From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f53.google.com (mail-pa0-f53.google.com [209.85.220.53]) by kanga.kvack.org (Postfix) with ESMTP id 428FF6B0038 for ; Thu, 10 Sep 2015 00:34:21 -0400 (EDT) Received: by pacex6 with SMTP id ex6so30868729pac.0 for ; Wed, 09 Sep 2015 21:34:21 -0700 (PDT) Received: from heian.cn.fujitsu.com ([59.151.112.132]) by mx.google.com with ESMTP id yk2si16195258pac.192.2015.09.09.21.29.54 for ; Wed, 09 Sep 2015 21:34:20 -0700 (PDT) From: Tang Chen Subject: [PATCH v2 5/7] x86, acpi, cpu-hotplug: Introduce apicid_to_cpuid[] array to store persistent cpuid <-> apicid mapping. Date: Thu, 10 Sep 2015 12:27:47 +0800 Message-ID: <1441859269-25831-6-git-send-email-tangchen@cn.fujitsu.com> In-Reply-To: <1441859269-25831-1-git-send-email-tangchen@cn.fujitsu.com> References: <1441859269-25831-1-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: tj@kernel.org, jiang.liu@linux.intel.com, mika.j.penttila@gmail.com, mingo@redhat.com, akpm@linux-foundation.org, rjw@rjwysocki.net, hpa@zytor.com, yasu.isimatu@gmail.com, isimatu.yasuaki@jp.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, gongzhaogang@inspur.com, qiaonuohan@cn.fujitsu.com Cc: tangchen@cn.fujitsu.com, x86@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Gu Zheng From: Gu Zheng This patch finishes step2 mentioned in previous patch 4. 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 | 53 ++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 53 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..42b2a9c 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1977,7 +1977,45 @@ void disconnect_bsp_APIC(int virt_wire_setup) apic_write(APIC_LVT1, value); } -static int __generic_processor_info(int apicid, int version, bool enabled) +/* + * Current allocated max logical CPU ID plus 1. + * All allocated CPU ID should be in [0, max_logical_cpuid), + * so the maximum of max_logical_cpuid is nr_cpu_ids. + * + * NOTE: Reserve 0 for BSP. + */ +static int max_logical_cpuid = 1; + +static int cpuid_to_apicid[] = { + [0 ... NR_CPUS - 1] = -1, +}; + +static int allocate_logical_cpuid(int apicid) +{ + int i; + + /* + * cpuid <-> apicid mapping is persistent, so when a cpu is up, + * check if the kernel has allocated a cpuid for it. + */ + for (i = 0; i < max_logical_cpuid; i++) { + if (cpuid_to_apicid[i] == apicid) + return i; + } + + /* Allocate a new cpuid. */ + if (max_logical_cpuid >= nr_cpu_ids) { + WARN_ONCE(1, "Only %d processors supported." + "Processor %d/0x%x and the rest are ignored.\n", + nr_cpu_ids - 1, max_logical_cpuid, apicid); + return -1; + } + + cpuid_to_apicid[max_logical_cpuid] = apicid; + return max_logical_cpuid++; +} + +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 +2096,17 @@ static int __generic_processor_info(int apicid, int version, bool enabled) * for BSP. */ cpu = 0; - } else - cpu = cpumask_next_zero(-1, cpu_present_mask); + + /* Logical cpuid 0 is reserved for BSP. */ + cpuid_to_apicid[0] = apicid; + } else { + cpu = allocate_logical_cpuid(apicid); + if (cpu < 0) { + if (enabled) + disabled_cpus++; + return -EINVAL; + } + } /* * Validate version -- 1.9.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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