From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752681AbbIHCqq (ORCPT ); Mon, 7 Sep 2015 22:46:46 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:13366 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752466AbbIHCqM (ORCPT ); Mon, 7 Sep 2015 22:46:12 -0400 Message-ID: <55EE4BD2.3080800@huawei.com> Date: Tue, 8 Sep 2015 10:45:38 +0800 From: Zhang Zhen User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20121010 Thunderbird/16.0.1 MIME-Version: 1.0 To: , , , , CC: , Linux Kernel Mailing List Subject: [PATCH] ARM:mm: define arch-specific IOREMAP_MAX_ORDER only in !SMP && !LPAE case References: <1441680050-50490-1-git-send-email-zhenzhang.zhang@huawei.com> In-Reply-To: <1441680050-50490-1-git-send-email-zhenzhang.zhang@huawei.com> X-Forwarded-Message-Id: <1441680050-50490-1-git-send-email-zhenzhang.zhang@huawei.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.111.68.57] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The arch-specific IOREMAP_MAX_ORDER is introduced in commit: ff0daca([ARM] Add section support to ioremap) and commit: a069c89 ([ARM] 3705/1: add supersection support to ioremap()). But supersections and sections mappings are only used in !SMP && !LPAE case. Otherwise, mapping is created using the usual 4K pages. In most cases without !SMP && !LPAE, the big alignment cause high fragmentation issue in vmalloc area. Here we use arch-specific IOREMAP_MAX_ORDER only in !SMP && !LPAE case, otherwise use generic IOREMAP_MAX_ORDER in include/linux/vmalloc.h. Signed-off-by: Zhang Zhen --- arch/arm/include/asm/memory.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index b7f6fb4..3209012 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -76,10 +76,12 @@ */ #define XIP_VIRT_ADDR(physaddr) (MODULES_VADDR + ((physaddr) & 0x000fffff)) +#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) /* * Allow 16MB-aligned ioremap pages */ #define IOREMAP_MAX_ORDER 24 +#endif #else /* CONFIG_MMU */ -- 1.9.1 .