From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BF85419C56F; Tue, 1 Oct 2024 21:19:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727817555; cv=none; b=c1XcL0jTEMP/S0bcOmjzjSVo07U1TzvMJvnQzR3WNMpcBoApAWVYenYP2DpZ4yVGgWP23r4aScJ96K39kfP8ppOej+kFbRsGR16ZQbYtprfa617rkLi1gin438cqUvPDbXNsJNdjEOL3h+D5tN5Qpo/8n1yT5s2dl8ky9A6xKHg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727817555; c=relaxed/simple; bh=244LgueFRtPdrYTYFFh1neNOJHKmMrFxLaO4qT37TdI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=U4v8dkd5QkqW7lnLGWbGmavfdP4XyLkhtyHSn4tgMxVJBMVYtKpUcKGFQh2cbJRQC2ntVcE96EI5myyh8wu6sMURd977yfaA6gVJef+gjScbLQr8ET9HkIQ7l0jrtCPgY8Ir+sVYeXbulH7ne/lw4cjF7HXGxGY4MSczIVJAm5g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VuFbAORd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VuFbAORd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBC2AC4CEC6; Tue, 1 Oct 2024 21:19:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727817555; bh=244LgueFRtPdrYTYFFh1neNOJHKmMrFxLaO4qT37TdI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VuFbAORdc5igqvJcV+l36uysAL/HAooTfAqXKCLQ7Ezo44aOp2sYKrY1MzcCa8eK9 Mc3b1o3VqCMWCKSmHaZqQUTHGzVOFN5be1fXFXzZJC0D7PgxUBda5jn7fKkPsibmf8 lOwW3NS/DHOuN02skoAv59Xayrbp6qn1/swV14MITq5REkSADBsP7+pM9XUGyCZ35j uILqPTsuTspsxu2V3MK7hGPClF4ZbxiZqMVbaVuAnNdAYIExKJIAUmFqRXjMtIu9+B +1WK9rnT7LwmUrU+y/buwX3G/d5VkkPRg75xyeAmek9Vf6OIV905oErk1JEYUc71OO Db5VaH8tE5AXg== Date: Tue, 1 Oct 2024 14:19:13 -0700 From: Namhyung Kim To: "Liang, Kan" Cc: Arnaldo Carvalho de Melo , Ian Rogers , Jiri Olsa , Adrian Hunter , Peter Zijlstra , Ingo Molnar , LKML , linux-perf-users@vger.kernel.org, Ravi Bangoria , Mark Rutland , James Clark , Kajol Jain , Thomas Richter , Atish Patra , Palmer Dabbelt , Mingwei Zhang Subject: Re: [PATCHSET 0/8] perf tools: Do not set attr.exclude_guest by default (v4) Message-ID: References: <20241001002027.1272889-1-namhyung@kernel.org> <4ce19789-eea1-4e5e-9269-13bd78d846c2@linux.intel.com> 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=utf-8 Content-Disposition: inline In-Reply-To: <4ce19789-eea1-4e5e-9269-13bd78d846c2@linux.intel.com> On Tue, Oct 01, 2024 at 01:46:36PM -0400, Liang, Kan wrote: > > > On 2024-09-30 8:20 p.m., Namhyung Kim wrote: > > Hello, > > > > I found perf tools set exclude_guest bit inconsistently. It used to > > set the bit but now the default event for perf record doesn't. So I'm > > wondering why we want the bit in the first place. > > > > Actually it's not good for PMUs don't support any exclusion like AMD > > IBS because it disables new features after the exclude_guest due to > > the missing feature detection logic. > > > > v4 changes) > > > > * handle EOPNOTSUPP error in compatible way (Kan) > > * drop --exclude-guest option in perf stat > > * not to separate exclude_hv fallback > > * rename to exclude_GH_default (Kan) > > * drop the RFC from the subject > > > > v3) https://lore.kernel.org/lkml/20240905202426.2690105-1-namhyung@kernel.org/ > > > > * move exclude_guest fallback to the front > > * fix precise_max handling on AMD > > * simplify the default event for perf record > > > > v2) https://lore.kernel.org/lkml/20240904064131.2377873-1-namhyung@kernel.org/ > > > > * update the missing feature detection logic > > * separate exclude_hv fallback > > * add new fallback for exclude_guest > > > > v1) https://lore.kernel.org/lkml/20240902014621.2002343-1-namhyung@kernel.org/ > > > > AFAIK it doesn't matter for the most cases but perf kvm. If users > > need to set the bit, they can still use :H modifier. For vPMU pass- > > through or Apple M1, it'd add the exclude_guest during the fallback > > logic. > > > > Also the kernel feature detection logic should be separated from the > > exclude bit tests since it depends on the PMU implementation rather > > than the core kernel features. So I changed it to use a software > > event for the detection and factor out some hw-specific checks. > > > > The code is available at 'perf/exclude-v4' branch in > > git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git > > > > Thanks, > > Namhyung > > > > > > Namhyung Kim (8): > > perf tools: Add fallback for exclude_guest > > perf tools: Don't set attr.exclude_guest by default > > perf tools: Simplify evsel__add_modifier() > > perf tools: Do not set exclude_guest for precise_ip > > perf tools: Detect missing kernel features properly > > perf tools: Move x86__is_amd_cpu() to util/env.c > > perf tools: Check fallback error and order > > perf record: Just use "cycles:P" as the default event > > > > The patch set looks good to me. > > Acked-by: Kan Liang Thanks for your review! Namhyung