From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6085623D7D3; Wed, 13 Aug 2025 10:15:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755080145; cv=none; b=Xd1LuKAXTPBMAqwbU9jOE+DmKu4pwv6fUHmTZiy63CXoMHhOBNA/28Eq6F5o9y8pQHk+nP4P0HqobXexXYBCWhRm3Mxz5/bllF/CRHZtnyYcFpD81GxN++4HlEWHmLVAuA1TBbNOcbjxtg4J/2qvF+1SS5/eu5ueq2NwnjbdUQo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755080145; c=relaxed/simple; bh=ZluH6uhX2B/02Winvt1DG5yfLXuMX01kxN6jfx2fzOE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=t/GOcw6igeXMJ594cYKnvNBoHxL/H3SZMzbQks7F8dDKOAQkNPyAJ/QcVYH8Q4vBlff4Yxvc/zFgCucov3PA72IyiIGox9dDhUnYByxwCvY7S9qeozU84my+G7M6enqO2Sf/SIb1YvzEhs8RKfL5ilAzqu/gTo5DL9T93eXQvOw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 8C21B12FC; Wed, 13 Aug 2025 03:15:35 -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 D59D93F5A1; Wed, 13 Aug 2025 03:15:39 -0700 (PDT) Date: Wed, 13 Aug 2025 12:15:24 +0200 From: Beata Michalska To: Prashant Malani Cc: Viresh Kumar , "Rafael J. Wysocki" , Jie Zhan , Ionela Voinescu , Ben Segall , Dietmar Eggemann , Ingo Molnar , Juri Lelli , open list , "open list:CPU FREQUENCY SCALING FRAMEWORK" , Mel Gorman , Peter Zijlstra , Steven Rostedt , Valentin Schneider , Vincent Guittot , z00813676 , sudeep.holla@arm.com Subject: Re: [PATCH v2 2/2] cpufreq: CPPC: Dont read counters for idle CPUs Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Aug 08, 2025 at 02:14:39AM +0000, Prashant Malani wrote: > Hi Beata, > > On Aug 07 12:24, Beata Michalska wrote: > > Right .... that's what happens when you are (I am) making last minute clean up. > > That should fix it. Would you mind giving it another go ? Would appreciate it. > > > > --- > > BR > > Beata > > > > diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c > > index 65adb78a9a87..2a51e93fcd6c 100644 > > --- a/arch/arm64/kernel/topology.c > > +++ b/arch/arm64/kernel/topology.c > > @@ -543,7 +543,7 @@ void counters_burst_read_on_cpu(void *arg) > > > > static inline bool cpc_reg_supported(struct cpc_reg *reg) > > { > > - return !((u64)reg->address != 0x0 || (u64)reg->address != 0x1); > > + return !((u64)reg->address != 0x0 && (u64)reg->address != 0x1); > > } > > Here are the measurements with the fix: > > The readings are less accurate. There are some which report > 3.4 GHz (as earlier) but many are off: > > t0: del:77500009084, ref:22804739600 > t1: del:77500020316, ref:22804743100 > ref_perf:10 > delivered_perf:32 > > t0: del:77910203848, ref:22941794740 > t1: del:77910215594, ref:22941798070 > ref_perf:10 > delivered_perf:35 > > t0: del:77354782419, ref:22762276000 > t1: del:77354793991, ref:22762279400 > ref_perf:10 > delivered_perf:34 > > t0: del:64470686034, ref:22998377620 > t1: del:64470695313, ref:22998380880 > ref_perf:10 > delivered_perf:28 > > t0: del:78019898424, ref:22957940640 > t1: del:78019912872, ref:22957944590 > ref_perf:10 > delivered_perf:36 > > Best regards, > > -Prashant Ok, that's not really good. Any chances on sharing which platform are you using ? Remote debugging tends to be rather painful. --- (Note: I will be off for couple of days so please bear with me) BR Beata