[igt-dev] [PATCH i-g-t 3/9] lib: Don't leak children in igt_waitchildren_timeout

Daniel Vetter
2019-02-11T18:02:20Z

Instead of cleaning up the mess in igt_exit make sure we don't even
let it out of the container. See also

commit 754876378d6c9b2775e8c07b4d16f9878c55949f
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri Feb 26 22:11:10 2016 +0000

igt/gem_sync: Enforce a timeout of 20s

which added this helper.

To make sure that everyone follows the rules, add an assert.

We're keeping the cleanup code as a failsafe, and because it speeds
up the testcase I'm following up with.

v2: Chris pointed out that my original patch did nothing. Which I
didn't catch because my testcase was also broken. Unfortunately this
means we need to open code part of the waiting.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
---
lib/igt_core.c | 39 ++++++++++++++++++++++++++++++++++-----
1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/lib/igt_core.c b/lib/igt_core.c
index cbbe79f88070..3053697da58c 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -1525,6 +1525,7 @@ void igt_exit(void)

for (int c = 0; c < num_test_children; c++)
kill(test_children[c], SIGKILL);
+ assert(!num_test_children);

if (!test_with_subtests) {
struct timespec now;
@@ -1832,20 +1833,48 @@ void igt_waitchildren(void)
igt_fail(err);
}

+static bool igt_killchidren_timed_out;
+
+static void igt_alarm_killchildren(int signal)
+{
+ igt_info("Timed out waiting for children\n");
+
+ igt_killchidren_timed_out = true;
+
+ for (int c = 0; c < num_test_children; c++)
+ kill(test_children[c], SIGKILL);
+}
+
/**
* igt_waitchildren_timeout:
* @seconds: timeout in seconds to wait
* @reason: debug string explaining what timedout
*
- * Wait for all children forked with igt_fork, for a maximum of @seconds.
- *
- * Wraps igt_waitchildren() and igt_set_timeout()
+ * Wait for all children forked with igt_fork, for a maximum of @seconds. If the
+ * timeout expires, kills all children and cleans them up.
*/
void igt_waitchildren_timeout(int seconds, const char *reason)
{
- igt_set_timeout(seconds, reason);
- igt_waitchildren();
+ struct sigaction sa;
+ int ret;
+
+ sa.sa_handler = igt_alarm_killchildren;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+
+ igt_killchidren_timed_out = false;
+
+ sigaction(SIGALRM, &sa, NULL);
+
+ alarm(seconds);
+
+ ret = __igt_waitchildren();
+ if (!igt_killchidren_timed_out && ret)
+ igt_fail(ret);
igt_reset_timeout();
+ __igt_waitchildren();
+ if (igt_killchidren_timed_out)
+ igt_fail(IGT_EXIT_FAILURE);
}

/* exit handler code */
--
2.20.1