[LTP] [patch V2 00/20] timer: Refactor the timer wheel

Thomas Gleixner
2016-06-23T15:21:14Z

On Thu, 23 Jun 2016, Cyril Hrubis wrote:
> > 1) sigtimedwait() is unusual in that it uses the jiffies timer. Most
> > system call timeouts (including specifically the one in FUTEX_WAIT)
> > use the high-resolution timer subsystem, which is a whole different
> > animal with tighter guarantees, and
>
> That is likely POSIX conformance bug, since POSIX explicitly states that
> sigtimedwait() shall use CLOCK_MONOTONIC to measure the timeout.
>
> "If the Monotonic Clock option is supported, the CLOCK_MONOTONIC clock
> shall be used to measure the time interval specified by the timeout
> argument."

That's fine because jiffies is a less granular form of CLOCK_MONOTONIC.

Thanks,

tglx