thp: mincore transparent hugepage support

Handle transparent huge page pmd entries natively instead of splitting
them into subpages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner
2011-01-13 15:47:02 -08:00
committed by Linus Torvalds
parent f2d6bfe9ff
commit 0ca1634d41
3 changed files with 35 additions and 1 deletions

View File

@@ -923,6 +923,31 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
return ret;
}
int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end,
unsigned char *vec)
{
int ret = 0;
spin_lock(&vma->vm_mm->page_table_lock);
if (likely(pmd_trans_huge(*pmd))) {
ret = !pmd_trans_splitting(*pmd);
spin_unlock(&vma->vm_mm->page_table_lock);
if (unlikely(!ret))
wait_split_huge_page(vma->anon_vma, pmd);
else {
/*
* All logical pages in the range are present
* if backed by a huge page.
*/
memset(vec, 1, (end - addr) >> PAGE_SHIFT);
}
} else
spin_unlock(&vma->vm_mm->page_table_lock);
return ret;
}
pmd_t *page_check_address_pmd(struct page *page,
struct mm_struct *mm,
unsigned long address,