perf tools: Add a per tracepoint counter attribute to get raw sample

Add a new flag field while opening a tracepoint perf counter:

-e tracepoint_subsystem:tracepoint_name:flags

This is intended to be generic although for now it only supports the
r[e[c[o[r[d]]]]] flag:

./perf record -e workqueue:workqueue_insertion:record
./perf record -e workqueue:workqueue_insertion:r

will have the same effect: enabling the raw samples record for
the given tracepoint counter.

In the future, we may want to support further flags, separated
by commas.

Signed-off-by: Frederic Weisbecker <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Mike Galbraith <[e-mail]>
LKML-Reference: <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>

tools/perf/builtin-record.c

···
 				  PERF_FORMAT_TOTAL_TIME_RUNNING |
 				  PERF_FORMAT_ID;
 
-	attr->sample_type	= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
+	attr->sample_type	|= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 
 	if (freq) {
 		attr->sample_type	|= PERF_SAMPLE_PERIOD;

tools/perf/util/parse-events.c

···
 				    struct perf_counter_attr *attr)
 {
 	const char *evt_name;
+	char *flags;
 	char sys_name[MAX_EVENT_LENGTH];
 	char id_buf[4];
 	int fd;
···
 	strncpy(sys_name, *strp, sys_length);
 	sys_name[sys_length] = '\0';
 	evt_name = evt_name + 1;
+
+	flags = strchr(evt_name, ':');
+	if (flags) {
+		*flags = '\0';
+		flags++;
+		if (!strncmp(flags, "record", strlen(flags)))
+			attr->sample_type |= PERF_SAMPLE_RAW;
+	}
+
 	evt_length = strlen(evt_name);
 	if (evt_length >= MAX_EVENT_LENGTH)
 		return 0;