diff mbox series

[v4,5/5] libtraceevent: Add tep_print_selected_fields()

Message ID 20210810122659.145759-6-y.karadz@gmail.com (mailing list archive)
State Superseded
Headers show
Series libtraceevent: Optimize the print of tep fields | expand

Commit Message

Yordan Karadzhov Aug. 10, 2021, 12:26 p.m. UTC
The new method can print only a subset of the unique data fields of
the trace event. The print format is derived from the parsing tokens
(tep_print_parse objects) of the event.

Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com>
---
 src/event-parse.c | 18 ++++++++++++++----
 src/event-parse.h |  3 +++
 2 files changed, 17 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/src/event-parse.c b/src/event-parse.c
index c7043ec..bc03daf 100644
--- a/src/event-parse.c
+++ b/src/event-parse.c
@@ -5453,20 +5453,30 @@  void tep_print_field(struct trace_seq *s, void *data,
 	_tep_print_field(s, data, field, NULL);
 }
 
-void tep_print_fields(struct trace_seq *s, void *data,
-		      int size __maybe_unused, struct tep_event *event)
+void tep_print_selected_fields(struct trace_seq *s, void *data,
+			       struct tep_event *event,
+			       int ignore_mask)
 {
 	struct tep_print_parse *parse = event->print_fmt.print_cache;
 	struct tep_format_field *field;
+	int field_mask = 1;
 
 	field = event->format.fields;
-	while (field) {
+	for (;field; field = field->next, field_mask *= 2) {
+		if (field_mask & ignore_mask)
+			continue;
+
 		trace_seq_printf(s, " %s=", field->name);
 		_tep_print_field(s, data, field, &parse);
-		field = field->next;
 	}
 }
 
+void tep_print_fields(struct trace_seq *s, void *data,
+		      int size __maybe_unused, struct tep_event *event)
+{
+	tep_print_selected_fields(s, data, event, 0);
+}
+
 static int print_function(struct trace_seq *s, const char *format,
 			  void *data, int size, struct tep_event *event,
 			  struct tep_print_arg *arg)
diff --git a/src/event-parse.h b/src/event-parse.h
index d4a876f..c8f3251 100644
--- a/src/event-parse.h
+++ b/src/event-parse.h
@@ -545,6 +545,9 @@  int tep_cmdline_pid(struct tep_handle *tep, struct tep_cmdline *cmdline);
 
 void tep_print_field(struct trace_seq *s, void *data,
 		     struct tep_format_field *field);
+void tep_print_selected_fields(struct trace_seq *s, void *data,
+			       struct tep_event *event,
+			       int ignore_mask);
 void tep_print_fields(struct trace_seq *s, void *data,
 		      int size __maybe_unused, struct tep_event *event);
 int tep_strerror(struct tep_handle *tep, enum tep_errno errnum,