ion: free low memory from page pools first

When the shrinkers are called with GFP_HIGH free low memory first,
it is more important to have free than high memory.

Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ion/ion_page_pool.c

@@ -143,10 +143,10 @@ int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
 		struct page *page;
 
 		mutex_lock(&pool->mutex);
-		if (high && pool->high_count) {
-			page = ion_page_pool_remove(pool, true);
-		} else if (pool->low_count) {
+		if (pool->low_count) {
 			page = ion_page_pool_remove(pool, false);
+		} else if (high && pool->high_count) {
+			page = ion_page_pool_remove(pool, true);
 		} else {
 			mutex_unlock(&pool->mutex);
 			break;