On Thu, 7 May 2015 12:53:27 +0530 "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> wrote: > After this patch pmdp_* functions operate only on hugepage pte, > and not on regular pmd_t values pointing to page table. > The patch looks like a pretty safe no-op for non-powerpc? > --- a/arch/powerpc/include/asm/pgtable-ppc64.h > +++ b/arch/powerpc/include/asm/pgtable-ppc64.h > @@ -576,6 +576,10 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr, > extern void pmdp_splitting_flush(struct vm_area_struct *vma, > unsigned long address, pmd_t *pmdp); > > +#define __HAVE_ARCH_PMDP_COLLAPSE_FLUSH > +extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, > + unsigned long address, pmd_t *pmdp); > + The fashionable way of doing this is extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp); #define pmdp_collapse_flush pmdp_collapse_flush then, elsewhere, #ifndef pmdp_collapse_flush static inline pmd_t pmdp_collapse_flush(...) {} #define pmdp_collapse_flush pmdp_collapse_flush #endif It avoids introducing a second (ugly) symbol into the kernel. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>