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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 4DDD0C433F5 for ; Fri, 18 Feb 2022 09:21:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B1C5C10F143; Fri, 18 Feb 2022 09:21:34 +0000 (UTC) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTPS id 300F810F141; Fri, 18 Feb 2022 09:21:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645176093; x=1676712093; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=su/3T94pVDNsaL5hedw6oR2jhqFC6VvwaIdbglb4bg0=; b=WdtkrdI7gXrVKMz8NwoKGi44g3zJvWg8kyDM8ipcX/lKacKDMyg3eB+5 KHaQDdGx0GWAltiW/ZRnYRDrizHVvhrSUE5LZUlv2UfWMKIRCGkHDPmUz ZZT7+96SP8FPQyx/lQ8N03sFak4+DSo9Gfpsg5KmGiP1RgCIVNBrkmdaL ds1+FHZTHLRlgsMTZXG+FAtN73I7MZTRvV+eiKBsMsI5pU/pBKx9CMvO/ KxoWoWJVgOWvRz1o7hMiGJkbE5AENgfujsAu7u1MruYktigvL/9RhUExs eZ0Q++fAabx1haQbltBzZsQNDobW4mFjfU4ljFUql1XqUWFUQX3NkI0Io g==; X-IronPort-AV: E=McAfee;i="6200,9189,10261"; a="248687127" X-IronPort-AV: E=Sophos;i="5.88,378,1635231600"; d="scan'208";a="248687127" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Feb 2022 01:21:32 -0800 X-IronPort-AV: E=Sophos;i="5.88,378,1635231600"; d="scan'208";a="546205177" Received: from dkalinic-mobl.ger.corp.intel.com (HELO intel.com) ([10.249.33.147]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Feb 2022 01:21:30 -0800 Date: Fri, 18 Feb 2022 10:21:26 +0100 From: Andi Shyti To: Tvrtko Ursulin Message-ID: References: <20220217144158.21555-1-andi.shyti@linux.intel.com> <20220217144158.21555-6-andi.shyti@linux.intel.com> <12c2fcf8-ef3b-e59c-fe1e-23bc8f12cfe5@linux.intel.com> <57edfc5a-a330-8661-1509-b375f67b495e@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <57edfc5a-a330-8661-1509-b375f67b495e@linux.intel.com> Subject: Re: [Intel-gfx] [PATCH v5 5/7] drm/i915/gt: Create per-tile RC6 sysfs interface 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 , Lucas De Marchi , DRI Devel , Chris Wilson , Matthew Auld Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Tvrtko, > > > > Now tiles have their own sysfs interfaces under the gt/ > > > > directory. Because RC6 is a property that can be configured on a > > > > tile basis, then each tile should have its own interface > > > > > > > > The new sysfs structure will have a similar layout for the 4 tile > > > > case: > > > > > > > > /sys/.../card0 > > > > ├── gt > > > > │   ├── gt0 > > > > │   │   ├── id > > > > │   │   ├── rc6_enable > > > > │   │   ├── rc6_residency_ms > > > > . . . > > > > . . . > > > > . . > > > > │   └── gtN > > > > │   ├── id > > > > │   ├── rc6_enable > > > > │   ├── rc6_residency_ms > > > > │ . > > > > │ . > > > > │ > > > > └── power/ -+ > > > > ├── rc6_enable | Original interface > > > > ├── rc6_residency_ms +-> kept as existing ABI; > > > > . | it multiplexes over > > > > . | the GTs > > > > -+ > > > > > > > > The existing interfaces have been kept in their original location > > > > to preserve the existing ABI. They act on all the GTs: when > > > > reading they provide the average value from all the GTs. > > > > > > Average feels very odd to me. I'd ask if we can get away providing an errno > > > instead? Or tile zero data? > > > > Real multiplexing would be providing something when reading and > > when writing. The idea of average came while revieweing with > > Chris the write multiplexing. Indeed it makes sense to provide > > some common value, but I don't know how useful it can be to the > > user (still if the user needs any average). > > > > Joonas, Chris... any idea? > > > > > Case in point, and please correct me if I am wrong, legacy rc6_enable > > > returns tile zero, while residency returns average. > > > > As the interface is done now, the rc6_enable is just returning > > whether the gpu (i.e. i915, not gt) supports RC6 or not. I think > > there is a patch later. > > > > > Even the deprecated message gets logged with every access right? > > > > > > Btw is the deperecated message limited to multi-tile platforms (can't see > > > that it is) and what is the plan for that? > > > > yes, at this point the message would need to be removed and I > > forgot to do it. > > Maybe it is correct to have it, I don't know at this point. Is the plan to > remove the warning everywhere, or only have it on multi-tile platforms, or > new platforms? And/or remove legacy files after a while on all platforms, or > just new ones? At this point I guess the warning should be removed from everywhere (i.e. only those RC6 and RPS interfaces that are duplicated/multiplexed). We shouldn't be supposed to need more usage of multiplexed interfaces in the future (maybe just rc6 enable, but I don't see it really necessary). Thanks, Andi