From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754466Ab0IIL62 (ORCPT ); Thu, 9 Sep 2010 07:58:28 -0400 Received: from hera.kernel.org ([140.211.167.34]:34227 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752109Ab0IIL6Y (ORCPT ); Thu, 9 Sep 2010 07:58:24 -0400 Date: Thu, 9 Sep 2010 11:57:57 GMT From: tip-bot for Cliff Wickman Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, cpw@sgi.com, tglx@linutronix.de, mingo@elte.hu, ebiederm@xmission.com Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, cpw@sgi.com, tglx@linutronix.de, ebiederm@xmission.com, mingo@elte.hu In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/mm] x86, kdump: Change copy_oldmem_page() to use cached addressing Message-ID: Git-Commit-ID: 37a2f9f30a360fb03522d15c85c78265ccd80287 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 09 Sep 2010 11:57:58 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 37a2f9f30a360fb03522d15c85c78265ccd80287 Gitweb: http://git.kernel.org/tip/37a2f9f30a360fb03522d15c85c78265ccd80287 Author: Cliff Wickman AuthorDate: Wed, 8 Sep 2010 10:14:27 -0500 Committer: Ingo Molnar CommitDate: Thu, 9 Sep 2010 09:46:23 +0200 x86, kdump: Change copy_oldmem_page() to use cached addressing The copy of /proc/vmcore to a user buffer proceeds much faster if the kernel addresses memory as cached. With this patch we have seen an increase in transfer rate from less than 15MB/s to 80-460MB/s, depending on size of the transfer. This makes a big difference in time needed to save a system dump. Signed-off-by: Cliff Wickman Acked-by: "Eric W. Biederman" Cc: kexec@lists.infradead.org Cc: # as far back as it would apply LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/crash_dump_64.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c index 045b36c..bf43188 100644 --- a/arch/x86/kernel/crash_dump_64.c +++ b/arch/x86/kernel/crash_dump_64.c @@ -34,7 +34,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; - vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE); + vaddr = ioremap_cache(pfn << PAGE_SHIFT, PAGE_SIZE); if (!vaddr) return -ENOMEM;