On Tue, 2007-03-13 at 10:52 +0100, [EMAIL PROTECTED] wrote:
> plain text document attachment (futex-requeue-pi.diff)
> This patch provides the futex_requeue_pi functionality.
> 
> This provides an optimization, already used for (normal) futexes, to be used 
> for
> PI-futexes.
> 
> This optimization is currently used by the glibc in pthread_broadcast, when
> using "normal" mutexes. With futex_requeue_pi, it can be used with 
> PRIO_INHERIT
> mutexes too.
> 
> Signed-off-by: Pierre Peiffer <[EMAIL PROTECTED]>
> 
> ---

>  /*
> + * Retrieve the original address used to compute this key
> + */
> +static void *get_futex_address(union futex_key *key)
> +{
> +     void *uaddr;
> +
> +     if (key->both.offset & 1) {
> +             /* shared mapping */
> +             uaddr = (void*)((key->shared.pgoff << PAGE_SHIFT)
> +                             + key->shared.offset - 1);
> +     } else {
> +             /* private mapping */
> +             uaddr = (void*)(key->private.address + key->private.offset);
> +     }
> +
> +     return uaddr;
> +}

This will not work for nonlinear vmas, granted, not a lot of ppl stick
futexes in nonlinear vmas, but the futex_key stuff handles it, this
doesn't.


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

Reply via email to