From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751342AbbJBFkW (ORCPT ); Fri, 2 Oct 2015 01:40:22 -0400 Received: from mga02.intel.com ([134.134.136.20]:25046 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750767AbbJBFkU (ORCPT ); Fri, 2 Oct 2015 01:40:20 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,621,1437462000"; d="scan'208";a="572596848" From: "Kirill A. Shutemov" To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCH 3/3] page-flags: hide PF_* validation check under separate config option Date: Fri, 2 Oct 2015 08:40:16 +0300 Message-Id: <1443764416-129688-4-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.5.1 In-Reply-To: <1443764416-129688-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1443764416-129688-1-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 VM_BUG_ONs in PF_NO_TAIL() and PF_NO_COMPOUND() add 4+ KiB to mm/build-in.o for DEBUG_VM kernel. Let's hide them under new config option -- CONFIG_DEBUG_VM_PGFLAGS. With the option enabled VM_BUG_ON_PGFLAGS() is equal to VM_BUG_ON_PAGE. Signed-off-by: Kirill A. Shutemov --- include/linux/mmdebug.h | 6 ++++++ include/linux/page-flags.h | 8 +++----- lib/Kconfig.debug | 8 ++++++++ 3 files changed, 17 insertions(+), 5 deletions(-) diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h index 877ef226f90f..c447d8055e50 100644 --- a/include/linux/mmdebug.h +++ b/include/linux/mmdebug.h @@ -55,4 +55,10 @@ void dump_mm(const struct mm_struct *mm); #define VIRTUAL_BUG_ON(cond) do { } while (0) #endif +#ifdef CONFIG_DEBUG_VM_PGFLAGS +#define VM_BUG_ON_PGFLAGS(cond, page) VM_BUG_ON_PAGE(cond, page) +#else +#define VM_BUG_ON_PGFLAGS(cond, page) BUILD_BUG_ON_INVALID(cond) +#endif + #endif diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 19e4129f00e5..8d6e4e9a98af 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -153,12 +153,10 @@ enum pageflags { #define PF_ANY(page, enforce) page #define PF_HEAD(page, enforce) compound_head(page) #define PF_NO_TAIL(page, enforce) ({ \ - if (enforce) \ - VM_BUG_ON_PAGE(PageTail(page), page); \ + VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \ compound_head(page);}) -#define PF_NO_COMPOUND(page, enforce) ({ \ - if (enforce) \ - VM_BUG_ON_PAGE(PageCompound(page), page); \ +#define PF_NO_COMPOUND(page, enforce) ({ \ + VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \ page;}) /* diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index e2894b23efb6..0d12bfa429de 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -570,6 +570,14 @@ config DEBUG_VM_RB If unsure, say N. +config DEBUG_VM_PGFLAGS + bool "Debug page-flags operations" + depends on DEBUG_VM + help + Enables extra validation on page flags operations. + + If unsure, say N. + config DEBUG_VIRTUAL bool "Debug VM translations" depends on DEBUG_KERNEL && X86 -- 2.5.1