From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752203Ab2FROBl (ORCPT ); Mon, 18 Jun 2012 10:01:41 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:5414 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751220Ab2FROBj (ORCPT ); Mon, 18 Jun 2012 10:01:39 -0400 X-Authority-Analysis: v=2.0 cv=NbpkJh/4 c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=XQbtiDEiEegA:10 a=0EZdcKNZKXwA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=ayC55rCoAAAA:8 a=VwQbUJbxAAAA:8 a=QyXUC8HyAAAA:8 a=8YBTT3HPNJrluLShQDwA:9 a=PUjeQqilurYA:10 a=jeBq3FmKZ4MA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-ID: <1340028098.25903.94.camel@gandalf.stny.rr.com> Subject: [PATCH v2][GIT PULL][v3.5] ftrace: Make all inline tags also include notrace From: Steven Rostedt To: LKML Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Fengguang Wu Date: Mon, 18 Jun 2012 10:01:38 -0400 Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.2.2-1+b1 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo, I updated the change log as you recommended, there was no code change. -- Steve Please pull the latest tip/perf/urgent-2 tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git tip/perf/urgent-2 Head SHA1: 93b3cca1ccd30b1ad290951a3fc7c10c73db7313 Steven Rostedt (1): ftrace: Make all inline tags also include notrace ---- include/linux/compiler-gcc.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --------------------------- commit 93b3cca1ccd30b1ad290951a3fc7c10c73db7313 Author: Steven Rostedt Date: Thu Jun 14 10:54:28 2012 -0400 ftrace: Make all inline tags also include notrace Commit 5963e317b1e9d2a ("ftrace/x86: Do not change stacks in DEBUG when calling lockdep") prevented lockdep calls from the int3 breakpoint handler from reseting the stack if a function that was called was in the process of being converted for tracing and had a breakpoint on it. The idea is, before calling the lockdep code, do a load_idt() to the special IDT that kept the breakpoint stack from reseting. This worked well as a quick fix for this kernel release, until a certain config caused a lockup in the function tracer start up tests. Investigating it, I found that the load_idt that was used to prevent the int3 from changing stacks was itself being traced! Even though the config had CONFIG_OPTIMIZE_INLINING disabled, and all 'inline' tags were set to always inline, there were still cases that it did not inline! This was caused by CONFIG_PARAVIRT_GUEST, where it would add a pointer to the native_load_idt() which made that function to be traced. Commit 45959ee7aa645815a ("ftrace: Do not function trace inlined functions") only touched the 'inline' tags when CONFIG_OPMITIZE_INLINING was enabled. PARAVIRT_GUEST shows that this was not enough and we need to also mark always_inline with notrace as well. Reported-by: Fengguang Wu Tested-by: Fengguang Wu Signed-off-by: Steven Rostedt diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index e5834aa..6a6d7ae 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -47,9 +47,9 @@ */ #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) -# define inline inline __attribute__((always_inline)) -# define __inline__ __inline__ __attribute__((always_inline)) -# define __inline __inline __attribute__((always_inline)) +# define inline inline __attribute__((always_inline)) notrace +# define __inline__ __inline__ __attribute__((always_inline)) notrace +# define __inline __inline __attribute__((always_inline)) notrace #else /* A lot of inline functions can cause havoc with function tracing */ # define inline inline notrace