Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932565AbcCCQxH (ORCPT ); Thu, 3 Mar 2016 11:53:07 -0500 Received: from mga04.intel.com ([192.55.52.120]:15178 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758242AbcCCQw6 (ORCPT ); Thu, 3 Mar 2016 11:52:58 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,532,1449561600"; d="scan'208";a="926159958" From: "Kirill A. Shutemov" To: Hugh Dickins , Andrea Arcangeli , Andrew Morton Cc: Dave Hansen , Vlastimil Babka , Christoph Lameter , Naoya Horiguchi , Jerome Marchand , Yang Shi , Sasha Levin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCHv3 21/29] vmscan: split file huge pages before paging them out Date: Thu, 3 Mar 2016 19:52:11 +0300 Message-Id: <1457023939-98083-22-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457023939-98083-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1457023939-98083-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1780 Lines: 55 This is preparation of vmscan for file huge pages. We cannot write out huge pages, so we need to split them on the way out. Signed-off-by: Kirill A. Shutemov --- mm/vmscan.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 39e90e24caff..832a00523ffb 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -473,12 +473,14 @@ void drop_slab(void) static inline int is_page_cache_freeable(struct page *page) { + int radix_tree_pins = PageTransHuge(page) ? HPAGE_PMD_NR : 1; + /* * A freeable page cache page is referenced only by the caller * that isolated the page, the page cache radix tree and * optional buffer heads at page->private. */ - return page_count(page) - page_has_private(page) == 2; + return page_count(page) - page_has_private(page) == 1 + radix_tree_pins; } static int may_write_to_inode(struct inode *inode, struct scan_control *sc) @@ -548,8 +550,6 @@ static pageout_t pageout(struct page *page, struct address_space *mapping, * swap_backing_dev_info is bust: it doesn't reflect the * congestion state of the swapdevs. Easy to fix, if needed. */ - if (!is_page_cache_freeable(page)) - return PAGE_KEEP; if (!mapping) { /* * Some data journaling orphaned pages can have @@ -1112,6 +1112,15 @@ static unsigned long shrink_page_list(struct list_head *page_list, * starts and then write it out here. */ try_to_unmap_flush_dirty(); + + if (!is_page_cache_freeable(page)) + goto keep_locked; + + if (unlikely(PageTransHuge(page))) { + if (split_huge_page_to_list(page, page_list)) + goto keep_locked; + } + switch (pageout(page, mapping, sc)) { case PAGE_KEEP: goto keep_locked; -- 2.7.0