diff options
author | Johannes Weiner <hannes@cmpxchg.org> | 2011-01-13 15:47:02 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-13 17:32:44 -0800 |
commit | 0ca1634d4143c3579273ca53b993df19f5c98e92 (patch) | |
tree | d566a582357a9e1528d1783566bfda4375c7e566 /mm/huge_memory.c | |
parent | f2d6bfe9ff0acec30b713614260e78b03d20e909 (diff) | |
download | lwn-0ca1634d4143c3579273ca53b993df19f5c98e92.tar.gz lwn-0ca1634d4143c3579273ca53b993df19f5c98e92.zip |
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>
Diffstat (limited to 'mm/huge_memory.c')
-rw-r--r-- | mm/huge_memory.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ae2bf08b1099..37e89a32a0b1 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -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, |