perf evsel: Cache associated event_format

We already lookup the associated event_format when reading the perf.data
header, so that we can cache the tracepoint name in evsel->name, so do
it a little further and save the event_format itself, so that we can
avoid relookups in tools that need to access it.

Change the tools to take the most obvious advantage, when they were
using pevent_find_event directly. More work is needed for further
removing the need of a pointer to pevent, such as when asking for event
field values ("common_pid" and the other common fields and per
event_format fields).

This is something that was planned but only got actually done when
Andrey Wagin needed to do this lookup at perf_tool->sample() time, when
we don't have access to pevent (session->pevent) to use with
pevent_find_event().

Cc: Andrey Wagin <avagin@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/tip-txkvew2ckko0b594ae8fbnyk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/scripting-engines/trace-event-perl.c b/tools/perf/util/scripting-engines/trace-event-perl.c
index 02dfa19..c266281 100644
--- a/tools/perf/util/scripting-engines/trace-event-perl.c
+++ b/tools/perf/util/scripting-engines/trace-event-perl.c
@@ -237,16 +237,16 @@
 		define_event_symbols(event, ev_name, args->next);
 }
 
-static inline
-struct event_format *find_cache_event(struct pevent *pevent, int type)
+static inline struct event_format *find_cache_event(struct perf_evsel *evsel)
 {
 	static char ev_name[256];
 	struct event_format *event;
+	int type = evsel->attr.config;
 
 	if (events[type])
 		return events[type];
 
-	events[type] = event = pevent_find_event(pevent, type);
+	events[type] = event = evsel->tp_format;
 	if (!event)
 		return NULL;
 
@@ -269,7 +269,6 @@
 	unsigned long long val;
 	unsigned long s, ns;
 	struct event_format *event;
-	int type;
 	int pid;
 	int cpu = sample->cpu;
 	void *data = sample->raw_data;
@@ -281,11 +280,9 @@
 	if (evsel->attr.type != PERF_TYPE_TRACEPOINT)
 		return;
 
-	type = trace_parse_common_type(pevent, data);
-
-	event = find_cache_event(pevent, type);
+	event = find_cache_event(evsel);
 	if (!event)
-		die("ug! no event found for type %d", type);
+		die("ug! no event found for type %d", evsel->attr.config);
 
 	pid = trace_parse_common_pid(pevent, data);