From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755830AbbAOVXB (ORCPT ); Thu, 15 Jan 2015 16:23:01 -0500 Received: from www.linutronix.de ([62.245.132.108]:58434 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932192AbbAOVW6 (ORCPT ); Thu, 15 Jan 2015 16:22:58 -0500 Message-Id: <20150115211703.987833932@linutronix.de> User-Agent: quilt/0.63-1 Date: Thu, 15 Jan 2015 21:22:42 -0000 From: Thomas Gleixner To: LKML Cc: Jiang Liu , Joerg Roedel , x86@kernel.org, Tony Luck , Borislav Petkov Subject: [patch 21/23] x86/smpboot: Sanitize uniprocessor init References: <20150115210458.625399149@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=x86-smpboot-sanitize-apic-setup.patch X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The UP related setups for local apic are mangled into smp_sanity_check(). That results in duplicate calls to disable_smp() and makes the code hard to follow. Let smp_sanity_check() return dedicated values for the various exit reasons and handle them at the call site. Signed-off-by: Thomas Gleixner --- arch/x86/kernel/smpboot.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) Index: tip/arch/x86/kernel/smpboot.c =================================================================== --- tip.orig/arch/x86/kernel/smpboot.c +++ tip/arch/x86/kernel/smpboot.c @@ -990,6 +990,8 @@ void arch_disable_smp_support(void) */ static __init void disable_smp(void) { + pr_info("SMP disabled\n"); + disable_ioapic_support(); init_cpu_present(cpumask_of(0)); @@ -1003,6 +1005,13 @@ static __init void disable_smp(void) cpumask_set_cpu(0, cpu_core_mask(0)); } +enum { + SMP_OK, + SMP_NO_CONFIG, + SMP_NO_APIC, + SMP_FORCE_UP, +}; + /* * Various sanity checks. */ @@ -1050,10 +1059,7 @@ static int __init smp_sanity_check(unsig if (!smp_found_config && !acpi_lapic) { preempt_enable(); pr_notice("SMP motherboard not detected\n"); - disable_smp(); - if (APIC_init_uniprocessor()) - pr_notice("Local APIC not detected. Using dummy APIC emulation.\n"); - return -1; + return SMP_NO_CONFIG; } /* @@ -1077,7 +1083,7 @@ static int __init smp_sanity_check(unsig boot_cpu_physical_apicid); pr_err("... forcing use of dummy APIC emulation (tell your hw vendor)\n"); } - return -1; + return SMP_NO_APIC; } verify_local_APIC(); @@ -1087,12 +1093,10 @@ static int __init smp_sanity_check(unsig */ if (!max_cpus) { pr_info("SMP mode deactivated\n"); - disable_ioapic_support(); - apic_bsp_setup(); - return -1; + return SMP_FORCE_UP; } - return 0; + return SMP_OK; } static void __init smp_cpu_index_default(void) @@ -1132,10 +1136,21 @@ void __init native_smp_prepare_cpus(unsi } set_cpu_sibling_map(0); - if (smp_sanity_check(max_cpus) < 0) { - pr_info("SMP disabled\n"); + switch (smp_sanity_check(max_cpus)) { + case SMP_NO_CONFIG: disable_smp(); + if (APIC_init_uniprocessor()) + pr_notice("Local APIC not detected. Using dummy APIC emulation.\n"); + return; + case SMP_NO_APIC: + disable_smp(); + return; + case SMP_FORCE_UP: + disable_smp(); + apic_bsp_setup(); return; + case SMP_OK: + break; } default_setup_apic_routing();