> required. >>> >>> Signed-off-by: Chris Wilson >>> --- >>> drivers/gpu/drm/i915/gt/intel_lrc.c | 15 ++++----------- >>> 1 file changed, 4 insertions(+), 11 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c >>> index cf11cbac241b..43703efb36d1 100644 >>> --- a/drivers/gpu/drm/i915/gt/intel_lrc.c >>> +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c >>> @@ -2141,12 +2141,9 @@ static void execlists_dequeue(struct intel_engine_cs *engine) >>> */ >>> >>> if ((last = *active)) { >>> - if (need_preempt(engine, last, rb)) { >>> - if (i915_request_completed(last)) { >>> - tasklet_hi_schedule(&execlists->tasklet); >>> - return; >>> - } >>> - >>> + if (i915_request_completed(last)) { >>> + goto check_secondary; >>> + } else if (need_preempt(engine, last, rb)) { >>> ENGINE_TRACE(engine, >>> "preempting last=%llx:%lld, prio=%d, hint=%d\n", >>> last->fence.context, >>> @@ -2174,11 +2171,6 @@ static void execlists_dequeue(struct intel_engine_cs *engine) >>> last = NULL; >>> } else if (need_timeslice(engine, last, rb) && >>> timeslice_expired(execlists, last)) { >>> - if (i915_request_completed(last)) { >>> - tasklet_hi_schedule(&execlists->tasklet); >>> - return; >>> - } >>> - >>> ENGINE_TRACE(engine, >>> "expired last=%llx:%lld, prio=%d, hint=%d, yield?=%s\n", >>> last->fence.context, >>> @@ -2214,6 +2206,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine) >>> * we hopefully coalesce several updates into a single >>> * submission. >>> */ >>> +check_secondary: >>> if (!list_is_last(&last->sched.link, >>> &engine->active.requests)) { >> >> Is there a tasklet_hi_schedule in here? I see set_timeslice in my checkout. > > That tasklet_hi_schedule() was a mistake. It just devolves into a > busy-spinner as we wait for HW to send the next event, which turns out > not to be as instantaneous as hoped. > > I recall leaving the imprint of my palm on my face when I figured out > what was causing the spike in the profile. Okay, if you mention that in the commit message you can add my rb. Regards, Tvrtko _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx