Re: [GIT PULL] workqueue fixes for v4.13-rc3

Geert Uytterhoeven
2017-08-23T08:10:58Z

Hi Tejun,

On Mon, Aug 7, 2017 at 7:06 PM, Tejun Heo <tj@kernel.org> wrote:
> On Mon, Aug 07, 2017 at 02:18:51PM +0200, Geert Uytterhoeven wrote:
>> This triggers on m68k, which doesn't have SMP.
>> Haven't tried it yet on any other system due to holidays.
>
> That's weird. Can you please apply the following patch and report the
> messages?
>
> Thanks.
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index ca937b0..1b9d21b 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -3579,8 +3579,10 @@ static bool wq_calc_node_cpumask(const struct workqueue_attrs *attrs, int node,
> cpumask_and(cpumask, attrs->cpumask, wq_numa_possible_cpumask[node]);
>
> if (cpumask_empty(cpumask)) {
> - pr_warn_once("WARNING: workqueue cpumask: online intersect > "
> - "possible intersect\n");
> + pr_warn_once("WARNING: workqueue empty cpumask: node=%d cpu_going_down=%d cpumask=%*pb online=%*pb possible=%*pb\n",
> + node, cpu_going_down, cpumask_pr_args(attrs->cpumask),
> + cpumask_pr_args(cpumask_of_node(node)),
> + cpumask_pr_args(wq_numa_possible_cpumask[node]));

WARNING: workqueue empty cpumask: node=1 cpu_going_down=-1 cpumask=1
online=1 possible=0

> return false;
> }
>
> @@ -5526,6 +5528,9 @@ static void __init wq_numa_init(void)
>
> wq_numa_possible_cpumask = tbl;
> wq_numa_enabled = true;
> +
> + for_each_node(node)
> + printk("XXX wq node[%d] %*pb\n", node, cpumask_pr_args(wq_numa_possible_cpumask[node]));

XXX wq node[0] 1
XXX wq node[1] 0
XXX wq node[2] 0
XXX wq node[3] 0
XXX wq node[4] 0
XXX wq node[5] 0
XXX wq node[6] 0
XXX wq node[7] 0

> }

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds