Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756026AbYJIPzL (ORCPT ); Thu, 9 Oct 2008 11:55:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752404AbYJIPy7 (ORCPT ); Thu, 9 Oct 2008 11:54:59 -0400 Received: from hera.kernel.org ([140.211.167.34]:60122 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752129AbYJIPy6 (ORCPT ); Thu, 9 Oct 2008 11:54:58 -0400 Message-ID: <48EE291F.2010704@kernel.org> Date: Thu, 09 Oct 2008 08:54:07 -0700 From: Yinghai Lu User-Agent: Thunderbird 2.0.0.17 (X11/20080922) MIME-Version: 1.0 To: bibo mao CC: linux-kernel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: [patch 1/1] combine two adjacent mtrr region with the same type References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2746 Lines: 77 bibo mao wrote: > This patch is to combine two adjacent mtrr region with the same type. > > kernel/cpu/mtrr/main.c | 17 +++++++++++++++-- > 3 files changed, 15 insertions(+), 2 deletions(-) > > Signed-off-by: bibo mao > > ------------------------------------------------------------------------------- > diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c > index 6e212f3..c3adf83 100644 > --- a/arch/x86/kernel/cpu/mtrr/main.c > +++ b/arch/x86/kernel/cpu/mtrr/main.c > @@ -305,7 +305,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, > { > int i, j, replace, error; > mtrr_type ltype; > - unsigned long lbase, lsize; > + unsigned long lbase, lsize, newbase; > > if (!mtrr_if) > return -ENXIO; > @@ -344,7 +344,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, > mutex_lock(&mtrr_mutex); > for (i = 0; i < num_var_ranges; ++i) { > mtrr_if->get(i, &lbase, &lsize, <ype); > - if (!lsize || base > lbase + lsize - 1 || base + size - 1 < lbase) > + if (!lsize || base > lbase + lsize || base + size < lbase) > continue; > /* At this point we know there is some kind of overlap/enclosure */ > if (base < lbase || base + size - 1 > lbase + lsize - 1) { > @@ -356,6 +356,19 @@ int mtrr_add_page(unsigned long base, unsigned long size, > } > else if (types_compatible(type, ltype)) > continue; > + } else if ((base == lbase + lsize) || (lbase ==base + size)) { > + if (type != ltype) > + continue; this path seems not right... do you need if (ltype != type) { if (types_compatible(type, ltype)) continue; printk (KERN_WARNING "mtrr: type mismatch for %lx000,%lx000 old: %s new: %s\n", base, size, mtrr_attrib_to_str(ltype), mtrr_attrib_to_str(type)); goto out; } ? > + /* New region adjacent with an existing region */ > + newbase = (base < lbase) ? base : lbase; > + if (!mtrr_if->validate_add_page(newbase,lsize + size,type) && > + mtrr_if->get_free_region(newbase, lsize + size, replace)>=0) { > + base = newbase; > + size += lsize; > + replace = i; > + continue; > + } else > + continue; > } > printk(KERN_WARNING > "mtrr: 0x%lx000,0x%lx000 overlaps existing" better to have some test case... YH -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/