ftrace, perf: Add open/close tracepoint perf registration actions

Adding TRACE_REG_PERF_OPEN and TRACE_REG_PERF_CLOSE to differentiate
register/unregister from open/close actions.

The register/unregister actions are invoked for the first/last
tracepoint user when opening/closing the event.

The open/close actions are invoked for each tracepoint user when
opening/closing the event.

Link: http://lkml.kernel.org/r/1329317514-8131-3-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Jiri Olsa 2012-02-15 15:51:49 +01:00 committed by Steven Rostedt
parent e248491ac2
commit ceec0b6fc7
5 changed files with 101 additions and 51 deletions

View file

@ -146,6 +146,8 @@ enum trace_reg {
TRACE_REG_UNREGISTER,
TRACE_REG_PERF_REGISTER,
TRACE_REG_PERF_UNREGISTER,
TRACE_REG_PERF_OPEN,
TRACE_REG_PERF_CLOSE,
};
struct ftrace_event_call;
@ -157,7 +159,7 @@ struct ftrace_event_class {
void *perf_probe;
#endif
int (*reg)(struct ftrace_event_call *event,
enum trace_reg type);
enum trace_reg type, void *data);
int (*define_fields)(struct ftrace_event_call *);
struct list_head *(*get_fields)(struct ftrace_event_call *);
struct list_head fields;
@ -165,7 +167,7 @@ struct ftrace_event_class {
};
extern int ftrace_event_reg(struct ftrace_event_call *event,
enum trace_reg type);
enum trace_reg type, void *data);
enum {
TRACE_EVENT_FL_ENABLED_BIT,

View file

@ -44,23 +44,17 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
return 0;
}
static int perf_trace_event_init(struct ftrace_event_call *tp_event,
struct perf_event *p_event)
static int perf_trace_event_reg(struct ftrace_event_call *tp_event,
struct perf_event *p_event)
{
struct hlist_head __percpu *list;
int ret;
int ret = -ENOMEM;
int cpu;
ret = perf_trace_event_perm(tp_event, p_event);
if (ret)
return ret;
p_event->tp_event = tp_event;
if (tp_event->perf_refcount++ > 0)
return 0;
ret = -ENOMEM;
list = alloc_percpu(struct hlist_head);
if (!list)
goto fail;
@ -83,7 +77,7 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
}
}
ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER);
ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER, NULL);
if (ret)
goto fail;
@ -108,6 +102,69 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
return ret;
}
static void perf_trace_event_unreg(struct perf_event *p_event)
{
struct ftrace_event_call *tp_event = p_event->tp_event;
int i;
if (--tp_event->perf_refcount > 0)
goto out;
tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER, NULL);
/*
* Ensure our callback won't be called anymore. The buffers
* will be freed after that.
*/
tracepoint_synchronize_unregister();
free_percpu(tp_event->perf_events);
tp_event->perf_events = NULL;
if (!--total_ref_count) {
for (i = 0; i < PERF_NR_CONTEXTS; i++) {
free_percpu(perf_trace_buf[i]);
perf_trace_buf[i] = NULL;
}
}
out:
module_put(tp_event->mod);
}
static int perf_trace_event_open(struct perf_event *p_event)
{
struct ftrace_event_call *tp_event = p_event->tp_event;
return tp_event->class->reg(tp_event, TRACE_REG_PERF_OPEN, p_event);
}
static void perf_trace_event_close(struct perf_event *p_event)
{
struct ftrace_event_call *tp_event = p_event->tp_event;
tp_event->class->reg(tp_event, TRACE_REG_PERF_CLOSE, p_event);
}
static int perf_trace_event_init(struct ftrace_event_call *tp_event,
struct perf_event *p_event)
{
int ret;
ret = perf_trace_event_perm(tp_event, p_event);
if (ret)
return ret;
ret = perf_trace_event_reg(tp_event, p_event);
if (ret)
return ret;
ret = perf_trace_event_open(p_event);
if (ret) {
perf_trace_event_unreg(p_event);
return ret;
}
return 0;
}
int perf_trace_init(struct perf_event *p_event)
{
struct ftrace_event_call *tp_event;
@ -130,6 +187,14 @@ int perf_trace_init(struct perf_event *p_event)
return ret;
}
void perf_trace_destroy(struct perf_event *p_event)
{
mutex_lock(&event_mutex);
perf_trace_event_close(p_event);
perf_trace_event_unreg(p_event);
mutex_unlock(&event_mutex);
}
int perf_trace_add(struct perf_event *p_event, int flags)
{
struct ftrace_event_call *tp_event = p_event->tp_event;
@ -154,37 +219,6 @@ void perf_trace_del(struct perf_event *p_event, int flags)
hlist_del_rcu(&p_event->hlist_entry);
}
void perf_trace_destroy(struct perf_event *p_event)
{
struct ftrace_event_call *tp_event = p_event->tp_event;
int i;
mutex_lock(&event_mutex);
if (--tp_event->perf_refcount > 0)
goto out;
tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER);
/*
* Ensure our callback won't be called anymore. The buffers
* will be freed after that.
*/
tracepoint_synchronize_unregister();
free_percpu(tp_event->perf_events);
tp_event->perf_events = NULL;
if (!--total_ref_count) {
for (i = 0; i < PERF_NR_CONTEXTS; i++) {
free_percpu(perf_trace_buf[i]);
perf_trace_buf[i] = NULL;
}
}
out:
module_put(tp_event->mod);
mutex_unlock(&event_mutex);
}
__kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
struct pt_regs *regs, int *rctxp)
{

View file

@ -147,7 +147,8 @@ int trace_event_raw_init(struct ftrace_event_call *call)
}
EXPORT_SYMBOL_GPL(trace_event_raw_init);
int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
int ftrace_event_reg(struct ftrace_event_call *call,
enum trace_reg type, void *data)
{
switch (type) {
case TRACE_REG_REGISTER:
@ -170,6 +171,9 @@ int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
call->class->perf_probe,
call);
return 0;
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
return 0;
#endif
}
return 0;
@ -209,7 +213,7 @@ static int ftrace_event_enable_disable(struct ftrace_event_call *call,
tracing_stop_cmdline_record();
call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
}
call->class->reg(call, TRACE_REG_UNREGISTER);
call->class->reg(call, TRACE_REG_UNREGISTER, NULL);
}
break;
case 1:
@ -218,7 +222,7 @@ static int ftrace_event_enable_disable(struct ftrace_event_call *call,
tracing_start_cmdline_record();
call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
}
ret = call->class->reg(call, TRACE_REG_REGISTER);
ret = call->class->reg(call, TRACE_REG_REGISTER, NULL);
if (ret) {
tracing_stop_cmdline_record();
pr_info("event trace: Could not enable event "

View file

@ -1892,7 +1892,8 @@ static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
#endif /* CONFIG_PERF_EVENTS */
static __kprobes
int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
int kprobe_register(struct ftrace_event_call *event,
enum trace_reg type, void *data)
{
struct trace_probe *tp = (struct trace_probe *)event->data;
@ -1909,6 +1910,9 @@ int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
case TRACE_REG_PERF_UNREGISTER:
disable_trace_probe(tp, TP_FLAG_PROFILE);
return 0;
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
return 0;
#endif
}
return 0;

View file

@ -17,9 +17,9 @@ static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
static int syscall_enter_register(struct ftrace_event_call *event,
enum trace_reg type);
enum trace_reg type, void *data);
static int syscall_exit_register(struct ftrace_event_call *event,
enum trace_reg type);
enum trace_reg type, void *data);
static int syscall_enter_define_fields(struct ftrace_event_call *call);
static int syscall_exit_define_fields(struct ftrace_event_call *call);
@ -649,7 +649,7 @@ void perf_sysexit_disable(struct ftrace_event_call *call)
#endif /* CONFIG_PERF_EVENTS */
static int syscall_enter_register(struct ftrace_event_call *event,
enum trace_reg type)
enum trace_reg type, void *data)
{
switch (type) {
case TRACE_REG_REGISTER:
@ -664,13 +664,16 @@ static int syscall_enter_register(struct ftrace_event_call *event,
case TRACE_REG_PERF_UNREGISTER:
perf_sysenter_disable(event);
return 0;
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
return 0;
#endif
}
return 0;
}
static int syscall_exit_register(struct ftrace_event_call *event,
enum trace_reg type)
enum trace_reg type, void *data)
{
switch (type) {
case TRACE_REG_REGISTER:
@ -685,6 +688,9 @@ static int syscall_exit_register(struct ftrace_event_call *event,
case TRACE_REG_PERF_UNREGISTER:
perf_sysexit_disable(event);
return 0;
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
return 0;
#endif
}
return 0;