X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fgpu%2Fdrm%2Fttm%2Fttm_page_alloc_dma.c;h=de1a753b1d563549a652987872a01d995c1782e3;hb=05b29f94a4ab4f37071025b0c235516c2616bce6;hp=b8b394319b45947facd37036817b73ac39a2661c;hpb=cf9ce948f47640797bd19980e1d99c6d17d0bdc3;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
index b8b394319b45..de1a753b1d56 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
@@ -1006,9 +1006,9 @@ EXPORT_SYMBOL_GPL(ttm_dma_unpopulate);
 static int ttm_dma_pool_mm_shrink(struct shrinker *shrink,
 				  struct shrink_control *sc)
 {
-	static atomic_t start_pool = ATOMIC_INIT(0);
+	static unsigned start_pool;
 	unsigned idx = 0;
-	unsigned pool_offset = atomic_add_return(1, &start_pool);
+	unsigned pool_offset;
 	unsigned shrink_pages = sc->nr_to_scan;
 	struct device_pools *p;
 
@@ -1016,7 +1016,9 @@ static int ttm_dma_pool_mm_shrink(struct shrinker *shrink,
 		return 0;
 
 	mutex_lock(&_manager->lock);
-	pool_offset = pool_offset % _manager->npools;
+	if (!_manager->npools)
+		goto out;
+	pool_offset = ++start_pool % _manager->npools;
 	list_for_each_entry(p, &_manager->pools, pools) {
 		unsigned nr_free;
 
@@ -1033,6 +1035,7 @@ static int ttm_dma_pool_mm_shrink(struct shrinker *shrink,
 			 p->pool->dev_name, p->pool->name, current->pid,
 			 nr_free, shrink_pages);
 	}
+out:
 	mutex_unlock(&_manager->lock);
 	/* return estimated number of unused pages in pool */
 	return ttm_dma_pool_get_num_unused_pages();