From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967989AbdEWTxr (ORCPT ); Tue, 23 May 2017 15:53:47 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:54486 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967057AbdEWTxo (ORCPT ); Tue, 23 May 2017 15:53:44 -0400 Date: Tue, 23 May 2017 20:53:18 +0100 From: Russell King - ARM Linux To: Abel Vesa Cc: robin.murphy@arm.com, jjhiblot@traphandler.com, nicstange@gmail.com, Steven Rostedt , Ingo Molnar , pmladek@suse.com, mhiramat@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm: ftrace: Adds support for CONFIG_DYNAMIC_FTRACE_WITH_REGS Message-ID: <20170523195318.GC22219@n2100.armlinux.org.uk> References: <1494623207-17195-1-git-send-email-abelvesa@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1494623207-17195-1-git-send-email-abelvesa@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 12, 2017 at 10:06:47PM +0100, Abel Vesa wrote: > The DYNAMIC_FTRACE_WITH_REGS configuration makes it possible for a ftrace > operation to specify if registers need to saved/restored by the ftrace handler. > This is needed by kgraft and possibly other ftrace-based tools, and the ARM > architecture is currently lacking this feature. It would also be the first step > to support the "Kprobes-on-ftrace" optimization on ARM. > > This patch introduces a new ftrace handler that stores the registers on the > stack before calling the next stage. The registers are restored from the stack > before going back to the instrumented function. > > A side-effect of this patch is to activate the support for ftrace_modify_call() > as it defines ARCH_SUPPORTS_FTRACE_OPS for the ARM architecture. With the exception of the long lines in the commit message (please wrap before column 72 so that 'git log' is readable on 80 column displays) I think this is fine. Please amend the commit message and sent to the patch system. Thanks. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.