[PATCH v2 3/6] perf script: Add option to specify time window of interest

[David Ahern <dsa@cumulusnetworks.com>]

Add option to allow user to control analysis window. e.g., collect data
for some amount of time and analyze a segment of interest within that
window.

Signed-off-by: David Ahern <dsahern@gmail.com>
---
 tools/perf/Documentation/perf-script.txt |  7 +++++++
 tools/perf/builtin-script.c              | 15 ++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index 0f6ee09f7256..5dc5c6a09ac4 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -292,6 +292,13 @@ include::itrace.txt[]
 --force::
 	Don't do ownership validation.
 
+--time::
+	Only analyze samples within given time window: <start>,<stop>. Times
+	have the format seconds.microseconds. If start is not given (i.e., time
+	string is ',x.y') then analysis starts at the beginning of the file. If
+	stop time is not given (i.e, time string is 'x.y,') then analysis goes
+	to end of file.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-script-perl[1],
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 066b4bf73780..2f3ff69fc4e7 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -22,6 +22,7 @@
 #include "util/thread_map.h"
 #include "util/stat.h"
 #include "util/thread-stack.h"
+#include "util/time-utils.h"
 #include <linux/bitmap.h>
 #include <linux/stringify.h>
 #include <linux/time64.h>
@@ -833,6 +834,8 @@ struct perf_script {
 	struct cpu_map		*cpus;
 	struct thread_map	*threads;
 	int			name_width;
+	const char              *time_str;
+	struct perf_time_interval ptime;
 };
 
 static int perf_evlist__max_name_len(struct perf_evlist *evlist)
@@ -1014,6 +1017,9 @@ static int process_sample_event(struct perf_tool *tool,
 	struct perf_script *scr = container_of(tool, struct perf_script, tool);
 	struct addr_location al;
 
+	if (perf_time__skip_sample(&scr->ptime, sample->time))
+		return 0;
+
 	if (debug_mode) {
 		if (sample->time < last_timestamp) {
 			pr_err("Samples misordered, previous: %" PRIu64
@@ -2186,7 +2192,8 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 			"Enable symbol demangling"),
 	OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
 			"Enable kernel symbol demangling"),
-
+	OPT_STRING(0, "time", &script.time_str, "str",
+		   "Time span of interest (start,stop)"),
 	OPT_END()
 	};
 	const char * const script_subcommands[] = { "record", "report", NULL };
@@ -2465,6 +2472,12 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 	if (err < 0)
 		goto out_delete;
 
+	/* needs to be parsed after looking up reference time */
+	if (perf_time__parse_str(&script.ptime, script.time_str) != 0) {
+		pr_err("Invalid time string\n");
+		return -EINVAL;
+	}
+
 	err = __cmd_script(&script);
 
 	flush_scripting();
-- 
2.7.4 (Apple Git-66)