Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756685AbbGGJac (ORCPT ); Tue, 7 Jul 2015 05:30:32 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:50400 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754092AbbGGJaS (ORCPT ); Tue, 7 Jul 2015 05:30:18 -0400 X-IronPort-AV: E=Sophos;i="5.13,665,1427731200"; d="scan'208";a="98166909" From: Tang Chen To: , , , , , , , , , , , CC: , , , , , Gu Zheng Subject: [PATCH 3/5] x86, acpi, cpu-hotplug: Introduce apicid_to_cpuid[] array to store persistent cpuid <-> apicid mapping. Date: Tue, 7 Jul 2015 17:30:23 +0800 Message-ID: <1436261425-29881-4-git-send-email-tangchen@cn.fujitsu.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1436261425-29881-1-git-send-email-tangchen@cn.fujitsu.com> References: <1436261425-29881-1-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.167.226.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4045 Lines: 137 From: Gu Zheng In this patch, we introduce a new static array named apicid_to_cpuid[], which is large enough to store info for all possible cpus. And then, we modify the cpuid calculation. In generic_processor_info(), it simply finds the next unused cpuid. And it is also why the cpuid <-> nodeid mapping changes with node hotplug. After this patch, we find the next unused cpuid, map it to an apicid, and store the mapping in apicid_to_cpuid[], so that cpuid <-> apicid mapping will be persistent. And finally we will use this array to make cpuid <-> nodeid persistent. cpuid <-> apicid mapping is established at local apic registeration time. But non-present or disabled cpus are ignored. In this patch, we establish all possible cpuid <-> apicid mapping when registering local apic. Signed-off-by: Gu Zheng Signed-off-by: Tang Chen --- arch/x86/include/asm/mpspec.h | 1 + arch/x86/kernel/acpi/boot.c | 6 ++---- arch/x86/kernel/apic/apic.c | 47 ++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 47 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h index b07233b..db902d8 100644 --- a/arch/x86/include/asm/mpspec.h +++ b/arch/x86/include/asm/mpspec.h @@ -86,6 +86,7 @@ static inline void early_reserve_e820_mpc_new(void) { } #endif int generic_processor_info(int apicid, int version); +int __generic_processor_info(int apicid, int version, bool enabled); #define PHYSID_ARRAY_SIZE BITS_TO_LONGS(MAX_LOCAL_APIC) diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index e49ee24..bcc85b2 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -174,15 +174,13 @@ static int acpi_register_lapic(int id, u8 enabled) return -EINVAL; } - if (!enabled) { + if (!enabled) ++disabled_cpus; - return -EINVAL; - } if (boot_cpu_physical_apicid != -1U) ver = apic_version[boot_cpu_physical_apicid]; - return generic_processor_info(id, ver); + return __generic_processor_info(id, ver, enabled); } static int __init diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index a9c9830..c744ffb 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1977,7 +1977,38 @@ void disconnect_bsp_APIC(int virt_wire_setup) apic_write(APIC_LVT1, value); } -static int __generic_processor_info(int apicid, int version, bool enabled) +/* + * Logic cpu number(cpuid) to local APIC id persistent mappings. + * Do not clear the mapping even if cpu is hot-removed. + */ +static int apicid_to_cpuid[] = { + [0 ... NR_CPUS - 1] = -1, +}; + +/* + * Internal cpu id bits, set the bit once cpu present, and never clear it. + */ +static cpumask_t cpuid_mask = CPU_MASK_NONE; + +static int get_cpuid(int apicid) +{ + int free_id, i; + + free_id = cpumask_next_zero(-1, &cpuid_mask); + if (free_id >= nr_cpu_ids) + return -1; + + for (i = 0; i < free_id; i++) + if (apicid_to_cpuid[i] == apicid) + return i; + + apicid_to_cpuid[free_id] = apicid; + cpumask_set_cpu(free_id, &cpuid_mask); + + return free_id; +} + +int __generic_processor_info(int apicid, int version, bool enabled) { int cpu, max = nr_cpu_ids; bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid, @@ -2058,8 +2089,18 @@ static int __generic_processor_info(int apicid, int version, bool enabled) * for BSP. */ cpu = 0; - } else - cpu = cpumask_next_zero(-1, cpu_present_mask); + } else { + cpu = get_cpuid(apicid); + if (cpu < 0) { + int thiscpu = max + disabled_cpus; + + pr_warning(" Processor %d/0x%x ignored.\n", + thiscpu, apicid); + if (enabled) + disabled_cpus++; + return -EINVAL; + } + } /* * Validate version -- 1.9.3 -- 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/