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 X-Spam-Level: X-Spam-Status: No, score=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF13BC2D0A3 for ; Fri, 6 Nov 2020 13:18:08 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E194020702 for ; Fri, 6 Nov 2020 13:18:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=suse.com header.i=@suse.com header.b="M+tR/rKx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E194020702 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4CSLY85qd1zDrFK for ; Sat, 7 Nov 2020 00:18:04 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=suse.com (client-ip=195.135.220.15; helo=mx2.suse.de; envelope-from=pmladek@suse.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=suse.com Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=suse.com header.i=@suse.com header.a=rsa-sha256 header.s=susede1 header.b=M+tR/rKx; dkim-atps=neutral Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4CSLRl1QX6zDrFK for ; Sat, 7 Nov 2020 00:13:21 +1100 (AEDT) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604668398; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/qFlNeW+fj9kPag6iPvAKbxfuQxHVIdXyO+NAnfQv1k=; b=M+tR/rKxslTPuT6FfxTzbpuuxYbiZZG3CnqFYk93k8am/VLmSymRvyUiwOy4Hr5waPoLce uQiZvPathsmCgazo7IfORam7PuE22q5xJHq/iNivwhCmxch4+MaufWlLk/oXEAcDNCMlcc x3wJTN1WOECehMoqwdLrqgU3bZ/wBxo= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 6BB69AB8F; Fri, 6 Nov 2020 13:13:18 +0000 (UTC) Date: Fri, 6 Nov 2020 14:13:17 +0100 From: Petr Mladek To: Steven Rostedt Subject: Re: [PATCH 11/11 v3] ftrace: Add recording of functions that caused recursion Message-ID: <20201106131317.GW20201@alley> References: <20201106023235.367190737@goodmis.org> <20201106023548.102375687@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201106023548.102375687@goodmis.org> 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: Anton Vorontsov , linux-doc@vger.kernel.org, Peter Zijlstra , Sebastian Andrzej Siewior , Kamalesh Babulal , "James E.J. Bottomley" , Guo Ren , "H. Peter Anvin" , live-patching@vger.kernel.org, Miroslav Benes , Ingo Molnar , linux-s390@vger.kernel.org, Joe Lawrence , Jonathan Corbet , Mauro Carvalho Chehab , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Christian Borntraeger , Kees Cook , Vasily Gorbik , Heiko Carstens , Jiri Kosina , Borislav Petkov , Josh Poimboeuf , Thomas Gleixner , Tony Luck , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, Masami Hiramatsu , Colin Cross , Paul Mackerras , Andrew Morton , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu 2020-11-05 21:32:46, Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" > > This adds CONFIG_FTRACE_RECORD_RECURSION that will record to a file > "recursed_functions" all the functions that caused recursion while a > callback to the function tracer was running. > > Changes since v2: > > - Use trace_recursion flags in current for protecting recursion of recursion recording > - Make the recursion logic a little cleaner > - Export GPL the recursion recording JFYI, the code reading and writing the cache looks good to me. It is still possible that some entries might stay unused (filled with zeroes) but it should be hard to hit in practice. It is good enough from my POV. I do not give Reviewed-by tag just because I somehow do not have power to review the entire patch carefully enough at the moment. Best Regards, Petr