diff options
| author | Andrea Arcangeli <aarcange@redhat.com> | 2010-10-15 01:38:21 +0200 |
|---|---|---|
| committer | Andrea Arcangeli <aarcange@redhat.com> | 2010-10-14 23:40:14 +0000 |
| commit | af5cb7171049f82f34485ef225589c712e328e03 (patch) | |
| tree | e1632d24db0fb498bc3e5aa569915358abe76224 | |
| parent | 6e187855633600302853c1065ce02389a2ad45a8 (diff) | |
add debug checks for mapcount related invariantsTHP-31
Add debug checks for invariants that if broken could lead to mapcount vs
page_mapcount debug checks to trigger later in split_huge_page.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
| -rw-r--r-- | mm/memory.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/memory.c b/mm/memory.c index 175f040d7ba9..87072b9b5080 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -804,6 +804,7 @@ static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src next = pmd_addr_end(addr, end); if (pmd_trans_huge(*src_pmd)) { int err; + VM_BUG_ON(next-addr != HPAGE_PMD_SIZE); err = copy_huge_pmd(dst_mm, src_mm, dst_pmd, src_pmd, addr, vma); if (err == -ENOMEM) @@ -1015,9 +1016,10 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb, do { next = pmd_addr_end(addr, end); if (pmd_trans_huge(*pmd)) { - if (next-addr != HPAGE_PMD_SIZE) + if (next-addr != HPAGE_PMD_SIZE) { + VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem)); split_huge_page_pmd(vma->vm_mm, pmd); - else if (zap_huge_pmd(tlb, vma, pmd)) { + } else if (zap_huge_pmd(tlb, vma, pmd)) { (*zap_work)--; continue; } |