lib/core: Handle asserts in threads

Since IGT is using magic control blocks (igt_subtest et al.) asserts
jump out the them using longjmp() causing a bunch of confusing messages
and occasionally crashing the whole process.

This is not the behavior we want :-)

With this patch:

1. simple_main, dynamic and subtest each clears the thread failure state
   at the start

2. each of those blocks also asserts no thread failures at the end

3. igt_assert() in non-main thread prints out the error + stacktrace
   and marks that we have failed thread

Issue: https://gitlab.freedesktop.org/drm/igt-gpu-tools/-/issues/55
Signed-off-by: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Reviewed-by: Petri Latvala <petri.latvala@intel.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/lib/igt_thread.c b/lib/igt_thread.c
index deab62257..5bdda4102 100644
--- a/lib/igt_thread.c
+++ b/lib/igt_thread.c
@@ -22,12 +22,42 @@
  */
 
 #include <pthread.h>
+#include <stdlib.h>
+#include <stdatomic.h>
 
 #include "igt_core.h"
 #include "igt_thread.h"
 
 static pthread_key_t __igt_is_main_thread;
 
+static _Atomic(bool) __thread_failed = false;
+
+void igt_thread_clear_fail_state(void)
+{
+	assert(igt_thread_is_main());
+
+	__thread_failed = false;
+}
+
+void igt_thread_fail(void)
+{
+	assert(!igt_thread_is_main());
+
+	__thread_failed = true;
+}
+
+void igt_thread_assert_no_failures(void)
+{
+	assert(igt_thread_is_main());
+
+	if (__thread_failed) {
+		/* so we won't get stuck in a loop */
+		igt_thread_clear_fail_state();
+		igt_critical("Failure in a thread!\n");
+		igt_fail(IGT_EXIT_FAILURE);
+	}
+}
+
 bool igt_thread_is_main(void)
 {
 	return pthread_getspecific(__igt_is_main_thread) != NULL;