This cures my x220 as well. OK bcook@
On Jul 26, 2014 6:56 AM, "Mark Kettenis" <mark.kette...@xs4all.nl> wrote:
> Thanks to the evil Intel AMT serial, I've been able to figure out what
> made my x220 hang when suspending. Turns out that the fix matthew@
> committed almost two weeks ago uncovered another bug that made
> sched_stop_secondary_cpus() spin forever if there was a processing
> running on a secondary cpu but nothing left on the run qeueue. In
> that case sched_choosecpu() short-circuits and returns the current
> cpu. The fix is obvious: don't short-circuit when we're on a cpu that
> should stop.
>
> ok?
>
>
> Index: kern_sched.c
> ===================================================================
> RCS file: /home/cvs/src/sys/kern/kern_sched.c,v
> retrieving revision 1.33
> diff -u -p -r1.33 kern_sched.c
> --- kern_sched.c 13 Jul 2014 21:44:58 -0000 1.33
> +++ kern_sched.c 26 Jul 2014 11:44:26 -0000
> @@ -275,6 +275,7 @@ sched_chooseproc(void)
> while ((p =
> TAILQ_FIRST(&spc->spc_qs[queue]))) {
> remrunqueue(p);
> p->p_cpu = sched_choosecpu(p);
> + KASSERT(p->p_cpu != curcpu());
> setrunqueue(p);
> }
> }
> @@ -408,6 +409,7 @@ sched_choosecpu(struct proc *p)
> */
> if (cpuset_isset(&set, p->p_cpu) ||
> (p->p_cpu == curcpu() && p->p_cpu->ci_schedstate.spc_nrun == 0
> &&
> + (p->p_cpu->ci_schedstate.spc_schedflags & SPCF_SHOULDHALT) ==
> 0 &&
> curproc == p)) {
> sched_wasidle++;
> return (p->p_cpu);
>
>
