Re: [PATCH v2 4/7] mm: extend the template fast path to zone-device compound tails

["Li Zhe" <lizhe.67@bytedance.com>]

On Sat, 23 May 2026 15:10:52 +0300, rppt@kernel.org wrote:

> On Thu, 21 May 2026 12:01:21 +0800, Li Zhe <lizhe.67@bytedance.com> wrote:
> > diff --git a/mm/mm_init.c b/mm/mm_init.c
> > index 2992711351a0..17a84d4cda01 100644
> > --- a/mm/mm_init.c
> > +++ b/mm/mm_init.c
> > @@ -1084,17 +1084,25 @@ static inline bool zone_device_page_init_optimization_enabled(void)
> >  		IS_ALIGNED(sizeof(struct page), sizeof(u64));
> >  }
> >
> > -static inline void zone_device_template_page_init(struct page *template,
> > -						  unsigned long pfn,
> > -						  unsigned long zone_idx,
> > -						  int nid,
> > -						  struct dev_pagemap *pgmap)
> > +static inline void zone_device_template_head_page_init(struct page *template,
> > +		unsigned long pfn, unsigned long zone_idx, int nid,
> > +		struct dev_pagemap *pgmap)
> 
> Yeah, two tabs from the start would be better :)
> 
> > @@ -1156,12 +1166,28 @@ static void __ref memmap_init_compound(struct page *head,
> > [ ... skip 17 lines ... ]
> > -		zone_device_page_init_slow(page, pfn, zone_idx, nid, pgmap);
> > -		prep_compound_tail(page, head, order);
> > -		set_page_count(page, 0);
> > +		if (use_template) {
> > +			zone_device_page_init_from_template(page, pfn,
> > +							    &template);
> 
> continue here and there won't be need to indent the slow path.
> 
> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

Thanks for the review. I will fix this in the next revision.

Thanks,
Zhe