Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423031Ab3CVU1l (ORCPT ); Fri, 22 Mar 2013 16:27:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58892 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422907Ab3CVUZS (ORCPT ); Fri, 22 Mar 2013 16:25:18 -0400 From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , Mel Gorman , Hugh Dickins , KOSAKI Motohiro , Andi Kleen , Hillf Danton , Michal Hocko , linux-kernel@vger.kernel.org Subject: [PATCH 06/10] migrate: add hugepage migration code to move_pages() Date: Fri, 22 Mar 2013 16:23:51 -0400 Message-Id: <1363983835-20184-7-git-send-email-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1363983835-20184-1-git-send-email-n-horiguchi@ah.jp.nec.com> References: <1363983835-20184-1-git-send-email-n-horiguchi@ah.jp.nec.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3407 Lines: 110 This patch extends move_pages() to handle vma with VM_HUGETLB set. We will be able to migrate hugepage with move_pages(2) after applying the enablement patch which comes later in this series. We avoid getting refcount on tail pages of hugepage, because unlike thp, hugepage is not split and we need not care about races with splitting. And migration of larger (1GB for x86_64) hugepage are not enabled. ChangeLog v2: - updated description and renamed patch title Signed-off-by: Naoya Horiguchi --- mm/memory.c | 6 ++++-- mm/migrate.c | 26 +++++++++++++++++++------- 2 files changed, 23 insertions(+), 9 deletions(-) diff --git v3.9-rc3.orig/mm/memory.c v3.9-rc3/mm/memory.c index 494526a..3b6ad3d 100644 --- v3.9-rc3.orig/mm/memory.c +++ v3.9-rc3/mm/memory.c @@ -1503,7 +1503,8 @@ struct page *follow_page_mask(struct vm_area_struct *vma, if (pud_none(*pud)) goto no_page_table; if (pud_huge(*pud) && vma->vm_flags & VM_HUGETLB) { - BUG_ON(flags & FOLL_GET); + if (flags & FOLL_GET) + goto out; page = follow_huge_pud(mm, address, pud, flags & FOLL_WRITE); goto out; } @@ -1514,8 +1515,9 @@ struct page *follow_page_mask(struct vm_area_struct *vma, if (pmd_none(*pmd)) goto no_page_table; if (pmd_huge(*pmd) && vma->vm_flags & VM_HUGETLB) { - BUG_ON(flags & FOLL_GET); page = follow_huge_pmd(mm, address, pmd, flags & FOLL_WRITE); + if (flags & FOLL_GET && PageHead(page)) + get_page_foll(page); goto out; } if ((flags & FOLL_NUMA) && pmd_numa(*pmd)) diff --git v3.9-rc3.orig/mm/migrate.c v3.9-rc3/mm/migrate.c index 38912ae..ef8e4e3 100644 --- v3.9-rc3.orig/mm/migrate.c +++ v3.9-rc3/mm/migrate.c @@ -1104,7 +1104,11 @@ static struct page *new_page_node(struct page *p, unsigned long private, *result = &pm->status; - return alloc_pages_exact_node(pm->node, + if (PageHuge(p)) + return alloc_huge_page_node(page_hstate(compound_head(p)), + pm->node); + else + return alloc_pages_exact_node(pm->node, GFP_HIGHUSER_MOVABLE | GFP_THISNODE, 0); } @@ -1150,6 +1154,13 @@ static int do_move_page_to_node_array(struct mm_struct *mm, if (PageReserved(page)) goto put_and_set; + /* + * follow_page(FOLL_GET) didn't get refcount for tail pages of + * hugepage, so here we skip putting it. + */ + if (PageHuge(page) && PageTail(page)) + goto set_status; + pp->page = page; err = page_to_nid(page); @@ -1164,6 +1175,12 @@ static int do_move_page_to_node_array(struct mm_struct *mm, !migrate_all) goto put_and_set; + if (PageHuge(page)) { + get_page(page); + list_move_tail(&page->lru, &pagelist); + goto put_and_set; + } + err = isolate_lru_page(page); if (!err) { list_add_tail(&page->lru, &pagelist); @@ -1181,13 +1198,8 @@ static int do_move_page_to_node_array(struct mm_struct *mm, pp->status = err; } - err = 0; - if (!list_empty(&pagelist)) { - err = migrate_pages(&pagelist, new_page_node, + err = migrate_movable_pages(&pagelist, new_page_node, (unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL); - if (err) - putback_lru_pages(&pagelist); - } up_read(&mm->mmap_sem); return err; -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/