Subject: + mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed.patch added to -mm tree To: iamjoonsoo.kim@xxxxxxx,aneesh.kumar@xxxxxxxxxxxxxxxxxx,david@xxxxxxxxxxxxxxxxxxxxx,davidlohr@xxxxxx,dhillf@xxxxxxxxx,liwanp@xxxxxxxxxxxxxxxxxx,n-horiguchi@xxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Wed, 14 Aug 2013 16:21:15 -0700 The patch titled Subject: mm, hugetlb: return a reserved page to a reserved pool if failed has been added to the -mm tree. Its filename is mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Subject: mm, hugetlb: return a reserved page to a reserved pool if failed If we fail with a reserved page, just calling put_page() is not sufficient, because put_page() invoke free_huge_page() at last step and it doesn't know whether a page comes from a reserved pool or not. So it doesn't do anything related to reserved count. This makes reserve count lower than how we need, because reserve count already decrease in dequeue_huge_page_vma(). This patch fix this situation. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Aneesh Kumar <aneesh.kumar@xxxxxxxxxxxxxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: Davidlohr Bueso <davidlohr@xxxxxx> Cc: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx> Cc: Wanpeng Li <liwanp@xxxxxxxxxxxxxxxxxx> Cc: Hillf Danton <dhillf@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff -puN mm/hugetlb.c~mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed mm/hugetlb.c --- a/mm/hugetlb.c~mm-hugetlb-return-a-reserved-page-to-a-reserved-pool-if-failed +++ a/mm/hugetlb.c @@ -572,6 +572,7 @@ retry_cpuset: if (!vma_has_reserves(vma, chg)) break; + SetPagePrivate(page); h->resv_huge_pages--; break; } @@ -629,15 +630,20 @@ static void free_huge_page(struct page * int nid = page_to_nid(page); struct hugepage_subpool *spool = (struct hugepage_subpool *)page_private(page); + bool restore_reserve; set_page_private(page, 0); page->mapping = NULL; BUG_ON(page_count(page)); BUG_ON(page_mapcount(page)); + restore_reserve = PagePrivate(page); spin_lock(&hugetlb_lock); hugetlb_cgroup_uncharge_page(hstate_index(h), pages_per_huge_page(h), page); + if (restore_reserve) + h->resv_huge_pages++; + if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) { /* remove the page from active list */ list_del(&page->lru); @@ -2636,6 +2642,8 @@ retry_avoidcopy: spin_lock(&mm->page_table_lock); ptep = huge_pte_offset(mm, address & huge_page_mask(h)); if (likely(pte_same(huge_ptep_get(ptep), pte))) { + ClearPagePrivate(new_page); + /* Break COW */ huge_ptep_clear_flush(vma, address, ptep); set_huge_pte_at(mm, address, ptep, @@ -2747,6 +2755,7 @@ retry: goto retry; goto out; } + ClearPagePrivate(page); spin_lock(&inode->i_lock); inode->i_blocks += blocks_per_huge_page(h); @@ -2793,8 +2802,10 @@ retry: if (!huge_pte_none(huge_ptep_get(ptep))) goto backout; - if (anon_rmap) + if (anon_rmap) { + ClearPagePrivate(page); hugepage_add_new_anon_rmap(page, vma, address); + } else page_dup_rmap(page); new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) _ Patches currently in -mm which might be from iamjoonsoo.kim@xxxxxxx 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 -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html