rtla/timerlat_top: Abort event processing on second signal

If either SIGINT is received twice, or after a SIGALRM (that is, after
timerlat was supposed to stop), abort processing events currently left
in the tracefs buffer and exit immediately.

This allows the user to exit rtla without waiting for processing all
events, should that take longer than wanted, at the cost of not
processing all samples.

Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/20250116144931.649593-6-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index d21a21053917e2dbf2fb44610899b722b9caf297..d358cd39f3604ef83aa5a315dc1f00543c84693b 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -903,6 +903,14 @@ static int stop_tracing;
 static struct trace_instance *top_inst = NULL;
 static void stop_top(int sig)
 {
+       if (stop_tracing) {
+               /*
+                * Stop requested twice in a row; abort event processing and
+                * exit immediately
+                */
+               tracefs_iterate_stop(top_inst->inst);
+               return;
+       }
        stop_tracing = 1;
        if (top_inst)
                trace_instance_stop(top_inst);