drm/i915: Drop struct_mutex from around i915_retire_requests()

We don't need to hold struct_mutex now for retiring requests, so drop it
from i915_retire_requests() and i915_gem_wait_for_idle(), finally
removing I915_WAIT_LOCKED for good.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-8-chris@chris-wilson.co.uk

1 files changed, 15 insertions, 74 deletions

diff --git a/drivers/gpu/drm/i915/gt/selftest_hangcheck.c b/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
index d3bee9f88008..ffbb3d23b887 100644
--- a/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
+++ b/drivers/gpu/drm/i915/gt/selftest_hangcheck.c
@@ -58,7 +58,9 @@ static int hang_init(struct hang *h, struct intel_gt *gt)
 	memset(h, 0, sizeof(*h));
 	h->gt = gt;
 
+	mutex_lock(&gt->i915->drm.struct_mutex);
 	h->ctx = kernel_context(gt->i915);
+	mutex_unlock(&gt->i915->drm.struct_mutex);
 	if (IS_ERR(h->ctx))
 		return PTR_ERR(h->ctx);
 
@@ -285,7 +287,7 @@ static void hang_fini(struct hang *h)
 
 	kernel_context_close(h->ctx);
 
-	igt_flush_test(h->gt->i915, I915_WAIT_LOCKED);
+	igt_flush_test(h->gt->i915);
 }
 
 static bool wait_until_running(struct hang *h, struct i915_request *rq)
@@ -309,10 +311,9 @@ static int igt_hang_sanitycheck(void *arg)
 
 	/* Basic check that we can execute our hanging batch */
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
 	err = hang_init(&h, gt);
 	if (err)
-		goto unlock;
+		return err;
 
 	for_each_engine(engine, gt->i915, id) {
 		struct intel_wedge_me w;
@@ -355,8 +356,6 @@ static int igt_hang_sanitycheck(void *arg)
 
 fini:
 	hang_fini(&h);
-unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
 	return err;
 }
 
@@ -395,8 +394,6 @@ static int igt_reset_nop(void *arg)
 	reset_count = i915_reset_count(global);
 	count = 0;
 	do {
-		mutex_lock(&gt->i915->drm.struct_mutex);
-
 		for_each_engine(engine, gt->i915, id) {
 			int i;
 
@@ -417,7 +414,6 @@ static int igt_reset_nop(void *arg)
 		intel_gt_reset(gt, ALL_ENGINES, NULL);
 		igt_global_reset_unlock(gt);
 
-		mutex_unlock(&gt->i915->drm.struct_mutex);
 		if (intel_gt_is_wedged(gt)) {
 			err = -EIO;
 			break;
@@ -429,16 +425,13 @@ static int igt_reset_nop(void *arg)
 			break;
 		}
 
-		err = igt_flush_test(gt->i915, 0);
+		err = igt_flush_test(gt->i915);
 		if (err)
 			break;
 	} while (time_before(jiffies, end_time));
 	pr_info("%s: %d resets\n", __func__, count);
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
-	err = igt_flush_test(gt->i915, I915_WAIT_LOCKED);
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
+	err = igt_flush_test(gt->i915);
 out:
 	mock_file_free(gt->i915, file);
 	if (intel_gt_is_wedged(gt))
@@ -494,7 +487,6 @@ static int igt_reset_nop_engine(void *arg)
 				break;
 			}
 
-			mutex_lock(&gt->i915->drm.struct_mutex);
 			for (i = 0; i < 16; i++) {
 				struct i915_request *rq;
 
@@ -507,7 +499,6 @@ static int igt_reset_nop_engine(void *arg)
 				i915_request_add(rq);
 			}
 			err = intel_engine_reset(engine, NULL);
-			mutex_unlock(&gt->i915->drm.struct_mutex);
 			if (err) {
 				pr_err("i915_reset_engine failed\n");
 				break;
@@ -533,15 +524,12 @@ static int igt_reset_nop_engine(void *arg)
 		if (err)
 			break;
 
-		err = igt_flush_test(gt->i915, 0);
+		err = igt_flush_test(gt->i915);
 		if (err)
 			break;
 	}
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
-	err = igt_flush_test(gt->i915, I915_WAIT_LOCKED);
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
+	err = igt_flush_test(gt->i915);
 out:
 	mock_file_free(gt->i915, file);
 	if (intel_gt_is_wedged(gt))
@@ -563,9 +551,7 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 		return 0;
 
 	if (active) {
-		mutex_lock(&gt->i915->drm.struct_mutex);
 		err = hang_init(&h, gt);
-		mutex_unlock(&gt->i915->drm.struct_mutex);
 		if (err)
 			return err;
 	}
@@ -593,17 +579,14 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 			if (active) {
 				struct i915_request *rq;
 
-				mutex_lock(&gt->i915->drm.struct_mutex);
 				rq = hang_create_request(&h, engine);
 				if (IS_ERR(rq)) {
 					err = PTR_ERR(rq);
-					mutex_unlock(&gt->i915->drm.struct_mutex);
 					break;
 				}
 
 				i915_request_get(rq);
 				i915_request_add(rq);
-				mutex_unlock(&gt->i915->drm.struct_mutex);
 
 				if (!wait_until_running(&h, rq)) {
 					struct drm_printer p = drm_info_printer(gt->i915->drm.dev);
@@ -647,7 +630,7 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 		if (err)
 			break;
 
-		err = igt_flush_test(gt->i915, 0);
+		err = igt_flush_test(gt->i915);
 		if (err)
 			break;
 	}
@@ -655,11 +638,8 @@ static int __igt_reset_engine(struct intel_gt *gt, bool active)
 	if (intel_gt_is_wedged(gt))
 		err = -EIO;
 
-	if (active) {
-		mutex_lock(&gt->i915->drm.struct_mutex);
+	if (active)
 		hang_fini(&h);
-		mutex_unlock(&gt->i915->drm.struct_mutex);
-	}
 
 	return err;
 }
@@ -741,10 +721,8 @@ static int active_engine(void *data)
 		struct i915_request *old = rq[idx];
 		struct i915_request *new;
 
-		mutex_lock(&engine->i915->drm.struct_mutex);
 		new = igt_request_alloc(ctx[idx], engine);
 		if (IS_ERR(new)) {
-			mutex_unlock(&engine->i915->drm.struct_mutex);
 			err = PTR_ERR(new);
 			break;
 		}
@@ -755,7 +733,6 @@ static int active_engine(void *data)
 
 		rq[idx] = i915_request_get(new);
 		i915_request_add(new);
-		mutex_unlock(&engine->i915->drm.struct_mutex);
 
 		err = active_request_put(old);
 		if (err)
@@ -795,9 +772,7 @@ static int __igt_reset_engines(struct intel_gt *gt,
 		return 0;
 
 	if (flags & TEST_ACTIVE) {
-		mutex_lock(&gt->i915->drm.struct_mutex);
 		err = hang_init(&h, gt);
-		mutex_unlock(&gt->i915->drm.struct_mutex);
 		if (err)
 			return err;
 
@@ -855,17 +830,14 @@ static int __igt_reset_engines(struct intel_gt *gt,
 			struct i915_request *rq = NULL;
 
 			if (flags & TEST_ACTIVE) {
-				mutex_lock(&gt->i915->drm.struct_mutex);
 				rq = hang_create_request(&h, engine);
 				if (IS_ERR(rq)) {
 					err = PTR_ERR(rq);
-					mutex_unlock(&gt->i915->drm.struct_mutex);
 					break;
 				}
 
 				i915_request_get(rq);
 				i915_request_add(rq);
-				mutex_unlock(&gt->i915->drm.struct_mutex);
 
 				if (!wait_until_running(&h, rq)) {
 					struct drm_printer p = drm_info_printer(gt->i915->drm.dev);
@@ -977,9 +949,7 @@ unwind:
 		if (err)
 			break;
 
-		mutex_lock(&gt->i915->drm.struct_mutex);
-		err = igt_flush_test(gt->i915, I915_WAIT_LOCKED);
-		mutex_unlock(&gt->i915->drm.struct_mutex);
+		err = igt_flush_test(gt->i915);
 		if (err)
 			break;
 	}
@@ -987,11 +957,8 @@ unwind:
 	if (intel_gt_is_wedged(gt))
 		err = -EIO;
 
-	if (flags & TEST_ACTIVE) {
-		mutex_lock(&gt->i915->drm.struct_mutex);
+	if (flags & TEST_ACTIVE)
 		hang_fini(&h);
-		mutex_unlock(&gt->i915->drm.struct_mutex);
-	}
 
 	return err;
 }
@@ -1061,7 +1028,6 @@ static int igt_reset_wait(void *arg)
 
 	igt_global_reset_lock(gt);
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
 	err = hang_init(&h, gt);
 	if (err)
 		goto unlock;
@@ -1109,7 +1075,6 @@ out_rq:
 fini:
 	hang_fini(&h);
 unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
 	igt_global_reset_unlock(gt);
 
 	if (intel_gt_is_wedged(gt))
@@ -1189,10 +1154,9 @@ static int __igt_reset_evict_vma(struct intel_gt *gt,
 
 	/* Check that we can recover an unbind stuck on a hanging request */
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
 	err = hang_init(&h, gt);
 	if (err)
-		goto unlock;
+		return err;
 
 	obj = i915_gem_object_create_internal(gt->i915, SZ_1M);
 	if (IS_ERR(obj)) {
@@ -1255,8 +1219,6 @@ static int __igt_reset_evict_vma(struct intel_gt *gt,
 	if (err)
 		goto out_rq;
 
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
 	if (!wait_until_running(&h, rq)) {
 		struct drm_printer p = drm_info_printer(gt->i915->drm.dev);
 
@@ -1305,16 +1267,12 @@ out_reset:
 		put_task_struct(tsk);
 	}
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
 out_rq:
 	i915_request_put(rq);
 out_obj:
 	i915_gem_object_put(obj);
 fini:
 	hang_fini(&h);
-unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
 	if (intel_gt_is_wedged(gt))
 		return -EIO;
 
@@ -1396,7 +1354,6 @@ static int igt_reset_queue(void *arg)
 
 	igt_global_reset_lock(gt);
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
 	err = hang_init(&h, gt);
 	if (err)
 		goto unlock;
@@ -1511,7 +1468,7 @@ static int igt_reset_queue(void *arg)
 
 		i915_request_put(prev);
 
-		err = igt_flush_test(gt->i915, I915_WAIT_LOCKED);
+		err = igt_flush_test(gt->i915);
 		if (err)
 			break;
 	}
@@ -1519,7 +1476,6 @@ static int igt_reset_queue(void *arg)
 fini:
 	hang_fini(&h);
 unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
 	igt_global_reset_unlock(gt);
 
 	if (intel_gt_is_wedged(gt))
@@ -1546,11 +1502,9 @@ static int igt_handle_error(void *arg)
 	if (!engine || !intel_engine_can_store_dword(engine))
 		return 0;
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
-
 	err = hang_init(&h, gt);
 	if (err)
-		goto err_unlock;
+		return err;
 
 	rq = hang_create_request(&h, engine);
 	if (IS_ERR(rq)) {
@@ -1574,8 +1528,6 @@ static int igt_handle_error(void *arg)
 		goto err_request;
 	}
 
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
 	/* Temporarily disable error capture */
 	error = xchg(&global->first_error, (void *)-1);
 
@@ -1583,8 +1535,6 @@ static int igt_handle_error(void *arg)
 
 	xchg(&global->first_error, error);
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
-
 	if (rq->fence.error != -EIO) {
 		pr_err("Guilty request not identified!\n");
 		err = -EINVAL;
@@ -1595,8 +1545,6 @@ err_request:
 	i915_request_put(rq);
 err_fini:
 	hang_fini(&h);
-err_unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
 	return err;
 }
 
@@ -1689,7 +1637,6 @@ static int igt_reset_engines_atomic(void *arg)
 		return 0;
 
 	igt_global_reset_lock(gt);
-	mutex_lock(&gt->i915->drm.struct_mutex);
 
 	/* Flush any requests before we get started and check basics */
 	if (!igt_force_reset(gt))
@@ -1709,9 +1656,7 @@ static int igt_reset_engines_atomic(void *arg)
 out:
 	/* As we poke around the guts, do a full reset before continuing. */
 	igt_force_reset(gt);
-
 unlock:
-	mutex_unlock(&gt->i915->drm.struct_mutex);
 	igt_global_reset_unlock(gt);
 
 	return err;
@@ -1751,10 +1696,6 @@ int intel_hangcheck_live_selftests(struct drm_i915_private *i915)
 
 	err = intel_gt_live_subtests(tests, gt);
 
-	mutex_lock(&gt->i915->drm.struct_mutex);
-	igt_flush_test(gt->i915, I915_WAIT_LOCKED);
-	mutex_unlock(&gt->i915->drm.struct_mutex);
-
 	i915_modparams.enable_hangcheck = saved_hangcheck;
 	intel_runtime_pm_put(&gt->i915->runtime_pm, wakeref);