diff options
| -rw-r--r-- | drivers/android/binder/node.rs | 20 | ||||
| -rw-r--r-- | drivers/android/binder/node/wrapper.rs | 34 |
2 files changed, 50 insertions, 4 deletions
diff --git a/drivers/android/binder/node.rs b/drivers/android/binder/node.rs index 0a82af14c..8dc3e3f2b 100644 --- a/drivers/android/binder/node.rs +++ b/drivers/android/binder/node.rs @@ -51,9 +51,9 @@ pub(crate) struct CouldNotDeliverCriticalIncrement; /// about to drop the weak reference, then the strong increment could be processed after the /// other thread has already exited, which would be too late. /// -/// Note that trying to create a `ListArc` to the node can succeed even if `has_normal_push` is +/// Note that trying to create a `ListArc` to the node can succeed even if `has_pushed_node` is /// set. This is because another thread might just have popped the node from a todo list, but not -/// yet called `do_work`. However, if `has_normal_push` is false, then creating a `ListArc` should +/// yet called `do_work`. However, if `has_pushed_node` is false, then creating a `ListArc` should /// always succeed. /// /// Like the other fields in `NodeInner`, the delivery state is protected by the process lock. @@ -738,7 +738,21 @@ impl DeliverToRead for Node { self.do_work_locked(writer, owner_inner) } - fn cancel(self: DArc<Self>) {} + fn cancel(self: DArc<Self>) { + let _drop_outside_lock; + let mut owner_inner = self.owner.inner.lock(); + + // We only do something on BINDER_THREAD_EXIT, not process exit. + if owner_inner.is_dead { + return; + } + + // If BINDER_THREAD_EXIT is invoked on a thread with a pending node refcount update, we + // should move ourselves to ensure the refcount update is still delivered. + if let Some(node) = ListArc::try_from_arc_borrow(self.as_arc_borrow()) { + _drop_outside_lock = owner_inner.push_work(&self.owner, node); + } + } fn should_sync_wakeup(&self) -> bool { false diff --git a/drivers/android/binder/node/wrapper.rs b/drivers/android/binder/node/wrapper.rs index 6e4ca01c9..886626ca0 100644 --- a/drivers/android/binder/node/wrapper.rs +++ b/drivers/android/binder/node/wrapper.rs @@ -57,7 +57,39 @@ impl DeliverToRead for NodeWrapper { node.do_work_locked(writer, owner_inner) } - fn cancel(self: DArc<Self>) {} + fn cancel(self: DArc<Self>) { + let _drop_outside_lock; + let node = &self.node; + let mut owner_inner = node.owner.inner.lock(); + + // We only do something on BINDER_THREAD_EXIT, not process exit. + if owner_inner.is_dead { + return; + } + + // We transfer the responsibility of the node refcount update to the scheduled Node because + // NodeWrapper has no way to re-create the ListArc. + let inner = node.inner.access_mut(&mut owner_inner); + + let ds = &mut inner.delivery_state; + assert!(ds.has_pushed_wrapper); + assert!(ds.has_strong_zero2one); + ds.has_pushed_wrapper = false; + + // We are changing the state to one where the Node is the strong zero2one update instead of + // the wrapper. + ds.has_weak_zero2one = false; + + if !ds.has_pushed_node { + if let Some(node2) = ListArc::try_from_arc_borrow(node.as_arc_borrow()) { + ds.has_pushed_node = true; + _drop_outside_lock = owner_inner.push_work(&node.owner, node2); + } else { + // This can't actually happen. + ds.has_strong_zero2one = false; + } + } + } fn should_sync_wakeup(&self) -> bool { false |
