Commit ac199db0 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

ftrace: event profile hooks



Impact: new tracing infrastructure feature

Provide infrastructure to generate software perf counter events
from tracepoints.
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090319194233.557364871@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 28bea271
......@@ -44,5 +44,6 @@ obj-$(CONFIG_EVENT_TRACER) += trace_events.o
obj-$(CONFIG_EVENT_TRACER) += events.o
obj-$(CONFIG_EVENT_TRACER) += trace_export.o
obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o
obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o
libftrace-y := ftrace.o
......@@ -12,4 +12,3 @@
#include "trace_events_stage_2.h"
#include "trace_events_stage_3.h"
#include <trace/trace_event_types.h>
......@@ -785,12 +785,23 @@ struct ftrace_event_call {
int id;
int (*raw_init)(void);
int (*show_format)(struct trace_seq *s);
#ifdef CONFIG_EVENT_PROFILE
atomic_t profile_count;
int (*profile_enable)(struct ftrace_event_call *);
void (*profile_disable)(struct ftrace_event_call *);
#endif
};
void event_trace_printk(unsigned long ip, const char *fmt, ...);
extern struct ftrace_event_call __start_ftrace_events[];
extern struct ftrace_event_call __stop_ftrace_events[];
#define for_each_event(event) \
for (event = __start_ftrace_events; \
(unsigned long)event < (unsigned long)__stop_ftrace_events; \
event++)
extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];
......
/*
* trace event based perf counter profiling
*
* Copyright (C) 2009 Red Hat Inc, Peter Zijlstra <pzijlstr@redhat.com>
*
*/
#include "trace.h"
int ftrace_profile_enable(int event_id)
{
struct ftrace_event_call *event;
for_each_event(event) {
if (event->id == event_id)
return event->profile_enable(event);
}
return -EINVAL;
}
void ftrace_profile_disable(int event_id)
{
struct ftrace_event_call *event;
for_each_event(event) {
if (event->id == event_id)
return event->profile_disable(event);
}
}
......@@ -19,11 +19,6 @@
static DEFINE_MUTEX(event_mutex);
#define events_for_each(event) \
for (event = __start_ftrace_events; \
(unsigned long)event < (unsigned long)__stop_ftrace_events; \
event++)
static void ftrace_clear_events(void)
{
struct ftrace_event_call *call = (void *)__start_ftrace_events;
......@@ -90,7 +85,7 @@ static int ftrace_set_clr_event(char *buf, int set)
}
mutex_lock(&event_mutex);
events_for_each(call) {
for_each_event(call) {
if (!call->name || !call->regfunc)
continue;
......@@ -628,7 +623,7 @@ static __init int event_trace_init(void)
if (!d_events)
return 0;
events_for_each(call) {
for_each_event(call) {
/* The linker may leave blanks */
if (!call->name)
continue;
......
......@@ -109,6 +109,40 @@
#undef TP_FMT
#define TP_FMT(fmt, args...) fmt "\n", ##args
#ifdef CONFIG_EVENT_PROFILE
#define _TRACE_PROFILE(call, proto, args) \
static void ftrace_profile_##call(proto) \
{ \
extern void perf_tpcounter_event(int); \
perf_tpcounter_event(event_##call.id); \
} \
\
static int ftrace_profile_enable_##call(struct ftrace_event_call *call) \
{ \
int ret = 0; \
\
if (!atomic_inc_return(&call->profile_count)) \
ret = register_trace_##call(ftrace_profile_##call); \
\
return ret; \
} \
\
static void ftrace_profile_disable_##call(struct ftrace_event_call *call) \
{ \
if (atomic_add_negative(-1, &call->profile_count)) \
unregister_trace_##call(ftrace_profile_##call); \
}
#define _TRACE_PROFILE_INIT(call) \
.profile_count = ATOMIC_INIT(-1), \
.profile_enable = ftrace_profile_enable_##call, \
.profile_disable = ftrace_profile_disable_##call,
#else
#define _TRACE_PROFILE(call, proto, args)
#define _TRACE_PROFILE_INIT(call)
#endif
#define _TRACE_FORMAT(call, proto, args, fmt) \
static void ftrace_event_##call(proto) \
{ \
......@@ -147,6 +181,7 @@ static int ftrace_init_event_##call(void) \
#undef TRACE_FORMAT
#define TRACE_FORMAT(call, proto, args, fmt) \
_TRACE_FORMAT(call, PARAMS(proto), PARAMS(args), PARAMS(fmt)) \
_TRACE_PROFILE(call, PARAMS(proto), PARAMS(args)) \
static struct ftrace_event_call __used \
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
......@@ -155,6 +190,7 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
.raw_init = ftrace_init_event_##call, \
.regfunc = ftrace_reg_event_##call, \
.unregfunc = ftrace_unreg_event_##call, \
_TRACE_PROFILE_INIT(call) \
}
#undef __entry
......@@ -162,6 +198,7 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
_TRACE_PROFILE(call, PARAMS(proto), PARAMS(args)) \
\
static struct ftrace_event_call event_##call; \
\
......@@ -227,4 +264,11 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
.regfunc = ftrace_raw_reg_event_##call, \
.unregfunc = ftrace_raw_unreg_event_##call, \
.show_format = ftrace_format_##call, \
_TRACE_PROFILE_INIT(call) \
}
#include <trace/trace_event_types.h>
#undef _TRACE_PROFILE
#undef _TRACE_PROFILE_INIT
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