From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f69.google.com (mail-it0-f69.google.com [209.85.214.69]) by kanga.kvack.org (Postfix) with ESMTP id 543B46B0260 for ; Tue, 19 Jul 2016 03:31:36 -0400 (EDT) Received: by mail-it0-f69.google.com with SMTP id u186so26920830ita.0 for ; Tue, 19 Jul 2016 00:31:36 -0700 (PDT) Received: from heian.cn.fujitsu.com ([59.151.112.132]) by mx.google.com with ESMTP id b72si20938348iob.246.2016.07.19.00.31.34 for ; Tue, 19 Jul 2016 00:31:35 -0700 (PDT) From: Dou Liyang Subject: [PATCH v8 3/7] x86, acpi, cpu-hotplug: Introduce cpuid_to_apicid[] array to store persistent cpuid <-> apicid mapping. Date: Tue, 19 Jul 2016 15:28:04 +0800 Message-ID: <1468913288-16605-4-git-send-email-douly.fnst@cn.fujitsu.com> In-Reply-To: <1468913288-16605-1-git-send-email-douly.fnst@cn.fujitsu.com> References: <1468913288-16605-1-git-send-email-douly.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: cl@linux.com, tj@kernel.org, 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, len.brown@intel.com, lenb@kernel.org, tglx@linutronix.de, chen.tang@easystack.cn, rafael@kernel.org Cc: x86@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Gu Zheng , Tang Chen , Zhu Guihua , Dou Liyang From: Gu Zheng The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that, when node online/offline happens, cache based on cpuid <-> nodeid mapping such as wq_numa_possible_cpumask will not cause any problem. It contains 4 steps: 1. Enable apic registeration flow to handle both enabled and disabled cpus. 2. Introduce a new array storing all possible cpuid <-> apicid mapping. 3. Enable _MAT and MADT relative apis to return non-presnet or disabled cpus' apicid. 4. Establish all possible cpuid <-> nodeid mapping. This patch finishes step 2. In this patch, we introduce a new static array named cpuid_to_apicid[], 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 cpuid_to_apicid[], 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 Signed-off-by: Zhu Guihua Signed-off-by: Dou Liyang --- arch/x86/include/asm/mpspec.h | 1 + arch/x86/kernel/acpi/boot.c | 6 ++--- arch/x86/kernel/apic/apic.c | 61 ++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 61 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 9414f84..37248c3 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 8e3c377..366fbbc 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1998,7 +1998,53 @@ void disconnect_bsp_APIC(int virt_wire_setup) apic_write(APIC_LVT1, value); } -static int __generic_processor_info(int apicid, int version, bool enabled) +/* + * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated + * contiguously, it equals to current allocated max logical CPU ID plus 1. + * All allocated CPU ID should be in [0, nr_logical_cpuidi), so the maximum of + * nr_logical_cpuids is nr_cpu_ids. + * + * NOTE: Reserve 0 for BSP. + */ +static int nr_logical_cpuids = 1; + +/* + * Used to store mapping between logical CPU IDs and APIC IDs. + */ +static int cpuid_to_apicid[] = { + [0 ... NR_CPUS - 1] = -1, +}; + +/* + * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids + * and cpuid_to_apicid[] synchronized. + */ +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 < nr_logical_cpuids; i++) { + if (cpuid_to_apicid[i] == apicid) + return i; + } + + /* Allocate a new cpuid. */ + if (nr_logical_cpuids >= nr_cpu_ids) { + WARN_ONCE(1, "Only %d processors supported." + "Processor %d/0x%x and the rest are ignored.\n", + nr_cpu_ids - 1, nr_logical_cpuids, apicid); + return -1; + } + + cpuid_to_apicid[nr_logical_cpuids] = apicid; + return nr_logical_cpuids++; +} + +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, @@ -2079,8 +2125,17 @@ 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; + } + } /* * This can happen on physical hotplug. The sanity check at boot time -- 2.5.5 -- 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