| Message ID | 1520319653-4743-1-git-send-email-Monk.Liu@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
And still a NAK, the prerequisite for adding a shared fence is that it is later than any existing fence in that context. In other words reservation_object_add_shared_fence() is always called with a new fence, never with some old one. So the whole checking here is completely superfluous, Christian. Am 06.03.2018 um 08:00 schrieb Monk Liu: > v2: > still check context first to avoid warning from dma_fence_is_later > apply this fix in add_shared_replace as well > > v3: > use a bool falg to indict if fence is need to insert to new slot > and ignore it if it is an eld fence compared with the one with > the same context in old->shared > > Change-Id: If6a979ba9fd6c923b82212f35f07a9ff31c86767 > Signed-off-by: Monk Liu <Monk.Liu@amd.com> > --- > drivers/dma-buf/reservation.c | 28 ++++++++++++++++++++++------ > 1 file changed, 22 insertions(+), 6 deletions(-) > > diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c > index 314eb10..a7d0598 100644 > --- a/drivers/dma-buf/reservation.c > +++ b/drivers/dma-buf/reservation.c > @@ -118,7 +118,8 @@ reservation_object_add_shared_inplace(struct reservation_object *obj, > old_fence = rcu_dereference_protected(fobj->shared[i], > reservation_object_held(obj)); > > - if (old_fence->context == fence->context) { > + if (old_fence->context == fence->context && > + dma_fence_is_later(fence, old_fence)) { > /* memory barrier is added by write_seqcount_begin */ > RCU_INIT_POINTER(fobj->shared[i], fence); > write_seqcount_end(&obj->seq); > @@ -158,6 +159,7 @@ reservation_object_add_shared_replace(struct reservation_object *obj, > struct dma_fence *fence) > { > unsigned i, j, k; > + bool wrong_fence = false; > > dma_fence_get(fence); > > @@ -179,15 +181,29 @@ reservation_object_add_shared_replace(struct reservation_object *obj, > check = rcu_dereference_protected(old->shared[i], > reservation_object_held(obj)); > > - if (check->context == fence->context || > - dma_fence_is_signaled(check)) > + if (dma_fence_is_signaled(check)) { > + /* put check to tail of fobj if signaled */ > RCU_INIT_POINTER(fobj->shared[--k], check); > - else > + } else if (check->context == fence->context) { > + if (dma_fence_is_later(fence, check)) { > + /* put check to tail of fobj if it is deprecated */ > + RCU_INIT_POINTER(fobj->shared[--k], check); > + } else { > + /* this is a wrong operation that add an eld fence */ > + wrong_fence = true; > + RCU_INIT_POINTER(fobj->shared[j++], check); > + } > + } else { > + /* add fence to new slot */ > RCU_INIT_POINTER(fobj->shared[j++], check); > + } > } > + > fobj->shared_count = j; > - RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); > - fobj->shared_count++; > + if (!wrong_fence) { > + RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); > + fobj->shared_count++; > + } > > done: > preempt_disable();
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 314eb10..a7d0598 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -118,7 +118,8 @@ reservation_object_add_shared_inplace(struct reservation_object *obj, old_fence = rcu_dereference_protected(fobj->shared[i], reservation_object_held(obj)); - if (old_fence->context == fence->context) { + if (old_fence->context == fence->context && + dma_fence_is_later(fence, old_fence)) { /* memory barrier is added by write_seqcount_begin */ RCU_INIT_POINTER(fobj->shared[i], fence); write_seqcount_end(&obj->seq); @@ -158,6 +159,7 @@ reservation_object_add_shared_replace(struct reservation_object *obj, struct dma_fence *fence) { unsigned i, j, k; + bool wrong_fence = false; dma_fence_get(fence); @@ -179,15 +181,29 @@ reservation_object_add_shared_replace(struct reservation_object *obj, check = rcu_dereference_protected(old->shared[i], reservation_object_held(obj)); - if (check->context == fence->context || - dma_fence_is_signaled(check)) + if (dma_fence_is_signaled(check)) { + /* put check to tail of fobj if signaled */ RCU_INIT_POINTER(fobj->shared[--k], check); - else + } else if (check->context == fence->context) { + if (dma_fence_is_later(fence, check)) { + /* put check to tail of fobj if it is deprecated */ + RCU_INIT_POINTER(fobj->shared[--k], check); + } else { + /* this is a wrong operation that add an eld fence */ + wrong_fence = true; + RCU_INIT_POINTER(fobj->shared[j++], check); + } + } else { + /* add fence to new slot */ RCU_INIT_POINTER(fobj->shared[j++], check); + } } + fobj->shared_count = j; - RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); - fobj->shared_count++; + if (!wrong_fence) { + RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); + fobj->shared_count++; + } done: preempt_disable();
v2: still check context first to avoid warning from dma_fence_is_later apply this fix in add_shared_replace as well v3: use a bool falg to indict if fence is need to insert to new slot and ignore it if it is an eld fence compared with the one with the same context in old->shared Change-Id: If6a979ba9fd6c923b82212f35f07a9ff31c86767 Signed-off-by: Monk Liu <Monk.Liu@amd.com> --- drivers/dma-buf/reservation.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-)