[PATCH v2 2/4] perf script: Add --time-filter option

[Namhyung Kim <namhyung@kernel.org>]

From: Namhyung Kim <namhyung.kim@lge.com>

The --time-filter option is for limiting samples within a range of
time.  A time range looks like <time1>-<time2> and at most one of them
can be omitted.  For instance:

  $ perf script --time-filter -2178446.12
  ...
         xchat  1772 [002] 2178446.070330: sched:sched_switch: prev_comm=xchat prev_pid=177
       swapper     0 [002] 2178446.070338: power:cpu_idle: state=4 cpu_id=2
       swapper     0 [001] 2178446.091952: sched:sched_wakeup: comm=synergys pid=1488 prio=
       swapper     0 [001] 2178446.091958: power:cpu_idle: state=4294967295 cpu_id=1
       swapper     0 [001] 2178446.091970: sched:sched_switch: prev_comm=swapper/1 prev_pid
      synergys  1488 [001] 2178446.091995: sched:sched_switch: prev_comm=synergys prev_pid=
       swapper     0 [001] 2178446.092003: power:cpu_idle: state=4 cpu_id=1
       swapper     0 [001] 2178446.116997: sched:sched_wakeup: comm=synergys pid=1488 prio=
       swapper     0 [001] 2178446.117004: power:cpu_idle: state=4294967295 cpu_id=1
       swapper     0 [001] 2178446.117016: sched:sched_switch: prev_comm=swapper/1 prev_pid
      synergys  1488 [001] 2178446.117040: sched:sched_switch: prev_comm=synergys prev_pid=
       swapper     0 [001] 2178446.117048: power:cpu_idle: state=4 cpu_id=1

Above example only displays samples which have a timestamp before
2178446.120000.

Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/Documentation/perf-script.txt |  7 +++++++
 tools/perf/builtin-script.c              | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index e9cbfcddfa3f..c4994c5f27ff 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -203,6 +203,13 @@ OPTIONS
 --show-kernel-path::
 	Try to resolve the path of [kernel.kallsyms]
 
+-X::
+--time-filter::
+	Display samples within a range of time only. A time range can be given
+	like 'time1-time2' and treated as a start time and end time
+        respectively. The time format is like "<sec>.<usec>". Either of time1
+	or time2 can be omitted.
+
 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 92d4658f56fb..d598765e59cb 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -28,6 +28,13 @@ static bool			system_wide;
 static const char		*cpu_list;
 static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 
+struct time_range {
+	u64 start;
+	u64 end;
+};
+
+static struct time_range trange;
+
 enum perf_output_field {
 	PERF_OUTPUT_COMM            = 1U << 0,
 	PERF_OUTPUT_TID             = 1U << 1,
@@ -510,6 +517,12 @@ static int process_sample_event(struct perf_tool *tool __maybe_unused,
 	if (cpu_list && !test_bit(sample->cpu, cpu_bitmap))
 		return 0;
 
+	if (trange.start && trange.start > sample->time)
+		return 0;
+
+	if (trange.end && trange.end < sample->time)
+		return 0;
+
 	scripting_ops->process_event(event, sample, evsel, machine, &al);
 
 	evsel->hists.stats.total_period += sample->period;
@@ -1236,6 +1249,23 @@ static int have_cmd(int argc, const char **argv)
 	return 0;
 }
 
+static int
+parse_time_filter(const struct option *opt, const char *str,
+		  int unset __maybe_unused)
+{
+	struct time_range *time_range = opt->value;
+	char *sep = strchr(str, '-');
+
+	if (sep == NULL)
+		return parse_nsec_time(str, &time_range->start);
+	else if (sep == str)
+		return parse_nsec_time(++str, &time_range->end);
+
+	*sep++ = '\0';
+	return parse_nsec_time(str, &time_range->start) ||
+		parse_nsec_time(sep, &time_range->end);
+}
+
 int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	bool show_full_info = false;
@@ -1286,6 +1316,8 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
 		    "display extended information from perf.data file"),
 	OPT_BOOLEAN('\0', "show-kernel-path", &symbol_conf.show_kernel_path,
 		    "Show the path of [kernel.kallsyms]"),
+	OPT_CALLBACK('X', "time-filter", &trange, "time[-time]",
+		     "Only display entries in the time range", parse_time_filter),
 	OPT_END()
 	};
 	const char * const script_usage[] = {
-- 
1.7.11.7