diff options
| author | Wu Zhangjin <wuzhangjin@gmail.com> | 2009-11-20 20:34:35 +0800 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2009-12-17 01:57:25 +0000 |
| commit | e17ff5fec65a0213416efbe7ceae5f2f9887dda2 (patch) | |
| tree | 9f315fcacb075e4e1828fd9e0bd2133e11ec47b2 /arch/mips/kernel/ftrace.c | |
| parent | 29c5d3462f7c8f17bb9e0a29f0a299036468074d (diff) | |
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/ftrace.c')
| -rw-r--r-- | arch/mips/kernel/ftrace.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c index 65a3f8a8992..e981a497c98 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -115,6 +115,27 @@ int __init ftrace_dyn_arch_init(void *data) #ifdef CONFIG_FUNCTION_GRAPH_TRACER +#ifdef CONFIG_DYNAMIC_FTRACE + +extern void ftrace_graph_call(void); +#define JMP 0x08000000 /* jump to target directly */ +#define CALL_FTRACE_GRAPH_CALLER \ + jump_insn_encode(JMP, (unsigned long)(&ftrace_graph_caller)) +#define FTRACE_GRAPH_CALL_IP ((unsigned long)(&ftrace_graph_call)) + +int ftrace_enable_ftrace_graph_caller(void) +{ + return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, + CALL_FTRACE_GRAPH_CALLER); +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, ftrace_nop); +} + +#endif /* !CONFIG_DYNAMIC_FTRACE */ + #define S_RA_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */ #define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */ #define OFFSET_MASK 0xffff /* stack offset range: 0 ~ PT_SIZE */ |