diff options
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 39 |
1 files changed, 35 insertions, 4 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cd3fc4194733..75c0eef52c5d 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1542,7 +1542,7 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma, struct hugepage_subpool *spool = subpool_vma(vma); struct hstate *h = hstate_vma(vma); struct page *page; - long chg; + long chg, commit; int ret, idx; struct hugetlb_cgroup *h_cg; @@ -1583,7 +1583,22 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma, set_page_private(page, (unsigned long)spool); - vma_commit_reservation(h, vma, addr); + commit = vma_commit_reservation(h, vma, addr); + if (unlikely(chg > commit)) { + /* + * The page was added to the reservation map between + * vma_needs_reservation and vma_commit_reservation. + * This indicates a race with hugetlb_reserve_pages. + * Adjust for the subpool count incremented above AND + * in hugetlb_reserve_pages for the same page. Also, + * the reservation count added in hugetlb_reserve_pages + * no longer applies. + */ + long rsv_adjust; + + rsv_adjust = hugepage_subpool_put_pages(spool, 1); + hugetlb_acct_memory(h, -rsv_adjust); + } return page; out_uncharge_cgroup: @@ -3701,8 +3716,24 @@ int hugetlb_reserve_pages(struct inode *inode, * consumed reservations are stored in the map. Hence, nothing * else has to be done for private mappings here */ - if (!vma || vma->vm_flags & VM_MAYSHARE) - region_add(resv_map, from, to); + if (!vma || vma->vm_flags & VM_MAYSHARE) { + long add = region_add(resv_map, from, to); + + if (unlikely(chg > add)) { + /* + * pages in this range were added to the reserve + * map between region_chg and region_add. This + * indicates a race with alloc_huge_page. Adjust + * the subpool and reserve counts modified above + * based on the difference. + */ + long rsv_adjust; + + rsv_adjust = hugepage_subpool_put_pages(spool, + chg - add); + hugetlb_acct_memory(h, -rsv_adjust); + } + } return 0; out_err: if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) |