From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 25 Mar 2008 10:38:16 -0700 From: Suresh Siddha Subject: Re: [patch] srat, x86_64: Add support for nodes spanning other nodes Message-ID: <20080325173815.GJ15909@linux-os.sc.intel.com> References: <20080325171435.GA3313@linux-os.sc.intel.com> <47E93655.10907@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47E93655.10907@redhat.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Chris Snook Cc: Suresh Siddha , mingo@elte.hu, hpa@zytor.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Tue, Mar 25, 2008 at 01:28:53PM -0400, Chris Snook wrote: > Suresh Siddha wrote: > >For example, If the physical address layout on a two node system with 8 GB > >memory is something like: > >node 0: 0-2GB, 4-6GB > >node 1: 2-4GB, 6-8GB > > > >Current kernels fail to boot/detect this NUMA topology. > > > >ACPI SRAT tables can expose such a topology which needs to be supported. > > > >Signed-off-by: Suresh Siddha > >--- > > > >diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > >index 227fdb0..99eb102 100644 > >--- a/arch/x86/Kconfig > >+++ b/arch/x86/Kconfig > >@@ -880,6 +880,15 @@ config X86_64_ACPI_NUMA > > help > > Enable ACPI SRAT based node topology detection. > > > >+# Some NUMA nodes have memory ranges that span > >+# other nodes. Even though a pfn is valid and > >+# between a node's start and end pfns, it may not > >+# reside on that node. See memmap_init_zone() > >+# for details. > >+config NODES_SPAN_OTHER_NODES > >+ def_bool y > >+ depends on X86_64_ACPI_NUMA > >+ > > Is this hunk a leftover from your testing? You're not using the config No. > option anywhere, and there isn't really anything in this patch that would > justify making this a separate config option in mainline. Its the generic -mm code which needs this. Please refer to early_pfn_in_nid() and its usage in memmap_init_zone() thanks, suresh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org