From patchwork Tue Feb 18 19:24:12 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beata Michalska X-Patchwork-Id: 13980783 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 5D678C021AA for ; Tue, 18 Feb 2025 20:08:20 +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:Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=gZ5/DhQkh566/EMv7++F1qfmxIqjW97yewkOSacP61c=; b=RWj30pZmbmWaQl7I7MDrGq7Rqh 8atw+dxXkKUDZvZwk/XVdYVRAaUnrDBPh0fnzRDVxMjAhMugzvLFqlgmySsBphG+XXaKCbUYUuPU6 JkLCctG7Yplwqw3MZV6+7jQ3J6UiIWSjSsQQMK+IOQSXKPAYM+LAbIImwW2uXBWf0IkXMDlxOyHYS yMy4dJJSKKJjE+i+/oguB2r30HBAsAoGd3uONRIFa48tfIT6Nyiryu+Z2L7t/BgLWr4aVB14BvHe6 07YXtX/qrh4rdyY0zE8Ejn4UiQ3p/q7A/ffAuAJm9gLpVWORo61W93f4z/kq1vDEE9uRIKJZXH+ZB 7nYNvyyg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tkTt5-00000009hLC-2JHF; Tue, 18 Feb 2025 20:08:11 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tkTCz-00000009YkO-3aIk for linux-arm-kernel@lists.infradead.org; Tue, 18 Feb 2025 19:24:43 +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 91CC9152B; Tue, 18 Feb 2025 11:24:59 -0800 (PST) Received: from e125905.cambridge.arm.com (e125905.cambridge.arm.com [10.1.194.73]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B07CD3F6A8; Tue, 18 Feb 2025 11:24:38 -0800 (PST) From: Beata Michalska To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com, will@kernel.org, catalin.marinas@arm.com, sfr@canb.auug.org.au Cc: ionela.voinescu@arm.com, yury.norov@gmail.com, linux-next@vger.kernel.org, sumitg@nvidia.com, yang@os.amperecomputing.com, vanshikonda@os.amperecomputing.com, lihuisong@huawei.com, zhanjie9@hisilicon.com, ptsm@linux.microsoft.com Subject: [PATCH] arm64: Utilize for_each_cpu_wrap for reference lookup Date: Tue, 18 Feb 2025 19:24:12 +0000 Message-Id: <20250218192412.2072619-1-beata.michalska@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250218_112441_935491_9BE46EFD X-CRM114-Status: UNSURE ( 9.24 ) X-CRM114-Notice: Please train this message. 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 While searching for a reference CPU within a given policy, arch_freq_get_on_cpu relies on cpumask_next_wrap to iterate over all available CPUs and to ensure each is verified only once. Recent changes to cpumask_next_wrap will handle the latter no more, so switching to for_each_cpu_wrap, which preserves expected behavior while ensuring compatibility with the updates. Fixes: 16d1e27475f6 ("arm64: Provide an AMU-based version of arch_freq_get_on_cpu") Signed-off-by: Beata Michalska --- based on arm64 for-next/amuv1-avg-freq arch/arm64/kernel/topology.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index a09b0551ec59..9e3583720668 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -254,7 +254,7 @@ int arch_freq_get_on_cpu(int cpu) if (!housekeeping_cpu(cpu, HK_TYPE_TICK) || time_is_before_jiffies(last_update + msecs_to_jiffies(AMU_SAMPLE_EXP_MS))) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - int ref_cpu = cpu; + int ref_cpu; if (!policy) return -EINVAL; @@ -265,11 +265,15 @@ int arch_freq_get_on_cpu(int cpu) return -EOPNOTSUPP; } - do { - ref_cpu = cpumask_next_wrap(ref_cpu, policy->cpus, - start_cpu, true); - - } while (ref_cpu < nr_cpu_ids && idle_cpu(ref_cpu)); + for_each_cpu_wrap(ref_cpu, policy->cpus, cpu + 1) { + if (ref_cpu == start_cpu) { + /* Prevent verifying same CPU twice */ + ref_cpu = nr_cpu_ids; + break; + } + if (!idle_cpu(ref_cpu)) + break; + } cpufreq_cpu_put(policy);