Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1264BC74A5B for ; Sat, 18 Mar 2023 15:17:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229794AbjCRPRF (ORCPT ); Sat, 18 Mar 2023 11:17:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59376 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229553AbjCRPRD (ORCPT ); Sat, 18 Mar 2023 11:17:03 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23A7D303E9; Sat, 18 Mar 2023 08:17:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=RQqhoBxESfjz0MrhZuxEnWRoFia7U0MNzcHrY8Fhlv0=; b=d6ccJIc0boouKz1RgK4pvpGHi8 4ZkGSh7ToGcaKfREyF2r2iGLEPicussMx8K0l2Li2ra249nXJO7hUZf38itouaruulqS1aOFTKTqN jJMx2gb8RC+xEru4EMEUbXlbziGm+fW8Fml8xSUcNodEmfqS15SK8uCirMJIR9JVRKxZaBwPAD74R K9n/THstFMW9NglqvNtSQmYgeP646r9HesxPdRri63hl3iM8CtBAdvbnwf953h05nlX4Ap9z9DTvP 3+UTf5Zp5V2ZQKQBjwv/jwj26batJCHJXAy8GoUDqoSLOsLOteidAWyQR8ImH4PUgpewvrOdjbLIg 85rR280A==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pdYIX-00Gudm-D6; Sat, 18 Mar 2023 15:16:45 +0000 Date: Sat, 18 Mar 2023 15:16:45 +0000 From: Matthew Wilcox To: Jiri Olsa Cc: Alexei Starovoitov , Andrii Nakryiko , Hao Luo , Andrew Morton , Alexander Viro , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , bpf@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-perf-users@vger.kernel.org, Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Daniel Borkmann , Namhyung Kim , Dave Chinner Subject: Re: [PATCHv3 bpf-next 0/9] mm/bpf/perf: Store build id in file object Message-ID: References: <20230316170149.4106586-1-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 18, 2023 at 09:33:49AM +0100, Jiri Olsa wrote: > On Thu, Mar 16, 2023 at 05:34:41PM +0000, Matthew Wilcox wrote: > > On Thu, Mar 16, 2023 at 06:01:40PM +0100, Jiri Olsa wrote: > > > hi, > > > this patchset adds build id object pointer to struct file object. > > > > > > We have several use cases for build id to be used in BPF programs > > > [2][3]. > > > > Yes, you have use cases, but you never answered the question I asked: > > > > Is this going to be enabled by every distro kernel, or is it for special > > use-cases where only people doing a very specialised thing who are > > willing to build their own kernels will use it? > > I hope so, but I guess only time tell.. given the response by Ian and Andrii > there are 3 big users already So the whole "There's a config option to turn it off" shtick is just a fig-leaf. I won't ever see it turned off. You're imposing the cost of this on EVERYONE who runs a distro kernel. And almost nobody will see any benefits from it. Thanks for admitting that.