[PATCH 20/25] drm/exynos: drop struct_mutex from exynos_gem_map_sgt_with_dma

Daniel Vetter daniel.vetter at ffwll.ch
Thu Oct 15 00:36:36 PDT 2015


The sg table isn't refcounted, there's no corresponding locking for
unmapping and drm_map_sg is ok with being called concurrently.

So drop the locking since it doesn't protect anything.

Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
 drivers/gpu/drm/exynos/exynos_drm_gem.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index f6c7bc3a7e68..cf34c7f9ed93 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -367,16 +367,12 @@ int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
 {
 	int nents;
 
-	mutex_lock(&drm_dev->struct_mutex);
-
 	nents = dma_map_sg(drm_dev->dev, sgt->sgl, sgt->nents, dir);
 	if (!nents) {
 		DRM_ERROR("failed to map sgl with dma.\n");
-		mutex_unlock(&drm_dev->struct_mutex);
 		return nents;
 	}
 
-	mutex_unlock(&drm_dev->struct_mutex);
 	return 0;
 }
 
-- 
2.5.1



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