Messages in this thread Patch in this message | | | From | Naoya Horiguchi <> | Subject | [PATCH -mm v2 01/11] pagewalk: remove pgd_entry() and pud_entry() | Date | Thu, 12 Jun 2014 17:48:01 -0400 |
| |
Currently no user of page table walker sets ->pgd_entry() or ->pud_entry(), so checking their existence in each loop is just wasting CPU cycle. So let's remove it to reduce overhead.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> --- include/linux/mm.h | 6 ------ mm/pagewalk.c | 18 +----------------- 2 files changed, 1 insertion(+), 23 deletions(-)
diff --git mmotm-2014-05-21-16-57.orig/include/linux/mm.h mmotm-2014-05-21-16-57/include/linux/mm.h index 563c79ea07bd..b4aa6579f2b1 100644 --- mmotm-2014-05-21-16-57.orig/include/linux/mm.h +++ mmotm-2014-05-21-16-57/include/linux/mm.h @@ -1092,8 +1092,6 @@ void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma, /** * mm_walk - callbacks for walk_page_range - * @pgd_entry: if set, called for each non-empty PGD (top-level) entry - * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry * this handler is required to be able to handle * pmd_trans_huge() pmds. They may simply choose to @@ -1115,10 +1113,6 @@ void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma, * (see the comment on walk_page_range() for more details) */ struct mm_walk { - int (*pgd_entry)(pgd_t *pgd, unsigned long addr, - unsigned long next, struct mm_walk *walk); - int (*pud_entry)(pud_t *pud, unsigned long addr, - unsigned long next, struct mm_walk *walk); int (*pmd_entry)(pmd_t *pmd, unsigned long addr, unsigned long next, struct mm_walk *walk); int (*pte_entry)(pte_t *pte, unsigned long addr, diff --git mmotm-2014-05-21-16-57.orig/mm/pagewalk.c mmotm-2014-05-21-16-57/mm/pagewalk.c index 2eda3dbe0b52..e734f63276c2 100644 --- mmotm-2014-05-21-16-57.orig/mm/pagewalk.c +++ mmotm-2014-05-21-16-57/mm/pagewalk.c @@ -115,14 +115,6 @@ static int walk_pud_range(pgd_t *pgd, unsigned long addr, continue; } - if (walk->pud_entry) { - err = walk->pud_entry(pud, addr, next, walk); - if (skip_lower_level_walking(walk)) - continue; - if (err) - break; - } - if (walk->pmd_entry || walk->pte_entry) { err = walk_pmd_range(pud, addr, next, walk); if (err) @@ -152,15 +144,7 @@ static int walk_pgd_range(unsigned long addr, unsigned long end, continue; } - if (walk->pgd_entry) { - err = walk->pgd_entry(pgd, addr, next, walk); - if (skip_lower_level_walking(walk)) - continue; - if (err) - break; - } - - if (walk->pud_entry || walk->pmd_entry || walk->pte_entry) { + if (walk->pmd_entry || walk->pte_entry) { err = walk_pud_range(pgd, addr, next, walk); if (err) break; -- 1.9.3
| |