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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 08:40:14 +00:00
#ifndef _ASM_MICROBLAZE_FTRACE
#define _ASM_MICROBLAZE_FTRACE
microblaze: Add missing empty ftrace.h file Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-04-14 06:37:30 +00:00
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 08:40:14 +00:00
#ifdef CONFIG_FUNCTION_TRACER
ftrace: Format MCOUNT_ADDR address as type unsigned long Always we use type unsigned long to format the ip address, since the value of ip address is never the negative. This patch uses type unsigned long, instead of long, to format the ip address. The code is more clearly to be viewed by using type unsigned long, although it is correct by using either unsigned long or long. Link: http://lkml.kernel.org/r/1436694744-16747-1-git-send-email-mhuang@redhat.com Cc: Minfei Huang <mnfhuang@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Minfei Huang <mnfhuang@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-07-12 09:52:24 +00:00
#define MCOUNT_ADDR ((unsigned long)(_mcount))
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 08:40:14 +00:00
#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 13:15:44 +00:00
#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 08:40:14 +00:00
#endif /* CONFIG_FUNCTION_TRACER */
#endif /* _ASM_MICROBLAZE_FTRACE */
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