linux/arch/sh/lib/mcount.S
Matt Fleming fad57feba7 sh: dynamic ftrace support.
First cut at dynamic ftrace support.

Signed-off-by: Matt Fleming <mjf@gentoo.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:42:52 +09:00

90 lines
1.6 KiB
ArmAsm

/*
* arch/sh/lib/mcount.S
*
* Copyright (C) 2008 Paul Mundt
* Copyright (C) 2008 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
* for more details.
*/
#include <asm/ftrace.h>
#define MCOUNT_ENTER() \
mov.l r4, @-r15; \
mov.l r5, @-r15; \
mov.l r6, @-r15; \
mov.l r7, @-r15; \
sts.l pr, @-r15; \
\
mov.l @(20,r15),r4; \
sts pr, r5
#define MCOUNT_LEAVE() \
lds.l @r15+, pr; \
mov.l @r15+, r7; \
mov.l @r15+, r6; \
mov.l @r15+, r5; \
rts; \
mov.l @r15+, r4
.align 2
.globl _mcount
.type _mcount,@function
.globl mcount
.type mcount,@function
_mcount:
mcount:
MCOUNT_ENTER()
#ifdef CONFIG_DYNAMIC_FTRACE
.globl mcount_call
mcount_call:
mov.l .Lftrace_stub, r6
#else
mov.l .Lftrace_trace_function, r6
mov.l ftrace_stub, r7
cmp/eq r6, r7
bt skip_trace
mov.l @r6, r6
#endif
jsr @r6
nop
skip_trace:
MCOUNT_LEAVE()
.align 2
.Lftrace_trace_function:
.long ftrace_trace_function
#ifdef CONFIG_DYNAMIC_FTRACE
.globl ftrace_caller
ftrace_caller:
MCOUNT_ENTER()
.globl ftrace_call
ftrace_call:
mov.l .Lftrace_stub, r6
jsr @r6
nop
MCOUNT_LEAVE()
#endif /* CONFIG_DYNAMIC_FTRACE */
/*
* NOTE: From here on the locations of the .Lftrace_stub label and
* ftrace_stub itself are fixed. Adding additional data here will skew
* the displacement for the memory table and break the block replacement.
* Place new labels either after the ftrace_stub body, or before
* ftrace_caller. You have been warned.
*/
.align 2
.Lftrace_stub:
.long ftrace_stub
.globl ftrace_stub
ftrace_stub:
rts
nop