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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham 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 537D9C43441 for ; Tue, 27 Nov 2018 19:31:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 18E6F20645 for ; Tue, 27 Nov 2018 19:31:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 18E6F20645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726345AbeK1Ga3 (ORCPT ); Wed, 28 Nov 2018 01:30:29 -0500 Received: from foss.arm.com ([217.140.101.70]:46556 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725764AbeK1Ga2 (ORCPT ); Wed, 28 Nov 2018 01:30:28 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AE1972EDF; Tue, 27 Nov 2018 11:31:32 -0800 (PST) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7DBA03F575; Tue, 27 Nov 2018 11:31:32 -0800 (PST) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 5F55C1AE0A0D; Tue, 27 Nov 2018 19:31:50 +0000 (GMT) Date: Tue, 27 Nov 2018 19:31:50 +0000 From: Will Deacon To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , Thomas Gleixner , Peter Zijlstra , Masami Hiramatsu , Josh Poimboeuf , Frederic Weisbecker , Joel Fernandes , Andy Lutomirski , Mark Rutland , Catalin Marinas , linux-arm-kernel@lists.infradead.org Subject: Re: [RFC][PATCH 03/14] arm64: function_graph: Remove use of FTRACE_NOTRACE_DEPTH Message-ID: <20181127193149.GJ5641@arm.com> References: <20181122012708.491151844@goodmis.org> <20181122012803.040221352@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181122012803.040221352@goodmis.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Steve, On Wed, Nov 21, 2018 at 08:27:11PM -0500, Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" > > The curr_ret_stack is no longer set to -1 when not tracing a function. It is > now done differently, and the FTRACE_NOTRACE_DEPTH value is no longer used. > Remove the reference to it. Do you have a pointer to the commit that changed that behaviour? I just want to make sure we're not missing something in our unwind_frame() code. > Cc: Catalin Marinas > Cc: Will Deacon > Cc: linux-arm-kernel@lists.infradead.org > Signed-off-by: Steven Rostedt (VMware) > --- > arch/arm64/kernel/stacktrace.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c > index 4989f7ea1e59..7723dadf25be 100644 > --- a/arch/arm64/kernel/stacktrace.c > +++ b/arch/arm64/kernel/stacktrace.c > @@ -61,9 +61,6 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) > (frame->pc == (unsigned long)return_to_handler)) { > if (WARN_ON_ONCE(frame->graph == -1)) > return -EINVAL; Hmm, so is this code redundant too ^^ ? > - if (frame->graph < -1) > - frame->graph += FTRACE_NOTRACE_DEPTH; > - Do we still need to initialise frame->graph in __save_stack_trace()? Will