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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 7EFCCC43387 for ; Tue, 8 Jan 2019 18:49:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5050D20827 for ; Tue, 8 Jan 2019 18:49:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Uu/7bonv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729473AbfAHStl (ORCPT ); Tue, 8 Jan 2019 13:49:41 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:50400 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727829AbfAHStl (ORCPT ); Tue, 8 Jan 2019 13:49:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=9EThvUedqwr9JLagw4SbqAFedU0AoJZ9CKdWwl7XKiA=; b=Uu/7bonv5ZaHGzI6QLfILzH9B puh54QM8wm3H7+zKWLUgPsli0zU7U2sj4ZY8gDz+g1tyBdF4Xo6U6eBGsKezYjvqnhIBZKNtC228Z mjGzNwbI/ic4qkyDTUSUrAuciBBzKhhlVnTGc/zIxj0ggVaOxfZAC9/mj6UxvDOOEQiDr3Y2xFdlK snYv0/ZvaVrjGUtmfBj9ak+edbZ/9hi+/jApT37OBk9WJn5519c4gTVbS68ifn97QoyRIfmadth1K Q8Y71bcS4buqpXGjXg8wnzbUs5DiONR9amO94TYHZn8ZEPRLlJxCgRPR/W8Ia9sI5WEQTS2cfzNgX z2sT6TyHg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1ggwQw-0007W7-MF; Tue, 08 Jan 2019 18:49:02 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 1C99320289CC1; Tue, 8 Jan 2019 19:49:01 +0100 (CET) Date: Tue, 8 Jan 2019 19:49:01 +0100 From: Peter Zijlstra To: Boris Ostrovsky Cc: Andrew Murray , Ingo Molnar , Arnaldo Carvalho de Melo , Richard Henderson , Ivan Kokshaysky , Matt Turner , Will Deacon , Mark Rutland , Shawn Guo , Sascha Hauer , Benjamin Herrenschmidt , Paul Mackerras , Thomas Gleixner , Borislav Petkov , Russell King , suzuki.poulose@arm.com, robin.murphy@arm.com, Michael Ellerman , x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, jgross@suse.com Subject: Re: [PATCH v4 10/13] x86: perf/core: use PERF_PMU_CAP_NO_EXCLUDE for exclude incapable PMUs Message-ID: <20190108184901.GA1900@hirez.programming.kicks-ass.net> References: <1546878450-20341-1-git-send-email-andrew.murray@arm.com> <1546878450-20341-11-git-send-email-andrew.murray@arm.com> <20190108104841.GD6808@hirez.programming.kicks-ass.net> <7300f0af-b532-5546-a6f4-fec69cb91a0f@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7300f0af-b532-5546-a6f4-fec69cb91a0f@oracle.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 08, 2019 at 11:36:33AM -0500, Boris Ostrovsky wrote: > On 1/8/19 5:48 AM, Peter Zijlstra wrote: > > On the various exclude options; they are as follows (IIUC): > > > > - exclude_guest: we're a HV/host-kernel and we don't want the counter > > to run when we run a guest context. > > > > - exclude_host: we're a HV/host-kernel and we don't want the counter > > to run when we run in host context. > > > > - exclude_hv: we're a guest and don't want the counter to run in HV > > context. > > > > Now, KVM always implies exclude_hv afaict (for guests), I'm not sure > > what, if anything Xen does on x86 (IIRC Brendan Gregg once said perf > > works on Xen) -- nor quite sure who to ask, Boris, Jeurgen? > > perf does work inside guests. > > VPMU is managed by the Xen and it presents to the guest only samples > that are associated with the guest. So from that perspective exclude_hv > doesn't seem to be needed. > > There is a VPMU mode that allows profiling whole system (host and > guests) from dom0, and this where exclude_hv might be useful. But this > mode, ahem, needs some work. Thanks Boris!