Fence signaling must be enabled to make sure that the dma_fence_is_signaled() function ever returns true. Since drivers and implementations sometimes mess this up, this ensures correct behaviour when DEBUG_WW_MUTEX_SLOWPATH is used during debugging. This should make any implementation bugs resulting in not signaled fences much more obvious.
Signed-off-by: Arvind Yadav Arvind.Yadav@amd.com ---
Changes in v1,v2 : 1- Addressing Christian's comment to replace CONFIG_DEBUG_WW_MUTEX_SLOWPATH instead of CONFIG_DEBUG_FS. 2- As per Christian's comment moving this patch at last so The version of this patch is also changed and previously it was [PATCH 1/4]
--- include/linux/dma-fence.h | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index 775cdc0b4f24..ba1ddc14c5d4 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -428,6 +428,11 @@ dma_fence_is_signaled_locked(struct dma_fence *fence) static inline bool dma_fence_is_signaled(struct dma_fence *fence) { +#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH + if (!test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags)) + return false; +#endif + if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) return true;