[igt-dev] [PATCH i-g-t] lib: Make sure we leak no child processes

Daniel Vetter
2019-02-11T22:43:23Z

There's a lot more ways to leak children than igt_fork, some even
handrolled. So check for that. Also have a nice littel testcase for
that too.

v2: Don't hang if there's a leaked child process (Chris). Has the
added benefit that my library unit test also gets faster!

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
---
lib/igt_core.c | 4 ++++
lib/tests/igt_fork.c | 18 ++++++++++++++++++
2 files changed, 22 insertions(+)

diff --git a/lib/igt_core.c b/lib/igt_core.c
index 3053697da58c..d2cfc8e6da20 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -1492,6 +1492,8 @@ void __igt_fail_assert(const char *domain, const char *file, const int line,
*/
void igt_exit(void)
{
+ int tmp;
+
igt_exit_called = true;

if (igt_key_file)
@@ -1527,6 +1529,8 @@ void igt_exit(void)
kill(test_children[c], SIGKILL);
assert(!num_test_children);

+ assert(waitpid(-1, &tmp, WNOHANG) == -1 && errno == ECHILD);
+
if (!test_with_subtests) {
struct timespec now;
const char *result;
diff --git a/lib/tests/igt_fork.c b/lib/tests/igt_fork.c
index e5b0ab016b23..b486d07000bb 100644
--- a/lib/tests/igt_fork.c
+++ b/lib/tests/igt_fork.c
@@ -68,6 +68,20 @@ static void igt_fork_leak(void)
}
}

+static void plain_fork_leak(void)
+{
+ int pid;
+
+ switch (pid = fork()) {
+ case -1:
+ internal_assert(0);
+ case 0:
+ sleep(1);
+ default:
+ exit(0);
+ }
+}
+
static void igt_fork_timeout_leak(void)
{
igt_fork(i, 1) {
@@ -122,4 +136,8 @@ int main(int argc, char **argv)
/* check that igt_waitchildren_timeout cleans up*/
ret = do_fork(igt_fork_timeout_leak);
internal_assert(ret == IGT_EXIT_FAILURE);
+
+ /* check that any other process leaks are caught*/
+ ret = do_fork(plain_fork_leak);
+ internal_assert(ret == SIGABRT + 128);
}
--
2.20.1