perf: Allow for custom overflow handlers
in-kernel perf users might wish to have custom actions on the
sample interrupt.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.222339539@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index b5cdac0..a430ac3 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -567,6 +567,8 @@
typedef void (*perf_callback_t)(struct perf_event *, void *);
+struct perf_sample_data;
+
/**
* struct perf_event - performance event kernel representation:
*/
@@ -658,6 +660,10 @@
struct pid_namespace *ns;
u64 id;
+ void (*overflow_handler)(struct perf_event *event,
+ int nmi, struct perf_sample_data *data,
+ struct pt_regs *regs);
+
#ifdef CONFIG_EVENT_PROFILE
struct event_filter *filter;
#endif
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 3852e26..1dfb6cc 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -3710,7 +3710,11 @@
perf_event_disable(event);
}
- perf_event_output(event, nmi, data, regs);
+ if (event->overflow_handler)
+ event->overflow_handler(event, nmi, data, regs);
+ else
+ perf_event_output(event, nmi, data, regs);
+
return ret;
}
@@ -4836,6 +4840,8 @@
if (parent_event->attr.freq)
child_event->hw.sample_period = parent_event->hw.sample_period;
+ child_event->overflow_handler = parent_event->overflow_handler;
+
/*
* Link it up in the child's context:
*/
