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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 B4CDCC43603 for ; Wed, 11 Dec 2019 17:28:59 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 7AE29208C3 for ; Wed, 11 Dec 2019 17:28:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7AE29208C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 177324ACFA; Wed, 11 Dec 2019 12:28:59 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id uJUOZiH4pnw0; Wed, 11 Dec 2019 12:28:58 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 12FAE4ACF2; Wed, 11 Dec 2019 12:28:58 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 429874ACF2 for ; Wed, 11 Dec 2019 12:28:57 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id g1Vo8KuAHdpe for ; Wed, 11 Dec 2019 12:28:56 -0500 (EST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4C51C4ACC9 for ; Wed, 11 Dec 2019 12:28:56 -0500 (EST) 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 00E4730E; Wed, 11 Dec 2019 09:28:56 -0800 (PST) Received: from [10.1.197.1] (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 19A543F52E; Wed, 11 Dec 2019 09:28:54 -0800 (PST) Subject: Re: [PATCH v2 3/3] arm64: perf: Add support for ARMv8.5-PMU 64-bit counters To: Andrew Murray , Catalin Marinas , Will Deacon , Marc Zyngier , Mark Rutland References: <20191210120146.2942-1-andrew.murray@arm.com> <20191210120146.2942-4-andrew.murray@arm.com> From: Suzuki Kuruppassery Poulose Message-ID: <314c8b5e-5f12-63f9-0937-602450db70b2@arm.com> Date: Wed, 11 Dec 2019 17:28:54 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191210120146.2942-4-andrew.murray@arm.com> Content-Language: en-US Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On 10/12/2019 12:01, Andrew Murray wrote: > At present ARMv8 event counters are limited to 32-bits, though by > using the CHAIN event it's possible to combine adjacent counters to > achieve 64-bits. The perf config1:0 bit can be set to use such a > configuration. > > With the introduction of ARMv8.5-PMU support, all event counters can > now be used as 64-bit counters. > > Let's enable 64-bit event counters where support exists. Unless the > user sets config1:0 we will adjust the counter value such that it > overflows upon 32-bit overflow. This follows the same behaviour as > the cycle counter which has always been (and remains) 64-bits. > > Signed-off-by: Andrew Murray Reviewed-by: Suzuki K Poulose _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm