@@ -407,14 +407,21 @@ void dma_fence_enable_sw_signaling(struct dma_fence *fence);
* is signaled yet.
* @fence: the fence to check
*
- * Returns true if the fence was already signaled, false if not. Since this
- * function doesn't enable signaling, it is not guaranteed to ever return
- * true if dma_fence_add_callback(), dma_fence_wait() or
+ * Checks whether the fence was already signaled, and, if not, whether
+ * &struct dma_fence_ops.signaled indicates that it should be signaled. If so,
+ * the fence gets signaled here.
+ *
+ * Since this function doesn't enable signaling, it is not guaranteed to ever
+ * return true if dma_fence_add_callback(), dma_fence_wait() or
* dma_fence_enable_sw_signaling() haven't been called before.
*
* This function requires &dma_fence.lock to be held.
*
* See also dma_fence_is_signaled().
+ *
+ * Return: true if the fence was already signaled, or if
+ * &struct dma_fence_ops.signaled is implemented and indicates that this fence
+ * can be treated as signaled; false otherwise.
*/
static inline bool
dma_fence_is_signaled_locked(struct dma_fence *fence)
@@ -434,9 +441,12 @@ dma_fence_is_signaled_locked(struct dma_fence *fence)
* dma_fence_is_signaled - Return an indication if the fence is signaled yet.
* @fence: the fence to check
*
- * Returns true if the fence was already signaled, false if not. Since this
- * function doesn't enable signaling, it is not guaranteed to ever return
- * true if dma_fence_add_callback(), dma_fence_wait() or
+ * Checks whether the fence was already signaled, and, if not, whether
+ * &struct dma_fence_ops.signaled indicates that it should be signaled. If so,
+ * the fence gets signaled here.
+ *
+ * Since this function doesn't enable signaling, it is not guaranteed to ever
+ * return true if dma_fence_add_callback(), dma_fence_wait() or
* dma_fence_enable_sw_signaling() haven't been called before.
*
* It's recommended for seqno fences to call dma_fence_signal when the
@@ -445,6 +455,10 @@ dma_fence_is_signaled_locked(struct dma_fence *fence)
* value of this function before calling hardware-specific wait instructions.
*
* See also dma_fence_is_signaled_locked().
+ *
+ * Return: true if the fence was already signaled, or if
+ * &struct dma_fence_ops.signaled is implemented and indicates that this fence
+ * can be treated as signaled; false otherwise.
*/
static inline bool
dma_fence_is_signaled(struct dma_fence *fence)
The current documentation of dma_fence_is_signaled() and dma_fence_is_signaled_locked() does not explicitly mention that those functions can signal the fence. Furthermore, the documentation of the return value reads as if the returned boolean only describes whether dma_fence_signal() (or similar) had been called before this function call already. That's not the case, since dma_fence_ops.signaled() usually just checks through the sequence number whether the hardware is finished with a fence. That doesn't mean a signaling function has been called already. Make the documentation clearer. Move the Return: documentation to the end, since that's the officially recommended docu style. Signed-off-by: Philipp Stanner <phasta@kernel.org> --- include/linux/dma-fence.h | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-)