[PATCH AUTOSEL 6.12 3/4] rtla/timerlat_hist: Abort event processing on second signal

[Sasha Levin <sashal@kernel.org>]

From: Tomas Glozar <tglozar@redhat.com>

[ Upstream commit d6899e560366e10141189697502bc5521940c588 ]

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/20250116144931.649593-5-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/tracing/rtla/src/timerlat_hist.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index 2cc3ffcbc983d..8dc33e1e6aed2 100644
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -1139,6 +1139,14 @@ static struct osnoise_tool
 static int stop_tracing;
 static void stop_hist(int sig)
 {
+	if (stop_tracing) {
+		/*
+		 * Stop requested twice in a row; abort event processing and
+		 * exit immediately
+		 */
+		tracefs_iterate_stop(hist_inst->inst);
+		return;
+	}
 	stop_tracing = 1;
 }
 
-- 
2.39.5