From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-188.mta1.migadu.com (out-188.mta1.migadu.com [95.215.58.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78C53209681 for ; Wed, 6 Nov 2024 19:53:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730922810; cv=none; b=mwm+xpL29y1fcJGlm+GQ0hIdH88SJHWwEfFKrf5yXbaVAb/1pFEY4yVdBgle9g+GhDQiD0AXfKLD8+N72wl6EAXBR7+/XfiVYqHZIi3EtMNDkfkfgEtnfwmI5cA122/JBqVlLWyv1J7DLMRMAQY+YL22oSHJrWMWLgrIu1URCJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730922810; c=relaxed/simple; bh=46vNwXHJt3VTkoNVKvyUOMEbBuMcyNhib1Czm9V81qg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ry1BOGUgw1B/29CzGJ5riJtPASTEmedCx9d+8Y6nuAQWc/TnQXLUk+5SJ7Qv0r8CrloKL0CcddL3FjbsP3i9oX+ngI75OafdoPUDibet+mzddYmkDHhKDZkxvmSTGSqxIat2rGOVw1C2KnyVy9hiXP9jDrUPPAQ9j5K1JDntQAQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=azPQPKMc; arc=none smtp.client-ip=95.215.58.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="azPQPKMc" Date: Wed, 6 Nov 2024 11:53:07 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1730922800; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=uIYHrYeDhg7kNxYUdjNDrUK44gnqtUzRYj+2b/H+nmQ=; b=azPQPKMcRZ7n0haevtf+gW2LUqUgNTZ0txSbzF62ESJFFuZ5O81yldkwxJtbt9eMJ9rYhP N+C8TyY7NMWCBJoFUX2fQEo2lLIcOBBEbEAiDRA7VK/RvAEm4WY0TpFGNaZYNkz2wLfxEo 3CDxbqePxlmasgDPRU9wm5HtPnrmBuo= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: "Liang, Kan" Cc: Colton Lewis , kvm@vger.kernel.org, Sean Christopherson , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Will Deacon , Russell King , Catalin Marinas , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org Subject: Re: [PATCH v6 5/5] perf: Correct perf sampling with guest VMs Message-ID: References: <20241105195603.2317483-1-coltonlewis@google.com> <20241105195603.2317483-6-coltonlewis@google.com> <007cfed1-111d-45aa-b873-24cca9d4af01@linux.intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@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: <007cfed1-111d-45aa-b873-24cca9d4af01@linux.intel.com> X-Migadu-Flow: FLOW_OUT On Wed, Nov 06, 2024 at 11:07:53AM -0500, Liang, Kan wrote: > > +#ifndef perf_arch_guest_misc_flags > > +static inline unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs) > > +{ > > + unsigned long guest_state = perf_guest_state(); > > + > > + if (guest_state & PERF_GUEST_USER) > > + return PERF_RECORD_MISC_GUEST_USER; > > + > > + if (guest_state & PERF_GUEST_ACTIVE) > > + return PERF_RECORD_MISC_GUEST_KERNEL; > > Is there by any chance to add a PERF_GUEST_KERNEL flag in KVM? Why do we need another flag? As it stands today, the vCPU is either in user mode or kernel mode. > The PERF_GUEST_ACTIVE flag check looks really confusing. Perhaps instead: static inline unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs) { unsigned long guest_state = perf_guest_state(); if (!(guest_state & PERF_GUEST_ACTIVE)) return 0; return (guest_state & PERF_GUEST_USER) ? PERF_RECORD_MISC_GUEST_USER : PERF_RECORD_MISC_GUEST_KERNEL; } -- Thanks, Oliver