svn commit: r303563 - head/sys/kern

[Conrad Meyer]

On Sat, Jul 30, 2016 at 3:23 PM, Mateusz Guzik <mjg at freebsd.org> wrote:
> Author: mjg
> Date: Sat Jul 30 22:23:31 2016
> New Revision: 303563
> URL: https://svnweb.freebsd.org/changeset/base/303563
>
> Log:
>   sx: increment spin_cnt before cpu_spinwait in xlock

Looks like it's after cpu_spinwait instead.

>
>   The change is a no-op only done for consistency with the rest of the file.
>
> Modified:
>   head/sys/kern/kern_sx.c
>
> Modified: head/sys/kern/kern_sx.c
> ==============================================================================
> --- head/sys/kern/kern_sx.c     Sat Jul 30 22:21:48 2016        (r303562)
> +++ head/sys/kern/kern_sx.c     Sat Jul 30 22:23:31 2016        (r303563)
> @@ -889,10 +889,10 @@ _sx_slock_hard(struct sx *sx, int opts,
>                                 GIANT_SAVE();
>                                 while (SX_OWNER(sx->sx_lock) == x &&
>                                     TD_IS_RUNNING(owner)) {
> +                                       cpu_spinwait();
>  #ifdef KDTRACE_HOOKS
>                                         spin_cnt++;
>  #endif
> -                                       cpu_spinwait();
>                                 }
>                                 KTR_STATE0(KTR_SCHED, "thread",
>                                     sched_tdname(curthread), "running");
>