/* * arch/s390/kernel/smp.c * * Copyright IBM Corp. 1999, 2009 * 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) * * based on other smp stuff by * (c) 1995 Alan Cox, CymruNET Ltd * (c) 1998 Ingo Molnar * * We work with logical cpu numbering everywhere we can. The only * functions using the real cpu address (got from STAP) are the sigp * functions. For all other functions we use the identity mapping. * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is * used e.g. to find the idle task belonging to a logical cpu. Every array * in the kernel is sorted by the logical cpu number and not by the physical * one which is causing all the confusion with __cpu_logical_map and * cpu_number_map in other architectures. */ #define KMSG_COMPONENT "cpu" #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "entry.h" static struct task_struct *current_set[NR_CPUS]; static u8 smp_cpu_type; static int smp_use_sigp_detection; enum s390_cpu_state { CPU_STATE_STANDBY, CPU_STATE_CONFIGURED, }; DEFINE_MUTEX(smp_cpu_state_mutex); int smp_cpu_polarization[NR_CPUS]; static int smp_cpu_state[NR_CPUS]; static int cpu_management; static DEFINE_PER_CPU(struct cpu, cpu_devices); static void smp_ext_bitcall(int, ec_bit_sig); void smp_send_stop(void) { int cpu, rc; /* Disable all interrupts/machine checks */ __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); trace_hardirqs_off(); /* stop all processors */ for_each_online_cpu(cpu) { if (cpu == smp_processor_id()) continue; do { rc = signal_processor(cpu, sigp_stop); } while (rc == sigp_busy); while (!smp_cpu_not_running(cpu)) cpu_relax(); } } /* * This is the main routine where commands issued by other * cpus are handled. */ static void do_ext_call_interrupt(__u16 code) { unsigned long bits; /* * handle bit signal external calls * * For the ec_schedule signal we have to do nothing. All the work * is done automatically when we return from the interrupt. */ bits = xchg(&S390_lowcore.ext_call_fast, 0); if (test_bit(ec_call_function, &bits)) generic_smp_call_function_interrupt(); if (test_bit(ec_call_function_single, &bits)) generic_smp_call_function_single_interrupt(); } /* * Send an external call sigp to another cpu and return without waiting * for its completion. */ static void smp_ext_bitcall(int cpu, ec_bit_sig sig) { /* * Set signaling bit in lowcore of target cpu and kick it */ set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); while (signal_processor(cpu, sigp_emergency_signal) == sigp_busy) udelay(10); } void arch_send_call_function_ipi(cpumask_t mask) { int cpu; for_each_cpu_mask(cpu, mask) smp_ext_bitcall(cpu, ec_call_function); } void arch_send_call_function_single_ipi(int cpu) { smp_ext_bitcall(cpu, ec_call_function_single); } #ifndef CONFIG_64BIT /* * this function sends a 'purge tlb' signal to another CPU. */ static void smp_ptlb_callback(void *info) { __tlb_flush_local(); } void smp_ptlb_all(void) { on_each_cpu(smp_ptlb_callback, NULL, 1); } EXPORT_SYMBOL(smp_ptlb_all); #endif /* ! CONFIG_64BIT */ /* * this function sends a 'reschedule' IPI to another CPU. * it goes straight through and wastes no time serializing * anything. Worst case is that we lose a reschedule ... */ void smp_send_reschedule(int cpu) { smp_ext_bitcall(cpu, ec_schedule); } /* * parameter area for the set/clear control bit callbacks */ struct ec_creg_mask_parms { unsigned long orvals[16]; unsigned long andvals[16]; }; /* * callback for setting/clearing control bits */ static void smp_ctl_bit_callback(void *info) { struct ec_creg_mask_parms *pp = info; unsigned long cregs[16]; int i; __ctl_store(cregs, 0, 15); for (i = 0; i <= 15; i++) cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; __ctl_load(cregs, 0, 15); } /* * Set a bit in a control register of all cpus */ void smp_ctl_set_bit(int cr, int bit) { struct ec_creg_mask_parms parms; memset(&parms.orvals, 0, sizeof(parms.orvals)); memset(&parms.andvals, 0xff, sizeof(parms.andvals)); parms.orvals[cr] = 1 << bit; on_each_cpu(smp_ctl_bit_callback, &parms, 1); } EXPORT_SYMBOL(smp_ctl_set_bit); /* * Clear a bit in a control register of all cpus */ void smp_ctl_clear_bit(int cr, int bit) { struct ec_creg_mask_parms parms; memset(&parms.orvals, 0, sizeof(parms.orvals)); memset(&parms.andvals, 0xff, sizeof(parms.andvals)); parms.andvals[cr] = ~(1L << bit); on_each_cpu(smp_ctl_bit_callback, &parms, 1); } EXPORT_SYMBOL(smp_ctl_clear_bit); /* * In early ipl state a temp. logically cpu number is needed, so the sigp * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1. */ #define CPU_INIT_NO 1 #ifdef CONFIG_ZFCPDUMP /* * zfcpdump_prefix_array holds prefix registers for the following scenario: * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to * save its prefix registers, since they get lost, when switching from 31 bit * to 64 bit. */ unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \ __attribute__((__section__(".data"))); static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { if (ipl_info.type != IPL_TYPE_FCP_DUMP) return; if (cpu >= NR_CPUS) { pr_warning("CPU %i exceeds the maximum %i and is excluded from " "the dump\n", cpu, NR_CPUS - 1); return; } zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL); __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu; while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) == sigp_busy) cpu_relax(); memcpy(zfcpdump_save_areas[cpu], (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE, SAVE_AREA_SIZE); #ifdef CONFIG_64BIT /* copy original prefix register */ zfcpdump_save_areas[cpu]->s390x.pref_reg = zfcpdump_prefix_array[cpu]; #endif } union save_area *zfcpdump_save_areas[NR_CPUS + 1]; EXPORT_SYMBOL_GPL(zfcpdump_save_areas); #else static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { } #endif /* CONFIG_ZFCPDUMP */ static int cpu_stopped(int cpu) { __u32 status; /* Check for stopped state */ if (signal_processor_ps(&status, 0, cpu, sigp_sense) == sigp_status_stored) { if (status & 0x40) return 1; } return 0; } static int cpu_known(int cpu_id) { int cpu; for_each_present_cpu(cpu) { if (__cpu_logical_map[cpu] == cpu_id) return 1; } return 0; } static int smp_rescan_cpus_sigp(cpumask_t avail) { int cpu_id, logical_cpu; logical_cpu = cpumask_first(&avail); if (logical_cpu >= nr_cpu_ids) return 0; for (cpu_id = 0; cpu_id <= MAX_CPU_ADDRESS; cpu_id++) { if (cpu_known(cpu_id)) continue; __cpu_logical_map[logical_cpu] = cpu_id; smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; if (!cpu_stopped(logical_cpu)) continue; cpu_set(logical_cpu, cpu_present_map); smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; logical_cpu = cpumask_next(logical_cpu, &avail); if (logical_cpu >= nr_cpu_ids) break; } return 0; } static int smp_rescan_cpus_sclp(cpumask_t avail) { struct sclp_cpu_info *info; int cpu_id, logical_cpu, cpu; int rc; logical_cpu = cpumask_first(&avail); if (logical_cpu >= nr_cpu_ids) return 0; info = kmalloc(sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM; rc = sclp_get_cpu_info(info); if (rc) goto out; for (cpu = 0; cpu < info->combined; cpu++) { if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) continue; cpu_id = info->cpu[cpu].address; if (cpu_known(cpu_id)) continue; __cpu_logical_map[logical_cpu] = cpu_id; smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; cpu_set(logical_cpu, cpu_present_map); if (cpu >= info->configured) smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY; else smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; logical_cpu = cpumask_next(logical_cpu, &avail); if (logical_cpu >= nr_cpu_ids) break; } out: kfree(info); return rc; } static int __smp_rescan_cpus(void) { cpumask_t avail; cpus_xor(avail, cpu_possible_map, cpu_present_map); if (smp_use_sigp_detection) return smp_rescan_cpus_sigp(avail); else return smp_rescan_cpus_sclp(avail); } static void __init smp_detect_cpus(void) { unsigned int cpu, c_cpus, s_cpus; struct sclp_cpu_info *info; u16 boot_cpu_addr, cpu_addr; c_cpus = 1; s_cpus = 0; boot_cpu_addr = __cpu_logical_map[0]; info = kmalloc(sizeof(*info), GFP_KERNEL); if (!info) panic("smp_detect_cpus failed to allocate memory\n"); /* Use sigp detection algorithm if sclp doesn't work. */ if (sclp_get_cpu_info(info)) { smp_use_sigp_detection = 1; for (cpu = 0; cpu <= MAX_CPU_ADDRESS; cpu++) { if (cpu == boot_cpu_addr) continue; __cpu_logical_map[CPU_INIT_NO] = cpu; if (!cpu_stopped(CPU_INIT_NO)) continue; smp_get_save_area(c_cpus, cpu); c_cpus++; } goto out; } if (info->has_cpu_type) { for (cpu = 0; cpu < info->combined; cpu++) { if (info->cpu[cpu].address == boot_cpu_addr) { smp_cpu_type = info->cpu[cpu].type; break; } } } for (cpu = 0; cpu < info->combined; cpu++) { if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) continue; cpu_addr = info->cpu[cpu].address; if (cpu_addr == boot_cpu_addr) continue; __cpu_logical_map[CPU_INIT_NO] = cpu_addr; if (!cpu_stopped(CPU_INIT_NO)) { s_cpus++; continue; } smp_get_save_area(c_cpus, cpu_addr); c_cpus++; } out: kfree(info); pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus); get_online_cpus(); __smp_rescan_cpus(); put_online_cpus(); } /* * Activate a secondary processor. */ int __cpuinit start_secondary(void *cpuvoid) { /* Setup the cpu */ cpu_init(); preempt_disable(); /* Enable TOD clock interrupts on the secondary cpu. */ init_cpu_timer(); /* Enable cpu timer interrupts on the secondary cpu. */ init_cpu_vtimer(); /* Enable pfault pseudo page faults on this cpu. */ pfault_init(); /* call cpu notifiers */ notify_cpu_starting(smp_processor_id()); /* Mark this cpu as online */ ipi_call_lock(); cpu_set(smp_processor_id(), cpu_online_map); ipi_call_unlock(); /* Switch on interrupts */ local_irq_enable(); /* Print info about this processor */ print_cpu_info(); /* cpu_idle will call schedule for us */ cpu_idle(); return 0; } static void __init smp_create_idle(unsigned int cpu) { struct task_struct *p; /* * don't care about the psw and regs settings since we'll never * reschedule the forked task. */ p = fork_idle(cpu); if (IS_ERR(p)) panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); current_set[cpu] = p; } static int __cpuinit smp_alloc_lowcore(int cpu) { unsigned long async_stack, panic_stack; struct _lowcore *lowcore; int lc_order; lc_order = sizeof(long) == 8 ? 1 : 0; lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order); if (!lowcore) return -ENOMEM; async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); panic_stack = __get_free_page(GFP_KERNEL); if (!panic_stack || !async_stack) goto out; memcpy(lowcore, &S390_lowcore, 512); memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512); lowcore->async_stack = async_stack + ASYNC_SIZE; lowcore->panic_stack = panic_stack + PAGE_SIZE; #ifndef CONFIG_64BIT if (MACHINE_HAS_IEEE) { unsigned long save_area; save_area = get_zeroed_page(GFP_KERNEL); if (!save_area) goto out; lowcore->extended_save_area_addr = (u32) save_area; } #else if (vdso_alloc_per_cpu(cpu, lowcore)) goto out; #endif lowcore_ptr[cpu] = lowcore; return 0; out: free_page(panic_stack); free_pages(async_stack, ASYNC_ORDER); free_pages((unsigned long) lowcore, lc_order); return -ENOMEM; } static void smp_free_lowcore(int cpu) { struct _lowcore *lowcore; int lc_order; lc_order = sizeof(long) == 8 ? 1 : 0; lowcore = lowcore_ptr[cpu]; #ifndef CONFIG_64BIT if (MACHINE_HAS_IEEE) free_page((unsigned long) lowcore->extended_save_area_addr); #else vdso_free_per_cpu(cpu, lowcore); #endif free_page(lowcore->panic_stack - PAGE_SIZE); free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER); free_pages((unsigned long) lowcore, lc_order); lowcore_ptr[cpu] = NULL; } /* Upping and downing of CPUs */ int __cpuinit __cpu_up(unsigned int cpu) { struct task_struct *idle; struct _lowcore *cpu_lowcore; struct stack_frame *sf; sigp_ccode ccode; u32 lowcore; if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED) return -EIO; if (smp_alloc_lowcore(cpu)) return -ENOMEM; do { ccode = signal_processor(cpu, sigp_initial_cpu_reset); if (ccode == sigp_busy) udelay(10); if (ccode == sigp_not_operational) goto err_out; } while (ccode == sigp_busy); lowcore = (u32)(unsigned long)lowcore_ptr[cpu]; while (signal_processor_p(lowcore, cpu, sigp_set_prefix) == sigp_busy) udelay(10); idle = current_set[cpu]; cpu_lowcore = lowcore_ptr[cpu]; cpu_lowcore->kernel_stack = (unsigned long) task_stack_page(idle) + THREAD_SIZE; cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle); sf = (struct stack_frame *) (cpu_lowcore->kernel_stack - sizeof(struct pt_regs) - sizeof(struct stack_frame)); memset(sf, 0, sizeof(struct stack_frame)); sf->gprs[9] = (unsigned long) sf; cpu_lowcore->save_area[15] = (unsigned long) sf; __ctl_store(cpu_lowcore->cregs_save_area, 0, 15); asm volatile( " stam 0,15,0(%0)" : : "a" (&cpu_lowcore->access_regs_save_area) : "memory"); cpu_lowcore->percpu_offset = __per_cpu_offset[cpu]; cpu_lowcore->current_task = (unsigned long) idle; cpu_lowcore->cpu_nr = cpu; cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce; cpu_lowcore->machine_flags = S390_lowcore.machine_flags; cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func; eieio(); while (signal_processor(cpu, sigp_restart) == sigp_busy) udelay(10); while (!cpu_online(cpu)) cpu_relax(); return 0; err_out: smp_free_lowcore(cpu); return -EIO; } static int __init setup_possible_cpus(char *s) { int pcpus, cpu; pcpus = simple_strtoul(s, NULL, 0); init_cpu_possible(cpumask_of(0)); for (cpu = 1; cpu < pcpus && cpu < nr_cpu_ids; cpu++) set_cpu_possible(cpu, true); return 0; } early_param("possible_cpus", setup_possible_cpus); #ifdef CONFIG_HOTPLUG_CPU int __cpu_disable(void) { struct ec_creg_mask_parms cr_parms; int cpu = smp_processor_id(); cpu_clear(cpu, cpu_online_map); /* Disable pfault pseudo page faults on this cpu. */ pfault_fini(); memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals)); memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals)); /* disable all external interrupts */ cr_parms.orvals[0] = 0; cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 | 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4); /* disable all I/O interrupts */ cr_parms.orvals[6] = 0; cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 | 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24); /* disable most machine checks */ cr_parms.orvals[14] = 0; cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24); smp_ctl_bit_callback(&cr_parms); return 0; } void __cpu_die(unsigned int cpu) { /* Wait until target cpu is down */ while (!smp_cpu_not_running(cpu)) cpu_relax(); smp_free_lowcore(cpu); pr_info("Processor %d stopped\n", cpu); } void cpu_die(void) { idle_task_exit(); signal_processor(smp_processor_id(), sigp_stop); BUG(); for (;;); } #endif /* CONFIG_HOTPLUG_CPU */ void __init smp_prepare_cpus(unsigned int max_cpus) { #ifndef CONFIG_64BIT unsigned long save_area = 0; #endif unsigned long async_stack, panic_stack; struct _lowcore *lowcore; unsigned int cpu; int lc_order; smp_detect_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"); print_cpu_info(); /* Reallocate current lowcore, but keep its contents. */ lc_order = sizeof(long) == 8 ? 1 : 0; lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order); panic_stack = __get_free_page(GFP_KERNEL); async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); BUG_ON(!lowcore || !panic_stack || !async_stack); #ifndef CONFIG_64BIT if (MACHINE_HAS_IEEE) save_area = get_zeroed_page(GFP_KERNEL); #endif local_irq_disable(); local_mcck_disable(); lowcore_ptr[smp_processor_id()] = lowcore; *lowcore = S390_lowcore; lowcore->panic_stack = panic_stack + PAGE_SIZE; lowcore->async_stack = async_stack + ASYNC_SIZE; #ifndef CONFIG_64BIT if (MACHINE_HAS_IEEE) lowcore->extended_save_area_addr = (u32) save_area; #endif set_prefix((u32)(unsigned long) lowcore); local_mcck_enable(); local_irq_enable(); #ifdef CONFIG_64BIT if (vdso_alloc_per_cpu(smp_processor_id(), &S390_lowcore)) BUG(); #endif for_each_possible_cpu(cpu) if (cpu != smp_processor_id()) smp_create_idle(cpu); } void __init smp_prepare_boot_cpu(void) { BUG_ON(smp_processor_id() != 0); current_thread_info()->cpu = 0; cpu_set(0, cpu_present_map); cpu_set(0, cpu_online_map); S390_lowcore.percpu_offset = __per_cpu_offset[0]; current_set[0] = current; smp_cpu_state[0] = CPU_STATE_CONFIGURED; smp_cpu_polarization[0] = POLARIZATION_UNKNWN; } void __init smp_cpus_done(unsigned int max_cpus) { } /* * the frequency of the profiling timer can be changed * by writing a multiplier value into /proc/profile. * * usually you want to run this on all CPUs ;) */ int setup_profiling_timer(unsigned int multiplier) { return 0; } #ifdef CONFIG_HOTPLUG_CPU static ssize_t cpu_configure_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { ssize_t count; mutex_lock(&smp_cpu_state_mutex); count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]); mutex_unlock(&smp_cpu_state_mutex); return count; } static ssize_t cpu_configure_store(struct sys_device *dev, struct sysdev_attribute *attr, const char *buf, size_t count) { int cpu = dev->id; int val, rc; char delim; if (sscanf(buf, "%d %c", &val, &delim) != 1) return -EINVAL; if (val != 0 && val != 1) return -EINVAL; get_online_cpus(); mutex_lock(&smp_cpu_state_mutex); rc = -EBUSY; if (cpu_online(cpu)) goto out; rc = 0; switch (val) { case 0: if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) { rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]); if (!rc) { smp_cpu_state[cpu] = CPU_STATE_STANDBY; smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; } } break; case 1: if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) { rc = sclp_cpu_configure(__cpu_logical_map[cpu]); if (!rc) { smp_cpu_state[cpu] = CPU_STATE_CONFIGURED; smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; } } break; default: break; } out: mutex_unlock(&smp_cpu_state_mutex); put_online_cpus(); return rc ? rc : count; } static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); #endif /* CONFIG_HOTPLUG_CPU */ static ssize_t cpu_polarization_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { int cpu = dev->id; ssize_t count; mutex_lock(&smp_cpu_state_mutex); switch (smp_cpu_polarization[cpu]) { case POLARIZATION_HRZ: count = sprintf(buf, "horizontal\n"); break; case POLARIZATION_VL: count = sprintf(buf, "vertical:low\n"); break; case POLARIZATION_VM: count = sprintf(buf, "vertical:medium\n"); break; case POLARIZATION_VH: count = sprintf(buf, "vertical:high\n"); break; default: count = sprintf(buf, "unknown\n"); break; } mutex_unlock(&smp_cpu_state_mutex); return count; } static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL); static ssize_t show_cpu_address(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]); } static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL); static struct attribute *cpu_common_attrs[] = { #ifdef CONFIG_HOTPLUG_CPU &attr_configure.attr, #endif &attr_address.attr, &attr_polarization.attr, NULL, }; static struct attribute_group cpu_common_attr_group = { .attrs = cpu_common_attrs, }; static ssize_t show_capability(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { unsigned int capability; int rc; rc = get_cpu_capability(&capability); if (rc) return rc; return sprintf(buf, "%u\n", capability); } static SYSDEV_ATTR(capability, 0444, show_capability, NULL); static ssize_t show_idle_count(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct s390_idle_data *idle; unsigned long long idle_count; unsigned int sequence; idle = &per_cpu(s390_idle, dev->id); repeat: sequence = idle->sequence; smp_rmb(); if (sequence & 1) goto repeat; idle_count = idle->idle_count; if (idle->idle_enter) idle_count++; smp_rmb(); if (idle->sequence != sequence) goto repeat; return sprintf(buf, "%llu\n", idle_count); } static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL); static ssize_t show_idle_time(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct s390_idle_data *idle; unsigned long long now, idle_time, idle_enter; unsigned int sequence; idle = &per_cpu(s390_idle, dev->id); now = get_clock(); repeat: sequence = idle->sequence; smp_rmb(); if (sequence & 1) goto repeat; idle_time = idle->idle_time; idle_enter = idle->idle_enter; if (idle_enter != 0ULL && idle_enter < now) idle_time += now - idle_enter; smp_rmb(); if (idle->sequence != sequence) goto repeat; return sprintf(buf, "%llu\n", idle_time >> 12); } static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL); static struct attribute *cpu_online_attrs[] = { &attr_capability.attr, &attr_idle_count.attr, &attr_idle_time_us.attr, NULL, }; static struct attribute_group cpu_online_attr_group = { .attrs = cpu_online_attrs, }; static int __cpuinit smp_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned int)(long)hcpu; struct cpu *c = &per_cpu(cpu_devices, cpu); struct sys_device *s = &c->sysdev; struct s390_idle_data *idle; switch (action) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: idle = &per_cpu(s390_idle, cpu); memset(idle, 0, sizeof(struct s390_idle_data)); if (sysfs_create_group(&s->kobj, &cpu_online_attr_group)) return NOTIFY_BAD; break; case CPU_DEAD: case CPU_DEAD_FROZEN: sysfs_remove_group(&s->kobj, &cpu_online_attr_group); break; } return NOTIFY_OK; } static struct notifier_block __cpuinitdata smp_cpu_nb = { .notifier_call = smp_cpu_notify, }; static int __devinit smp_add_present_cpu(int cpu) { struct cpu *c = &per_cpu(cpu_devices, cpu); struct sys_device *s = &c->sysdev; int rc; c->hotpluggable = 1; rc = register_cpu(c, cpu); if (rc) goto out; rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group); if (rc) goto out_cpu; if (!cpu_online(cpu)) goto out; rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group); if (!rc) return 0; sysfs_remove_group(&s->kobj, &cpu_common_attr_group); out_cpu: #ifdef CONFIG_HOTPLUG_CPU unregister_cpu(c); #endif out: return rc; } #ifdef CONFIG_HOTPLUG_CPU int __ref smp_rescan_cpus(void) { cpumask_t newcpus; int cpu; int rc; get_online_cpus(); mutex_lock(&smp_cpu_state_mutex); newcpus = cpu_present_map; rc = __smp_rescan_cpus(); if (rc) goto out; cpus_andnot(newcpus, cpu_present_map, newcpus); for_each_cpu_mask(cpu, newcpus) { rc = smp_add_present_cpu(cpu); if (rc) cpu_clear(cpu, cpu_present_map); } rc = 0; out: mutex_unlock(&smp_cpu_state_mutex); put_online_cpus(); if (!cpus_empty(newcpus)) topology_schedule_update(); return rc; } static ssize_t __ref rescan_store(struct sysdev_class *class, const char *buf, size_t count) { int rc; rc = smp_rescan_cpus(); return rc ? rc : count; } static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store); #endif /* CONFIG_HOTPLUG_CPU */ static ssize_t dispatching_show(struct sysdev_class *class, char *buf) { ssize_t count; mutex_lock(&smp_cpu_state_mutex); count = sprintf(buf, "%d\n", cpu_management); mutex_unlock(&smp_cpu_state_mutex); return count; } static ssize_t dispatching_store(struct sysdev_class *dev, const char *buf, size_t count) { int val, rc; char delim; if (sscanf(buf, "%d %c", &val, &delim) != 1) return -EINVAL; if (val != 0 && val != 1) return -EINVAL; rc = 0; get_online_cpus(); mutex_lock(&smp_cpu_state_mutex); if (cpu_management == val) goto out; rc = topology_set_cpu_management(val); if (!rc) cpu_management = val; out: mutex_unlock(&smp_cpu_state_mutex); put_online_cpus(); return rc ? rc : count; } static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show, dispatching_store); /* * If the resume kernel runs on another cpu than the suspended kernel, * we have to switch the cpu IDs in the logical map. */ void smp_switch_boot_cpu_in_resume(u32 resume_phys_cpu_id, struct _lowcore *suspend_lowcore) { int cpu, suspend_cpu_id, resume_cpu_id; u32 suspend_phys_cpu_id; suspend_phys_cpu_id = __cpu_logical_map[suspend_lowcore->cpu_nr]; suspend_cpu_id = suspend_lowcore->cpu_nr; for_each_present_cpu(cpu) { if (__cpu_logical_map[cpu] == resume_phys_cpu_id) { resume_cpu_id = cpu; goto found; } } panic("Could not find resume cpu in logical map.\n"); found: printk("Resume cpu ID: %i/%i\n", resume_phys_cpu_id, resume_cpu_id); printk("Suspend cpu ID: %i/%i\n", suspend_phys_cpu_id, suspend_cpu_id); __cpu_logical_map[resume_cpu_id] = suspend_phys_cpu_id; __cpu_logical_map[suspend_cpu_id] = resume_phys_cpu_id; lowcore_ptr[suspend_cpu_id]->cpu_addr = resume_phys_cpu_id; } u32 smp_get_phys_cpu_id(void) { return __cpu_logical_map[smp_processor_id()]; } static int __init topology_init(void) { int cpu; int rc; register_cpu_notifier(&smp_cpu_nb); #ifdef CONFIG_HOTPLUG_CPU rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan); if (rc) return rc; #endif rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching); if (rc) return rc; for_each_present_cpu(cpu) { rc = smp_add_present_cpu(cpu); if (rc) return rc; } return 0; } subsys_initcall(topology_init);