[PATCH v2 05/11] perf script: Add not taken event for branch stack
Leo Yan
leo.yan at arm.com
Fri Feb 14 03:19:30 PST 2025
The branch stack has an existed field for printing mispredict, extend
the field for printing events and add support not-taken event.
Reviewed-by: Ian Rogers <irogers at google.com>
Signed-off-by: Leo Yan <leo.yan at arm.com>
---
tools/perf/builtin-script.c | 20 +++++++++++++-------
tools/perf/util/branch.h | 3 ++-
2 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 2c4b1fb7dc72..43bf327bb72b 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -935,19 +935,25 @@ static int perf_sample__fprintf_start(struct perf_script *script,
return printed;
}
-static inline char
-mispred_str(struct branch_entry *br)
+static inline size_t
+bstack_event_str(struct branch_entry *br, char *buf, size_t sz)
{
- if (!(br->flags.mispred || br->flags.predicted))
- return '-';
+ if (!(br->flags.mispred || br->flags.predicted || br->flags.not_taken))
+ return snprintf(buf, sz, "-");
- return br->flags.predicted ? 'P' : 'M';
+ return snprintf(buf, sz, "%s%s",
+ br->flags.predicted ? "P" : "M",
+ br->flags.not_taken ? "N" : "");
}
static int print_bstack_flags(FILE *fp, struct branch_entry *br)
{
- return fprintf(fp, "/%c/%c/%c/%d/%s/%s ",
- mispred_str(br),
+ char events[16] = { 0 };
+ size_t pos;
+
+ pos = bstack_event_str(br, events, sizeof(events));
+ return fprintf(fp, "/%s/%c/%c/%d/%s/%s ",
+ pos < 0 ? "-" : events,
br->flags.in_tx ? 'X' : '-',
br->flags.abort ? 'A' : '-',
br->flags.cycles,
diff --git a/tools/perf/util/branch.h b/tools/perf/util/branch.h
index b80c12c74bbb..7429530fa774 100644
--- a/tools/perf/util/branch.h
+++ b/tools/perf/util/branch.h
@@ -25,7 +25,8 @@ struct branch_flags {
u64 spec:2;
u64 new_type:4;
u64 priv:3;
- u64 reserved:31;
+ u64 not_taken:1;
+ u64 reserved:30;
};
};
};
--
2.34.1
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