tests/xe_evict|exec_threads: Use fd reopen to avoid corrupting global data

Device scanning and filtering was designed to work in multi-process
environment. Due to that opening the device with drm_open_driver()
in multiple threads lead to global device data corruption.

At the moment there's no easy way to redesign this so simplest thing
we may do is to just acquire device fd in main process and reopen it
(this doesn't involve any device scanning) in spawned threads.

Lets use drm_reopen_driver() to stop calling not thread-safe code.

Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Reviewed-by: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Link: https://lore.kernel.org/r/20240422144713.76025-1-zbigniew.kempczynski@intel.com
Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>

2 files changed, 13 insertions, 19 deletions

diff --git a/tests/intel/xe_evict.c b/tests/intel/xe_evict.c
index 8ef55211f..5994ebb14 100644
--- a/tests/intel/xe_evict.c
+++ b/tests/intel/xe_evict.c
@@ -61,7 +61,7 @@ test_evict(int fd, struct drm_xe_engine_class_instance *eci,
 	bo = calloc(n_execs / 2, sizeof(*bo));
 	igt_assert(bo);
 
-	fd = drm_open_driver(DRIVER_XE);
+	fd = drm_reopen_driver(fd);
 
 	vm = xe_vm_create(fd, 0, 0);
 	if (flags & BIND_EXEC_QUEUE)
@@ -241,7 +241,7 @@ test_evict_cm(int fd, struct drm_xe_engine_class_instance *eci,
 	bo = calloc(n_execs / 2, sizeof(*bo));
 	igt_assert(bo);
 
-	fd = drm_open_driver(DRIVER_XE);
+	fd = drm_reopen_driver(fd);
 
 	vm = xe_vm_create(fd, DRM_XE_VM_CREATE_FLAG_LR_MODE, 0);
 	if (flags & BIND_EXEC_QUEUE)
@@ -769,21 +769,21 @@ igt_main
 
 	for (const struct section *s = sections; s->name; s++) {
 		igt_subtest_f("evict-%s", s->name)
-			test_evict(-1, hwe, s->n_exec_queues, s->n_execs,
+			test_evict(fd, hwe, s->n_exec_queues, s->n_execs,
 				   calc_bo_size(vram_size, s->mul, s->div),
 				   s->flags, NULL);
 	}
 
 	for (const struct section_cm *s = sections_cm; s->name; s++) {
 		igt_subtest_f("evict-%s", s->name)
-			test_evict_cm(-1, hwe, s->n_exec_queues, s->n_execs,
+			test_evict_cm(fd, hwe, s->n_exec_queues, s->n_execs,
 				      calc_bo_size(vram_size, s->mul, s->div),
 				      s->flags, NULL);
 	}
 
 	for (const struct section_threads *s = sections_threads; s->name; s++) {
 		igt_subtest_f("evict-%s", s->name)
-			threads(-1, hwe, s->n_threads, s->n_exec_queues,
+			threads(fd, hwe, s->n_threads, s->n_exec_queues,
 				 s->n_execs,
 				 calc_bo_size(vram_size, s->mul, s->div),
 				 s->flags);
diff --git a/tests/intel/xe_exec_threads.c b/tests/intel/xe_exec_threads.c
index 8083980f9..1e80842b9 100644
--- a/tests/intel/xe_exec_threads.c
+++ b/tests/intel/xe_exec_threads.c
@@ -71,8 +71,8 @@ test_balancer(int fd, int gt, uint32_t vm, uint64_t addr, uint64_t userptr,
 
 	igt_assert(n_exec_queues <= MAX_N_EXEC_QUEUES);
 
-	if (!fd) {
-		fd = drm_open_driver(DRIVER_XE);
+	if (flags & FD) {
+		fd = drm_reopen_driver(fd);
 		owns_fd = true;
 	}
 
@@ -273,8 +273,8 @@ test_compute_mode(int fd, uint32_t vm, uint64_t addr, uint64_t userptr,
 
 	igt_assert(n_exec_queues <= MAX_N_EXEC_QUEUES);
 
-	if (!fd) {
-		fd = drm_open_driver(DRIVER_XE);
+	if (flags & FD) {
+		fd = drm_reopen_driver(fd);
 		owns_fd = true;
 	}
 
@@ -477,8 +477,8 @@ test_legacy_mode(int fd, uint32_t vm, uint64_t addr, uint64_t userptr,
 
 	igt_assert(n_exec_queues <= MAX_N_EXEC_QUEUES);
 
-	if (!fd) {
-		fd = drm_open_driver(DRIVER_XE);
+	if (flags & FD) {
+		fd = drm_reopen_driver(fd);
 		owns_fd = true;
 	}
 
@@ -995,10 +995,7 @@ static void threads(int fd, int flags)
 #define ADDRESS_SHIFT	39
 		threads_data[i].addr = addr | (i << ADDRESS_SHIFT);
 		threads_data[i].userptr = userptr | (i << ADDRESS_SHIFT);
-		if (flags & FD)
-			threads_data[i].fd = 0;
-		else
-			threads_data[i].fd = fd;
+		threads_data[i].fd = fd;
 		threads_data[i].vm_legacy_mode = vm_legacy_mode;
 		threads_data[i].vm_compute_mode = vm_compute_mode;
 		threads_data[i].eci = hwe;
@@ -1046,10 +1043,7 @@ static void threads(int fd, int flags)
 						threads_data[i].addr = addr;
 					threads_data[i].userptr = userptr |
 						(i << ADDRESS_SHIFT);
-					if (flags & FD)
-						threads_data[i].fd = 0;
-					else
-						threads_data[i].fd = fd;
+					threads_data[i].fd = fd;
 					threads_data[i].gt = gt;
 					threads_data[i].vm_legacy_mode =
 						vm_legacy_mode;