From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f199.google.com (mail-qk0-f199.google.com [209.85.220.199]) by kanga.kvack.org (Postfix) with ESMTP id 357DB6B0397 for ; Thu, 16 Mar 2017 11:04:11 -0400 (EDT) Received: by mail-qk0-f199.google.com with SMTP id f191so41432610qka.7 for ; Thu, 16 Mar 2017 08:04:11 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id h13si1675764qth.45.2017.03.16.08.03.51 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Mar 2017 08:03:51 -0700 (PDT) From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= Subject: [HMM 02/16] mm/put_page: move ref decrement to put_zone_device_page() Date: Thu, 16 Mar 2017 12:05:21 -0400 Message-Id: <1489680335-6594-3-git-send-email-jglisse@redhat.com> In-Reply-To: <1489680335-6594-1-git-send-email-jglisse@redhat.com> References: <1489680335-6594-1-git-send-email-jglisse@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: John Hubbard , Naoya Horiguchi , David Nellans , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Dan Williams , Ross Zwisler This does not affect non ZONE_DEVICE page. In order to allow ZONE_DEVICE page to be tracked we need to detect when refcount of a ZONE_DEVICE page reach 1 (not 0 as non ZONE_DEVICE page). This patch just move put_page_testzero() from put_page() to put_zone_device_page() and only for ZONE_DEVICE. It does not add any overhead compare to existing code. Signed-off-by: JA(C)rA'me Glisse Cc: Dan Williams Cc: Ross Zwisler --- include/linux/mm.h | 8 +++++--- kernel/memremap.c | 2 ++ 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5f01c88..28e8b28 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -793,11 +793,13 @@ static inline void put_page(struct page *page) { page = compound_head(page); + if (unlikely(is_zone_device_page(page))) { + put_zone_device_page(page); + return; + } + if (put_page_testzero(page)) __put_page(page); - - if (unlikely(is_zone_device_page(page))) - put_zone_device_page(page); } #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) diff --git a/kernel/memremap.c b/kernel/memremap.c index 40d4af8..c821946 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -190,6 +190,8 @@ EXPORT_SYMBOL(get_zone_device_page); void put_zone_device_page(struct page *page) { + page_ref_dec(page); + put_dev_pagemap(page->pgmap); } EXPORT_SYMBOL(put_zone_device_page); -- 2.4.11 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org