---

yaml
---
r: 275255
b: refs/heads/master
c: 7a1619b
h: refs/heads/master
i:
  275253: a7252d7
  275251: 9a332e2
  275247: 4514f04
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 471dd2ef3761de01348b19e83128a778df1d45b2
+refs/heads/master: 7a1619b97e978bb9c05fa4bbe64171068bd5bf85

trunk/drivers/gpu/drm/radeon/radeon.h

@@ -1142,6 +1142,48 @@ struct r600_vram_scratch {
 	u64				gpu_addr;
 };
 
+
+/*
+ * Mutex which allows recursive locking from the same process.
+ */
+struct radeon_mutex {
+	struct mutex		mutex;
+	struct task_struct	*owner;
+	int			level;
+};
+
+static inline void radeon_mutex_init(struct radeon_mutex *mutex)
+{
+	mutex_init(&mutex->mutex);
+	mutex->owner = NULL;
+	mutex->level = 0;
+}
+
+static inline void radeon_mutex_lock(struct radeon_mutex *mutex)
+{
+	if (mutex_trylock(&mutex->mutex)) {
+		/* The mutex was unlocked before, so it's ours now */
+		mutex->owner = current;
+	} else if (mutex->owner != current) {
+		/* Another process locked the mutex, take it */
+		mutex_lock(&mutex->mutex);
+		mutex->owner = current;
+	}
+	/* Otherwise the mutex was already locked by this process */
+
+	mutex->level++;
+}
+
+static inline void radeon_mutex_unlock(struct radeon_mutex *mutex)
+{
+	if (--mutex->level > 0)
+		return;
+
+	mutex->owner = NULL;
+	mutex_unlock(&mutex->mutex);
+}
+
+
 /*
  * Core structure, functions and helpers.
  */
@@ -1197,7 +1239,7 @@ struct radeon_device {
 	struct radeon_gem		gem;
 	struct radeon_pm		pm;
 	uint32_t			bios_scratch[RADEON_BIOS_NUM_SCRATCH];
-	struct mutex			cs_mutex;
+	struct radeon_mutex		cs_mutex;
 	struct radeon_wb		wb;
 	struct radeon_dummy_page	dummy_page;
 	bool				gpu_lockup;

trunk/drivers/gpu/drm/radeon/radeon_cs.c

@@ -222,7 +222,7 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	struct radeon_cs_chunk *ib_chunk;
 	int r;
 
-	mutex_lock(&rdev->cs_mutex);
+	radeon_mutex_lock(&rdev->cs_mutex);
 	/* initialize parser */
 	memset(&parser, 0, sizeof(struct radeon_cs_parser));
 	parser.filp = filp;
@@ -233,22 +233,22 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	if (r) {
 		DRM_ERROR("Failed to initialize parser !\n");
 		radeon_cs_parser_fini(&parser, r);
-		mutex_unlock(&rdev->cs_mutex);
+		radeon_mutex_unlock(&rdev->cs_mutex);
 		return r;
 	}
 	r =  radeon_ib_get(rdev, &parser.ib);
 	if (r) {
 		DRM_ERROR("Failed to get ib !\n");
 		radeon_cs_parser_fini(&parser, r);
-		mutex_unlock(&rdev->cs_mutex);
+		radeon_mutex_unlock(&rdev->cs_mutex);
 		return r;
 	}
 	r = radeon_cs_parser_relocs(&parser);
 	if (r) {
 		if (r != -ERESTARTSYS)
 			DRM_ERROR("Failed to parse relocation %d!\n", r);
 		radeon_cs_parser_fini(&parser, r);
-		mutex_unlock(&rdev->cs_mutex);
+		radeon_mutex_unlock(&rdev->cs_mutex);
 		return r;
 	}
 	/* Copy the packet into the IB, the parser will read from the
@@ -260,22 +260,22 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	if (r || parser.parser_error) {
 		DRM_ERROR("Invalid command stream !\n");
 		radeon_cs_parser_fini(&parser, r);
-		mutex_unlock(&rdev->cs_mutex);
+		radeon_mutex_unlock(&rdev->cs_mutex);
 		return r;
 	}
 	r = radeon_cs_finish_pages(&parser);
 	if (r) {
 		DRM_ERROR("Invalid command stream !\n");
 		radeon_cs_parser_fini(&parser, r);
-		mutex_unlock(&rdev->cs_mutex);
+		radeon_mutex_unlock(&rdev->cs_mutex);
 		return r;
 	}
 	r = radeon_ib_schedule(rdev, parser.ib);
 	if (r) {
 		DRM_ERROR("Failed to schedule IB !\n");
 	}
 	radeon_cs_parser_fini(&parser, r);
-	mutex_unlock(&rdev->cs_mutex);
+	radeon_mutex_unlock(&rdev->cs_mutex);
 	return r;
 }
 

trunk/drivers/gpu/drm/radeon/radeon_device.c

@@ -716,7 +716,7 @@ int radeon_device_init(struct radeon_device *rdev,
 
 	/* mutex initialization are all done here so we
 	 * can recall function without having locking issues */
-	mutex_init(&rdev->cs_mutex);
+	radeon_mutex_init(&rdev->cs_mutex);
 	mutex_init(&rdev->ib_pool.mutex);
 	mutex_init(&rdev->cp.mutex);
 	mutex_init(&rdev->dc_hw_i2c_mutex);
@@ -955,6 +955,9 @@ int radeon_gpu_reset(struct radeon_device *rdev)
 	int r;
 	int resched;
 
+	/* Prevent CS ioctl from interfering */
+	radeon_mutex_lock(&rdev->cs_mutex);
+
 	radeon_save_bios_scratch_regs(rdev);
 	/* block TTM */
 	resched = ttm_bo_lock_delayed_workqueue(&rdev->mman.bdev);
@@ -967,10 +970,15 @@ int radeon_gpu_reset(struct radeon_device *rdev)
 		radeon_restore_bios_scratch_regs(rdev);
 		drm_helper_resume_force_mode(rdev->ddev);
 		ttm_bo_unlock_delayed_workqueue(&rdev->mman.bdev, resched);
-		return 0;
 	}
-	/* bad news, how to tell it to userspace ? */
-	dev_info(rdev->dev, "GPU reset failed\n");
+
+	radeon_mutex_unlock(&rdev->cs_mutex);
+
+	if (r) {
+		/* bad news, how to tell it to userspace ? */
+		dev_info(rdev->dev, "GPU reset failed\n");
+	}
+
 	return r;
 }