diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index e052780..4d3355d 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt @@ -11,6 +11,8 @@ Joel Schopp ia64/x86_64: Ashok Raj + s390: + Heiko Carstens Authors: Ashok Raj Lots of feedback: Nathan Lynch , @@ -44,11 +46,9 @@ maxcpus=n Restrict boot time cpus to n. Say if you have 4 cpus, using maxcpus=2 will only boot 2. You can choose to bring the other cpus later online, read FAQ's for more info. -additional_cpus*=n Use this to limit hotpluggable cpus. This option sets - cpu_possible_map = cpu_present_map + additional_cpus - -(*) Option valid only for following architectures -- x86_64, ia64 +additional_cpus=n [x86_64, s390 only] use this to limit hotpluggable cpus. + This option sets + cpu_possible_map = cpu_present_map + additional_cpus ia64 and x86_64 use the number of disabled local apics in ACPI tables MADT to determine the number of potentially hot-pluggable cpus. The implementation diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index de87842..24f62f1 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -600,6 +600,7 @@ setup_arch(char **cmdline_p) init_mm.brk = (unsigned long) &_end; parse_cmdline_early(cmdline_p); + parse_early_param(); setup_memory(); setup_resources(); @@ -607,6 +608,7 @@ setup_arch(char **cmdline_p) cpu_init(); __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr; + smp_setup_cpu_possible_map(); /* * Create kernel page tables and switch to virtual addressing. diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 0d1ad5d..53291e9 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -1,8 +1,7 @@ /* * arch/s390/kernel/smp.c * - * S390 version - * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Copyright (C) IBM Corp. 1999,2006 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), * Martin Schwidefsky (schwidefsky@de.ibm.com) * Heiko Carstens (heiko.carstens@de.ibm.com) @@ -41,8 +40,6 @@ #include #include -/* prototypes */ - extern volatile int __cpu_logical_map[]; /* @@ -51,13 +48,11 @@ extern volatile int __cpu_logical_map[]; struct _lowcore *lowcore_ptr[NR_CPUS]; -cpumask_t cpu_online_map; -cpumask_t cpu_possible_map = CPU_MASK_ALL; +cpumask_t cpu_online_map = CPU_MASK_NONE; +cpumask_t cpu_possible_map = CPU_MASK_NONE; static struct task_struct *current_set[NR_CPUS]; -EXPORT_SYMBOL(cpu_online_map); - /* * Reboot, halt and power_off routines for SMP. */ @@ -490,10 +485,10 @@ void smp_ctl_clear_bit(int cr, int bit) { * Lets check how many CPUs we have. */ -void -__init smp_check_cpus(unsigned int max_cpus) +static unsigned int +__init smp_count_cpus(void) { - int cpu, num_cpus; + unsigned int cpu, num_cpus; __u16 boot_cpu_addr; /* @@ -503,19 +498,20 @@ __init smp_check_cpus(unsigned int max_cpus) boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr; current_thread_info()->cpu = 0; num_cpus = 1; - for (cpu = 0; cpu <= 65535 && num_cpus < max_cpus; cpu++) { + for (cpu = 0; cpu <= 65535; cpu++) { if ((__u16) cpu == boot_cpu_addr) continue; - __cpu_logical_map[num_cpus] = (__u16) cpu; - if (signal_processor(num_cpus, sigp_sense) == + __cpu_logical_map[1] = (__u16) cpu; + if (signal_processor(1, sigp_sense) == sigp_not_operational) continue; - cpu_set(num_cpus, cpu_present_map); num_cpus++; } printk("Detected %d CPU's\n",(int) num_cpus); printk("Boot cpu address %2X\n", boot_cpu_addr); + + return num_cpus; } /* @@ -676,6 +672,32 @@ __cpu_up(unsigned int cpu) return 0; } +static unsigned int __initdata additional_cpus; + +void __init smp_setup_cpu_possible_map(void) +{ + unsigned int pcpus, cpu; + + pcpus = smp_count_cpus() + additional_cpus; + + if (pcpus > NR_CPUS) + pcpus = NR_CPUS; + + for (cpu = 0; cpu < pcpus; cpu++) + cpu_set(cpu, cpu_possible_map); + + cpu_present_map = cpu_possible_map; +} + +#ifdef CONFIG_HOTPLUG_CPU + +static int __init setup_additional_cpus(char *s) +{ + additional_cpus = simple_strtoul(s, NULL, 0); + return 0; +} +early_param("additional_cpus", setup_additional_cpus); + int __cpu_disable(void) { @@ -744,6 +766,8 @@ cpu_die(void) for(;;); } +#endif /* CONFIG_HOTPLUG_CPU */ + /* * Cycle through the processors and setup structures. */ @@ -757,7 +781,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus) /* request the 0x1201 emergency signal external interrupt */ if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0) panic("Couldn't request external interrupt 0x1201"); - smp_check_cpus(max_cpus); memset(lowcore_ptr,0,sizeof(lowcore_ptr)); /* * Initialize prefix pages and stacks for all possible cpus @@ -806,14 +829,12 @@ void __devinit smp_prepare_boot_cpu(void) BUG_ON(smp_processor_id() != 0); cpu_set(0, cpu_online_map); - cpu_set(0, cpu_present_map); S390_lowcore.percpu_offset = __per_cpu_offset[0]; current_set[0] = current; } void smp_cpus_done(unsigned int max_cpus) { - cpu_present_map = cpu_possible_map; } /* @@ -845,6 +866,7 @@ static int __init topology_init(void) subsys_initcall(topology_init); +EXPORT_SYMBOL(cpu_online_map); EXPORT_SYMBOL(cpu_possible_map); EXPORT_SYMBOL(lowcore_ptr); EXPORT_SYMBOL(smp_ctl_set_bit); diff --git a/include/asm-s390/smp.h b/include/asm-s390/smp.h index 9c6e9c3..444dae5 100644 --- a/include/asm-s390/smp.h +++ b/include/asm-s390/smp.h @@ -31,6 +31,7 @@ typedef struct __u16 cpu; } sigp_info; +extern void smp_setup_cpu_possible_map(void); extern int smp_call_function_on(void (*func) (void *info), void *info, int nonatomic, int wait, int cpu); #define NO_PROC_ID 0xFF /* No processor magic marker */ @@ -104,6 +105,7 @@ smp_call_function_on(void (*func) (void *info), void *info, #define smp_cpu_not_running(cpu) 1 #define smp_get_cpu(cpu) ({ 0; }) #define smp_put_cpu(cpu) ({ 0; }) +#define smp_setup_cpu_possible_map() #endif #endif