Re: [PATCH v2 3/3] mm: add WQ_PERCPU to alloc_workqueue users

[Frederic Weisbecker <frederic@kernel.org>]

Le Sat, Jan 24, 2026 at 03:22:41PM -0800, Andrew Morton a écrit :
> On Sat, 24 Jan 2026 23:21:35 +0100 Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> 
> > On 2026-01-13 12:46:30 [+0100], Marco Crivellari wrote:
> > > --- a/mm/slub.c
> > > +++ b/mm/slub.c
> > > @@ -8542,7 +8542,9 @@ void __init kmem_cache_init(void)
> > >  
> > >  void __init kmem_cache_init_late(void)
> > >  {
> > > -	flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM, 0);
> > > +#ifndef CONFIG_SLUB_TINY
> > 
> > This ifndef does not belong here.
> > 
> > > +	flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM | WQ_PERCPU,
> > > +				  0);
> > >  	WARN_ON(!flushwq);
> > >  }
> 
> Yup, thanks, mm.git is carrying a -fix patch, which is actually wrong.
> 
> 
> From: Andrew Morton <akpm@linux-foundation.org>
> Subject: mm-add-wq_percpu-to-alloc_workqueue-users-fix
> Date: Tue Jan 13 05:59:13 PM PST 2026
> 
> fix mm/slub.c
> 
> Cc: Marco Crivellari <marco.crivellari@suse.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
> 
>  mm/slub.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> --- a/mm/slub.c~mm-add-wq_percpu-to-alloc_workqueue-users-fix
> +++ a/mm/slub.c
> @@ -8546,6 +8546,7 @@ void __init kmem_cache_init_late(void)
>  	flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM | WQ_PERCPU,
>  				  0);
>  	WARN_ON(!flushwq);
> +#endif
>  }
>  
>  struct kmem_cache *
> 
> 
> 
> I'll add this:
> 
> --- a/mm/slub.c~mm-add-wq_percpu-to-alloc_workqueue-users-fix-fix
> +++ a/mm/slub.c
> @@ -8542,11 +8542,9 @@ void __init kmem_cache_init(void)
>  
>  void __init kmem_cache_init_late(void)
>  {
> -#ifndef CONFIG_SLUB_TINY
>  	flushwq = alloc_workqueue("slub_flushwq", WQ_MEM_RECLAIM | WQ_PERCPU,
>  				  0);
>  	WARN_ON(!flushwq);
> -#endif

With that as a fixup, looks good:

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>

-- 
Frederic Weisbecker
SUSE Labs