[PATCH 22/27] perf db-export: Add trace begin / end branch type variants

From: Arnaldo Carvalho de Melo
Date: Mon Sep 24 2018 - 11:05:16 EST


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

Add branch types to cover different combinations with "trace begin" or
"trace end".

Previously, the Intel PT decoder would indicate begin / end by a branch
from / to zero. That hides useful information, in particular when a
trace ends with a call. Before remedying that, prepare the database
export to export branch types with more combinations that include trace
begin / end. In those cases extend the descriptions to include 'trace
begin' and 'trace end' separately.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20180920130048.31432-3-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/db-export.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/tools/perf/util/db-export.c b/tools/perf/util/db-export.c
index 7123746edcf4..69fbb0a72d0c 100644
--- a/tools/perf/util/db-export.c
+++ b/tools/perf/util/db-export.c
@@ -463,6 +463,28 @@ int db_export__branch_types(struct db_export *dbe)
if (err)
break;
}
+
+ /* Add trace begin / end variants */
+ for (i = 0; branch_types[i].name ; i++) {
+ const char *name = branch_types[i].name;
+ u32 type = branch_types[i].branch_type;
+ char buf[64];
+
+ if (type == PERF_IP_FLAG_BRANCH ||
+ (type & (PERF_IP_FLAG_TRACE_BEGIN | PERF_IP_FLAG_TRACE_END)))
+ continue;
+
+ snprintf(buf, sizeof(buf), "trace begin / %s", name);
+ err = db_export__branch_type(dbe, type | PERF_IP_FLAG_TRACE_BEGIN, buf);
+ if (err)
+ break;
+
+ snprintf(buf, sizeof(buf), "%s / trace end", name);
+ err = db_export__branch_type(dbe, type | PERF_IP_FLAG_TRACE_END, buf);
+ if (err)
+ break;
+ }
+
return err;
}

--
2.14.4