Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751537AbaKXCMO (ORCPT ); Sun, 23 Nov 2014 21:12:14 -0500 Received: from mail7.hitachi.co.jp ([133.145.228.42]:39253 "EHLO mail7.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750804AbaKXCMN (ORCPT ); Sun, 23 Nov 2014 21:12:13 -0500 Message-ID: <547293F6.8090008@hitachi.com> Date: Mon, 24 Nov 2014 11:12:06 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Steven Rostedt Cc: Josh Poimboeuf , Ananth N Mavinakayanahalli , Jiri Kosina , Seth Jennings , Linux Kernel Mailing List , Petr Mladek , Vojtech Pavlik , Namhyung Kim , Miroslav Benes , Ingo Molnar Subject: Re: [PATCH ftrace/core v6 2/5] ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict References: <20141121102502.11844.82696.stgit@localhost.localdomain> <20141121102516.11844.27829.stgit@localhost.localdomain> <20141121130529.316989d8@gandalf.local.home> <20141121144316.22459f7e@gandalf.local.home> In-Reply-To: <20141121144316.22459f7e@gandalf.local.home> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2014/11/22 4:43), Steven Rostedt wrote: > On Fri, 21 Nov 2014 13:05:29 -0500 > Steven Rostedt wrote: > >> On Fri, 21 Nov 2014 05:25:16 -0500 >> Masami Hiramatsu wrote: > >>> + * IPMODIFY - The ops can modify the IP register. This can only be set with >>> + * SAVE_REGS. If another ops is already registered for any of the >>> + * functions that this ops will be registered for, then this ops >>> + * will fail to register or set_filter_ip. >> >> It's blocked by any ops sharing the same function, or just another ops >> with this flag set? The comment doesn't specify. The code looks like >> the latter. > > I applied it and gave it the following updates to comments: Thanks! This looks good to me :) > > -- Steve > > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index 93cf0478f64e..ed501953f0b2 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -107,9 +107,9 @@ ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); > * in such cases the arch must not modify it. Only the arch ftrace > * core code should set this flag. > * IPMODIFY - The ops can modify the IP register. This can only be set with > - * SAVE_REGS. If another ops is already registered for any of the > - * functions that this ops will be registered for, then this ops > - * will fail to register or set_filter_ip. > + * SAVE_REGS. If another ops with this flag set is already registered > + * for any of the functions that this ops will be registered for, then > + * this ops will fail to register or set_filter_ip. > */ > enum { > FTRACE_OPS_FL_ENABLED = 1 << 0, > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index 531e72a716c3..929a733d302e 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -1810,8 +1810,8 @@ static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, > return 0; > > /* > - * Since the IPMODIFY is very address sensitive action, we do not allow > - * ftrace_ops to set all functions to new hash. > + * Since the IPMODIFY is a very address sensitive action, we do not > + * allow ftrace_ops to set all functions to new hash. > */ > if (!new_hash || !old_hash) > return -EINVAL; > -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research 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/