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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F113EEB56E for ; Fri, 8 Sep 2023 22:08:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241600AbjIHWIa (ORCPT ); Fri, 8 Sep 2023 18:08:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232557AbjIHWI3 (ORCPT ); Fri, 8 Sep 2023 18:08:29 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D7B31FCA; Fri, 8 Sep 2023 15:08:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=feIhy29eviQcz3w0j03WPUHi04Iv5MnRQxdFAPqyNns=; b=iGdC1B3qg4fADH5R3wqKQoYmDG ieN/d/cOMcuLZxa8xFAqYA43F7gzyHMFHAr/TtBRQy1zqrRV7y+tOxipUaS1Ma6Yb5A8HAIlrXfmZ yePoLRILXBzhIdDE3aWtRp4ns02dIS020WLLwEJ7aiohM6PyZ/krE/N1GOOU8hQDA4NW23kc+bXjd xw913cMBdeCNxf9E6ARB4+m94PAdRNrlcAskL7zas1Eqk6h5HK6faYQcSEMqYkQs0H427ECZMyY1n W7DHkhGlV3YuT9Lngbbv3uV9IiD8WDDNjrQPYJTGwy7saFAKw97D2fRHtH39kY0SebqOXHTq5Fsqc HIIkmNdQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qejdz-002mtY-0x; Fri, 08 Sep 2023 22:08:09 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 621F73005FA; Sat, 9 Sep 2023 00:08:04 +0200 (CEST) Date: Sat, 9 Sep 2023 00:08:04 +0200 From: Peter Zijlstra To: Elliot Berman Cc: Ingo Molnar , "Rafael J. Wysocki" , Pavel Machek , Thomas Gleixner , kernel@quicinc.com, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Prakash Viswalingam Subject: Re: [PATCH v2] freezer,sched: Use saved_state to reduce some spurious wakeups Message-ID: <20230908220804.GA29218@noisy.programming.kicks-ass.net> References: <20230830-avoid-spurious-freezer-wakeups-v2-1-8877245cdbdc@quicinc.com> <20230904212324.GA2568@noisy.programming.kicks-ass.net> <20230907094651.GB16872@noisy.programming.kicks-ass.net> <4c5b5a0b-6d78-878e-7e66-e08e83e6e1c8@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4c5b5a0b-6d78-878e-7e66-e08e83e6e1c8@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 08, 2023 at 01:08:07PM -0700, Elliot Berman wrote: > > Perhaps we should start off by doing the below, instead of making it > > more complicated instead. I suppose you're right about the overhead, but > > run a hackbench just to make sure or something. > > > > I ran perf bench sched message -g 40 -l 40 with the v3 patch [1]. After 60 > iterations each, I don't see a significant difference on my arm64 platform: > both samples ~normal and ~eq variance w/t-test p-value: 0.79. > > We also ran typical high level benchmarks for our SoCs (antutu, > geekbench, et. al) and didn't see any regressions there. So if you would've made this 2 patches, the first removing the ifdef, then the changelog for that patch would be a good place to mention it doesn't measurably regress things. As a bonus, it then makes your other changes smaller too ;-)