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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 553F1C3DA42 for ; Wed, 17 Jul 2024 06:59:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oo7llmzmqoFWiQrXmRwaRKXUfI5DmUunmiZgoNVLAdc=; b=JWwSEQq3ERQhUvI2+bzIYLvyM4 jZ8MZwa4LBiilVVCP3TA0K4Qnjor1a5n8D57LAIZfj0DG5kwnYzevTfU4oltMaq/Te/aG3ikwkIo6 SGuEkRSICro6X60yZJQ7d/tmH5fDe4d9yQh//iwg0Ebr7pIyGO2HGOdzmHglwUrYSEoCF5O6AIKsL vGyE+lXPvF4PzHezbo/JfzqEh6R98ebQ2B122zOmbHDhsrPKgwC4afv6y6ox6FCv5xCYy4ZpP6gM0 5qVU0RUpy/KzITHWl1d+2td6FW68stxfV3oeksglSHla+SzQ8bVsCjGH2bwkN6rt6s9qUhfrDdxFU t34PhC8Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sTycy-0000000Cuya-3IWj; Wed, 17 Jul 2024 06:59:04 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sTycd-0000000Cuv3-2JA0 for linux-arm-kernel@lists.infradead.org; Wed, 17 Jul 2024 06:58:45 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DD02F1063; Tue, 16 Jul 2024 23:59:06 -0700 (PDT) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8C5383F762; Tue, 16 Jul 2024 23:58:38 -0700 (PDT) Date: Wed, 17 Jul 2024 08:58:28 +0200 From: Beata Michalska To: Vanshidhar Konda Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, ionela.voinescu@arm.com, sudeep.holla@arm.com, will@kernel.org, catalin.marinas@arm.com, vincent.guittot@linaro.org, sumitg@nvidia.com, yang@os.amperecomputing.com, lihuisong@huawei.com, viresh.kumar@linaro.org, rafael@kernel.org Subject: Re: [PATCH v6 0/4] Add support for AArch64 AMUv1-based arch_freq_get_on_cpu Message-ID: References: <20240603082154.3830591-1-beata.michalska@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240716_235843_715426_6A97E020 X-CRM114-Status: GOOD ( 29.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, Jul 13, 2024 at 05:32:43PM -0700, Vanshidhar Konda wrote: > On Mon, Jun 03, 2024 at 09:21:50AM +0100, Beata Michalska wrote: > > Introducing arm64 specific version of arch_freq_get_on_cpu, cashing on > > existing implementation for FIE and AMUv1 support: the frequency scale > > factor, updated on each sched tick, serves as a base for retrieving > > the frequency for a given CPU, representing an average frequency > > reported between the ticks - thus its accuracy is limited. > > > > The changes have been rather lightly (due to some limitations) tested on > > an FVP model. Note that some small discrepancies have been observed while > > I've tested these changes (v6) on AmpereOne system and the results look correct. > The frequency reported by scaling_cur_freq is as expected for housekeeping cpus, > idle as well as isolated cpus. > That's greatly appreciated - thank you for that! This series depends on [1] so once the relevant changes are ready will send an updated to expose the average freq through a relevant sysfs attrib. --- [1] https://lore.kernel.org/all/ZmrB_DqtmVpvG30l@arm.com/ --- Best Regards Beata > Thanks, > Vanshi > > > testing (on the model) and this is currently being investigated, though it > > should not have any significant impact on the overall results. > > > > Relevant discussions: > > [1] https://lore.kernel.org/all/20240229162520.970986-1-vanshikonda@os.amperecomputing.com/ > > [2] https://lore.kernel.org/all/7eozim2xnepacnnkzxlbx34hib4otycnbn4dqymfziqou5lw5u@5xzpv3t7sxo3/ > > [3] https://lore.kernel.org/all/20231212072617.14756-1-lihuisong@huawei.com/ > > [4] https://lore.kernel.org/lkml/ZIHpd6unkOtYVEqP@e120325.cambridge.arm.com/T/#m4e74cb5a0aaa353c60fedc6cfb95ab7a6e381e3c > > > > v6: > > - delay allocating cpumask for AMU FIE support instead of invalidating the mask > > upon failure to register cpufreq policy notifications > > - drop the change to cpufreq core (for cpuinfo_cur_freq) as this one will be > > sent as a separate change > > > > v5: > > - Fix invalid access to cpumask > > - Reworked finding reference cpu when getting the freq > > > > v4: > > - dropping seqcount > > - fixing identifying active cpu within given policy > > - skipping full dynticks cpus when retrieving the freq > > - bringing back plugging in arch_freq_get_on_cpu into cpuinfo_cur_freq > > > > v3: > > - dropping changes to cpufreq_verify_current_freq > > - pulling in changes from Ionela initializing capacity_freq_ref to 0 > > (thanks for that!) and applying suggestions made by her during last review: > > - switching to arch_scale_freq_capacity and arch_scale_freq_ref when > > reversing freq scale factor computation > > - swapping shift with multiplication > > - adding time limit for considering last scale update as valid > > - updating frequency scale factor upon entering idle > > > > v2: > > - Splitting the patches > > - Adding comment for full dyntick mode > > - Plugging arch_freq_get_on_cpu into cpufreq_verify_current_freq instead > > of in show_cpuinfo_cur_freq to allow the framework to stay more in sync > > with potential freq changes > > > > > > > > Beata Michalska (3): > > arm64: amu: Delay allocating cpumask for AMU FIE support > > arm64: Provide an AMU-based version of arch_freq_get_on_cpu > > arm64: Update AMU-based frequency scale factor on entering idle > > > > Ionela Voinescu (1): > > arch_topology: init capacity_freq_ref to 0 > > > > arch/arm64/kernel/topology.c | 145 +++++++++++++++++++++++++++++------ > > drivers/base/arch_topology.c | 8 +- > > 2 files changed, 127 insertions(+), 26 deletions(-) > > > > -- > > 2.25.1 > >