Hi,
Today, there are several functionalities or improvements about futexes included
in -rt kernel tree, which, I think, it make sense to have in mainline.
Among them, there are:
* futex use prio list : allows RT-threads to be woken in priority order
instead of FIFO order.
* futex_wait use hrtimer : allows the use of finer timer resolution.
* futex_requeue_pi functionality : allows use of requeue optimization for
PI-mutexes/PI-futexes.
* futex64 syscall : allows use of 64-bit futexes instead of 32-bit.
The following mails provide the corresponding patches.
I re-send this series for kernel 2.6.20-rc5 with this small modifications:
- futex_use_prio_list patch stores now all non-real-time threads with the same
priority (MAX_RT_PRIO, which is a lower priority than real-time priorities),
causing them to be stored in FIFO order. RT-threads are still woken first in
priority order.
- futex_requeue_pi: I've found (and corrected of course) a bug causing a
memory leak.
plist (patch 1/4) is still under discussion: I think it should be taken into
account, because it concerns a correctness issue with a very low cost as
drawback (I would even say "without noticeable cost" ;-) but that's my opinion
of course).
Anyway, I still can provide the same series without patch 1/4 if needed.
Comments and feedback are still welcome, as usual.
--
Pierre