Quoting Christian König (2019-08-06 16:01:31)
Other cores don't busy wait any more and we removed the last user of checking the seqno for changes. Drop updating the number for shared fences altogether.
Signed-off-by: Christian König christian.koenig@amd.com
drivers/dma-buf/reservation.c | 6 ------ drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 7 +------ 2 files changed, 1 insertion(+), 12 deletions(-)
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index c0ba05936ab6..944d962ddddf 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -237,9 +237,6 @@ void reservation_object_add_shared_fence(struct reservation_object *obj, fobj = reservation_object_get_list(obj); count = fobj->shared_count;
preempt_disable();write_seqcount_begin(&obj->seq);for (i = 0; i < count; ++i) { old = rcu_dereference_protected(fobj->shared[i],@@ -257,9 +254,6 @@ void reservation_object_add_shared_fence(struct reservation_object *obj, RCU_INIT_POINTER(fobj->shared[i], fence); /* pointer update must be visible before we extend the shared_count */ smp_store_mb(fobj->shared_count, count);
Yup, that's all the mb rules we need to apply for the rcu readers to see a consistent view.
Reviewed-by: Chris Wilson chris@chris-wilson.co.uk -Chris