[V2,3/6] perf: Support branch events
Commit Message
From: Kan Liang <kan.liang@linux.intel.com>
With the cycle time information between branches, stalls can be easily
observed. But it's difficult to explain what causes the long delay.
Add a new branch sample type to indicate whether include occurrences of
events in branch info. The information will be stored in the branch
stack extension space.
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
---
Changes since V1:
- Rename to PERF_SAMPLE_BRANCH_EVT_CNTRS
- Drop the event ID sample type
include/linux/perf_event.h | 4 ++++
include/uapi/linux/perf_event.h | 4 ++++
2 files changed, 8 insertions(+)
@@ -1137,6 +1137,10 @@ static inline bool branch_sample_priv(const struct perf_event *event)
return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_PRIV_SAVE;
}
+static inline bool branch_sample_evt_cntrs(const struct perf_event *event)
+{
+ return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_EVT_CNTRS;
+}
struct perf_sample_data {
/*
@@ -204,6 +204,8 @@ enum perf_branch_sample_type_shift {
PERF_SAMPLE_BRANCH_PRIV_SAVE_SHIFT = 18, /* save privilege mode */
+ PERF_SAMPLE_BRANCH_EVT_CNTRS_SHIFT = 19, /* save occurrences of events on a branch */
+
PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */
};
@@ -235,6 +237,8 @@ enum perf_branch_sample_type {
PERF_SAMPLE_BRANCH_PRIV_SAVE = 1U << PERF_SAMPLE_BRANCH_PRIV_SAVE_SHIFT,
+ PERF_SAMPLE_BRANCH_EVT_CNTRS = 1U << PERF_SAMPLE_BRANCH_EVT_CNTRS_SHIFT,
+
PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT,
};