Document the optional condition semantics of WAIT_EVENT. When condition fields are provided, WAIT_EVENT completes only when both: - a matching event record exists, and - the userspace condition passes
Matching records are consumed only on successful completion. Cc: Alex Deucher <[email protected]> Cc: Christian König <[email protected]> Signed-off-by: Srinivasan Shanmugam <[email protected]> --- drivers/gpu/drm/amd/amdgpu/amdgpu_wait_event.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_wait_event.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_wait_event.h index 67de685647c7..3cccc652360f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_wait_event.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_wait_event.h @@ -45,6 +45,16 @@ struct amdgpu_wait_event_mgr { bool dead; }; +/* + * WAIT_EVENT semantics: + * + * - WAIT_EVENT matches pending records by event type and optional queue id. + * - If cond_op is DRM_AMDGPU_WAIT_COND_NONE, a matching record completes + * the wait immediately. + * - If cond_op is set, WAIT_EVENT completes only when both the record + * match and the userspace memory condition pass. + * - Matching records are consumed only on successful completion. + */ void amdgpu_wait_event_mgr_init(struct amdgpu_wait_event_mgr *mgr); void amdgpu_wait_event_mgr_fini(struct amdgpu_wait_event_mgr *mgr); -- 2.34.1
