sh: Define HAVE_FUNCTION_TRACE_MCOUNT_TEST
Enable HAVE_FUNCTION_TRACE_MCOUNT_TEST and test the value of
function_trace_stop from our assembly code as opposed to using the
generic C function. This should optimise our mcount/ftrace code path.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index e2bdd7b..801a4a7 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -31,6 +31,7 @@
select HAVE_FUNCTION_TRACER
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
+ select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_ARCH_KGDB
select ARCH_HIBERNATION_POSSIBLE if MMU
diff --git a/arch/sh/lib/mcount.S b/arch/sh/lib/mcount.S
index 110fbfe..cb87ef5 100644
--- a/arch/sh/lib/mcount.S
+++ b/arch/sh/lib/mcount.S
@@ -2,7 +2,7 @@
* arch/sh/lib/mcount.S
*
* Copyright (C) 2008 Paul Mundt
- * Copyright (C) 2008 Matt Fleming
+ * Copyright (C) 2008, 2009 Matt Fleming
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
@@ -35,6 +35,12 @@
.type mcount,@function
_mcount:
mcount:
+#ifndef CONFIG_DYNAMIC_FTRACE
+ mov.l .Lfunction_trace_stop, r0
+ mov.l @r0, r0
+ tst r0, r0
+ bf ftrace_stub
+#endif
MCOUNT_ENTER()
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -62,6 +68,11 @@
#ifdef CONFIG_DYNAMIC_FTRACE
.globl ftrace_caller
ftrace_caller:
+ mov.l .Lfunction_trace_stop, r0
+ mov.l @r0, r0
+ tst r0, r0
+ bf ftrace_stub
+
MCOUNT_ENTER()
.globl ftrace_call
@@ -88,3 +99,7 @@
ftrace_stub:
rts
nop
+
+ .align 2
+.Lfunction_trace_stop:
+ .long function_trace_stop