SurfaceFlinger: Use a lockless stack for binder->tracing thread

Though the critical section is kept very small between the binder
and tracing threads, the tracing thread is not RT, and so we still
run the risk of it being descheduled and blocking one of our binder
threads excessively. In this thread we provide a simple lockless
stack implementation and use it to push pending transactions from
the binder thread to the main thread. We also looked up "layer IDs"
on the binder thread, which is no longer possible without the lock.
To work around this we store the pointer itself in the proto until
it reaches the tracing thread where we overwrite it with the mapped
value.

Bug: 200284593
Test: Existing tests pass
Change-Id: I408dc87ddfe088b68f65601455147a96b870627d

0 files changed, 0 insertions, 0 deletions