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 6C711C7EE22 for ; Wed, 10 May 2023 06:02:06 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B72D410E2A2; Wed, 10 May 2023 06:02:05 +0000 (UTC) Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2B9D110E2A2 for ; Wed, 10 May 2023 06:02:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1683698523; x=1715234523; h=date:message-id:from:to:cc:subject:in-reply-to: references:mime-version; bh=y4jHm1h11fWOHDFr4tNYzfkYMUYea6Fs4OtcvcN1sus=; b=PKR3+696jeyIF7O87I/Ut3XjXZNcxIKSQi764qtcUc9buwz4x0eXe8hZ 0Ws86JhWWPLb1w/0Cz5Eabt/LBiyuEBnKGq8aWIQnqyAwTqj5y4EoNRV2 f1JdbBKf/bNa50W8hmQKrIKmP/VJrBo1RYpQUPmLsAsikDDV/w78Gp4Jy yvqbLcOk7xU05H1rqWxCiDEwbbM9/lq4HOBtRlE8NM0OscmMI7nlT0SvS b/2vh4Uf5Ex3k4f8uYANvI9yGCKesctABvrUzeFnEZfdt9nEi2cqRViie eqGEkNcSYN/FUhh2JLBX7Tt7wGPS6lESBPcYHf3QuCs3M2Ig9Vf5ioovc Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10705"; a="413426295" X-IronPort-AV: E=Sophos;i="5.99,263,1677571200"; d="scan'208";a="413426295" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 May 2023 23:02:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10705"; a="823422065" X-IronPort-AV: E=Sophos;i="5.99,263,1677571200"; d="scan'208";a="823422065" Received: from adixit-mobl.amr.corp.intel.com (HELO adixit-arch.intel.com) ([10.255.228.213]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 May 2023 23:02:01 -0700 Date: Tue, 09 May 2023 23:02:01 -0700 Message-ID: <871qjog1wm.wl-ashutosh.dixit@intel.com> From: "Dixit, Ashutosh" To: Umesh Nerlige Ramappa In-Reply-To: <87bkitxvr7.wl-ashutosh.dixit@intel.com> References: <20230506005816.1891043-1-umesh.nerlige.ramappa@intel.com> <20230506005816.1891043-5-umesh.nerlige.ramappa@intel.com> <87bkitxvr7.wl-ashutosh.dixit@intel.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?ISO-8859-4?Q?Goj=F2?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/28.2 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII Subject: Re: [Intel-gfx] [PATCH 4/6] drm/i915/pmu: Add reference counting to the sampling timer 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 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, 09 May 2023 10:25:16 -0700, Dixit, Ashutosh wrote: > > On Fri, 05 May 2023 17:58:14 -0700, Umesh Nerlige Ramappa wrote: > > > > From: Tvrtko Ursulin > > > > We do not want to have timers per tile and waste CPU cycles and energy via > > multiple wake-up sources, for a relatively un-important task of PMU > > sampling, so keeping a single timer works well. But we also do not want > > the first GT which goes idle to turn off the timer. > > Apart from this efficiency, what is the reason for having a device level > PMU (which monitors gt level events), rather than independent gt level > PMU's (each of which monitor events from that gt)? > > Wouldn't independent gt level PMU's be simpler? And user space tools (say > intel-gpu-top) would hook into events from a gt and treat each gt > independently? > > So my question really is what is the reason for keeping the PMU device > level rather than per gt? Maybe ignore this for now, the way it is expressed it is too open ended. Let me get a better handle on the code and the patches and I'll see if I have anything to say. Thanks. -- Ashutosh