From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E0E11C433F5 for ; Fri, 25 Mar 2022 20:46:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 27E636B0071; Fri, 25 Mar 2022 16:46:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 22D536B0073; Fri, 25 Mar 2022 16:46:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0F5B76B0074; Fri, 25 Mar 2022 16:46:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id 0004C6B0071 for ; Fri, 25 Mar 2022 16:46:38 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id A735746F for ; Fri, 25 Mar 2022 20:46:33 +0000 (UTC) X-FDA: 79284091866.04.F29F090 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf22.hostedemail.com (Postfix) with ESMTP id 06E05C0032 for ; Fri, 25 Mar 2022 20:46:32 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DA70A61D49; Fri, 25 Mar 2022 20:46:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0282C004DD; Fri, 25 Mar 2022 20:46:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648241191; bh=LQFKt10LSmaGE3MEo4zcNZRff2M+N1aNeUHBztWpOKU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RQR4hHILpnUkhfu7+xcMiRIk0v6yjyvIksOfM5LPSTaUIq8cNLk0oV//EXe/qB4TA wb6Xx6B86gAcULNcU2IBwbfuhjAyTB7Mqxmu/jC1WIUVC69FLplcSGiCgEkUrF5sHC Vz/3RusidENiid01E61425EVB8K4qKlLLgEfFkyQ= Date: Fri, 25 Mar 2022 13:46:29 -0700 From: Andrew Morton To: andrey.konovalov@linux.dev Cc: Marco Elver , Alexander Potapenko , Catalin Marinas , Will Deacon , Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Mark Rutland , Vincenzo Frascino , Sami Tolvanen , Peter Collingbourne , Evgenii Stepanov , Florian Mayer , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Subject: Re: [PATCH v2 1/4] stacktrace: add interface based on shadow call stack Message-Id: <20220325134629.99699c921bb8c8db413e8e35@linux-foundation.org> In-Reply-To: <21e3e20ea58e242e3c82c19abbfe65b579e0e4b8.1648049113.git.andreyknvl@google.com> References: <21e3e20ea58e242e3c82c19abbfe65b579e0e4b8.1648049113.git.andreyknvl@google.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: yn9ayax4y6ma85obw8owf4m4wa5edk4c Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=RQR4hHIL; dmarc=none; spf=pass (imf22.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 06E05C0032 X-HE-Tag: 1648241192-293938 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 23 Mar 2022 16:32:52 +0100 andrey.konovalov@linux.dev wrote: > From: Andrey Konovalov > > Add a new interface stack_trace_save_shadow() for collecting stack traces > by copying frames from the Shadow Call Stack. > > Collecting stack traces this way is significantly faster: boot time > of a defconfig build with KASAN enabled gets descreased by ~30%. > > The few patches following this one add an implementation of > stack_trace_save_shadow() for arm64. > > The implementation of the added interface is not meant to use > stack_trace_consume_fn to avoid making a function call for each > collected frame to further improve performance. > > ... > > @@ -108,4 +111,16 @@ static inline int stack_trace_save_tsk_reliable(struct task_struct *tsk, > } > #endif > > +#if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_SHADOW_STACKTRACE) > +int stack_trace_save_shadow(unsigned long *store, unsigned int size, > + unsigned int skipnr); > +#else > +static inline int stack_trace_save_shadow(unsigned long *store, > + unsigned int size, > + unsigned int skipnr) > +{ > + return -ENOSYS; > +} > +#endif checkpatch sayeth "WARNING: ENOSYS means 'invalid syscall nr' and nothing else". checkpatch also picked up a typo in a changelog. Useful thing to run, is checkpatch.