[Patch v2] drm/ttm: Use init_on_free to delay release TTM BOs

[Rajneesh Bhardwaj]

Delay release TTM BOs when the kernel default setting is init_on_free.
This offloads the overhead of clearing the system memory to the work
item and potentially a different CPU. This could be very beneficial when
the application does a lot of malloc/free style allocations of system
memory.

Reviewed-by: Christian König <christian.koenig at amd.com>.
Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj at amd.com>
---
Changes in v2:
- Updated commit message as per Christian's feedback

 drivers/gpu/drm/ttm/ttm_bo.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 326a3d13a829..bd2e7e4f497a 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -347,6 +347,7 @@ static void ttm_bo_release(struct kref *kref)
 
 		if (!dma_resv_test_signaled(bo->base.resv,
 					    DMA_RESV_USAGE_BOOKKEEP) ||
+		    (want_init_on_free() && (bo->ttm != NULL)) ||
 		    !dma_resv_trylock(bo->base.resv)) {
 			/* The BO is not idle, resurrect it for delayed destroy */
 			ttm_bo_flush_all_fences(bo);
-- 
2.17.1