tools/rv: Do not skip idle in trace

Currently, the userspace RV tool skips trace events triggered by the RV
tool itself, this can be changed by passing the parameter -s, which sets
the variable config_my_pid to 0 (instead of the tool's PID).
This has the side effect of skipping events generated by idle (PID 0).

Set config_my_pid to -1 (an invalid pid) to avoid skipping idle.

Cc: Nam Cao <[email protected]>
Cc: Tomas Glozar <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: John Kacur <[email protected]>
Link: https://lore.kernel.org/[email protected]
Fixes: 6d60f89691 ("tools/rv: Add in-kernel monitor interface")
Signed-off-by: Gabriele Monaco <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

tools/verification/rv/src/in_kernel.c

@@ -431,7 +431,7 @@ ikm_event_handler(struct trace_seq *s, struct tep_record *record,
 
 	if (config_has_id && (config_my_pid == id))
 		return 0;
-	else if (config_my_pid && (config_my_pid == pid))
+	else if (config_my_pid == pid)
 		return 0;
 
 	tep_print_event(trace_event->tep, s, record, "%16s-%-8d [%.3d] ",
@@ -734,7 +734,7 @@ static int parse_arguments(char *monitor_name, int argc, char **argv)
 			config_reactor = optarg;
 			break;
 		case 's':
-			config_my_pid = 0;
+			config_my_pid = -1;
 			break;
 		case 't':
 			config_trace = 1;