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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 00143EB64DD for ; Sat, 22 Jul 2023 01:23:35 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=qX6KSrLj; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4R77wk1jcxz2yVX for ; Sat, 22 Jul 2023 11:23:34 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=qX6KSrLj; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=kuba@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4R77vh6T8kz3bt5 for ; Sat, 22 Jul 2023 11:22:40 +1000 (AEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0344D61DB8; Sat, 22 Jul 2023 01:22:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A5AEC433C7; Sat, 22 Jul 2023 01:22:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689988957; bh=ymdnVGyJNnGUv2HZI8/M1PK0lCyu640ix4SSxWqfV44=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=qX6KSrLjUNhNPi02nh+6ca0mclsiX8ngx6MgAoXToVEXfxGVJDqDd+M/xrQSvGPdo HnjJABDZ+OFRbofb+JDvnjIEveDSuko/ikgRmWfqsjkq952i36BAMvINTGaChjawkN B6OgwD+8AJO8pd8z/xs4a/6K9P/a/2QBnvpuWam+MrqHhLdmuXK4SwdOcmYgpxe7vM 22q4vDY9qAL+C5nUG3OBKyhHxxOwDvkPnHotsHGxEf6IGBGHRf44LFpW0ECov/5dH/ YZurOS/9kOxHoWBIWBcbE7057VWjExGXUHZp3YSqZogBmtq6DHFSz4dzR5vmf0EeHL 9OCfZ4ADrf3gQ== Date: Fri, 21 Jul 2023 18:22:35 -0700 From: Jakub Kicinski To: Steven Rostedt Subject: Re: [PATCH] tracing: Have all levels of checks prevent recursion Message-ID: <20230721182235.6617a466@kernel.org> In-Reply-To: <20230721122632.56b4df6c@gandalf.local.home> References: <20211015110035.14813389@gandalf.local.home> <20211015161702.GF174703@worktop.programming.kicks-ass.net> <20211015133504.6c0a9fcc@gandalf.local.home> <20211015135806.72d1af23@gandalf.local.home> <20211015180429.GK174703@worktop.programming.kicks-ass.net> <20211015142033.72605b47@gandalf.local.home> <20211015142541.4badd8a9@gandalf.local.home> <1b402c0c-1beb-d93f-ff6d-955350995ca3@intel.com> <20230721120040.6ed2c02a@gandalf.local.home> <035cee53-255b-11a3-d7ac-ca46c05b907b@intel.com> <20230721122632.56b4df6c@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?B?546L6LSH?= , Peter Zijlstra , Paul Walmsley , "James E.J. Bottomley" , Paul Mackerras , Jisheng Zhang , "H. Peter Anvin" , live-patching@vger.kernel.org, linux-riscv@lists.infradead.org, Miroslav Benes , Joe Lawrence , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Ingo Molnar , Petr Mladek , Albert Ou , Jiri Kosina , Nicholas Piggin , Borislav Petkov , Josh Poimboeuf , Thomas Gleixner , linux-parisc@vger.kernel.org, LKML , Alexander Lobakin , Palmer Dabbelt , Masami Hiramatsu , Guo Ren , Colin Ian King , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, 21 Jul 2023 12:26:32 -0400 Steven Rostedt wrote: > > if (!(in_hardirq() || irqs_disabled())) > > > > Yeah, probably. > > > , nothing more elegant / already existing / ...? > > It's not a common check. What would you call that? Looks like Olek started the weekend already so let me answer. He's trying to check if we can use a fast path cache which takes a _bh spin lock.