Messages in this thread | | | From | Geert Uytterhoeven <> | Date | Fri, 17 Jun 2022 17:26:31 +0200 | Subject | Re: [PATCH 1/4] hugetlb: skip to end of PT page mapping when pte not present |
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Hi Peter,
On Fri, Jun 17, 2022 at 4:22 PM Peter Xu <peterx@redhat.com> wrote: > On Thu, Jun 16, 2022 at 02:05:15PM -0700, Mike Kravetz wrote: > > @@ -6877,6 +6896,39 @@ pte_t *huge_pte_offset(struct mm_struct *mm, > > return (pte_t *)pmd; > > } > > > > +/* > > + * Return a mask that can be used to update an address to the last huge > > + * page in a page table page mapping size. Used to skip non-present > > + * page table entries when linearly scanning address ranges. Architectures > > + * with unique huge page to page table relationships can define their own > > + * version of this routine. > > + */ > > +unsigned long hugetlb_mask_last_page(struct hstate *h) > > +{ > > + unsigned long hp_size = huge_page_size(h); > > + > > + switch (hp_size) { > > + case P4D_SIZE: > > + return PGDIR_SIZE - P4D_SIZE; > > + case PUD_SIZE: > > + return P4D_SIZE - PUD_SIZE; > > + case PMD_SIZE: > > + return PUD_SIZE - PMD_SIZE; > > + default: > > Should we add a WARN_ON_ONCE() if it should never trigger?
And with panic_on_warn, it'll panic only once ;-)
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
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