diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c index 8b42918b7b58..815e3eeed415 100644 --- a/arch/x86/kernel/cpu/topology.c +++ b/arch/x86/kernel/cpu/topology.c @@ -22,6 +22,18 @@ DECLARE_BITMAP(phys_cpu_present_map, MAX_LOCAL_APIC) __read_mostly; /* Used for CPU number allocation and parallel CPU bringup */ u32 cpuid_to_apicid[] __read_mostly = { [0 ... NR_CPUS - 1] = BAD_APICID, }; +/* + * Keep track of assigned, disabled and rejected CPUs. Present assigned + * with 1 as CPU #0 is reserved for the boot CPU. + */ +static struct { + unsigned int nr_assigned_cpus; + unsigned int nr_disabled_cpus; + unsigned int nr_rejected_cpus; +} topo_info __read_mostly = { + .nr_assigned_cpus = 1, +}; + /* * Processor to be disabled specified by kernel parameter * disable_cpu_apicid=, mostly used for the kdump 2nd kernel to @@ -29,19 +41,6 @@ u32 cpuid_to_apicid[] __read_mostly = { [0 ... NR_CPUS - 1] = BAD_APICID, }; */ static u32 disabled_cpu_apicid __ro_after_init = BAD_APICID; -static unsigned int num_processors; -static unsigned int disabled_cpus; - -/* - * 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 IDs should be in the [0, nr_logical_cpuids) range, - * so the maximum of nr_logical_cpuids is nr_cpu_ids. - * - * NOTE: Reserve 0 for BSP. - */ -static int nr_logical_cpuids = 1; - bool arch_match_cpu_phys_id(int cpu, u64 phys_id) { return phys_id == (u64)cpuid_to_apicid[cpu]; @@ -75,7 +74,7 @@ static int __init smp_init_primary_thread_mask(void) return 0; } - for (cpu = 0; cpu < nr_logical_cpuids; cpu++) + for (cpu = 0; cpu < topo_info.nr_assigned_cpus; cpu++) cpu_mark_primary_thread(cpu, cpuid_to_apicid[cpu]); return 0; } @@ -89,7 +88,7 @@ static int topo_lookup_cpuid(u32 apic_id) int i; /* CPU# to APICID mapping is persistent once it is established */ - for (i = 0; i < nr_logical_cpuids; i++) { + for (i = 0; i < topo_info.nr_assigned_cpus; i++) { if (cpuid_to_apicid[i] == apic_id) return i; } @@ -107,22 +106,21 @@ static int allocate_logical_cpuid(u32 apic_id) if (cpu >= 0) return cpu; - cpuid_to_apicid[nr_logical_cpuids] = apic_id; - return nr_logical_cpuids++; + return topo_info.nr_assigned_cpus++; } -static void cpu_update_apic(int cpu, u32 apicid) +static void cpu_update_apic(unsigned int cpu, u32 apic_id) { #if defined(CONFIG_SMP) || defined(CONFIG_X86_64) - early_per_cpu(x86_cpu_to_apicid, cpu) = apicid; + early_per_cpu(x86_cpu_to_apicid, cpu) = apic_id; #endif + cpuid_to_apicid[cpu] = apic_id; set_cpu_possible(cpu, true); - set_bit(apicid, phys_cpu_present_map); + set_bit(apic_id, phys_cpu_present_map); set_cpu_present(cpu, true); - num_processors++; if (system_state != SYSTEM_BOOTING) - cpu_mark_primary_thread(cpu, apicid); + cpu_mark_primary_thread(cpu, apic_id); } static int generic_processor_info(int apicid) @@ -137,18 +135,18 @@ static int generic_processor_info(int apicid) return 0; if (disabled_cpu_apicid == apicid) { - int thiscpu = num_processors + disabled_cpus; + int thiscpu = topo_info.nr_assigned_cpus + topo_info.nr_disabled_cpus; pr_warn("APIC: Disabling requested cpu. Processor %d/0x%x ignored.\n", thiscpu, apicid); - disabled_cpus++; + topo_info.nr_rejected_cpus++; return -ENODEV; } - if (num_processors >= nr_cpu_ids) { + if (topo_info.nr_assigned_cpus >= nr_cpu_ids) { pr_warn_once("APIC: CPU limit of %d reached. Ignoring further CPUs\n", nr_cpu_ids); - disabled_cpus++; + topo_info.nr_rejected_cpus++; return -ENOSPC; } @@ -178,14 +176,16 @@ static int __initdata setup_possible_cpus = -1; */ __init void prefill_possible_map(void) { + unsigned int num_processors = topo_info.nr_assigned_cpus; + unsigned int disabled_cpus = topo_info.nr_disabled_cpus; int i, possible; i = setup_max_cpus ?: 1; if (setup_possible_cpus == -1) { - possible = num_processors; + possible = topo_info.nr_assigned_cpus; #ifdef CONFIG_HOTPLUG_CPU if (setup_max_cpus) - possible += disabled_cpus; + possible += num_processors; #else if (possible > i) possible = i; @@ -238,7 +238,7 @@ void __init topology_register_apic(u32 apic_id, u32 acpi_id, bool present) } if (!present) { - disabled_cpus++; + topo_info.nr_disabled_cpus++; return; } @@ -295,7 +295,6 @@ void topology_hotunplug_apic(unsigned int cpu) per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID; clear_bit(apic_id, phys_cpu_present_map); set_cpu_present(cpu, false); - num_processors--; } #endif