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| author | Michal Simek <monstr@monstr.eu> | 2009-11-16 09:40:14 +0100 |
|---|---|---|
| committer | Michal Simek <monstr@monstr.eu> | 2009-12-14 08:40:09 +0100 |
| commit | 2fd7c761a24c28e83d7194b4b4a099451126a503 (patch) | |
| tree | c8647ae1bc4519649e35e46b231f3f2af77f9a76 /arch/microblaze/kernel/microblaze_ksyms.c | |
| parent | a3cd613b2e775eb59816c2c7c49c038d54917208 (diff) | |
| download | linux-2fd7c761a24c28e83d7194b4b4a099451126a503.tar.bz2 | |
microblaze: ftrace: add static function tracer
If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to
_mcount will be inserted into each kernel function. so, there is a
possibility to trace the kernel functions in _mcount.
This patch add the specific _mcount support for static function
tracing. by default, ftrace_trace_function is initialized as
ftrace_stub(an empty function), so, the default _mcount will introduce
very little overhead. after enabling ftrace in user-space, it will jump
to a real tracing function and do static function tracing for us.
Commit message from Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
Diffstat (limited to 'arch/microblaze/kernel/microblaze_ksyms.c')
| -rw-r--r-- | arch/microblaze/kernel/microblaze_ksyms.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/microblaze/kernel/microblaze_ksyms.c b/arch/microblaze/kernel/microblaze_ksyms.c index 59ff20e33e0c..bc4dcb7d3861 100644 --- a/arch/microblaze/kernel/microblaze_ksyms.c +++ b/arch/microblaze/kernel/microblaze_ksyms.c @@ -18,6 +18,7 @@ #include <linux/io.h> #include <asm/page.h> #include <asm/system.h> +#include <linux/ftrace.h> #include <linux/uaccess.h> /* @@ -47,3 +48,7 @@ extern void __umodsi3(void); EXPORT_SYMBOL(__umodsi3); extern char *_ebss; EXPORT_SYMBOL_GPL(_ebss); +#ifdef CONFIG_FUNCTION_TRACER +extern void _mcount(void); +EXPORT_SYMBOL(_mcount); +#endif |