From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f69.google.com (mail-pl0-f69.google.com [209.85.160.69]) by kanga.kvack.org (Postfix) with ESMTP id 22B206B0022 for ; Sun, 25 Mar 2018 22:58:51 -0400 (EDT) Received: by mail-pl0-f69.google.com with SMTP id w19-v6so12100029plq.2 for ; Sun, 25 Mar 2018 19:58:51 -0700 (PDT) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTPS id u126si9687952pgb.628.2018.03.25.19.58.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 25 Mar 2018 19:58:50 -0700 (PDT) From: Wei Wang Subject: [PATCH v29 3/4] mm/page_poison: expose page_poisoning_enabled to kernel modules Date: Mon, 26 Mar 2018 10:39:53 +0800 Message-Id: <1522031994-7246-4-git-send-email-wei.w.wang@intel.com> In-Reply-To: <1522031994-7246-1-git-send-email-wei.w.wang@intel.com> References: <1522031994-7246-1-git-send-email-wei.w.wang@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mhocko@kernel.org, akpm@linux-foundation.org Cc: pbonzini@redhat.com, wei.w.wang@intel.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, riel@redhat.com, huangzhichao@huawei.com In some usages, e.g. virtio-balloon, a kernel module needs to know if page poisoning is in use. This patch exposes the page_poisoning_enabled function to kernel modules. Signed-off-by: Wei Wang Cc: Andrew Morton Cc: Michal Hocko Cc: Michael S. Tsirkin --- mm/page_poison.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/page_poison.c b/mm/page_poison.c index e83fd44..762b472 100644 --- a/mm/page_poison.c +++ b/mm/page_poison.c @@ -17,6 +17,11 @@ static int early_page_poison_param(char *buf) } early_param("page_poison", early_page_poison_param); +/** + * page_poisoning_enabled - check if page poisoning is enabled + * + * Return true if page poisoning is enabled, or false if not. + */ bool page_poisoning_enabled(void) { /* @@ -29,6 +34,7 @@ bool page_poisoning_enabled(void) (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) && debug_pagealloc_enabled())); } +EXPORT_SYMBOL_GPL(page_poisoning_enabled); static void poison_page(struct page *page) { -- 2.7.4