From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 0/5] Add power feature debugfs disabling Date: Tue, 4 Feb 2014 12:30:00 +0100 Message-ID: <20140204113000.GN17001@phenom.ffwll.local> References: <1391204572-18888-1-git-send-email-jeff.mcgee@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ee0-f41.google.com (mail-ee0-f41.google.com [74.125.83.41]) by gabe.freedesktop.org (Postfix) with ESMTP id 41588105891 for ; Tue, 4 Feb 2014 03:30:07 -0800 (PST) Received: by mail-ee0-f41.google.com with SMTP id e51so2050695eek.28 for ; Tue, 04 Feb 2014 03:30:05 -0800 (PST) Content-Disposition: inline In-Reply-To: <1391204572-18888-1-git-send-email-jeff.mcgee@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: jeff.mcgee@intel.com Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Fri, Jan 31, 2014 at 03:42:47PM -0600, jeff.mcgee@intel.com wrote: > From: Jeff McGee > > This series has recently been accepted into the Haswell Android kernel and > helps with debugging and profiling these power features. I would like it > to be considered for upstream incorporation. The patches here have been > rebased (minimal changes required) and compile-tested only. > > Broad device support is provided, accept for RPS and RC6 with Broadwell > and Valleyview. Both of these were somewhat of a moving target and I > didn't have devices to work with. Support can of course be added with > help from appropriate folks. > > The hooks introduce some amount of overhead as an additional check is > often needed to determine whether the feature is on or off - similar to > the module parameters that already exist. I felt that the overhead was > minimal enough and didn't want to ugly up the code with CONFIG_DEBUG_FS > compile conditionals. But I'm open to the list's thoughts on this. > > IGT tests of these new interfaces can certainly be added. I wanted to > make sure there was sufficient interest in having these interfaces before > starting on the tests. So please provide feedback. debugfs doesn't have any abi guarantees and hence requirements are much lower. Generally I only want a testcase for new debugfs if it is complex infrastructure and other testcases rely on its functionality, like the CRC stuff. Simple on/off knobs imo don't need testcases really. Still even debugfs code has a bit of cost, so I'll hold off until someone says that "yep, this is useful for developing stuff, I'll review it" or some i-g-ts show up. Cheers, Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch