Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946152Ab2EROT5 (ORCPT ); Fri, 18 May 2012 10:19:57 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:55575 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946137Ab2EROTy (ORCPT ); Fri, 18 May 2012 10:19:54 -0400 X-AuditID: b753bd60-98392ba000007b1b-8d-4fb65a880c6a X-AuditID: b753bd60-98392ba000007b1b-8d-4fb65a880c6a Message-ID: <4FB65A85.8070700@hitachi.com> Date: Fri, 18 May 2012 23:19:49 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , Frederic Weisbecker , yrl.pp-manager.tt@hitachi.com Subject: Re: [PATCH 12/15] ftrace: Return record ip addr for ftrace_location() References: <20120518130858.392919640@goodmis.org> <20120518131051.251652937@goodmis.org> In-Reply-To: <20120518131051.251652937@goodmis.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1292 Lines: 36 (2012/05/18 22:09), Steven Rostedt wrote: > From: Steven Rostedt > > ftrace_location() is passed an addr, and returns 1 if the addr is > on a ftrace nop (or caller to ftrace_caller), and 0 otherwise. > > To let kprobes know if it should move a breakpoint or not, itH > must return the actual addr that is the start of the ftrace nop. > This way a kprobe placed on the location of a ftrace nop, can > instead be placed on the instruction after the nop. Even if the > probe addr is on the second or later byte of the nop, it can > simply be moved forward. > > Cc: Masami Hiramatsu > Signed-off-by: Steven Rostedt This looks good to me:) Acked-by: Masami Hiramatsu Thanks! P.S. Steven, ftrace-based optimization is under development with both i386/x86-64 support :) -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/