lkml.org 
[lkml]   [2012]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:perf/core] ftrace: Make recordmcount.c handle __fentry__
Commit-ID:  48bb5dc6cd9d30fe0d594947563da1f8bd9abada
Gitweb: http://git.kernel.org/tip/48bb5dc6cd9d30fe0d594947563da1f8bd9abada
Author: Steven Rostedt <srostedt@redhat.com>
AuthorDate: Wed, 9 Feb 2011 13:13:23 -0500
Committer: Steven Rostedt <rostedt@goodmis.org>
CommitDate: Thu, 23 Aug 2012 11:24:43 -0400

ftrace: Make recordmcount.c handle __fentry__

With gcc 4.6.0 the -mfentry feature places the function profiling
call at the start of the function. When this is used, the call is
to __fentry__ and not mcount.

Change recordmcount.c to record both callers to __fentry__ and
mcount.

Link: http://lkml.kernel.org/r/20120807194058.990674363@goodmis.org

Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: John Reiser <jreiser@bitwagon.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
scripts/recordmcount.h | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h
index 54e35c1..9d1421e 100644
--- a/scripts/recordmcount.h
+++ b/scripts/recordmcount.h
@@ -261,11 +261,13 @@ static unsigned get_mcountsym(Elf_Sym const *const sym0,
&sym0[Elf_r_sym(relp)];
char const *symname = &str0[w(symp->st_name)];
char const *mcount = gpfx == '_' ? "_mcount" : "mcount";
+ char const *fentry = "__fentry__";

if (symname[0] == '.')
++symname; /* ppc64 hack */
if (strcmp(mcount, symname) == 0 ||
- (altmcount && strcmp(altmcount, symname) == 0))
+ (altmcount && strcmp(altmcount, symname) == 0) ||
+ (strcmp(fentry, symname) == 0))
mcountsym = Elf_r_sym(relp);

return mcountsym;

\
 
 \ /
  Last update: 2012-08-27 20:21    [W:0.153 / U:0.484 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site