+ mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch added to -mm tree

+ mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch added to -mm tree

[akpm]

Subject: + mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch added to -mm tree
To: iamjoonsoo.kim@lge.com,aneesh.kumar@linux.vnet.ibm.com,david@gibson.dropbear.id.au,davidlohr@hp.com,dhillf@gmail.com,liwanp@linux.vnet.ibm.com,n-horiguchi@ah.jp.nec.com
From: akpm@linux-foundation.org
Date: Wed, 14 Aug 2013 16:21:10 -0700


The patch titled
     Subject: mm, hugetlb: protect reserved pages when soft offlining a hugepage
has been added to the -mm tree.  Its filename is
     mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch

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------------------------------------------------------
From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: mm, hugetlb: protect reserved pages when soft offlining a hugepage

Don't use the reserve pool when soft offlining a hugepage.  Check we have
free pages outside the reserve pool before we dequeue the huge page. 
Otherwise, we can steal other's reserve page.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff -puN mm/hugetlb.c~mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage mm/hugetlb.c
--- a/mm/hugetlb.c~mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage
+++ a/mm/hugetlb.c
@@ -955,10 +955,11 @@ static struct page *alloc_buddy_huge_pag
  */
 struct page *alloc_huge_page_node(struct hstate *h, int nid)
 {
-	struct page *page;
+	struct page *page = NULL;
 
 	spin_lock(&hugetlb_lock);
-	page = dequeue_huge_page_node(h, nid);
+	if (h->free_huge_pages - h->resv_huge_pages > 0)
+		page = dequeue_huge_page_node(h, nid);
 	spin_unlock(&hugetlb_lock);
 
 	if (!page)
_

Patches currently in -mm which might be from iamjoonsoo.kim@lge.com are

mm-hugetlb-move-up-the-code-which-check-availability-of-free-huge-page.patch
mm-hugetlb-trivial-commenting-fix.patch
mm-hugetlb-clean-up-alloc_huge_page.patch
mm-hugetlb-fix-and-clean-up-node-iteration-code-to-alloc-or-free.patch
mm-hugetlb-remove-redundant-list_empty-check-in-gather_surplus_pages.patch
mm-hugetlb-do-not-use-a-page-in-page-cache-for-cow-optimization.patch
mm-hugetlb-add-vm_noreserve-check-in-vma_has_reserves.patch
mm-hugetlb-remove-decrement_hugepage_resv_vma.patch
mm-hugetlb-decrement-reserve-count-if-vm_noreserve-alloc-page-cache.patch
mm-hugetlb-decrement-reserve-count-if-vm_noreserve-alloc-page-cache-fix.patch
mm-page_alloc-add-unlikely-macro-to-help-compiler-optimization.patch
mm-move-pgtable-related-functions-to-right-place.patch
swap-clean-up-ifdef-in-page_mapping.patch
mm-vmalloc-remove-useless-variable-in-vmap_block.patch
mm-vmalloc-use-well-defined-find_last_bit-func.patch
mm-hugetlb-protect-reserved-pages-when-soft-offlining-a-hugepage.patch
mm-hugetlb-change-variable-name-reservations-to-resv.patch
mm-hugetlb-fix-subpool-accounting-handling.patch
mm-hugetlb-remove-useless-check-about-mapping-type.patch
mm-hugetlb-grab-a-page_table_lock-after-page_cache_release.patch
mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed.patch
linux-next.patch