From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) (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 6B2302F50A8; Wed, 2 Jul 2025 16:47:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751474870; cv=none; b=N2diBuiJeuWygCRJlxsBl3OUMMh2ibI7kvdrSkHnLouvTn4IBOW0+BvH+L7ZrmNbIw1qfnhz7A2xiRMXIWw5EMBuAlbXHLmHllQwUlIaWhWXZ85ych5p6IgkWWh+6fv36n2ewzWgL9faKHZ+jpyjr/C1uBgBXTmK925YxNN0dZc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751474870; c=relaxed/simple; bh=g1+k2nPM6RxeEUCvtw0vrTy0LPvjf9hZ6rmLV2y9xgU=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=QeP0IB3XWtZi6CzLh7kPAbjNQXgVRG9iYcMCEEYnszNR41TKLfyDLHJx+WWYE439HMvR3udW8QQj5fAtb4Edhov8bEiDWohqi73FSgEl3e55AjwGbnW7uTbykGTJgNHLVMmrqKFn9vWmthXB8zc77iFuwML1lOboGs9NFMLTtn0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id B8157140367; Wed, 2 Jul 2025 16:47:43 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf12.hostedemail.com (Postfix) with ESMTPA id 1BC9B1A; Wed, 2 Jul 2025 16:47:39 +0000 (UTC) Date: Wed, 2 Jul 2025 12:47:37 -0400 From: Steven Rostedt To: Jens Remus Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, Indu Bhagat , Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , "Jose E. Marchesi" , Beau Belgrave , Linus Torvalds , Andrew Morton , Jens Axboe , Florian Weimer , Heiko Carstens , Vasily Gorbik Subject: Re: [PATCH v7 00/12] unwind_deferred: Implement sframe handling Message-ID: <20250702124737.565934b5@batman.local.home> In-Reply-To: <7eea50a5-e1b0-4319-9a25-cb8b327a836d@linux.ibm.com> References: <20250701184939.026626626@goodmis.org> <7eea50a5-e1b0-4319-9a25-cb8b327a836d@linux.ibm.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 1BC9B1A X-Stat-Signature: 6ab6bcboemhxxcrt1jugnewqbfujyn9q X-Rspamd-Server: rspamout06 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+RCYfk1ij87wG5Mg8mX6pSoPsPrUnbTOI= X-HE-Tag: 1751474859-717133 X-HE-Meta: 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 On Wed, 2 Jul 2025 14:57:22 +0200 Jens Remus wrote: > Hello Steve! > > On 01.07.2025 20:49, Steven Rostedt wrote: > > This code is based on top of: > > > > https://lore.kernel.org/linux-trace-kernel/20250701005321.942306427@goodmis.org/ > > git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git unwind/core > > > > This is the implementation of parsing the SFrame section in an ELF file. > > ... > > > The code for this patch series can be found here: > > > > git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git unwind/sframe > > Wouldn't it make sense to include your related perf (tools) series [1] > in that branch to ease testing? Provided you also include the minor > fix [2] to make perf tools work. :-) I was planning on making a branch with perf and sframe merged (haven't pushed it out yet). Since sframe doesn't technically rely on it (I use tracing too test it too) I'm keeping them separate. > > Additionally it would make sense to include the patches from Josh that > add SFrame information to the vDSO on x86 [3]. > > [1]: [PATCH v12 00/11] perf: Support the deferred unwinding infrastructure, > https://lore.kernel.org/linux-trace-kernel/20250701180410.755491417@goodmis.org/ > > [2]: https://lore.kernel.org/linux-trace-kernel/51903e66-56bc-42a4-b80c-9c3223e2a48a@linux.ibm.com/ > > [3]: [PATCH v6 0/6] x86/vdso: VDSO updates and fixes for sframes, > https://lore.kernel.org/all/20250425023750.669174660@goodmis.org/ I have them in separate branches too and will be posting them separately. Again, the "merged" branch will contain them all. > > > Changes since v6: https://lore.kernel.org/linux-trace-kernel/20250617225009.233007152@goodmis.org/ > > > - Moved the addition of the prctl(), that allows libraries to add the elf > > sections to the kernel, to the last patch and labeled it as "DO NOT APPLY". > > This should instead be a proper system call and work to make it robust and > > flexible still needs to be done. The prctl() patch is added for debugging > > purposes only. > > Does PR_SET_VMA [4] create a precedent case for the SFrame prctls? > > [4]: https://man7.org/linux/man-pages/man2/pr_set_vma.2const.html > At the last sframe meeting we came to the decision to make it a proper system call. Just seems cleaner that way. If others feel prctl() is the way to go, we can definitely do that too. -- Steve