[PATCH 3/3] perf list: Support filtering in JSON output

[Namhyung Kim <namhyung@kernel.org>]

Like regular output mode, it should honor command line arguments to
limit to a certain type of PMUs or events.

  $ perf list -j hw
  [
  {
          "Unit": "cpu",
          "Topic": "legacy hardware",
          "EventName": "branch-instructions",
          "EventType": "Kernel PMU event",
          "BriefDescription": "Retired branch instructions [This event is an alias of branches]",
          "Encoding": "cpu/event=0xc4\n/"
  },
  {
          "Unit": "cpu",
          "Topic": "legacy hardware",
          "EventName": "branch-misses",
          "EventType": "Kernel PMU event",
          "BriefDescription": "Mispredicted branch instructions",
          "Encoding": "cpu/event=0xc5\n/"
  },
  ...

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-list.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tools/perf/builtin-list.c b/tools/perf/builtin-list.c
index 1ab969ffe371c5cb..48c799007414bf6e 100644
--- a/tools/perf/builtin-list.c
+++ b/tools/perf/builtin-list.c
@@ -375,6 +375,21 @@ static void json_print_event(void *ps, const char *topic,
 	FILE *fp = print_state->fp;
 	struct strbuf buf;
 
+	if (deprecated && !print_state->deprecated)
+		return;
+
+	if (print_state->pmu_glob && (!pmu_name || !strglobmatch(pmu_name, print_state->pmu_glob)))
+		return;
+
+	if (print_state->exclude_abi && pmu_type < PERF_TYPE_MAX && pmu_type != PERF_TYPE_RAW)
+		return;
+
+	if (print_state->event_glob &&
+	    (!event_name || !strglobmatch(event_name, print_state->event_glob)) &&
+	    (!event_alias || !strglobmatch(event_alias, print_state->event_glob)) &&
+	    (!topic || !strglobmatch_nocase(topic, print_state->event_glob)))
+		return;
+
 	strbuf_init(&buf, 0);
 	fprintf(fp, "%s{\n", print_state->need_sep ? ",\n" : "");
 	print_state->need_sep = true;
@@ -451,6 +466,11 @@ static void json_print_metric(void *ps __maybe_unused, const char *group,
 	FILE *fp = print_state->fp;
 	struct strbuf buf;
 
+	if (print_state->event_glob &&
+	    (!print_state->metrics || !name || !strglobmatch(name, print_state->event_glob)) &&
+	    (!print_state->metricgroups || !group || !strglobmatch(group, print_state->event_glob)))
+		return;
+
 	strbuf_init(&buf, 0);
 	fprintf(fp, "%s{\n", print_state->need_sep ? ",\n" : "");
 	print_state->need_sep = true;
-- 
2.52.0.rc1.455.g30608eb744-goog