drm/xe: Add xe_exec_queue_last_fence_test_dep

Helpful to determine if a bind can immediately use CPU or needs to be
deferred a drm scheduler job.

v7:
 - Better wording in kernel doc (Matthew Auld)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240704041652.272920-4-matthew.brost@intel.com

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
index 0ba37835849b016975b0796937154040d76fde34..3336a01a1006536b7c082bfe119ca67c94ceef41 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.c
+++ b/drivers/gpu/drm/xe/xe_exec_queue.c
@@ -906,3 +906,26 @@ void xe_exec_queue_last_fence_set(struct xe_exec_queue *q, struct xe_vm *vm,
        xe_exec_queue_last_fence_put(q, vm);
        q->last_fence = dma_fence_get(fence);
 }
+
+/**
+ * xe_exec_queue_last_fence_test_dep - Test last fence dependency of queue
+ * @q: The exec queue
+ * @vm: The VM the engine does a bind or exec for
+ *
+ * Returns:
+ * -ETIME if there exists an unsignalled last fence dependency, zero otherwise.
+ */
+int xe_exec_queue_last_fence_test_dep(struct xe_exec_queue *q, struct xe_vm *vm)
+{
+       struct dma_fence *fence;
+       int err = 0;
+
+       fence = xe_exec_queue_last_fence_get(q, vm);
+       if (fence) {
+               err = test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags) ?
+                       0 : -ETIME;
+               dma_fence_put(fence);
+       }
+
+       return err;
+}

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.h b/drivers/gpu/drm/xe/xe_exec_queue.h
index 289a3a51d2a21b1f5c55094ca941851d1d14e358..ded77b0f3b9066f9dc2a87011fd465e08e71a384 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.h
+++ b/drivers/gpu/drm/xe/xe_exec_queue.h
@@ -75,6 +75,8 @@ struct dma_fence *xe_exec_queue_last_fence_get(struct xe_exec_queue *e,
                                               struct xe_vm *vm);
 void xe_exec_queue_last_fence_set(struct xe_exec_queue *e, struct xe_vm *vm,
                                  struct dma_fence *fence);
+int xe_exec_queue_last_fence_test_dep(struct xe_exec_queue *q,
+                                     struct xe_vm *vm);
 void xe_exec_queue_update_run_ticks(struct xe_exec_queue *q);
 
 #endif