i915/gem_exec_schedule: Rebuild signal handler in child

Make sure that the SIGARLM handler is captured so that we don't
accidentally shoot ourselves in the foot instead of merely waking up the
execbuf.

The test is hitting

	child 0 died with signal 14, Alarm clock

when we expect it to be hitting the inherited signal handler across the
fork. Which is odd.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

1 files changed, 13 insertions, 6 deletions

diff --git a/tests/i915/gem_exec_schedule.c b/tests/i915/gem_exec_schedule.c
index 0462ce84..d11e5736 100644
--- a/tests/i915/gem_exec_schedule.c
+++ b/tests/i915/gem_exec_schedule.c
@@ -1087,6 +1087,7 @@ static void test_pi_ringfull(int fd, unsigned int engine)
 	unsigned int last, count;
 	struct itimerval itv;
 	IGT_CORK_HANDLE(c);
+	uint32_t vip;
 	bool *result;
 
 	result = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
@@ -1101,9 +1102,16 @@ static void test_pi_ringfull(int fd, unsigned int engine)
 	execbuf.buffers_ptr = to_user_pointer(&obj[1]);
 	execbuf.buffer_count = 1;
 	execbuf.flags = engine;
+
+	/* Warm up both (hi/lo) contexts */
 	execbuf.rsvd1 = gem_context_create(fd);
-	gem_context_set_priority(fd, execbuf.rsvd1, MIN_PRIO);
+	gem_context_set_priority(fd, execbuf.rsvd1, MAX_PRIO);
+	gem_execbuf(fd, &execbuf);
+	gem_sync(fd, obj[1].handle);
+	vip = execbuf.rsvd1;
 
+	execbuf.rsvd1 = gem_context_create(fd);
+	gem_context_set_priority(fd, execbuf.rsvd1, MIN_PRIO);
 	gem_execbuf(fd, &execbuf);
 	gem_sync(fd, obj[1].handle);
 
@@ -1147,14 +1155,12 @@ static void test_pi_ringfull(int fd, unsigned int engine)
 	igt_fork(child, 1) {
 		result[0] = true;
 
-		igt_debug("Creating HP context\n");
-		execbuf.rsvd1 = gem_context_create(fd);
-		gem_context_set_priority(fd, execbuf.rsvd1, MAX_PRIO);
-
+		igt_debug("Waking parent\n");
 		kill(getppid(), SIGALRM);
 		sched_yield();
 		result[1] = true;
 
+		sigaction(SIGALRM, &sa, NULL);
 		itv.it_value.tv_sec = 0;
 		itv.it_value.tv_usec = 10000;
 		setitimer(ITIMER_REAL, &itv, NULL);
@@ -1163,8 +1169,8 @@ static void test_pi_ringfull(int fd, unsigned int engine)
 		 * able to add ourselves to *our* ring without interruption.
 		 */
 		igt_debug("HP child executing\n");
+		execbuf.rsvd1 = vip;
 		result[2] = __execbuf(fd, &execbuf) == 0;
-		gem_context_destroy(fd, execbuf.rsvd1);
 	}
 
 	/* Relinquish CPU just to allow child to create a context */
@@ -1186,6 +1192,7 @@ static void test_pi_ringfull(int fd, unsigned int engine)
 	igt_waitchildren();
 
 	gem_context_destroy(fd, execbuf.rsvd1);
+	gem_context_destroy(fd, vip);
 	gem_close(fd, obj[1].handle);
 	gem_close(fd, obj[0].handle);
 	munmap(result, 4096);