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 0523BC33CB1 for ; Thu, 16 Jan 2020 14:40:50 +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 D5C7320684 for ; Thu, 16 Jan 2020 14:40:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D5C7320684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ACULAB.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 7035C6ED4C; Thu, 16 Jan 2020 14:40:49 +0000 (UTC) X-Greylist: delayed 2516 seconds by postgrey-1.36 at gabe; Thu, 16 Jan 2020 14:40:47 UTC Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [146.101.78.151]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7B2D36ED4C for ; Thu, 16 Jan 2020 14:40:47 +0000 (UTC) Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-171-fDFVhRh3N8mnBNjnwpGscQ-1; Thu, 16 Jan 2020 14:40:44 +0000 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Thu, 16 Jan 2020 14:40:44 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Thu, 16 Jan 2020 14:40:44 +0000 From: David Laight To: 'Chris Wilson' , 'Daniel Vetter' Thread-Topic: [PATCH] drm: Inject a cond_resched() into long drm_clflush_sg() Thread-Index: AQHVy+gMprmlNntzX0qJh6CaHCkwb6fs20gAgAANToCAAEszQIAABVIAgAAWQUCAAAyNcA== Date: Thu, 16 Jan 2020 14:40:43 +0000 Message-ID: References: <20200115205245.2772800-1-chris@chris-wilson.co.uk> <20200116065242.GC8400@dvetter-linux.ger.corp.intel.com> <157916041994.14122.8524532515240369595@skylake-alporthouse-com> <8f6b9daa2af342a79137064203255242@AcuMS.aculab.com> <157917771007.2795.953028640868055754@skylake-alporthouse-com> <90de9ae911dc481f9c2c62e196b2bacf@AcuMS.aculab.com> In-Reply-To: <90de9ae911dc481f9c2c62e196b2bacf@AcuMS.aculab.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-MC-Unique: fDFVhRh3N8mnBNjnwpGscQ-1 X-Mimecast-Spam-Score: 0 Subject: Re: [Intel-gfx] [PATCH] drm: Inject a cond_resched() into long drm_clflush_sg() 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'" , "'dri-devel@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" > I'll do some measurements later this afternoon. This is an Ivy bridge cpu, so clflush (not clflushopt). With a cond_resched for every page I get: (Note these calls are every 10 seconds....) # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) # 3155.126 us | drm_clflush_sg [drm](); 1) # 3067.382 us | drm_clflush_sg [drm](); 2) # 3063.766 us | drm_clflush_sg [drm](); 3) # 3092.302 us | drm_clflush_sg [drm](); 0) # 3209.486 us | drm_clflush_sg [drm](); ------------------------------------------ 0) kworker-7 => kworker-319 ------------------------------------------ 0) # 3633.803 us | drm_clflush_sg [drm](); ------------------------------------------ 1) kworker-7 => kworker-319 ------------------------------------------ 1) # 3090.278 us | drm_clflush_sg [drm](); 2) # 3828.108 us | drm_clflush_sg [drm](); 3) # 3049.836 us | drm_clflush_sg [drm](); ------------------------------------------ 3) kworker-319 => kworker-7 ------------------------------------------ 3) # 3295.017 us | drm_clflush_sg [drm](); 3) # 3064.077 us | drm_clflush_sg [drm](); ------------------------------------------ 0) kworker-319 => kworker-7 ------------------------------------------ 0) # 3182.034 us | drm_clflush_sg [drm](); ------------------------------------------ 3) kworker-7 => kworker-319 ------------------------------------------ 3) # 3065.754 us | drm_clflush_sg [drm](); ------------------------------------------ 2) kworker-319 => kworker-7 ------------------------------------------ 2) # 3562.513 us | drm_clflush_sg [drm](); ------------------------------------------ 3) kworker-319 => kworker-7 ------------------------------------------ 3) # 3048.914 us | drm_clflush_sg [drm](); 3) # 3062.469 us | drm_clflush_sg [drm](); 3) # 3055.727 us | drm_clflush_sg [drm](); ------------------------------------------ 0) kworker-7 => kworker-319 ------------------------------------------ Without the cond_sched I suspect more of them are 3.0ms. Not really a significant difference. I guess the longer times are the scheduler looking for work? I don't understand the extra traces - I'm guessing they are process switch related. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales) _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx