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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 767FCC43381 for ; Tue, 5 Mar 2019 11:13:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 425212082C for ; Tue, 5 Mar 2019 11:13:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="RtrKpLm8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 425212082C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mVTIXqGPzeh6yW7k9LYubyyB1ZFmvW2GY2RLP3yeNgw=; b=RtrKpLm8+CePwu OOme0qi5vfo4Q4hbIPHlzNnYE35m1D74tgaFz3hAGjwHhR6DVj4cG1FpqyuTqeASxT+M+cDpgxKBM 1DuSHPnUnMDo6AZg7uvq87dgyugG+7Wj9/epdsWJK4xee95hI2056bY0k5RW4BMilNevxWKfSobuD XJ5zMBrzA6BOaBwoGyMPt7Ui1x7T+gx+SbaHuk1F1FpZWhgKvYlJWmSMzz1J16PrcTRQrbvZVrLeg IPZmraPS3WRIey/624zkO+0qHAZg1v2GVxWwfSJ3kx/f0n5KOk8b6UzGuyria31Ivp19gmKVHNBaA IE6RS6AURvM5lJgzKR7g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h180r-0002JC-Qm; Tue, 05 Mar 2019 11:13:33 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h180o-0002Fh-Sb for linux-arm-kernel@lists.infradead.org; Tue, 05 Mar 2019 11:13:32 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5E71DA78; Tue, 5 Mar 2019 03:13:28 -0800 (PST) Received: from e107155-lin (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B5DC03F71D; Tue, 5 Mar 2019 03:13:26 -0800 (PST) Date: Tue, 5 Mar 2019 11:13:21 +0000 From: Sudeep Holla To: Quentin Perret Subject: Re: [PATCH] arch_topology: Update user supplied capacity to possible cpus in cluster Message-ID: <20190305111321.GA5458@e107155-lin> References: <1551354838-29902-1-git-send-email-clingutla@codeaurora.org> <20190228121901.GA26207@e107155-lin> <6d7eb7cc-2453-3a7b-9163-ef9a5389220f@codeaurora.org> <20190228152555.GA13165@e107155-lin> <5785fd91-3d76-78e6-f4c5-7ed07be1a14d@codeaurora.org> <20190304182138.GA7553@e107155-lin> <20190305092322.q7odi3inofnvzhre@queper01-lin> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190305092322.q7odi3inofnvzhre@queper01-lin> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190305_031330_926334_5F9DACD2 X-CRM114-Status: GOOD ( 21.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Chandra Sekhar Lingutla , catalin.marinas@arm.com, will.deacon@arm.com, Jeremy Linton , Morten Rasmussen , Sudeep Holla , dietmar.eggemann@arm.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Mar 05, 2019 at 09:23:25AM +0000, Quentin Perret wrote: > On Monday 04 Mar 2019 at 18:21:38 (+0000), Sudeep Holla wrote: > > On Sat, Mar 02, 2019 at 07:00:43PM +0530, Chandra Sekhar Lingutla wrote: > > > So cpus in cpu_topology->core_sibling mask would not need to have same > > > capacity_cpu ? > > > > Yes, it need not. DSU is simple example. Even normal heterogeneous > > multi-cluster single socket systems will have all the cpus in the die > > present in core_siblings. > > > > > Then i think, we should update the cpu_capacity for only requested cpu > > > right? > > > > One possible solution and a simpler one. But I am open to any better > > alternative if it exists/possible. > > How about we update the capacity for the related_cpus of the CPUFreq > policy ? This is what we're interested in here, I think, and is > orthogonal to the topology stuff. And that should map fairly well to the > core_sibling_mask for legacy platforms. > While I like the idea, I am afraid that linking this to cpufreq policy may not be good. How will we deal with it on systems without CPUfreq ? > FWIW, we already mandate something similar for EAS for example > (see [1]), and I'm not sure we want to support having different uarchs > in the same freq domain here either, even though strictly speaking > DynamIQ doesn't forbid it. > Yes that dependency is other way around and topology is not optional, so it works out well. The reverse may not be that simple. > [1] https://elixir.bootlin.com/linux/latest/source/kernel/power/energy_model.c#L170 > > [...] > > > I was always under the impression that this was in debugfs and will be > > removed. I did mention this in one of the thread couple of months back. > > I was wrong and do understand the need for this on system where firmware > > doesn't provide this capacity value. > > > > If possible I want to drop the write capability for the sysfs. > > But yes, that is even better, if at all possible. > I think if there are no valid users of this, we *must* remove it. As I have pointed out in past, giving user such access will need platform knowledge. Though it's debatable topic, firmware providing this information is the only correct solution IMO. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel