summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
Diffstat (limited to 'include')
-rw-r--r--include/linux/perf_event.h28
-rw-r--r--include/uapi/linux/perf_event.h3
2 files changed, 27 insertions, 4 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index b8b195fbe787..85749ae8cb5f 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -834,14 +834,24 @@ extern int perf_event_overflow(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs);
+extern void perf_event_output_forward(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs);
+extern void perf_event_output_backward(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs);
extern void perf_event_output(struct perf_event *event,
- struct perf_sample_data *data,
- struct pt_regs *regs);
+ struct perf_sample_data *data,
+ struct pt_regs *regs);
static inline bool
is_default_overflow_handler(struct perf_event *event)
{
- return (event->overflow_handler == perf_event_output);
+ if (likely(event->overflow_handler == perf_event_output_forward))
+ return true;
+ if (unlikely(event->overflow_handler == perf_event_output_backward))
+ return true;
+ return false;
}
extern void
@@ -1051,8 +1061,20 @@ static inline bool has_aux(struct perf_event *event)
return event->pmu->setup_aux;
}
+static inline bool is_write_backward(struct perf_event *event)
+{
+ return !!event->attr.write_backward;
+}
+
extern int perf_output_begin(struct perf_output_handle *handle,
struct perf_event *event, unsigned int size);
+extern int perf_output_begin_forward(struct perf_output_handle *handle,
+ struct perf_event *event,
+ unsigned int size);
+extern int perf_output_begin_backward(struct perf_output_handle *handle,
+ struct perf_event *event,
+ unsigned int size);
+
extern void perf_output_end(struct perf_output_handle *handle);
extern unsigned int perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len);
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index a3c19034d5f8..43fc8d213472 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -340,7 +340,8 @@ struct perf_event_attr {
comm_exec : 1, /* flag comm events that are due to an exec */
use_clockid : 1, /* use @clockid for time fields */
context_switch : 1, /* context switch data */
- __reserved_1 : 37;
+ write_backward : 1, /* Write ring buffer from end to beginning */
+ __reserved_1 : 36;
union {
__u32 wakeup_events; /* wakeup every n events */