Seems that during refactorings of child cancellations we somehow missed
also cancelling the group itself. It seems we did not have good test
coverage of the addTaskUnlessCancelled somehow and thus this slipped
through.
This adds a regression test for addTaskUnlessCancelled and fixes how we
handle the cancellation effect in TaskStatus.
resolves#80789
resolves rdar://149177600
We were detaching the child by just modifying the list, but the cancellation path was assuming that that would not be done without holding the task status lock.
This patch just fixes the current runtime; the back-deployment side is complicated.
Fixes rdar://88398824
handler of parent task that created the group
Change comment in TaskGroup.swift to enforce that only parent task can
call cancelAll on the group
Add tests to verify mutating of task group in child tasks will fail
Radar-Id: rdar://problem/86346865
when a task is adding adding new children to a task group, we need to
synchronize with the task status record lock of the parent task that has the
task group, to prevent races with concurrent cancellation and escalation.
Radar-Id: rdar://problem/86311782
Most of the async runtime functions have been changed to not
expect the task and executor to be passed in. When knowing the
task and executor is necessary, there are runtime functions
available to recover them.
The biggest change I had to make to a runtime function signature
was to swift_task_switch, which has been altered to expect to be
passed the context and resumption function instead of requiring
the caller to park the task. This has the pleasant consequence
of allowing the implementation to very quickly turn around when
it recognizes that the current executor is satisfactory. It does
mean that on arm64e we have to sign the continuation function
pointer as an argument and then potentially resign it when
assigning into the task's resume slot.
rdar://70546948
