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linux/arch/microblaze/include/asm/ftrace.h

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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>
2009-11-16 01:40:14 -07:00
#ifndef _ASM_MICROBLAZE_FTRACE
#define _ASM_MICROBLAZE_FTRACE
microblaze: Add missing empty ftrace.h file Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-04-13 23:37:30 -07:00
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>
2009-11-16 01:40:14 -07:00
#ifdef CONFIG_FUNCTION_TRACER
#define MCOUNT_ADDR ((long)(_mcount))
#define MCOUNT_INSN_SIZE 8 /* sizeof mcount call */
#ifndef __ASSEMBLY__
extern void _mcount(void);
extern void ftrace_call_graph(void);
#endif
microblaze: ftrace: Add dynamic trace support With dynamic function tracer, by default, _mcount is defined as an "empty" function, it returns directly without any more action. When enabling it in user-space, it will jump to a real tracing function(ftrace_caller), and do the real job for us. Differ from the static function tracer, dynamic function tracer provides two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the tracing of some indicated kernel functions(set_ftrace_filter). In the kernel version, there is only one "_mcount" string for every kernel function, so, we just need to match this one in mcount_regex of scripts/recordmcount.pl. For more information please look at code and Documentation/trace folder. Steven ACK that scripts/recordmcount.pl part. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-12-10 06:15:44 -07:00
#ifdef CONFIG_DYNAMIC_FTRACE
/* reloction of mcount call site is the same as the address */
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
return addr;
}
struct dyn_arch_ftrace {
};
#endif /* CONFIG_DYNAMIC_FTRACE */
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>
2009-11-16 01:40:14 -07:00
#endif /* CONFIG_FUNCTION_TRACER */
#endif /* _ASM_MICROBLAZE_FTRACE */
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