diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 83326ad66d9b..615d9743a3cb 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1139,7 +1139,7 @@ static int __split_huge_page_splitting(struct page *page, * We can't temporarily set the pmd to null in order * to split it, the pmd must remain marked huge at all * times or the VM won't take the pmd_trans_huge paths - * and it won't wait on the anon_vma->root->lock to + * and it won't wait on the anon_vma->root->mutex to * serialize against split_huge_page*. */ pmdp_splitting_flush_notify(vma, address, pmd); @@ -1333,7 +1333,7 @@ static int __split_huge_page_map(struct page *page, return ret; } -/* must be called with anon_vma->root->lock hold */ +/* must be called with anon_vma->root->mutex hold */ static void __split_huge_page(struct page *page, struct anon_vma *anon_vma) { @@ -1771,12 +1771,9 @@ static void collapse_huge_page(struct mm_struct *mm, VM_BUG_ON(address & ~HPAGE_PMD_MASK); #ifndef CONFIG_NUMA + up_read(&mm->mmap_sem); VM_BUG_ON(!*hpage); new_page = *hpage; - if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { - up_read(&mm->mmap_sem); - return; - } #else VM_BUG_ON(*hpage); /* @@ -1791,22 +1788,26 @@ static void collapse_huge_page(struct mm_struct *mm, */ new_page = alloc_hugepage_vma(khugepaged_defrag(), vma, address, node, __GFP_OTHER_NODE); + + /* + * After allocating the hugepage, release the mmap_sem read lock in + * preparation for taking it in write mode. + */ + up_read(&mm->mmap_sem); if (unlikely(!new_page)) { - up_read(&mm->mmap_sem); count_vm_event(THP_COLLAPSE_ALLOC_FAILED); *hpage = ERR_PTR(-ENOMEM); return; } +#endif + count_vm_event(THP_COLLAPSE_ALLOC); if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { - up_read(&mm->mmap_sem); +#ifdef CONFIG_NUMA put_page(new_page); +#endif return; } -#endif - - /* after allocating the hugepage upgrade to mmap_sem write mode */ - up_read(&mm->mmap_sem); /* * Prevent all access to pagetables with the exception of |