From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C85AC67839 for ; Fri, 14 Dec 2018 06:28:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 133F720866 for ; Fri, 14 Dec 2018 06:28:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 133F720866 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728806AbeLNG2X (ORCPT ); Fri, 14 Dec 2018 01:28:23 -0500 Received: from mga07.intel.com ([134.134.136.100]:52278 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728612AbeLNG2V (ORCPT ); Fri, 14 Dec 2018 01:28:21 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Dec 2018 22:28:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,351,1539673200"; d="scan'208";a="125841038" Received: from yhuang-mobile.sh.intel.com ([10.239.197.226]) by fmsmga002.fm.intel.com with ESMTP; 13 Dec 2018 22:28:18 -0800 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 , Daniel Jordan Subject: [PATCH -V9 14/21] swap: Support PMD swap mapping in madvise_free() Date: Fri, 14 Dec 2018 14:27:47 +0800 Message-Id: <20181214062754.13723-15-ying.huang@intel.com> X-Mailer: git-send-email 2.18.1 In-Reply-To: <20181214062754.13723-1-ying.huang@intel.com> References: <20181214062754.13723-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When madvise_free() found a PMD swap mapping, if only part of the huge swap cluster is operated on, the PMD swap mapping will be split and fallback to PTE swap mapping processing. Otherwise, if all huge swap cluster is operated on, free_swap_and_cache() will be called to decrease the PMD swap mapping count and probably free the swap space and the THP in swap cache too. 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 Cc: Daniel Jordan --- mm/huge_memory.c | 52 ++++++++++++++++++++++++++++++++++-------------- mm/madvise.c | 2 +- 2 files changed, 38 insertions(+), 16 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fdffa07bff98..c895c2a2db6e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1883,6 +1883,15 @@ int do_huge_pmd_swap_page(struct vm_fault *vmf, pmd_t orig_pmd) } #endif +static inline void zap_deposited_table(struct mm_struct *mm, pmd_t *pmd) +{ + pgtable_t pgtable; + + pgtable = pgtable_trans_huge_withdraw(mm, pmd); + pte_free(mm, pgtable); + mm_dec_nr_ptes(mm); +} + /* * Return true if we do MADV_FREE successfully on entire pmd page. * Otherwise, return false. @@ -1903,15 +1912,37 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, goto out_unlocked; orig_pmd = *pmd; - if (is_huge_zero_pmd(orig_pmd)) - goto out; - if (unlikely(!pmd_present(orig_pmd))) { - VM_BUG_ON(thp_migration_supported() && - !is_pmd_migration_entry(orig_pmd)); - goto out; + swp_entry_t entry = pmd_to_swp_entry(orig_pmd); + + if (is_migration_entry(entry)) { + VM_BUG_ON(!thp_migration_supported()); + goto out; + } else if (IS_ENABLED(CONFIG_THP_SWAP) && + !non_swap_entry(entry)) { + /* + * If part of THP is discarded, split the PMD + * swap mapping and operate on the PTEs + */ + if (next - addr != HPAGE_PMD_SIZE) { + __split_huge_swap_pmd(vma, addr, pmd); + goto out; + } + free_swap_and_cache(entry, HPAGE_PMD_NR); + pmd_clear(pmd); + zap_deposited_table(mm, pmd); + if (current->mm == mm) + sync_mm_rss(mm); + add_mm_counter(mm, MM_SWAPENTS, -HPAGE_PMD_NR); + ret = true; + goto out; + } else + VM_BUG_ON(1); } + if (is_huge_zero_pmd(orig_pmd)) + goto out; + page = pmd_page(orig_pmd); /* * If other processes are mapping this page, we couldn't discard @@ -1957,15 +1988,6 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, return ret; } -static inline void zap_deposited_table(struct mm_struct *mm, pmd_t *pmd) -{ - pgtable_t pgtable; - - pgtable = pgtable_trans_huge_withdraw(mm, pmd); - pte_free(mm, pgtable); - mm_dec_nr_ptes(mm); -} - int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr) { diff --git a/mm/madvise.c b/mm/madvise.c index fac48161b015..c1845dab2dd4 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -321,7 +321,7 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, unsigned long next; next = pmd_addr_end(addr, end); - if (pmd_trans_huge(*pmd)) + if (pmd_trans_huge(*pmd) || is_swap_pmd(*pmd)) if (madvise_free_huge_pmd(tlb, vma, pmd, addr, next)) goto next; -- 2.18.1