Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754358AbZFUIUP (ORCPT ); Sun, 21 Jun 2009 04:20:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751708AbZFUIT6 (ORCPT ); Sun, 21 Jun 2009 04:19:58 -0400 Received: from hera.kernel.org ([140.211.167.34]:51287 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751244AbZFUITy (ORCPT ); Sun, 21 Jun 2009 04:19:54 -0400 Date: Sun, 21 Jun 2009 08:18:37 GMT From: tip-bot for Andreas Herrmann To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, andreas.herrmann3@amd.com, stable@kernel.org, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, andreas.herrmann3@amd.com, stable@kernel.org, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <20090619085909.GJ5218@alberich.amd.com> References: <20090619085909.GJ5218@alberich.amd.com> Subject: [tip:x86/urgent] x86: Set cpu_llc_id on AMD CPUs Message-ID: Git-Commit-ID: 99bd0c0fc4b04da54cb311953ef9489931c19c63 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-4.0 (hera.kernel.org [127.0.0.1]); Sun, 21 Jun 2009 08:18:37 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2534 Lines: 84 Commit-ID: 99bd0c0fc4b04da54cb311953ef9489931c19c63 Gitweb: http://git.kernel.org/tip/99bd0c0fc4b04da54cb311953ef9489931c19c63 Author: Andreas Herrmann AuthorDate: Fri, 19 Jun 2009 10:59:09 +0200 Committer: Ingo Molnar CommitDate: Sun, 21 Jun 2009 10:13:32 +0200 x86: Set cpu_llc_id on AMD CPUs This counts when building sched domains in case NUMA information is not available. ( See cpu_coregroup_mask() which uses llc_shared_map which in turn is created based on cpu_llc_id. ) Currently Linux builds domains as follows: (example from a dual socket quad-core system) CPU0 attaching sched-domain: domain 0: span 0-7 level CPU groups: 0 1 2 3 4 5 6 7 ... CPU7 attaching sched-domain: domain 0: span 0-7 level CPU groups: 7 0 1 2 3 4 5 6 Ever since that is borked for multi-core AMD CPU systems. This patch fixes that and now we get a proper: CPU0 attaching sched-domain: domain 0: span 0-3 level MC groups: 0 1 2 3 domain 1: span 0-7 level CPU groups: 0-3 4-7 ... CPU7 attaching sched-domain: domain 0: span 4-7 level MC groups: 7 4 5 6 domain 1: span 0-7 level CPU groups: 4-7 0-3 This allows scheduler to assign tasks to cores on different sockets (i.e. that don't share last level cache) for performance reasons. Signed-off-by: Andreas Herrmann LKML-Reference: <20090619085909.GJ5218@alberich.amd.com> Cc: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/amd.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index e5b27d8..28e5f59 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -258,13 +258,15 @@ static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c) { #ifdef CONFIG_X86_HT unsigned bits; + int cpu = smp_processor_id(); bits = c->x86_coreid_bits; - /* Low order bits define the core id (index of core in socket) */ c->cpu_core_id = c->initial_apicid & ((1 << bits)-1); /* Convert the initial APIC ID into the socket ID */ c->phys_proc_id = c->initial_apicid >> bits; + /* use socket ID also for last level cache */ + per_cpu(cpu_llc_id, cpu) = c->phys_proc_id; #endif } -- 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/