Since drm_mm_node are intended to be embedded into larger structs, we can use the DEBUG_OBJECTS facility to help track the lifetime of the drm_mm_node and ensure that they are not being used after the containing object has been freed, along with the usual verification that the drm_mm_nodes are being used correctly.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk --- drivers/gpu/drm/Kconfig | 13 +++++++ drivers/gpu/drm/drm_mm.c | 54 ++++++++++++++++++++++++++++ drivers/gpu/drm/i915/gt/gen6_ppgtt.c | 2 -- drivers/gpu/drm/i915/i915_vma.c | 17 +++++++-- include/drm/drm_mm.h | 19 ++++++++++ 5 files changed, 100 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 43594978958e..33ac38be55b0 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -54,6 +54,19 @@ config DRM_DEBUG_MM
If in doubt, say "N".
+config DRM_DEBUG_MM_OBJECTS + bool "Use debugobjects to track live drm_mm_nodes" + default n + depends on DRM_DEBUG_MM + depends on DEBUG_OBJECTS + help + Enable allocation tracking of memory manager and leak detection on + shutdown. + + Recommended for driver developers only. + + If in doubt, say "N". + config DRM_DEBUG_SELFTEST tristate "kselftests for DRM" depends on DRM diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index bc6e208949e8..c149c54d8ede 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -150,6 +150,41 @@ static void save_stack(struct drm_mm_node *node) { } static void show_leaks(struct drm_mm *mm) { } #endif
+#ifdef CONFIG_DRM_DEBUG_MM_OBJECTS + +static struct debug_obj_descr drm_mm_debug_descr = { + .name = "drm_mm_node", +}; + +static inline void debug_node_init(struct drm_mm_node *node) +{ + debug_object_init(node, &drm_mm_debug_descr); +} + +static inline void debug_node_activate(struct drm_mm_node *node) +{ + debug_object_activate(node, &drm_mm_debug_descr); +} + +static inline void debug_node_deactivate(struct drm_mm_node *node) +{ + debug_object_deactivate(node, &drm_mm_debug_descr); +} + +static inline void debug_node_free(struct drm_mm_node *node) +{ + debug_object_free(node, &drm_mm_debug_descr); +} + +#else + +static inline void debug_node_init(struct drm_mm_node *node) { } +static inline void debug_node_activate(struct drm_mm_node *node) { } +static inline void debug_node_deactivate(struct drm_mm_node *node) { } +static inline void debug_node_free(struct drm_mm_node *node) { } + +#endif + #define START(node) ((node)->start) #define LAST(node) ((node)->start + (node)->size - 1)
@@ -428,6 +463,8 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node) if (adj_start > node->start || adj_end < end) return -ENOSPC;
+ debug_node_activate(node); + node->mm = mm;
__set_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags); @@ -543,6 +580,8 @@ int drm_mm_insert_node_in_range(struct drm_mm * const mm, } }
+ debug_node_activate(node); + node->mm = mm; node->size = size; node->start = adj_start; @@ -587,6 +626,7 @@ void drm_mm_remove_node(struct drm_mm_node *node)
DRM_MM_BUG_ON(!drm_mm_node_allocated(node)); DRM_MM_BUG_ON(drm_mm_node_scanned_block(node)); + debug_node_deactivate(node);
prev_node = list_prev_entry(node, node_list);
@@ -618,6 +658,8 @@ void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new) struct drm_mm *mm = old->mm;
DRM_MM_BUG_ON(!drm_mm_node_allocated(old)); + debug_node_deactivate(old); + debug_node_activate(new);
*new = *old;
@@ -639,6 +681,18 @@ void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new) } EXPORT_SYMBOL(drm_mm_replace_node);
+void __drm_mm_node_init(struct drm_mm_node *node) +{ + debug_node_init(node); +} +EXPORT_SYMBOL(__drm_mm_node_init); + +void __drm_mm_node_fini(struct drm_mm_node *node) +{ + debug_node_free(node); +} +EXPORT_SYMBOL(__drm_mm_node_fini); + /** * DOC: lru scan roster * diff --git a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c index f4fec7eb4064..0c34d4dd6458 100644 --- a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c +++ b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c @@ -359,8 +359,6 @@ static struct i915_vma *pd_vma_create(struct gen6_ppgtt *ppgtt, int size)
i915_active_init(&vma->active, NULL, NULL);
- kref_init(&vma->ref); - mutex_init(&vma->pages_mutex); vma->vm = i915_vm_get(&ggtt->vm); vma->ops = &pd_vma_ops; vma->private = ppgtt; diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 5b3efb43a8ef..64140d51ae2c 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -45,11 +45,24 @@ static struct i915_global_vma {
struct i915_vma *i915_vma_alloc(void) { - return kmem_cache_zalloc(global.slab_vmas, GFP_KERNEL); + struct i915_vma *vma; + + vma = kmem_cache_zalloc(global.slab_vmas, GFP_KERNEL); + if (!vma) + return NULL; + + kref_init(&vma->ref); + mutex_init(&vma->pages_mutex); + drm_mm_node_init(&vma->node); + + return vma; }
void i915_vma_free(struct i915_vma *vma) { + drm_mm_node_fini(&vma->node); + mutex_destroy(&vma->pages_mutex); + return kmem_cache_free(global.slab_vmas, vma); }
@@ -114,8 +127,6 @@ vma_create(struct drm_i915_gem_object *obj, if (vma == NULL) return ERR_PTR(-ENOMEM);
- kref_init(&vma->ref); - mutex_init(&vma->pages_mutex); vma->vm = i915_vm_get(vm); vma->ops = &vm->vma_ops; vma->obj = obj; diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index d7939c054259..5ecadb7ca8fb 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -275,6 +275,25 @@ static inline bool drm_mm_initialized(const struct drm_mm *mm) return mm->hole_stack.next; }
+#ifdef CONFIG_DRM_DEBUG_MM_OBJECTS +void __drm_mm_node_init(struct drm_mm_node *node); +void __drm_mm_node_fini(struct drm_mm_node *node); +#else +static inline void __drm_mm_node_init(struct drm_mm_node *node) { } +static inline void __drm_mm_node_fini(struct drm_mm_node *node) { } +#endif + +static inline void drm_mm_node_init(struct drm_mm_node *node) +{ + __drm_mm_node_init(node); + memset(node, 0, sizeof(*node)); +} + +static inline void drm_mm_node_fini(struct drm_mm_node *node) +{ + __drm_mm_node_fini(node); +} + /** * drm_mm_hole_follows - checks whether a hole follows this node * @node: drm_mm_node to check