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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A4B1BC2BB55 for ; Wed, 15 Apr 2020 11:45:58 +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 7A92E21569 for ; Wed, 15 Apr 2020 11:45:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A92E21569 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk 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 DBE176E9A5; Wed, 15 Apr 2020 11:45:57 +0000 (UTC) Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id E3EF66E9A3 for ; Wed, 15 Apr 2020 11:45:55 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from localhost (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP (TLS) id 20905730-1500050 for multiple; Wed, 15 Apr 2020 12:45:53 +0100 MIME-Version: 1.0 In-Reply-To: <158694989939.24667.16243976890282267889@build.alporthouse.com> References: <20200414161423.23830-1-chris@chris-wilson.co.uk> <20200415105659.GA50947@intel.intel> <158694989939.24667.16243976890282267889@build.alporthouse.com> To: Andi Shyti From: Chris Wilson Message-ID: <158695115200.24667.1030399675561260215@build.alporthouse.com> User-Agent: alot/0.8.1 Date: Wed, 15 Apr 2020 12:45:52 +0100 Subject: Re: [Intel-gfx] [PATCH 1/2] drm/i915/gt: Try to smooth RPS spikes 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: intel-gfx@lists.freedesktop.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Quoting Chris Wilson (2020-04-15 12:24:59) > Quoting Andi Shyti (2020-04-15 11:56:59) > > Hi Chris, > > > > On Tue, Apr 14, 2020 at 05:14:22PM +0100, Chris Wilson wrote: > > > By the time we respond to the RPS interrupt [inside a worker], the GPU > > > may be running a different workload. As we look to make the evalution > > > intervals shorter, these spikes are more likely to okay. Let's try to > > > smooth over the spikes in the workload by comparing the EI interrupt > > > [up/down events] with the most recently completed EI; if both say up, > > > then increase the clocks, if they disagree stay the same. In principle, > > > this means we now take 2 up EI to go increase into the next bin, and > > > similary 2 down EI to decrease. However, if the worker runs fast enough, > > > the previous EI in the registers will be the same as triggered the > > > interrupt, so responsiveness remains unaffect. [Under the current scheme > > > where EI are on the order of 10ms, it is likely that this is true and we > > > compare the interrupt with the EI that caused it.] > > > > looks reasonable to me. Wouldn't it make also sense to evaluate > > the difference between the current and the previous pm_iir? > > I was considering it... We can't look at IIR since we apply the mask, > but ISR should be valid. Worth a looksee. [ 98.882025] bcs0: DOWN interrupt not recorded for idle, pm_iir:10, pm_isr:0, prev_down:0, down_threshold:3840, down_ei:5dc0 ISR doesn't seem helpful on first try. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx