From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934293AbeEIIkL (ORCPT ); Wed, 9 May 2018 04:40:11 -0400 Received: from mga14.intel.com ([192.55.52.115]:19279 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934277AbeEIIkE (ORCPT ); Wed, 9 May 2018 04:40:04 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,381,1520924400"; d="scan'208";a="52769769" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , "Kirill A. Shutemov" , Andrea Arcangeli , Michal Hocko , Johannes Weiner , Shaohua Li , Hugh Dickins , Minchan Kim , Rik van Riel , Dave Hansen , Naoya Horiguchi , Zi Yan Subject: [PATCH -mm -V2 17/21] mm, THP, swap: Support PMD swap mapping for MADV_WILLNEED Date: Wed, 9 May 2018 16:38:42 +0800 Message-Id: <20180509083846.14823-18-ying.huang@intel.com> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180509083846.14823-1-ying.huang@intel.com> References: <20180509083846.14823-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Ying During MADV_WILLNEED, for a PMD swap mapping, if THP swapin is enabled for the VMA, the whole swap cluster will be swapin. Otherwise, the huge swap cluster and the PMD swap mapping will be split and fallback to PTE swap mapping. Signed-off-by: "Huang, Ying" Cc: "Kirill A. Shutemov" Cc: Andrea Arcangeli Cc: Michal Hocko Cc: Johannes Weiner Cc: Shaohua Li Cc: Hugh Dickins Cc: Minchan Kim Cc: Rik van Riel Cc: Dave Hansen Cc: Naoya Horiguchi Cc: Zi Yan --- mm/madvise.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index e03e85a20fb4..44a0a62f4848 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -196,14 +196,36 @@ static int swapin_walk_pmd_entry(pmd_t *pmd, unsigned long start, pte_t *orig_pte; struct vm_area_struct *vma = walk->private; unsigned long index; + swp_entry_t entry; + struct page *page; + pmd_t pmdval; + + pmdval = *pmd; + if (thp_swap_supported() && is_swap_pmd(pmdval) && + !is_pmd_migration_entry(pmdval)) { + entry = pmd_to_swp_entry(pmdval); + if (!transparent_hugepage_swapin_enabled(vma)) { + if (!split_swap_cluster(entry, false)) + split_huge_swap_pmd(vma, pmd, start, pmdval); + } else { + page = read_swap_cache_async(entry, + GFP_HIGHUSER_MOVABLE, + vma, start, false); + /* The swap cluster has been split under us */ + if (page) { + if (!PageTransHuge(page)) + split_huge_swap_pmd(vma, pmd, start, + pmdval); + put_page(page); + } + } + } if (pmd_none_or_trans_huge_or_clear_bad(pmd)) return 0; for (index = start; index != end; index += PAGE_SIZE) { pte_t pte; - swp_entry_t entry; - struct page *page; spinlock_t *ptl; orig_pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl); -- 2.16.1