Re: futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op
From: Thomas Gleixner
Date: Wed Jul 06 2016 - 15:00:16 EST
On Thu, 23 Jun 2016, Michael Kerrisk (man-pages) wrote:
> On 06/23/2016 08:28 PM, Darren Hart wrote:
> > And as a follow-on, what is the reason for FUTEX_LOCK_PI only using
> > CLOCK_REALTIME? It seems reasonable to me that a user may want to wait a
> > specific amount of time, regardless of wall time.
>
> Yes, that's another weird inconsistency.
The reason is that phtread_mutex_timedlock() uses absolute timeouts based on
CLOCK_REALTIME. glibc folks asked to make that the default behaviour back then
when we added LOCK_PI.
Thanks,
tglx