diff options
| author | Wu Zhangjin <wuzhangjin@gmail.com> | 2009-11-20 13:34:35 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2009-12-17 02:57:25 +0100 |
| commit | e17ff5fec65a0213416efbe7ceae5f2f9887dda2 (patch) | |
| tree | 9f315fcacb075e4e1828fd9e0bd2133e11ec47b2 /arch/mips/kernel/mcount.S | |
| parent | MIPS: Tracing: Add function graph tracer support for MIPS (diff) | |
| download | linux-e17ff5fec65a0213416efbe7ceae5f2f9887dda2.tar.xz linux-e17ff5fec65a0213416efbe7ceae5f2f9887dda2.zip | |
MIPS: Tracing: Add dynamic function graph tracer for MIPS
This patch make function graph tracer work with dynamic function tracer.
To share the source code of dynamic function tracer(MCOUNT_SAVE_REGS),
and avoid restoring the whole saved registers, we need to restore the ra
register from the stack.
(NOTE: This not work with 32bit! need to ensure why!)
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/678/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/mcount.S')
| -rw-r--r-- | arch/mips/kernel/mcount.S | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S index b50e38d828c4..98d469032506 100644 --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -77,6 +77,13 @@ ftrace_call: nop /* a placeholder for the call to a real tracing function */ move a1, AT /* arg2: the caller's next ip, parent */ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + .globl ftrace_graph_call +ftrace_graph_call: + nop + nop +#endif + MCOUNT_RESTORE_REGS .globl ftrace_stub ftrace_stub: @@ -124,10 +131,13 @@ ftrace_stub: #ifdef CONFIG_FUNCTION_GRAPH_TRACER NESTED(ftrace_graph_caller, PT_SIZE, ra) +#ifdef CONFIG_DYNAMIC_FTRACE + PTR_L a1, PT_R31(sp) /* load the original ra from the stack */ +#else MCOUNT_SAVE_REGS - - PTR_LA a0, PT_R1(sp) /* arg1: &AT -> a0 */ move a1, ra /* arg2: next ip, selfaddr */ +#endif + PTR_LA a0, PT_R1(sp) /* arg1: &AT -> a0 */ jal prepare_ftrace_return move a2, fp /* arg3: frame pointer */ |