diff options
Diffstat (limited to 'arch/x86_64/kernel/smpboot.c')
-rw-r--r-- | arch/x86_64/kernel/smpboot.c | 120 |
1 files changed, 93 insertions, 27 deletions
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c index e12d7baeb33..683c33f7b96 100644 --- a/arch/x86_64/kernel/smpboot.c +++ b/arch/x86_64/kernel/smpboot.c @@ -64,9 +64,8 @@ int smp_num_siblings = 1; /* Package ID of each logical CPU */ u8 phys_proc_id[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID }; +/* core ID of each logical CPU */ u8 cpu_core_id[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID }; -EXPORT_SYMBOL(phys_proc_id); -EXPORT_SYMBOL(cpu_core_id); /* Bitmask of currently online CPUs */ cpumask_t cpu_online_map __read_mostly; @@ -89,7 +88,10 @@ struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned; /* Set when the idlers are all forked */ int smp_threads_ready; +/* representing HT siblings of each logical CPU */ cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly; + +/* representing HT and core siblings of each logical CPU */ cpumask_t cpu_core_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_core_map); @@ -436,30 +438,59 @@ void __cpuinit smp_callin(void) cpu_set(cpuid, cpu_callin_map); } +/* representing cpus for which sibling maps can be computed */ +static cpumask_t cpu_sibling_setup_map; + static inline void set_cpu_sibling_map(int cpu) { int i; + struct cpuinfo_x86 *c = cpu_data; + + cpu_set(cpu, cpu_sibling_setup_map); if (smp_num_siblings > 1) { - for_each_cpu(i) { - if (cpu_core_id[cpu] == cpu_core_id[i]) { + for_each_cpu_mask(i, cpu_sibling_setup_map) { + if (phys_proc_id[cpu] == phys_proc_id[i] && + cpu_core_id[cpu] == cpu_core_id[i]) { cpu_set(i, cpu_sibling_map[cpu]); cpu_set(cpu, cpu_sibling_map[i]); + cpu_set(i, cpu_core_map[cpu]); + cpu_set(cpu, cpu_core_map[i]); } } } else { cpu_set(cpu, cpu_sibling_map[cpu]); } - if (current_cpu_data.x86_num_cores > 1) { - for_each_cpu(i) { - if (phys_proc_id[cpu] == phys_proc_id[i]) { - cpu_set(i, cpu_core_map[cpu]); - cpu_set(cpu, cpu_core_map[i]); - } - } - } else { + if (current_cpu_data.x86_max_cores == 1) { cpu_core_map[cpu] = cpu_sibling_map[cpu]; + c[cpu].booted_cores = 1; + return; + } + + for_each_cpu_mask(i, cpu_sibling_setup_map) { + if (phys_proc_id[cpu] == phys_proc_id[i]) { + cpu_set(i, cpu_core_map[cpu]); + cpu_set(cpu, cpu_core_map[i]); + /* + * Does this new cpu bringup a new core? + */ + if (cpus_weight(cpu_sibling_map[cpu]) == 1) { + /* + * for each core in package, increment + * the booted_cores for this new cpu + */ + if (first_cpu(cpu_sibling_map[i]) == i) + c[cpu].booted_cores++; + /* + * increment the core count for all + * the other cpus in this package + */ + if (i != cpu) + c[i].booted_cores++; + } else if (i != cpu && !c[cpu].booted_cores) + c[cpu].booted_cores = c[i].booted_cores; + } } } @@ -474,6 +505,7 @@ void __cpuinit start_secondary(void) * things done here to the most necessary things. */ cpu_init(); + preempt_disable(); smp_callin(); /* otherwise gcc will move up the smp_processor_id before the cpu_init */ @@ -880,6 +912,9 @@ static __init void disable_smp(void) } #ifdef CONFIG_HOTPLUG_CPU + +int additional_cpus __initdata = -1; + /* * cpu_possible_map should be static, it cannot change as cpu's * are onlined, or offlined. The reason is per-cpu data-structures @@ -888,14 +923,38 @@ static __init void disable_smp(void) * cpu_present_map on the other hand can change dynamically. * In case when cpu_hotplug is not compiled, then we resort to current * behaviour, which is cpu_possible == cpu_present. - * If cpu-hotplug is supported, then we need to preallocate for all - * those NR_CPUS, hence cpu_possible_map represents entire NR_CPUS range. * - Ashok Raj + * + * Three ways to find out the number of additional hotplug CPUs: + * - If the BIOS specified disabled CPUs in ACPI/mptables use that. + * - otherwise use half of the available CPUs or 2, whatever is more. + * - The user can overwrite it with additional_cpus=NUM + * We do this because additional CPUs waste a lot of memory. + * -AK */ -static void prefill_possible_map(void) +__init void prefill_possible_map(void) { int i; - for (i = 0; i < NR_CPUS; i++) + int possible; + + if (additional_cpus == -1) { + if (disabled_cpus > 0) { + additional_cpus = disabled_cpus; + } else { + additional_cpus = num_processors / 2; + if (additional_cpus == 0) + additional_cpus = 2; + } + } + possible = num_processors + additional_cpus; + if (possible > NR_CPUS) + possible = NR_CPUS; + + printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n", + possible, + max_t(int, possible - num_processors, 0)); + + for (i = 0; i < possible; i++) cpu_set(i, cpu_possible_map); } #endif @@ -966,10 +1025,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus) nmi_watchdog_default(); current_cpu_data = boot_cpu_data; current_thread_info()->cpu = 0; /* needed? */ - -#ifdef CONFIG_HOTPLUG_CPU - prefill_possible_map(); -#endif + set_cpu_sibling_map(0); if (smp_sanity_check(max_cpus) < 0) { printk(KERN_INFO "SMP disabled\n"); @@ -1013,8 +1069,6 @@ void __init smp_prepare_boot_cpu(void) int me = smp_processor_id(); cpu_set(me, cpu_online_map); cpu_set(me, cpu_callout_map); - cpu_set(0, cpu_sibling_map[0]); - cpu_set(0, cpu_core_map[0]); per_cpu(cpu_state, me) = CPU_ONLINE; } @@ -1067,9 +1121,6 @@ int __cpuinit __cpu_up(unsigned int cpu) */ void __init smp_cpus_done(unsigned int max_cpus) { -#ifndef CONFIG_HOTPLUG_CPU - zap_low_mappings(); -#endif smp_cleanup_boot(); #ifdef CONFIG_X86_IO_APIC @@ -1086,15 +1137,24 @@ void __init smp_cpus_done(unsigned int max_cpus) static void remove_siblinginfo(int cpu) { int sibling; + struct cpuinfo_x86 *c = cpu_data; + for_each_cpu_mask(sibling, cpu_core_map[cpu]) { + cpu_clear(cpu, cpu_core_map[sibling]); + /* + * last thread sibling in this cpu core going down + */ + if (cpus_weight(cpu_sibling_map[cpu]) == 1) + c[sibling].booted_cores--; + } + for_each_cpu_mask(sibling, cpu_sibling_map[cpu]) cpu_clear(cpu, cpu_sibling_map[sibling]); - for_each_cpu_mask(sibling, cpu_core_map[cpu]) - cpu_clear(cpu, cpu_core_map[sibling]); cpus_clear(cpu_sibling_map[cpu]); cpus_clear(cpu_core_map[cpu]); phys_proc_id[cpu] = BAD_APICID; cpu_core_id[cpu] = BAD_APICID; + cpu_clear(cpu, cpu_sibling_setup_map); } void remove_cpu_from_maps(void) @@ -1158,6 +1218,12 @@ void __cpu_die(unsigned int cpu) printk(KERN_ERR "CPU %u didn't die...\n", cpu); } +static __init int setup_additional_cpus(char *s) +{ + return get_option(&s, &additional_cpus); +} +__setup("additional_cpus=", setup_additional_cpus); + #else /* ... !CONFIG_HOTPLUG_CPU */ int __cpu_disable(void) |