From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 83F5C42EEC4; Fri, 11 Sep 2026 10:41:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789123318; cv=none; b=ENoSwDTm2el1VqvxfbfPctRUEcC2QMj8EPkohd8GfiSeC0uEM8evenaRImOJ/LjvWPnjH+QG9PVF+nCQiJcNZe1oj71CisjwqixwLooQADMcs63DhwJmH+RMPDheXsE70s71ZSD9D16ZUm6sjDxeevxSWLtThBLzcwMxjUmq8Z0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789123318; c=relaxed/simple; bh=5YCaSg6B8lnKNS5mnwM54lBHOHshfmcrbaZ2cubXQ4k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JX2H7kzq6nu6BHrEn9IC5RMfJyAuoHN6sqgRcNhttkz5QPXPuzSFdJ/fQJxBOVXM48yJ4hJqpbtFWarJ9NVKm0YFsMahFZZriumXOyUPhjDfI4DpDXZBOeIPsfQeDgtTc3/dRMnNN1eoy68NxTbE1Hr4sGUvazymPAJI56XrdvY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hcs4lsBd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hcs4lsBd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E852A1F00893; Fri, 11 Sep 2026 10:41:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789123317; bh=MMJozD+RewnE2WYnIY4zmGHYgUsIL3AEVPRTDj0LFp8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=hcs4lsBdMwnW3lvB6exZIai5ol6Yll7bG/D1+ACDRwDpO3fOZPtNZtrr/wRrMfVnF 2j60pbtJ6hWpfKQa7KB2OZKJ6MVp/0vCxO6uHD6KrHWQqBZ6kEPkhf7pZQJr/102YE T1jWWci85XBcjR4t7bz+BKek9UUwRB2J3+EJ11gmbc4zCByQt1yfpJBpmjxqNfMqkG 3ToKl+ijDkkohsVu6wnXupOLnIvcJUBY0ztyBT2+7I01TALqv+YgH4HIxdTJWXPF21 OCt+c8Um107UgPvZi5Npr/ihPA+ggNXAevh4vJJClnZvexnYba42/50f1AwJmO7j+o 2kw3fJzuWq5fA== Date: Fri, 11 Sep 2026 11:41:43 +0100 From: "Lorenzo Stoakes (ARM)" To: Petr Pavlu Cc: Linus Torvalds , Nathan Chancellor , Nicolas Schier , Nick Desaulniers , Bill Wendling , Justin Stitt , Masahiro Yamada , Alexey Gladkov , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Arnd Bergmann , Catalin Marinas , Will Deacon , Mark Rutland , Ard Biesheuvel , Ilias Apalodimas , Josh Poimboeuf , Peter Zijlstra , Miguel Ojeda , Boqun Feng , Gary Guo , =?utf-8?B?QmrDtnJu?= Roy Baron , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Daniel Almeida , Tamir Duberstein , Alexandre Courbot , Onur =?utf-8?B?w5Z6a2Fu?= , Jonathan Corbet , Randy Dunlap , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-efi@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-doc@vger.kernel.org, Jens Axboe Subject: Re: [PATCH 13/23] modpost: hash module source per-file, not per-byte Message-ID: References: <20260908-build-speedup-v1-0-5dc1ac01672d@kernel.org> <20260908-build-speedup-v1-13-5dc1ac01672d@kernel.org> <434a7a10-d83e-4402-be91-816bbbc15bb7@suse.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=us-ascii Content-Disposition: inline In-Reply-To: <434a7a10-d83e-4402-be91-816bbbc15bb7@suse.com> On Thu, Sep 10, 2026 at 02:52:50PM +0200, Petr Pavlu wrote: > On 9/8/26 10:55 PM, Lorenzo Stoakes (ARM) wrote: > > modpost spends a long time md4 hashing module source at a per-byte > > granularity. > > > > Fix this by doing this hashing per-file instead by accumulating a per-file > > buffer in parse_file(). > > > > All 11,189 .mod.c files and Module.symvers were confirmed to be identical > > with this change applied. > > > > This is especially impactful for allmodconfig incremental builds (where > > CONFIG_MODULE_SRCVERSION_ALL is set). > > > > Whole build, 128-thread Threadripper 9980X, best of N runs: > > > > before after delta > > ------------------------------- > > x86 allmodconfig, touch mm/vma.c, gcc 40.6s 38.2s -2.4s (-6%) > > x86 allmodconfig, touch mm/vma.c, clang 36.2s 35.0s -1.2s (-3%) > > > > Assisted-by: LLM > > Signed-off-by: Lorenzo Stoakes (ARM) > > --- > > scripts/mod/sumversion.c | 56 +++++++++++++++++++++++++++++++++++++----------- > > 1 file changed, 44 insertions(+), 12 deletions(-) > > Support for the module srcversion is being removed in "module: remove > MODULE_VERSION() and srcversion" [1] and scripts/mod/sumversion.c should > be gone completely. Hmm, that series doesn't remove the script though, is that planned as a follow up? I guess I can drop this patch from the series then :) Also patch 17 I think? > > [1] https://lore.kernel.org/linux-modules/20260731-module_ver_remove-v2-0-c9163858f382@linuxfoundation.org/ > > -- > Thanks, > Petr -- Cheers, Lorenzo