drm/i915/selftests: Allow for larger engine counts

Increasing the engine count causes a couple of local array variables
to exceed the kernel stack limit. So make them dynamic allocations
instead.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721223043.834562-8-matthew.d.roper@intel.com

drivers/gpu/drm/i915/gt/selftest_execlists.c

@@ -3561,20 +3561,24 @@ static int smoke_crescendo(struct preempt_smoke *smoke, unsigned int flags)
 #define BATCH BIT(0)
 {
 	struct task_struct *tsk[I915_NUM_ENGINES] = {};
-	struct preempt_smoke arg[I915_NUM_ENGINES];
+	struct preempt_smoke *arg;
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
 	unsigned long count;
 	int err = 0;
 
+	arg = kmalloc_array(I915_NUM_ENGINES, sizeof(*arg), GFP_KERNEL);
+	if (!arg)
+		return -ENOMEM;
+
 	for_each_engine(engine, smoke->gt, id) {
 		arg[id] = *smoke;
 		arg[id].engine = engine;
 		if (!(flags & BATCH))
 			arg[id].batch = NULL;
 		arg[id].count = 0;
 
-		tsk[id] = kthread_run(smoke_crescendo_thread, &arg,
+		tsk[id] = kthread_run(smoke_crescendo_thread, arg,
 				      "igt/smoke:%d", id);
 		if (IS_ERR(tsk[id])) {
 			err = PTR_ERR(tsk[id]);
@@ -3603,6 +3607,8 @@ static int smoke_crescendo(struct preempt_smoke *smoke, unsigned int flags)
 
 	pr_info("Submitted %lu crescendo:%x requests across %d engines and %d contexts\n",
 		count, flags, smoke->gt->info.num_engines, smoke->ncontext);
+
+	kfree(arg);
 	return 0;
 }
 

drivers/gpu/drm/i915/gt/selftest_workarounds.c

@@ -1175,31 +1175,36 @@ live_gpu_reset_workarounds(void *arg)
 {
 	struct intel_gt *gt = arg;
 	intel_wakeref_t wakeref;
-	struct wa_lists lists;
+	struct wa_lists *lists;
 	bool ok;
 
 	if (!intel_has_gpu_reset(gt))
 		return 0;
 
+	lists = kzalloc(sizeof(*lists), GFP_KERNEL);
+	if (!lists)
+		return -ENOMEM;
+
 	pr_info("Verifying after GPU reset...\n");
 
 	igt_global_reset_lock(gt);
 	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
 
-	reference_lists_init(gt, &lists);
+	reference_lists_init(gt, lists);
 
-	ok = verify_wa_lists(gt, &lists, "before reset");
+	ok = verify_wa_lists(gt, lists, "before reset");
 	if (!ok)
 		goto out;
 
 	intel_gt_reset(gt, ALL_ENGINES, "live_workarounds");
 
-	ok = verify_wa_lists(gt, &lists, "after reset");
+	ok = verify_wa_lists(gt, lists, "after reset");
 
 out:
-	reference_lists_fini(gt, &lists);
+	reference_lists_fini(gt, lists);
 	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
 	igt_global_reset_unlock(gt);
+	kfree(lists);
 
 	return ok ? 0 : -ESRCH;
 }
@@ -1214,16 +1219,20 @@ live_engine_reset_workarounds(void *arg)
 	struct igt_spinner spin;
 	struct i915_request *rq;
 	intel_wakeref_t wakeref;
-	struct wa_lists lists;
+	struct wa_lists *lists;
 	int ret = 0;
 
 	if (!intel_has_reset_engine(gt))
 		return 0;
 
+	lists = kzalloc(sizeof(*lists), GFP_KERNEL);
+	if (!lists)
+		return -ENOMEM;
+
 	igt_global_reset_lock(gt);
 	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
 
-	reference_lists_init(gt, &lists);
+	reference_lists_init(gt, lists);
 
 	for_each_engine(engine, gt, id) {
 		bool ok;
@@ -1235,7 +1244,7 @@ live_engine_reset_workarounds(void *arg)
 			break;
 		}
 
-		ok = verify_wa_lists(gt, &lists, "before reset");
+		ok = verify_wa_lists(gt, lists, "before reset");
 		if (!ok) {
 			ret = -ESRCH;
 			goto err;
@@ -1247,7 +1256,7 @@ live_engine_reset_workarounds(void *arg)
 			goto err;
 		}
 
-		ok = verify_wa_lists(gt, &lists, "after idle reset");
+		ok = verify_wa_lists(gt, lists, "after idle reset");
 		if (!ok) {
 			ret = -ESRCH;
 			goto err;
@@ -1282,7 +1291,7 @@ live_engine_reset_workarounds(void *arg)
 		igt_spinner_end(&spin);
 		igt_spinner_fini(&spin);
 
-		ok = verify_wa_lists(gt, &lists, "after busy reset");
+		ok = verify_wa_lists(gt, lists, "after busy reset");
 		if (!ok) {
 			ret = -ESRCH;
 			goto err;
@@ -1294,9 +1303,10 @@ live_engine_reset_workarounds(void *arg)
 			break;
 	}
 
-	reference_lists_fini(gt, &lists);
+	reference_lists_fini(gt, lists);
 	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
 	igt_global_reset_unlock(gt);
+	kfree(lists);
 
 	igt_flush_test(gt->i915);