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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 3712A409DD; Mon, 12 Jul 2021 12:02:53 -0400 (EDT) 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 MvADQZakXO5u; Mon, 12 Jul 2021 12:02:51 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id BC1AE40799; Mon, 12 Jul 2021 12:02:51 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id ED4BE4066E for ; Mon, 12 Jul 2021 12:02:50 -0400 (EDT) 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 j1XLOH7cNEG5 for ; Mon, 12 Jul 2021 12:02:49 -0400 (EDT) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 70FBD40617 for ; Mon, 12 Jul 2021 12:02:49 -0400 (EDT) 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 1A6E11FB; Mon, 12 Jul 2021 09:02:49 -0700 (PDT) Received: from [10.57.36.240] (unknown [10.57.36.240]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6C4933F774; Mon, 12 Jul 2021 09:02:47 -0700 (PDT) Subject: Re: [PATCH v2] KVM: arm64: Disabling disabled PMU counters wastes a lot of time To: Alexandru Elisei , Alexandre Chartre , maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, james.morse@arm.com, suzuki.poulose@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org References: <20210712151700.654819-1-alexandre.chartre@oracle.com> <90b0b99b-505c-c46c-6c2c-a45192135f5a@arm.com> From: Robin Murphy Message-ID: <74ccea1f-50b6-cf10-0b7f-3aced1d6f42e@arm.com> Date: Mon, 12 Jul 2021 17:02:43 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <90b0b99b-505c-c46c-6c2c-a45192135f5a@arm.com> Content-Language: en-GB Cc: konrad.wilk@oracle.com 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: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu T24gMjAyMS0wNy0xMiAxNjo1MSwgQWxleGFuZHJ1IEVsaXNlaSB3cm90ZToKPiBIaSBSb2JpbiwK PiAKPiBPbiA3LzEyLzIxIDQ6NDQgUE0sIFJvYmluIE11cnBoeSB3cm90ZToKPj4gT24gMjAyMS0w Ny0xMiAxNjoxNywgQWxleGFuZHJlIENoYXJ0cmUgd3JvdGU6Cj4+PiBJbiBhIEtWTSBndWVzdCBv biBhcm02NCwgcGVyZm9ybWFuY2UgY291bnRlcnMgaW50ZXJydXB0cyBoYXZlIGFuCj4+PiB1bm5l 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