[tip:perf/core] perf pmu: Support per pmu json aliases

[tip-bot for Andi Kleen]

Commit-ID:  15b22ed369aa23ef4d083ffb9621650c353d3ddd
Gitweb:     http://git.kernel.org/tip/15b22ed369aa23ef4d083ffb9621650c353d3ddd
Author:     Andi Kleen <ak@xxxxxxxxxxxxxxx>
AuthorDate: Fri, 27 Jan 2017 18:03:38 -0800
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 8 Feb 2017 08:55:03 -0300

perf pmu: Support per pmu json aliases

Add support for registering json aliases per PMU. Any alias with an unit
matching the prefix is registered to the PMU.  Uncore has multiple
instances of most units, so all these aliases get registered for each
individual PMU (this is important later to run the event on every
instance of the PMU).

To avoid printing the events multiple times in perf list filter out
duplicated events during printing.

v2: Rely on uncore_ prefix already in unit
v3: Document why calls were reordered

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170128020345.19007-4-andi@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/pmu.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 6dc3cc0..8e9d00f 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -590,14 +590,16 @@ static struct perf_pmu *pmu_lookup(const char *name)
 	if (pmu_format(name, &format))
 		return NULL;
 
-	if (pmu_aliases(name, &aliases))
+	/*
+	 * Check the type first to avoid unnecessary work.
+	 */
+	if (pmu_type(name, &type))
 		return NULL;
 
-	pmu_add_cpu_aliases(&aliases, name);
-
-	if (pmu_type(name, &type))
+	if (pmu_aliases(name, &aliases))
 		return NULL;
 
+	pmu_add_cpu_aliases(&aliases, name);
 	pmu = zalloc(sizeof(*pmu));
 	if (!pmu)
 		return NULL;
@@ -1195,6 +1197,9 @@ void print_pmu_events(const char *event_glob, bool name_only, bool quiet_flag,
 	len = j;
 	qsort(aliases, len, sizeof(struct sevent), cmp_sevent);
 	for (j = 0; j < len; j++) {
+		/* Skip duplicates */
+		if (j > 0 && !strcmp(aliases[j].name, aliases[j - 1].name))
+			continue;
 		if (name_only) {
 			printf("%s ", aliases[j].name);
 			continue;