Why there's a SendWrapper in compio-runtime::runtime::RunnableQueue

[SaltyKitkat]

The field local_runnables is wrapped in a SendWrapper, which makes RunnableQueue be Send + Sync.
But it seems that RunnableQueue is only referenced in Runtime, which is not Send nor Sync?
So why do we need this sendwrapper?

ps: I tried to make the sendwrapper !Send + !Sync, but compio seems compiles with no error.

[SaltyKitkat]

Ok, I think I got it.
RunnableQueue must be Send + Sync for schedule, while async_task doesn't provide an api with not 'static future and Send + Sync schedule.

[Berrysoft]

Well, yes, it's mainly for validity. The schedule closure will check if the current thread is the same thread as the runtime, so the RefCell won't be accessed in other threads.

[SaltyKitkat]

Got it!
Thank you.