From: Rob Clark <robdclark@xxxxxxxxxxxx> Any cross-device sync use-cases *must* use explicit sync. And if there is only a single ring (no-preemption), everything is FIFO order and there is no need to implicit-sync. Mesa should probably just always use MSM_SUBMIT_NO_IMPLICIT, as behavior is undefined when fences are not used to synchronize buffer usage across contexts (which is the only case where multiple different priority rings could come into play). Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> --- drivers/gpu/drm/msm/msm_gem_submit.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c index 7d653bdc92dc..b9b68153b7b2 100644 --- a/drivers/gpu/drm/msm/msm_gem_submit.c +++ b/drivers/gpu/drm/msm/msm_gem_submit.c @@ -219,7 +219,7 @@ static int submit_lock_objects(struct msm_gem_submit *submit) return ret; } -static int submit_fence_sync(struct msm_gem_submit *submit, bool no_implicit) +static int submit_fence_sync(struct msm_gem_submit *submit, bool implicit_sync) { int i, ret = 0; @@ -239,7 +239,7 @@ static int submit_fence_sync(struct msm_gem_submit *submit, bool no_implicit) return ret; } - if (no_implicit) + if (!implicit_sync) continue; ret = msm_gem_sync_object(&msm_obj->base, submit->ring->fctx, @@ -704,7 +704,8 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data, if (ret) goto out; - ret = submit_fence_sync(submit, !!(args->flags & MSM_SUBMIT_NO_IMPLICIT)); + ret = submit_fence_sync(submit, (gpu->nr_rings > 1) && + !(args->flags & MSM_SUBMIT_NO_IMPLICIT)); if (ret) goto out; -- 2.26.2 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel