Removes the need for a write lock each time we call ttm_bo_unref().
v2: Remove an unused variable.
Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo.c | 4 +---
drivers/gpu/drm/ttm/ttm_bo_vm.c | 4 ++--
2 files changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 7426fe5..2dd0238 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -696,6 +696,7 @@ static void ttm_bo_release(struct kref *kref)
struct ttm_bo_device *bdev = bo->bdev;
struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
+ write_lock(&bdev->vm_lock);
if (likely(bo->vm_node != NULL)) {
rb_erase(&bo->vm_rb, &bdev->addr_space_rb);
drm_mm_put_block(bo->vm_node);
@@ -707,7 +708,6 @@ static void ttm_bo_release(struct kref *kref)
ttm_mem_io_unlock(man);
ttm_bo_cleanup_refs_or_queue(bo);
kref_put(&bo->list_kref, ttm_bo_release_list);
- write_lock(&bdev->vm_lock);
}
void ttm_bo_unref(struct ttm_buffer_object **p_bo)
@@ -716,9 +716,7 @@ void ttm_bo_unref(struct ttm_buffer_object **p_bo)
struct ttm_bo_device *bdev = bo->bdev;
*p_bo = NULL;
- write_lock(&bdev->vm_lock);
kref_put(&bo->kref, ttm_bo_release);
- write_unlock(&bdev->vm_lock);
}
EXPORT_SYMBOL(ttm_bo_unref);
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 3ba72db..74705f3 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -259,8 +259,8 @@ int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
read_lock(&bdev->vm_lock);
bo = ttm_bo_vm_lookup_rb(bdev, vma->vm_pgoff,
(vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
- if (likely(bo != NULL))
- ttm_bo_reference(bo);
+ if (likely(bo != NULL) && !kref_get_unless_zero(&bo->kref))
+ bo = NULL;
read_unlock(&bdev->vm_lock);
if (unlikely(bo == NULL)) {
--
1.7.4.4
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/dri-devel
