Re: [PATCH V2 0/6][RFC] futex: FUTEX_LOCK with optional adaptivespinning

[Alan Cox]

> That works for the uncontended case.  For the contended case, the waiter 
> and the owner have to go into the kernel and back out to transfer 
> ownership.

If you insist on doing it that way yes, but knowing the lock owner is
likely to be away for a while also lets you do things like punt work
either by picking another work package in the meantime, or by queueing
the work you can't do on a list the pre-empted lock owner will review
before dropping the lock.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/