Messages in this thread Patch in this message | | | From | "Aneesh Kumar K.V" <> | Subject | Re: [RFC PATCH 1/3] mm/thp: Use pmdp_splitting_flush_notify to clear pmd on splitting | Date | Thu, 30 Apr 2015 22:17:04 +0530 |
| |
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> writes:
> "Kirill A. Shutemov" <kirill@shutemov.name> writes: > >>> @@ -184,3 +185,13 @@ void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, >>> } >>> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ >>> #endif >>> + >>> +#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH_NOTIFY >>> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE >>> +void pmdp_splitting_flush_notify(struct vm_area_struct *vma, >>> + unsigned long address, pmd_t *pmdp) >>> +{ >>> + pmdp_clear_flush_notify(vma, address, pmdp); >>> +} >>> +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ >>> +#endif >> >> I think it worth inlining. Let's put it to <asm-generic/pgtable.h> >> >> It probably worth combining with collapse counterpart in the same patch. >> > > I tried that first, But that pulls in mmu_notifier.h and huge_mm.h > headers and other build failures >
Putting them in TRANSPATENT_HUGEPAGE helped.
commit 9c60ab5d1d684db2ba454ee1c7f3e9a6bf57f026 Author: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Date: Wed Apr 29 14:57:30 2015 +0530
mm/thp: Use pmdp_splitting_flush_notify to clear pmd on splitting
Some arch may require an explicit IPI before a THP PMD split. This ensures that a local_irq_disable can prevent a parallel THP PMD split. So use new function which arch can override
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index fe617b7e4be6..6a0b2ab899d1 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -184,6 +184,24 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif +#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH_NOTIFY +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline void pmdp_splitting_flush_notify(struct vm_area_struct *vma, + unsigned long address, + pmd_t *pmdp) +{ + pmdp_clear_flush_notify(vma, address, pmdp); +} +#else +static inline void pmdp_splitting_flush_notify(struct vm_area_struct *vma, + unsigned long address, + pmd_t *pmdp) +{ + BUG(); +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif + #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, pgtable_t pgtable); diff --git a/mm/huge_memory.c b/mm/huge_memory.c index cce4604c192f..81e9578bf43a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2606,9 +2606,10 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, write = pmd_write(*pmd); young = pmd_young(*pmd); - - /* leave pmd empty until pte is filled */ - pmdp_clear_flush_notify(vma, haddr, pmd); + /* + * leave pmd empty until pte is filled. + */ + pmdp_splitting_flush_notify(vma, haddr, pmd); pgtable = pgtable_trans_huge_withdraw(mm, pmd); pmd_populate(mm, &_pmd, pgtable);
| |