summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
Diffstat (limited to 'include')
-rw-r--r--include/linux/perf_event.h12
-rw-r--r--include/uapi/linux/perf_event.h8
2 files changed, 19 insertions, 1 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 547773f5894e..68e21e828893 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -93,14 +93,26 @@ struct perf_raw_record {
/*
* branch stack layout:
* nr: number of taken branches stored in entries[]
+ * hw_idx: The low level index of raw branch records
+ * for the most recent branch.
+ * -1ULL means invalid/unknown.
*
* Note that nr can vary from sample to sample
* branches (to, from) are stored from most recent
* to least recent, i.e., entries[0] contains the most
* recent branch.
+ * The entries[] is an abstraction of raw branch records,
+ * which may not be stored in age order in HW, e.g. Intel LBR.
+ * The hw_idx is to expose the low level index of raw
+ * branch record for the most recent branch aka entries[0].
+ * The hw_idx index is between -1 (unknown) and max depth,
+ * which can be retrieved in /sys/devices/cpu/caps/branches.
+ * For the architectures whose raw branch records are
+ * already stored in age order, the hw_idx should be 0.
*/
struct perf_branch_stack {
__u64 nr;
+ __u64 hw_idx;
struct perf_branch_entry entries[0];
};
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 377d794d3105..397cfd65b3fe 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -181,6 +181,8 @@ enum perf_branch_sample_type_shift {
PERF_SAMPLE_BRANCH_TYPE_SAVE_SHIFT = 16, /* save branch type */
+ PERF_SAMPLE_BRANCH_HW_INDEX_SHIFT = 17, /* save low level index of raw branch records */
+
PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */
};
@@ -208,6 +210,8 @@ enum perf_branch_sample_type {
PERF_SAMPLE_BRANCH_TYPE_SAVE =
1U << PERF_SAMPLE_BRANCH_TYPE_SAVE_SHIFT,
+ PERF_SAMPLE_BRANCH_HW_INDEX = 1U << PERF_SAMPLE_BRANCH_HW_INDEX_SHIFT,
+
PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT,
};
@@ -853,7 +857,9 @@ enum perf_event_type {
* char data[size];}&& PERF_SAMPLE_RAW
*
* { u64 nr;
- * { u64 from, to, flags } lbr[nr];} && PERF_SAMPLE_BRANCH_STACK
+ * { u64 hw_idx; } && PERF_SAMPLE_BRANCH_HW_INDEX
+ * { u64 from, to, flags } lbr[nr];
+ * } && PERF_SAMPLE_BRANCH_STACK
*
* { u64 abi; # enum perf_sample_regs_abi
* u64 regs[weight(mask)]; } && PERF_SAMPLE_REGS_USER