From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: Re: [PATCH v3] ACPI / Processor: add sysfs support for low power idle Date: Wed, 15 Nov 2017 18:14:05 +0000 Message-ID: References: <1508437188-14463-1-git-send-email-pprakash@codeaurora.org> <0569bb96-bd27-6c01-eb3c-5e4e1d868b2a@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from foss.arm.com ([217.140.101.70]:43244 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758043AbdKOSOJ (ORCPT ); Wed, 15 Nov 2017 13:14:09 -0500 In-Reply-To: Content-Language: en-US Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Timur Tabi Cc: Sudeep Holla , Prashanth Prakash , ACPI Devel Maling List , "Rafael J. Wysocki" , Lorenzo Pieralisi , Len Brown On 15/11/17 15:33, Timur Tabi wrote: > On Wed, Nov 8, 2017 at 8:18 AM, Sudeep Holla wrote: >> I still prefer this as debugfs and not as sysfs ABI. We already have >> issues with multiple interfaces for the same thing. E.g. cpufreq on x86. >> I don't want this to end up in the same way after few years. CPUIdle >> sysfs should be only sysfs ABI for these, adding an alternative is >> inviting troubles for future especially if some user-space starts using >> it and we will be stuck with that. Moreover with more h/w controlled >> idle we may not provide accurate data sooner. >> >> Sorry for the noise, I will shup up now ;). Since this may be last >> chance to make some noise, I am trying it. I completely understand that >> this is just my opinion and am fine if others thinks it's good to make >> this sysfs ABI. > > Unfortunately, I think Prashanth really needs a specific requirement > rather than opinions. I completely understand that. So for I haven't got a solid reason as why debugfs is not sufficient? If it becomes so popular in future, we can discuss and then make it sysfs ABI with more thoughts/discussions. > This patch has been languishing for over a month, and we still have > no idea whether it will make 4.15 or if Prashanth is *required* to > make any more changes. > It's sysfs ABI which we need to support for very long time(not in months but in years), so waiting/discussing for couple of months is much safer than spending more time to keep it the sysfs ABI unbroken. Also I assume(was explicitly mentioned IIRC) that it's purely used for debug and tuning purposes and hence I see *no need* to be part of *sysfs ABI*. Let me know if the circumstances have changed. -- Regards, Sudeep