Messages in this thread | | | From | James Houghton <> | Date | Tue, 21 Feb 2023 08:16:41 -0800 | Subject | Re: [PATCH v2 08/46] hugetlb: add HugeTLB HGM enablement helpers |
| |
On Fri, Feb 17, 2023 at 5:40 PM Mina Almasry <almasrymina@google.com> wrote: > > On Fri, Feb 17, 2023 at 4:28 PM James Houghton <jthoughton@google.com> wrote: > > > > hugetlb_hgm_eligible indicates that a VMA is eligible to have HGM > > explicitly enabled via MADV_SPLIT, and hugetlb_hgm_enabled indicates > > that HGM has been enabled. > > > > Signed-off-by: James Houghton <jthoughton@google.com> > > Only nits: > Reviewed-by: Mina Almasry <almasrymina@google.com>
Thanks Mina. :)
> > > > > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > > index 7c977d234aba..efd2635a87f5 100644 > > --- a/include/linux/hugetlb.h > > +++ b/include/linux/hugetlb.h > > @@ -1211,6 +1211,20 @@ static inline void hugetlb_unregister_node(struct node *node) > > } > > #endif /* CONFIG_HUGETLB_PAGE */ > > > > +#ifdef CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING > > +bool hugetlb_hgm_enabled(struct vm_area_struct *vma); > > +bool hugetlb_hgm_eligible(struct vm_area_struct *vma); > > +#else > > +static inline bool hugetlb_hgm_enabled(struct vm_area_struct *vma) > > +{ > > + return false; > > +} > > +static inline bool hugetlb_hgm_eligible(struct vm_area_struct *vma) > > +{ > > + return false; > > +} > > +#endif > > + > > static inline spinlock_t *huge_pte_lock(struct hstate *h, > > struct mm_struct *mm, pte_t *pte) > > { > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > > index 6c008c9de80e..0576dcc98044 100644 > > --- a/mm/hugetlb.c > > +++ b/mm/hugetlb.c > > @@ -7004,6 +7004,10 @@ static bool pmd_sharing_possible(struct vm_area_struct *vma) > > #ifdef CONFIG_USERFAULTFD > > if (uffd_disable_huge_pmd_share(vma)) > > return false; > > +#endif > > +#ifdef CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING > > + if (hugetlb_hgm_enabled(vma)) > > + return false; > > #endif > > /* > > * Only shared VMAs can share PMDs. > > @@ -7267,6 +7271,18 @@ __weak unsigned long hugetlb_mask_last_page(struct hstate *h) > > > > #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ > > > > +#ifdef CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING > > +bool hugetlb_hgm_eligible(struct vm_area_struct *vma) > > I think the other function you named pmd_sharing_possible(), I suggest > hugetlb_hgm_possible() for some consistency.
Good idea. Will do.
> > > +{ > > + /* All shared VMAs may have HGM. */ > > I think this is a redundant comment.
Indeed. I'll change it to something like:
"HGM is not supported for private mappings. Operations that apply to MAP_PRIVATE VMAs like hugetlb_wp haven't been updated to support high-granularity mappings."
> > > + return vma && (vma->vm_flags & VM_MAYSHARE); > > +} > > +bool hugetlb_hgm_enabled(struct vm_area_struct *vma) > > +{ > > + return vma && (vma->vm_flags & VM_HUGETLB_HGM); > > +} > > +#endif /* CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING */ > > + > > /* > > * These functions are overwritable if your architecture needs its own > > * behavior. > > -- > > 2.39.2.637.g21b0678d19-goog > >
| |