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 75B2229413; Fri, 26 Apr 2024 20:47:18 +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=1714164438; cv=none; b=u+cSotJ0vMH3FfImOIBWUn1ZDRiiwndWPbeQRnUhfn3UEukiT+6C4CvcCR4UH9+3XxVa7c6FkuegajQM95At0keSJdJ/K63b+DYyxLNOWd5a5djwt82W5ixPD3Wt90oKddmO4FuwelC7iXK8hxigjqPLGH6izFTVC+N6MIUFb2w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714164438; c=relaxed/simple; bh=Ke6PnaHuYXUrGk7n/xW6HyC1qaYwrCBZDcX7ANMfGWY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gHS6/NKMc6tAzIWJUD+6zpfZwKElKDzTfFve9Kls/LcdzcENadjbK6s67pwpVBqYYMSw9wxnCy+6oJOIQnkTUZMblckWxAPq0qWkw61ciE4DmuQEZo36VDB8HmKFxP0+2pPiilXM2R3Xf8UJiEwHmEW6EtCXtpOiUlH3j6PE0CA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qBz7hXo4; 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="qBz7hXo4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD4DDC113CD; Fri, 26 Apr 2024 20:47:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714164438; bh=Ke6PnaHuYXUrGk7n/xW6HyC1qaYwrCBZDcX7ANMfGWY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qBz7hXo4rPfBVSzAt/h9RqUYJ6HtKJ6MAEogFiX/SRumIAjps5Babc4J6bhGLIlN7 CkpEzt0H1HC61eCNUksLD573m8vd3yXQ0uT2VlDwUICkw01oWntcpgRUsajIRjDs+w wZ0DeuaFSFOsq+bbfYvC1iJ/ZIRoHKSRxcydKUWSPY+1yFnDC+B9kBgpoIHLh4k9C6 Kh+V7KLtpoa+F8leIcypKfqhMjAnMrIQqSE36TuiTb59kFiMWTdF4RXrIv8CbMU8el EubzDxBl0WI1u/lumPHC7RDZemKC0Qr7WdB5G8Lz6OSmfXbX9pua8Wz9dBiMh55Cp3 Jx18e5eZuQucw== Date: Fri, 26 Apr 2024 17:47:15 -0300 From: Arnaldo Carvalho de Melo To: Andrii Nakryiko Cc: dwarves@vger.kernel.org, Jiri Olsa , Clark Williams , Kate Carcia , bpf@vger.kernel.org, Arnaldo Carvalho de Melo , Alan Maguire , Daniel Xu , Eduard Zingerman Subject: Re: [PATCH 2/2] pahole: Allow asking for extra features using the '+' prefix in --btf_features Message-ID: References: <20240419205747.1102933-1-acme@kernel.org> <20240419205747.1102933-3-acme@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Apr 26, 2024 at 01:26:40PM -0700, Andrii Nakryiko wrote: > On Fri, Apr 19, 2024 at 1:58 PM Arnaldo Carvalho de Melo > wrote: > > > > From: Arnaldo Carvalho de Melo > > > > Instead of the somewhat confusing: > > > > --btf_features=all,reproducible_build > > > > That means "'all' the standard BTF features plus the 'reproducible_build' > > extra BTF feature", use + directly, making it more compact: > > > > --btf_features=+reproducible_build > > > > for older paholes that don't yet know about + syntax, but support > --btf_features, will this effectively disable all features or how will > it work? > > I'm thinking from the perspective of using +reproducible_build > unconditionally in kernel's build scripts, will it regress something > for current pahole versions? Well, I think it will end up being discarded just like "all" or "default", no? I.e. those were keywords not grokked by older pahole versions, so ignored as we're not using --btf_features_strict, right? Alan? But then we're not yet using --btf_features in scripts/Makefile.btf, right? But as Daniel pointed out and Alan (I think) agreed, for things like scripts we probably end up using the most verbose thing as: --btf_features=default,reproducible_build to mean a set (the default set of BTF options) + an optional/extra feature (reproducibe_build), that for people not used to the + syntax may be more descriptive (I really think that both are confusing for beginners knowing nothing about BTF and its evolution, etc). Alan, also we released 1.26 with "all" meaning what we now call "default", so we need to keep both meaning the same thing, right? - Arnaldo > > In the future we may want the '-' counterpart as a way to _remove_ some > > of the standard set of BTF features. > > > > Cc: Alan Maguire > > Cc: Andrii Nakryiko > > Cc: Daniel Xu > > Cc: Eduard Zingerman > > Cc: Jiri Olsa > > Signed-off-by: Arnaldo Carvalho de Melo > > --- > > man-pages/pahole.1 | 6 ++++++ > > pahole.c | 6 ++++++ > > tests/reproducible_build.sh | 2 +- > > 3 files changed, 13 insertions(+), 1 deletion(-) > > > > [...]