Re: [RFC][PATCH 2/4] mm, slub: implement slub allocate post callback for page_owner

From: jeff . xie
Date: Thu Nov 09 2023 - 10:34:34 EST


November 9, 2023 at 10:05 PM, "Matthew Wilcox" <willy@xxxxxxxxxxxxx> wrote:


>
> On Thu, Nov 09, 2023 at 11:25:19AM +0800, Jeff Xie wrote:
>
> >
> > +#ifdef CONFIG_PAGE_OWNER
> > +static int slab_alloc_post_page_owner(struct folio *folio, struct task_struct *tsk,
> > + void *data, char *kbuf, size_t count)
> > +{
> > + int ret;
> > + struct kmem_cache *kmem_cache = data;
> > +
> > + ret = scnprintf(kbuf, count, "SLAB_PAGE slab_name:%s\n", kmem_cache->name);
> > +
> > + return ret;
> > +}
> > +#endif
> >
>
> Or we could do this typesafely ...
>
> struct slab *slab = folio_slab(folio);
> struct kmem_cache *kmem_cache = slab->slab_cache;
>
> ... and then there's no need to pass in a 'data' to the function.
>

I accidentally replied using my other email (xiehuan09@xxxxxxxxx) just now.
Thank you for your advice. Indeed, the "data" didn't serve any purpose here.

--
Jeff Xie