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mm/memory.c: remove reduntant check for write access 

Flags argument has been copied into vmf.flags and it is not changed in
between.  Hence a single write access check can be used for both PUD and
PMD.

Link: http://lkml.kernel.org/r/20170823082839.1812-1-khandual@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Anshuman Khandual 2017-09-08 16:12:45 -07:00 committed by Linus Torvalds
parent 656710a60e
commit fde26bed58
1 changed files with 2 additions and 3 deletions
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5
mm/memory.c
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@ -3961,6 +3961,7 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
.pgoff = linear_page_index(vma, address), .pgoff = linear_page_index(vma, address),
.gfp_mask = __get_fault_gfp_mask(vma), .gfp_mask = __get_fault_gfp_mask(vma),
}; };
unsigned int dirty = flags & FAULT_FLAG_WRITE;
struct mm_struct *mm = vma->vm_mm; struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd; pgd_t *pgd;
p4d_t *p4d; p4d_t *p4d;
@ -3983,7 +3984,6 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
barrier(); barrier();
if (pud_trans_huge(orig_pud) || pud_devmap(orig_pud)) { if (pud_trans_huge(orig_pud) || pud_devmap(orig_pud)) {
unsigned int dirty = flags & FAULT_FLAG_WRITE;
/* NUMA case for anonymous PUDs would go here */ /* NUMA case for anonymous PUDs would go here */
@ -4020,8 +4020,7 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
if (pmd_protnone(orig_pmd) && vma_is_accessible(vma)) if (pmd_protnone(orig_pmd) && vma_is_accessible(vma))
return do_huge_pmd_numa_page(&vmf, orig_pmd); return do_huge_pmd_numa_page(&vmf, orig_pmd);
if ((vmf.flags & FAULT_FLAG_WRITE) && if (dirty && !pmd_write(orig_pmd)) {
!pmd_write(orig_pmd)) {
ret = wp_huge_pmd(&vmf, orig_pmd); ret = wp_huge_pmd(&vmf, orig_pmd);
if (!(ret & VM_FAULT_FALLBACK)) if (!(ret & VM_FAULT_FALLBACK))
return ret; return ret;