diff options
Diffstat (limited to 'arch/s390/kernel/smp.c')
| -rw-r--r-- | arch/s390/kernel/smp.c | 1459 |
1 files changed, 832 insertions, 627 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index e13c87b446b..243c7e51260 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -1,422 +1,462 @@ /* - * arch/s390/kernel/smp.c + * SMP related functions * - * S390 version - * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation - * 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) + * Copyright IBM Corp. 1999, 2012 + * Author(s): Denis Joseph Barrow, + * Martin Schwidefsky <schwidefsky@de.ibm.com>, + * Heiko Carstens <heiko.carstens@de.ibm.com>, * - * based on other smp stuff by + * based on other smp stuff by * (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net> * (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. + * The code outside of smp.c uses logical cpu numbers, only smp.c does + * the translation of logical to physical cpu ids. All new code that + * operates on physical cpu numbers needs to go into smp.c. */ +#define KMSG_COMPONENT "cpu" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/workqueue.h> #include <linux/module.h> #include <linux/init.h> - #include <linux/mm.h> +#include <linux/err.h> #include <linux/spinlock.h> #include <linux/kernel_stat.h> -#include <linux/smp_lock.h> - #include <linux/delay.h> -#include <linux/cache.h> #include <linux/interrupt.h> +#include <linux/irqflags.h> #include <linux/cpu.h> - -#include <asm/sigp.h> -#include <asm/pgalloc.h> +#include <linux/slab.h> +#include <linux/crash_dump.h> +#include <asm/asm-offsets.h> +#include <asm/switch_to.h> +#include <asm/facility.h> +#include <asm/ipl.h> +#include <asm/setup.h> #include <asm/irq.h> -#include <asm/s390_ext.h> -#include <asm/cpcmd.h> #include <asm/tlbflush.h> +#include <asm/vtimer.h> +#include <asm/lowcore.h> +#include <asm/sclp.h> +#include <asm/vdso.h> +#include <asm/debug.h> +#include <asm/os_info.h> +#include <asm/sigp.h> +#include "entry.h" -/* prototypes */ - -extern volatile int __cpu_logical_map[]; - -/* - * An array with a pointer the lowcore of every CPU. - */ - -struct _lowcore *lowcore_ptr[NR_CPUS]; +enum { + ec_schedule = 0, + ec_call_function_single, + ec_stop_cpu, +}; -cpumask_t cpu_online_map; -cpumask_t cpu_possible_map; +enum { + CPU_STATE_STANDBY, + CPU_STATE_CONFIGURED, +}; -static struct task_struct *current_set[NR_CPUS]; +struct pcpu { + struct cpu *cpu; + struct _lowcore *lowcore; /* lowcore page(s) for the cpu */ + unsigned long async_stack; /* async stack for the cpu */ + unsigned long panic_stack; /* panic stack for the cpu */ + unsigned long ec_mask; /* bit mask for ec_xxx functions */ + int state; /* physical cpu state */ + int polarization; /* physical polarization */ + u16 address; /* physical cpu address */ +}; -EXPORT_SYMBOL(cpu_online_map); +static u8 boot_cpu_type; +static u16 boot_cpu_address; +static struct pcpu pcpu_devices[NR_CPUS]; /* - * Reboot, halt and power_off routines for SMP. + * The smp_cpu_state_mutex must be held when changing the state or polarization + * member of a pcpu data structure within the pcpu_devices arreay. */ -extern char vmhalt_cmd[]; -extern char vmpoff_cmd[]; - -extern void reipl(unsigned long devno); -extern void reipl_diag(void); - -static void smp_ext_bitcall(int, ec_bit_sig); -static void smp_ext_bitcall_others(ec_bit_sig); +DEFINE_MUTEX(smp_cpu_state_mutex); /* - * Structure and data for smp_call_function(). This is designed to minimise - * static memory requirements. It also looks cleaner. + * Signal processor helper functions. */ -static DEFINE_SPINLOCK(call_lock); - -struct call_data_struct { - void (*func) (void *info); - void *info; - atomic_t started; - atomic_t finished; - int wait; -}; +static inline int __pcpu_sigp_relax(u16 addr, u8 order, u32 parm, u32 *status) +{ + int cc; -static struct call_data_struct * call_data; + while (1) { + cc = __pcpu_sigp(addr, order, parm, NULL); + if (cc != SIGP_CC_BUSY) + return cc; + cpu_relax(); + } +} -/* - * 'Call function' interrupt callback - */ -static void do_call_function(void) +static int pcpu_sigp_retry(struct pcpu *pcpu, u8 order, u32 parm) { - void (*func) (void *info) = call_data->func; - void *info = call_data->info; - int wait = call_data->wait; + int cc, retry; - atomic_inc(&call_data->started); - (*func)(info); - if (wait) - atomic_inc(&call_data->finished); + for (retry = 0; ; retry++) { + cc = __pcpu_sigp(pcpu->address, order, parm, NULL); + if (cc != SIGP_CC_BUSY) + break; + if (retry >= 3) + udelay(10); + } + return cc; } -/* - * this function sends a 'generic call function' IPI to all other CPUs - * in the system. - */ - -int smp_call_function (void (*func) (void *info), void *info, int nonatomic, - int wait) -/* - * [SUMMARY] Run a function on all other CPUs. - * <func> The function to run. This must be fast and non-blocking. - * <info> An arbitrary pointer to pass to the function. - * <nonatomic> currently unused. - * <wait> If true, wait (atomically) until function has completed on other CPUs. - * [RETURNS] 0 on success, else a negative status code. Does not return until - * remote CPUs are nearly ready to execute <<func>> or are or have executed. - * - * You must not call this function with disabled interrupts or from a - * hardware interrupt handler or from a bottom half handler. - */ +static inline int pcpu_stopped(struct pcpu *pcpu) { - struct call_data_struct data; - int cpus = num_online_cpus()-1; + u32 uninitialized_var(status); - if (cpus <= 0) + if (__pcpu_sigp(pcpu->address, SIGP_SENSE, + 0, &status) != SIGP_CC_STATUS_STORED) return 0; + return !!(status & (SIGP_STATUS_CHECK_STOP|SIGP_STATUS_STOPPED)); +} - /* Can deadlock when called with interrupts disabled */ - WARN_ON(irqs_disabled()); - - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); - - spin_lock(&call_lock); - call_data = &data; - /* Send a message to all other CPUs and wait for them to respond */ - smp_ext_bitcall_others(ec_call_function); - - /* Wait for response */ - while (atomic_read(&data.started) != cpus) - cpu_relax(); - - if (wait) - while (atomic_read(&data.finished) != cpus) - cpu_relax(); - spin_unlock(&call_lock); - +static inline int pcpu_running(struct pcpu *pcpu) +{ + if (__pcpu_sigp(pcpu->address, SIGP_SENSE_RUNNING, + 0, NULL) != SIGP_CC_STATUS_STORED) + return 1; + /* Status stored condition code is equivalent to cpu not running. */ return 0; } /* - * Call a function on one CPU - * cpu : the CPU the function should be executed on - * - * You must not call this function with disabled interrupts or from a - * hardware interrupt handler. You may call it from a bottom half. - * - * It is guaranteed that the called function runs on the specified CPU, - * preemption is disabled. + * Find struct pcpu by cpu address. */ -int smp_call_function_on(void (*func) (void *info), void *info, - int nonatomic, int wait, int cpu) +static struct pcpu *pcpu_find_address(const struct cpumask *mask, int address) { - struct call_data_struct data; - int curr_cpu; + int cpu; - if (!cpu_online(cpu)) - return -EINVAL; + for_each_cpu(cpu, mask) + if (pcpu_devices[cpu].address == address) + return pcpu_devices + cpu; + return NULL; +} - /* disable preemption for local function call */ - curr_cpu = get_cpu(); +static void pcpu_ec_call(struct pcpu *pcpu, int ec_bit) +{ + int order; - if (curr_cpu == cpu) { - /* direct call to function */ - func(info); - put_cpu(); - return 0; - } + if (test_and_set_bit(ec_bit, &pcpu->ec_mask)) + return; + order = pcpu_running(pcpu) ? SIGP_EXTERNAL_CALL : SIGP_EMERGENCY_SIGNAL; + pcpu_sigp_retry(pcpu, order, 0); +} - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); +static int pcpu_alloc_lowcore(struct pcpu *pcpu, int cpu) +{ + struct _lowcore *lc; + + if (pcpu != &pcpu_devices[0]) { + pcpu->lowcore = (struct _lowcore *) + __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER); + pcpu->async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); + pcpu->panic_stack = __get_free_page(GFP_KERNEL); + if (!pcpu->lowcore || !pcpu->panic_stack || !pcpu->async_stack) + goto out; + } + lc = pcpu->lowcore; + memcpy(lc, &S390_lowcore, 512); + memset((char *) lc + 512, 0, sizeof(*lc) - 512); + lc->async_stack = pcpu->async_stack + ASYNC_SIZE + - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); + lc->panic_stack = pcpu->panic_stack + PAGE_SIZE + - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); + lc->cpu_nr = cpu; + lc->spinlock_lockval = arch_spin_lockval(cpu); +#ifndef CONFIG_64BIT + if (MACHINE_HAS_IEEE) { + lc->extended_save_area_addr = get_zeroed_page(GFP_KERNEL); + if (!lc->extended_save_area_addr) + goto out; + } +#else + if (vdso_alloc_per_cpu(lc)) + goto out; +#endif + lowcore_ptr[cpu] = lc; + pcpu_sigp_retry(pcpu, SIGP_SET_PREFIX, (u32)(unsigned long) lc); + return 0; +out: + if (pcpu != &pcpu_devices[0]) { + free_page(pcpu->panic_stack); + free_pages(pcpu->async_stack, ASYNC_ORDER); + free_pages((unsigned long) pcpu->lowcore, LC_ORDER); + } + return -ENOMEM; +} - spin_lock_bh(&call_lock); - call_data = &data; - smp_ext_bitcall(cpu, ec_call_function); +#ifdef CONFIG_HOTPLUG_CPU - /* Wait for response */ - while (atomic_read(&data.started) != 1) - cpu_relax(); +static void pcpu_free_lowcore(struct pcpu *pcpu) +{ + pcpu_sigp_retry(pcpu, SIGP_SET_PREFIX, 0); + lowcore_ptr[pcpu - pcpu_devices] = NULL; +#ifndef CONFIG_64BIT + if (MACHINE_HAS_IEEE) { + struct _lowcore *lc = pcpu->lowcore; + + free_page((unsigned long) lc->extended_save_area_addr); + lc->extended_save_area_addr = 0; + } +#else + vdso_free_per_cpu(pcpu->lowcore); +#endif + if (pcpu != &pcpu_devices[0]) { + free_page(pcpu->panic_stack); + free_pages(pcpu->async_stack, ASYNC_ORDER); + free_pages((unsigned long) pcpu->lowcore, LC_ORDER); + } +} - if (wait) - while (atomic_read(&data.finished) != 1) - cpu_relax(); +#endif /* CONFIG_HOTPLUG_CPU */ - spin_unlock_bh(&call_lock); - put_cpu(); - return 0; +static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu) +{ + struct _lowcore *lc = pcpu->lowcore; + + if (MACHINE_HAS_TLB_LC) + cpumask_set_cpu(cpu, &init_mm.context.cpu_attach_mask); + cpumask_set_cpu(cpu, mm_cpumask(&init_mm)); + atomic_inc(&init_mm.context.attach_count); + lc->cpu_nr = cpu; + lc->spinlock_lockval = arch_spin_lockval(cpu); + lc->percpu_offset = __per_cpu_offset[cpu]; + lc->kernel_asce = S390_lowcore.kernel_asce; + lc->machine_flags = S390_lowcore.machine_flags; + lc->ftrace_func = S390_lowcore.ftrace_func; + lc->user_timer = lc->system_timer = lc->steal_timer = 0; + __ctl_store(lc->cregs_save_area, 0, 15); + save_access_regs((unsigned int *) lc->access_regs_save_area); + memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list, + MAX_FACILITY_BIT/8); } -EXPORT_SYMBOL(smp_call_function_on); -static inline void do_send_stop(void) +static void pcpu_attach_task(struct pcpu *pcpu, struct task_struct *tsk) { - int cpu, rc; - - /* 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); - } + struct _lowcore *lc = pcpu->lowcore; + struct thread_info *ti = task_thread_info(tsk); + + lc->kernel_stack = (unsigned long) task_stack_page(tsk) + + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); + lc->thread_info = (unsigned long) task_thread_info(tsk); + lc->current_task = (unsigned long) tsk; + lc->user_timer = ti->user_timer; + lc->system_timer = ti->system_timer; + lc->steal_timer = 0; } -static inline void do_store_status(void) +static void pcpu_start_fn(struct pcpu *pcpu, void (*func)(void *), void *data) { - int cpu, rc; + struct _lowcore *lc = pcpu->lowcore; - /* store status of all processors in their lowcores (real 0) */ - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; - do { - rc = signal_processor_p( - (__u32)(unsigned long) lowcore_ptr[cpu], cpu, - sigp_store_status_at_address); - } while(rc == sigp_busy); - } + lc->restart_stack = lc->kernel_stack; + lc->restart_fn = (unsigned long) func; + lc->restart_data = (unsigned long) data; + lc->restart_source = -1UL; + pcpu_sigp_retry(pcpu, SIGP_RESTART, 0); } /* - * this function sends a 'stop' sigp to all other CPUs in the system. - * it goes straight through. + * Call function via PSW restart on pcpu and stop the current cpu. */ -void smp_send_stop(void) +static void pcpu_delegate(struct pcpu *pcpu, void (*func)(void *), + void *data, unsigned long stack) { - /* write magic number to zero page (absolute 0) */ - lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC; - - /* stop other processors. */ - do_send_stop(); - - /* store status of other processors. */ - do_store_status(); + struct _lowcore *lc = lowcore_ptr[pcpu - pcpu_devices]; + unsigned long source_cpu = stap(); + + __load_psw_mask(PSW_KERNEL_BITS); + if (pcpu->address == source_cpu) + func(data); /* should not return */ + /* Stop target cpu (if func returns this stops the current cpu). */ + pcpu_sigp_retry(pcpu, SIGP_STOP, 0); + /* Restart func on the target cpu and stop the current cpu. */ + mem_assign_absolute(lc->restart_stack, stack); + mem_assign_absolute(lc->restart_fn, (unsigned long) func); + mem_assign_absolute(lc->restart_data, (unsigned long) data); + mem_assign_absolute(lc->restart_source, source_cpu); + asm volatile( + "0: sigp 0,%0,%2 # sigp restart to target cpu\n" + " brc 2,0b # busy, try again\n" + "1: sigp 0,%1,%3 # sigp stop to current cpu\n" + " brc 2,1b # busy, try again\n" + : : "d" (pcpu->address), "d" (source_cpu), + "K" (SIGP_RESTART), "K" (SIGP_STOP) + : "0", "1", "cc"); + for (;;) ; } /* - * Reboot, halt and power_off routines for SMP. + * Call function on an online CPU. */ - -static void do_machine_restart(void * __unused) +void smp_call_online_cpu(void (*func)(void *), void *data) { - int cpu; - static atomic_t cpuid = ATOMIC_INIT(-1); - - if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid)) - signal_processor(smp_processor_id(), sigp_stop); - - /* Wait for all other cpus to enter stopped state */ - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; - while(!smp_cpu_not_running(cpu)) - cpu_relax(); - } - - /* Store status of other cpus. */ - do_store_status(); - - /* - * Finally call reipl. Because we waited for all other - * cpus to enter this function we know that they do - * not hold any s390irq-locks (the cpus have been - * interrupted by an external interrupt and s390irq - * locks are always held disabled). - */ - reipl_diag(); - - if (MACHINE_IS_VM) - cpcmd ("IPL", NULL, 0, NULL); - else - reipl (0x10000 | S390_lowcore.ipl_device); + struct pcpu *pcpu; + + /* Use the current cpu if it is online. */ + pcpu = pcpu_find_address(cpu_online_mask, stap()); + if (!pcpu) + /* Use the first online cpu. */ + pcpu = pcpu_devices + cpumask_first(cpu_online_mask); + pcpu_delegate(pcpu, func, data, (unsigned long) restart_stack); } -void machine_restart_smp(char * __unused) +/* + * Call function on the ipl CPU. + */ +void smp_call_ipl_cpu(void (*func)(void *), void *data) { - on_each_cpu(do_machine_restart, NULL, 0, 0); + pcpu_delegate(&pcpu_devices[0], func, data, + pcpu_devices->panic_stack + PAGE_SIZE); } -static void do_wait_for_stop(void) +int smp_find_processor_id(u16 address) { - unsigned long cr[16]; + int cpu; - __ctl_store(cr, 0, 15); - cr[0] &= ~0xffff; - cr[6] = 0; - __ctl_load(cr, 0, 15); - for (;;) - enabled_wait(); + for_each_present_cpu(cpu) + if (pcpu_devices[cpu].address == address) + return cpu; + return -1; } -static void do_machine_halt(void * __unused) +int smp_vcpu_scheduled(int cpu) { - static atomic_t cpuid = ATOMIC_INIT(-1); + return pcpu_running(pcpu_devices + cpu); +} - if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) { - smp_send_stop(); - if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0) - cpcmd(vmhalt_cmd, NULL, 0, NULL); - signal_processor(smp_processor_id(), - sigp_stop_and_store_status); - } - do_wait_for_stop(); +void smp_yield(void) +{ + if (MACHINE_HAS_DIAG44) + asm volatile("diag 0,0,0x44"); } -void machine_halt_smp(void) +void smp_yield_cpu(int cpu) { - on_each_cpu(do_machine_halt, NULL, 0, 0); + if (MACHINE_HAS_DIAG9C) + asm volatile("diag %0,0,0x9c" + : : "d" (pcpu_devices[cpu].address)); + else if (MACHINE_HAS_DIAG44) + asm volatile("diag 0,0,0x44"); } -static void do_machine_power_off(void * __unused) +/* + * Send cpus emergency shutdown signal. This gives the cpus the + * opportunity to complete outstanding interrupts. + */ +static void smp_emergency_stop(cpumask_t *cpumask) { - static atomic_t cpuid = ATOMIC_INIT(-1); + u64 end; + int cpu; - if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) { - smp_send_stop(); - if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0) - cpcmd(vmpoff_cmd, NULL, 0, NULL); - signal_processor(smp_processor_id(), - sigp_stop_and_store_status); + end = get_tod_clock() + (1000000UL << 12); + for_each_cpu(cpu, cpumask) { + struct pcpu *pcpu = pcpu_devices + cpu; + set_bit(ec_stop_cpu, &pcpu->ec_mask); + while (__pcpu_sigp(pcpu->address, SIGP_EMERGENCY_SIGNAL, + 0, NULL) == SIGP_CC_BUSY && + get_tod_clock() < end) + cpu_relax(); + } + while (get_tod_clock() < end) { + for_each_cpu(cpu, cpumask) + if (pcpu_stopped(pcpu_devices + cpu)) + cpumask_clear_cpu(cpu, cpumask); + if (cpumask_empty(cpumask)) + break; + cpu_relax(); } - do_wait_for_stop(); } -void machine_power_off_smp(void) +/* + * Stop all cpus but the current one. + */ +void smp_send_stop(void) { - on_each_cpu(do_machine_power_off, NULL, 0, 0); + cpumask_t cpumask; + int cpu; + + /* Disable all interrupts/machine checks */ + __load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT); + trace_hardirqs_off(); + + debug_set_critical(); + cpumask_copy(&cpumask, cpu_online_mask); + cpumask_clear_cpu(smp_processor_id(), &cpumask); + + if (oops_in_progress) + smp_emergency_stop(&cpumask); + + /* stop all processors */ + for_each_cpu(cpu, &cpumask) { + struct pcpu *pcpu = pcpu_devices + cpu; + pcpu_sigp_retry(pcpu, SIGP_STOP, 0); + while (!pcpu_stopped(pcpu)) + cpu_relax(); + } } /* * This is the main routine where commands issued by other * cpus are handled. */ - -void do_ext_call_interrupt(struct pt_regs *regs, __u16 code) +static void smp_handle_ext_call(void) { - 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); + unsigned long bits; + + /* handle bit signal external calls */ + bits = xchg(&pcpu_devices[smp_processor_id()].ec_mask, 0); + if (test_bit(ec_stop_cpu, &bits)) + smp_stop_cpu(); + if (test_bit(ec_schedule, &bits)) + scheduler_ipi(); + if (test_bit(ec_call_function_single, &bits)) + generic_smp_call_function_single_interrupt(); +} - if (test_bit(ec_call_function, &bits)) - do_call_function(); +static void do_ext_call_interrupt(struct ext_code ext_code, + unsigned int param32, unsigned long param64) +{ + inc_irq_stat(ext_code.code == 0x1202 ? IRQEXT_EXC : IRQEXT_EMS); + smp_handle_ext_call(); } -/* - * 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) +void arch_send_call_function_ipi_mask(const struct cpumask *mask) { - /* - * 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); + int cpu; + + for_each_cpu(cpu, mask) + pcpu_ec_call(pcpu_devices + cpu, ec_call_function_single); } -/* - * Send an external call sigp to every other cpu in the system and - * return without waiting for its completion. - */ -static void smp_ext_bitcall_others(ec_bit_sig sig) -{ - int cpu; - - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; - /* - * 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_single_ipi(int cpu) +{ + pcpu_ec_call(pcpu_devices + cpu, ec_call_function_single); } -#ifndef CONFIG_ARCH_S390X +#ifndef CONFIG_64BIT /* * this function sends a 'purge tlb' signal to another CPU. */ -void smp_ptlb_callback(void *info) +static void smp_ptlb_callback(void *info) { - local_flush_tlb(); + __tlb_flush_local(); } void smp_ptlb_all(void) { - on_each_cpu(smp_ptlb_callback, NULL, 0, 1); + on_each_cpu(smp_ptlb_callback, NULL, 1); } EXPORT_SYMBOL(smp_ptlb_all); -#endif /* ! CONFIG_ARCH_S390X */ +#endif /* ! CONFIG_64BIT */ /* * this function sends a 'reschedule' IPI to another CPU. @@ -425,398 +465,342 @@ EXPORT_SYMBOL(smp_ptlb_all); */ void smp_send_reschedule(int cpu) { - smp_ext_bitcall(cpu, ec_schedule); + pcpu_ec_call(pcpu_devices + cpu, ec_schedule); } /* * parameter area for the set/clear control bit callbacks */ -typedef struct -{ - __u16 start_ctl; - __u16 end_ctl; - unsigned long orvals[16]; - unsigned long andvals[16]; -} ec_creg_mask_parms; +struct ec_creg_mask_parms { + unsigned long orval; + unsigned long andval; + int cr; +}; /* * callback for setting/clearing control bits */ -void smp_ctl_bit_callback(void *info) { - ec_creg_mask_parms *pp; +static void smp_ctl_bit_callback(void *info) +{ + struct ec_creg_mask_parms *pp = info; unsigned long cregs[16]; - int i; - - pp = (ec_creg_mask_parms *) info; - __ctl_store(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl); - for (i = pp->start_ctl; i <= pp->end_ctl; i++) - cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; - __ctl_load(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl); + + __ctl_store(cregs, 0, 15); + cregs[pp->cr] = (cregs[pp->cr] & pp->andval) | pp->orval; + __ctl_load(cregs, 0, 15); } /* * Set a bit in a control register of all cpus */ -void smp_ctl_set_bit(int cr, int bit) { - ec_creg_mask_parms parms; +void smp_ctl_set_bit(int cr, int bit) +{ + struct ec_creg_mask_parms parms = { 1UL << bit, -1UL, cr }; - parms.start_ctl = cr; - parms.end_ctl = cr; - parms.orvals[cr] = 1 << bit; - parms.andvals[cr] = -1L; - preempt_disable(); - smp_call_function(smp_ctl_bit_callback, &parms, 0, 1); - __ctl_set_bit(cr, bit); - preempt_enable(); + 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) { - ec_creg_mask_parms parms; +void smp_ctl_clear_bit(int cr, int bit) +{ + struct ec_creg_mask_parms parms = { 0, ~(1UL << bit), cr }; - parms.start_ctl = cr; - parms.end_ctl = cr; - parms.orvals[cr] = 0; - parms.andvals[cr] = ~(1L << bit); - preempt_disable(); - smp_call_function(smp_ctl_bit_callback, &parms, 0, 1); - __ctl_clear_bit(cr, bit); - preempt_enable(); + on_each_cpu(smp_ctl_bit_callback, &parms, 1); } +EXPORT_SYMBOL(smp_ctl_clear_bit); -/* - * Lets check how many CPUs we have. - */ +#ifdef CONFIG_CRASH_DUMP -void -__init smp_check_cpus(unsigned int max_cpus) +static void __init smp_get_save_area(int cpu, u16 address) { - int cpu, num_cpus; - __u16 boot_cpu_addr; - - /* - * cpu 0 is the boot cpu. See smp_prepare_boot_cpu. - */ - - 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++) { - if ((__u16) cpu == boot_cpu_addr) - continue; - __cpu_logical_map[num_cpus] = (__u16) cpu; - if (signal_processor(num_cpus, sigp_sense) == - sigp_not_operational) - continue; - cpu_set(num_cpus, cpu_present_map); - num_cpus++; + void *lc = pcpu_devices[0].lowcore; + struct save_area *save_area; + + if (is_kdump_kernel()) + return; + if (!OLDMEM_BASE && (address == boot_cpu_address || + ipl_info.type != IPL_TYPE_FCP_DUMP)) + return; + save_area = dump_save_area_create(cpu); + if (!save_area) + panic("could not allocate memory for save area\n"); + if (address == boot_cpu_address) { + /* Copy the registers of the boot cpu. */ + copy_oldmem_page(1, (void *) save_area, sizeof(*save_area), + SAVE_AREA_BASE - PAGE_SIZE, 0); + return; } - - for (cpu = 1; cpu < max_cpus; cpu++) - cpu_set(cpu, cpu_possible_map); - - printk("Detected %d CPU's\n",(int) num_cpus); - printk("Boot cpu address %2X\n", boot_cpu_addr); + /* Get the registers of a non-boot cpu. */ + __pcpu_sigp_relax(address, SIGP_STOP_AND_STORE_STATUS, 0, NULL); + memcpy_real(save_area, lc + SAVE_AREA_BASE, sizeof(*save_area)); } -/* - * Activate a secondary processor. - */ -extern void init_cpu_timer(void); -extern void init_cpu_vtimer(void); -extern int pfault_init(void); -extern void pfault_fini(void); - -int __devinit start_secondary(void *cpuvoid) -{ - /* Setup the cpu */ - cpu_init(); - /* init per CPU timer */ - init_cpu_timer(); -#ifdef CONFIG_VIRT_TIMER - init_cpu_vtimer(); -#endif -#ifdef CONFIG_PFAULT - /* Enable pfault pseudo page faults on this cpu. */ - if (MACHINE_IS_VM) - pfault_init(); -#endif - /* Mark this cpu as online */ - cpu_set(smp_processor_id(), cpu_online_map); - /* Switch on interrupts */ - local_irq_enable(); - /* Print info about this processor */ - print_cpu_info(&S390_lowcore.cpu_data); - /* cpu_idle will call schedule for us */ - cpu_idle(); - return 0; -} - -static void __init smp_create_idle(unsigned int cpu) +int smp_store_status(int cpu) { - struct task_struct *p; + struct pcpu *pcpu; - /* - * 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; + pcpu = pcpu_devices + cpu; + if (__pcpu_sigp_relax(pcpu->address, SIGP_STOP_AND_STORE_STATUS, + 0, NULL) != SIGP_CC_ORDER_CODE_ACCEPTED) + return -EIO; + return 0; } -/* Reserving and releasing of CPUs */ +#else /* CONFIG_CRASH_DUMP */ -static DEFINE_SPINLOCK(smp_reserve_lock); -static int smp_cpu_reserved[NR_CPUS]; +static inline void smp_get_save_area(int cpu, u16 address) { } -int -smp_get_cpu(cpumask_t cpu_mask) -{ - unsigned long flags; - int cpu; +#endif /* CONFIG_CRASH_DUMP */ - spin_lock_irqsave(&smp_reserve_lock, flags); - /* Try to find an already reserved cpu. */ - for_each_cpu_mask(cpu, cpu_mask) { - if (smp_cpu_reserved[cpu] != 0) { - smp_cpu_reserved[cpu]++; - /* Found one. */ - goto out; - } - } - /* Reserve a new cpu from cpu_mask. */ - for_each_cpu_mask(cpu, cpu_mask) { - if (cpu_online(cpu)) { - smp_cpu_reserved[cpu]++; - goto out; - } - } - cpu = -ENODEV; -out: - spin_unlock_irqrestore(&smp_reserve_lock, flags); - return cpu; +void smp_cpu_set_polarization(int cpu, int val) +{ + pcpu_devices[cpu].polarization = val; } -void -smp_put_cpu(int cpu) +int smp_cpu_get_polarization(int cpu) { - unsigned long flags; - - spin_lock_irqsave(&smp_reserve_lock, flags); - smp_cpu_reserved[cpu]--; - spin_unlock_irqrestore(&smp_reserve_lock, flags); + return pcpu_devices[cpu].polarization; } -static inline int -cpu_stopped(int cpu) +static struct sclp_cpu_info *smp_get_cpu_info(void) { - __u32 status; - - /* Check for stopped state */ - if (signal_processor_ps(&status, 0, cpu, sigp_sense) == sigp_status_stored) { - if (status & 0x40) - return 1; + static int use_sigp_detection; + struct sclp_cpu_info *info; + int address; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (info && (use_sigp_detection || sclp_get_cpu_info(info))) { + use_sigp_detection = 1; + for (address = 0; address <= MAX_CPU_ADDRESS; address++) { + if (__pcpu_sigp_relax(address, SIGP_SENSE, 0, NULL) == + SIGP_CC_NOT_OPERATIONAL) + continue; + info->cpu[info->configured].address = address; + info->configured++; + } + info->combined = info->configured; } - return 0; + return info; } -/* Upping and downing of CPUs */ +static int smp_add_present_cpu(int cpu); -int -__cpu_up(unsigned int cpu) +static int __smp_rescan_cpus(struct sclp_cpu_info *info, int sysfs_add) { - struct task_struct *idle; - struct _lowcore *cpu_lowcore; - struct stack_frame *sf; - sigp_ccode ccode; - int curr_cpu; + struct pcpu *pcpu; + cpumask_t avail; + int cpu, nr, i; + + nr = 0; + cpumask_xor(&avail, cpu_possible_mask, cpu_present_mask); + cpu = cpumask_first(&avail); + for (i = 0; (i < info->combined) && (cpu < nr_cpu_ids); i++) { + if (info->has_cpu_type && info->cpu[i].type != boot_cpu_type) + continue; + if (pcpu_find_address(cpu_present_mask, info->cpu[i].address)) + continue; + pcpu = pcpu_devices + cpu; + pcpu->address = info->cpu[i].address; + pcpu->state = (i >= info->configured) ? + CPU_STATE_STANDBY : CPU_STATE_CONFIGURED; + smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN); + set_cpu_present(cpu, true); + if (sysfs_add && smp_add_present_cpu(cpu) != 0) + set_cpu_present(cpu, false); + else + nr++; + cpu = cpumask_next(cpu, &avail); + } + return nr; +} - for (curr_cpu = 0; curr_cpu <= 65535; curr_cpu++) { - __cpu_logical_map[cpu] = (__u16) curr_cpu; - if (cpu_stopped(cpu)) +static void __init smp_detect_cpus(void) +{ + unsigned int cpu, c_cpus, s_cpus; + struct sclp_cpu_info *info; + + info = smp_get_cpu_info(); + if (!info) + panic("smp_detect_cpus failed to allocate memory\n"); + if (info->has_cpu_type) { + for (cpu = 0; cpu < info->combined; cpu++) { + if (info->cpu[cpu].address != boot_cpu_address) + continue; + /* The boot cpu dictates the cpu type. */ + boot_cpu_type = info->cpu[cpu].type; break; + } + } + c_cpus = s_cpus = 0; + for (cpu = 0; cpu < info->combined; cpu++) { + if (info->has_cpu_type && info->cpu[cpu].type != boot_cpu_type) + continue; + if (cpu < info->configured) { + smp_get_save_area(c_cpus, info->cpu[cpu].address); + c_cpus++; + } else + s_cpus++; } + pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus); + get_online_cpus(); + __smp_rescan_cpus(info, 0); + put_online_cpus(); + kfree(info); +} - if (!cpu_stopped(cpu)) - return -ENODEV; +/* + * Activate a secondary processor. + */ +static void smp_start_secondary(void *cpuvoid) +{ + S390_lowcore.last_update_clock = get_tod_clock(); + S390_lowcore.restart_stack = (unsigned long) restart_stack; + S390_lowcore.restart_fn = (unsigned long) do_restart; + S390_lowcore.restart_data = 0; + S390_lowcore.restart_source = -1UL; + restore_access_regs(S390_lowcore.access_regs_save_area); + __ctl_load(S390_lowcore.cregs_save_area, 0, 15); + __load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT); + cpu_init(); + preempt_disable(); + init_cpu_timer(); + init_cpu_vtimer(); + pfault_init(); + notify_cpu_starting(smp_processor_id()); + set_cpu_online(smp_processor_id(), true); + inc_irq_stat(CPU_RST); + local_irq_enable(); + cpu_startup_entry(CPUHP_ONLINE); +} - ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]), - cpu, sigp_set_prefix); - if (ccode){ - printk("sigp_set_prefix failed for cpu %d " - "with condition code %d\n", - (int) cpu, (int) ccode); - return -EIO; - } +/* Upping and downing of CPUs */ +int __cpu_up(unsigned int cpu, struct task_struct *tidle) +{ + struct pcpu *pcpu; + int rc; - idle = current_set[cpu]; - cpu_lowcore = lowcore_ptr[cpu]; - cpu_lowcore->kernel_stack = (unsigned long) - idle->thread_info + (THREAD_SIZE); - 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], 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_data.cpu_nr = cpu; - eieio(); - signal_processor(cpu,sigp_restart); + pcpu = pcpu_devices + cpu; + if (pcpu->state != CPU_STATE_CONFIGURED) + return -EIO; + if (pcpu_sigp_retry(pcpu, SIGP_INITIAL_CPU_RESET, 0) != + SIGP_CC_ORDER_CODE_ACCEPTED) + return -EIO; + rc = pcpu_alloc_lowcore(pcpu, cpu); + if (rc) + return rc; + pcpu_prepare_secondary(pcpu, cpu); + pcpu_attach_task(pcpu, tidle); + pcpu_start_fn(pcpu, smp_start_secondary, NULL); while (!cpu_online(cpu)) cpu_relax(); return 0; } -int -__cpu_disable(void) -{ - unsigned long flags; - ec_creg_mask_parms cr_parms; - int cpu = smp_processor_id(); - - spin_lock_irqsave(&smp_reserve_lock, flags); - if (smp_cpu_reserved[cpu] != 0) { - spin_unlock_irqrestore(&smp_reserve_lock, flags); - return -EBUSY; - } - cpu_clear(cpu, cpu_online_map); - -#ifdef CONFIG_PFAULT - /* Disable pfault pseudo page faults on this cpu. */ - if (MACHINE_IS_VM) - pfault_fini(); -#endif - - /* disable all external interrupts */ - - cr_parms.start_ctl = 0; - cr_parms.end_ctl = 0; - 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); - smp_ctl_bit_callback(&cr_parms); - - /* disable all I/O interrupts */ +static unsigned int setup_possible_cpus __initdata; - cr_parms.start_ctl = 6; - cr_parms.end_ctl = 6; - 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); - smp_ctl_bit_callback(&cr_parms); +static int __init _setup_possible_cpus(char *s) +{ + get_option(&s, &setup_possible_cpus); + return 0; +} +early_param("possible_cpus", _setup_possible_cpus); - /* disable most machine checks */ +#ifdef CONFIG_HOTPLUG_CPU - cr_parms.start_ctl = 14; - cr_parms.end_ctl = 14; - 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); +int __cpu_disable(void) +{ + unsigned long cregs[16]; - spin_unlock_irqrestore(&smp_reserve_lock, flags); + /* Handle possible pending IPIs */ + smp_handle_ext_call(); + set_cpu_online(smp_processor_id(), false); + /* Disable pseudo page faults on this cpu. */ + pfault_fini(); + /* Disable interrupt sources via control register. */ + __ctl_store(cregs, 0, 15); + cregs[0] &= ~0x0000ee70UL; /* disable all external interrupts */ + cregs[6] &= ~0xff000000UL; /* disable all I/O interrupts */ + cregs[14] &= ~0x1f000000UL; /* disable most machine checks */ + __ctl_load(cregs, 0, 15); return 0; } -void -__cpu_die(unsigned int cpu) +void __cpu_die(unsigned int cpu) { + struct pcpu *pcpu; + /* Wait until target cpu is down */ - while (!smp_cpu_not_running(cpu)) + pcpu = pcpu_devices + cpu; + while (!pcpu_stopped(pcpu)) cpu_relax(); - printk("Processor %d spun down\n", cpu); + pcpu_free_lowcore(pcpu); + atomic_dec(&init_mm.context.attach_count); + cpumask_clear_cpu(cpu, mm_cpumask(&init_mm)); + if (MACHINE_HAS_TLB_LC) + cpumask_clear_cpu(cpu, &init_mm.context.cpu_attach_mask); } -void -cpu_die(void) +void __noreturn cpu_die(void) { idle_task_exit(); - signal_processor(smp_processor_id(), sigp_stop); - BUG(); - for(;;); + pcpu_sigp_retry(pcpu_devices + smp_processor_id(), SIGP_STOP, 0); + for (;;) ; } -/* - * Cycle through the processors and setup structures. - */ +#endif /* CONFIG_HOTPLUG_CPU */ -void __init smp_prepare_cpus(unsigned int max_cpus) +void __init smp_fill_possible_mask(void) { - unsigned long stack; - unsigned int cpu; - int i; - - /* 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 - */ - print_cpu_info(&S390_lowcore.cpu_data); - - for(i = 0; i < NR_CPUS; i++) { - if (!cpu_possible(i)) - continue; - lowcore_ptr[i] = (struct _lowcore *) - __get_free_pages(GFP_KERNEL|GFP_DMA, - sizeof(void*) == 8 ? 1 : 0); - stack = __get_free_pages(GFP_KERNEL,ASYNC_ORDER); - if (lowcore_ptr[i] == NULL || stack == 0ULL) - panic("smp_boot_cpus failed to allocate memory\n"); - - *(lowcore_ptr[i]) = S390_lowcore; - lowcore_ptr[i]->async_stack = stack + (ASYNC_SIZE); - stack = __get_free_pages(GFP_KERNEL,0); - if (stack == 0ULL) - panic("smp_boot_cpus failed to allocate memory\n"); - lowcore_ptr[i]->panic_stack = stack + (PAGE_SIZE); -#ifndef __s390x__ - if (MACHINE_HAS_IEEE) { - lowcore_ptr[i]->extended_save_area_addr = - (__u32) __get_free_pages(GFP_KERNEL,0); - if (lowcore_ptr[i]->extended_save_area_addr == 0) - panic("smp_boot_cpus failed to " - "allocate memory\n"); - } -#endif - } -#ifndef __s390x__ - if (MACHINE_HAS_IEEE) - ctl_set_bit(14, 29); /* enable extended save area */ -#endif - set_prefix((u32)(unsigned long) lowcore_ptr[smp_processor_id()]); + unsigned int possible, sclp, cpu; - for_each_cpu(cpu) - if (cpu != smp_processor_id()) - smp_create_idle(cpu); + sclp = sclp_get_max_cpu() ?: nr_cpu_ids; + possible = setup_possible_cpus ?: nr_cpu_ids; + possible = min(possible, sclp); + for (cpu = 0; cpu < possible && cpu < nr_cpu_ids; cpu++) + set_cpu_possible(cpu, true); } -void __devinit smp_prepare_boot_cpu(void) +void __init smp_prepare_cpus(unsigned int max_cpus) { - BUG_ON(smp_processor_id() != 0); + /* request the 0x1201 emergency signal external interrupt */ + if (register_external_irq(EXT_IRQ_EMERGENCY_SIG, do_ext_call_interrupt)) + panic("Couldn't request external interrupt 0x1201"); + /* request the 0x1202 external call external interrupt */ + if (register_external_irq(EXT_IRQ_EXTERNAL_CALL, do_ext_call_interrupt)) + panic("Couldn't request external interrupt 0x1202"); + smp_detect_cpus(); +} - cpu_set(0, cpu_online_map); - cpu_set(0, cpu_present_map); - cpu_set(0, cpu_possible_map); +void __init smp_prepare_boot_cpu(void) +{ + struct pcpu *pcpu = pcpu_devices; + + boot_cpu_address = stap(); + pcpu->state = CPU_STATE_CONFIGURED; + pcpu->address = boot_cpu_address; + pcpu->lowcore = (struct _lowcore *)(unsigned long) store_prefix(); + pcpu->async_stack = S390_lowcore.async_stack - ASYNC_SIZE + + STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); + pcpu->panic_stack = S390_lowcore.panic_stack - PAGE_SIZE + + STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); S390_lowcore.percpu_offset = __per_cpu_offset[0]; - current_set[0] = current; + smp_cpu_set_polarization(0, POLARIZATION_UNKNOWN); + set_cpu_present(0, true); + set_cpu_online(0, true); } -void smp_cpus_done(unsigned int max_cpus) +void __init smp_cpus_done(unsigned int max_cpus) { - cpu_present_map = cpu_possible_map; +} + +void __init smp_setup_processor_id(void) +{ + S390_lowcore.cpu_nr = 0; + S390_lowcore.spinlock_lockval = arch_spin_lockval(0); } /* @@ -827,32 +811,253 @@ void smp_cpus_done(unsigned int max_cpus) */ int setup_profiling_timer(unsigned int multiplier) { - return 0; + return 0; } -static DEFINE_PER_CPU(struct cpu, cpu_devices); +#ifdef CONFIG_HOTPLUG_CPU +static ssize_t cpu_configure_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + ssize_t count; + + mutex_lock(&smp_cpu_state_mutex); + count = sprintf(buf, "%d\n", pcpu_devices[dev->id].state); + mutex_unlock(&smp_cpu_state_mutex); + return count; +} -static int __init topology_init(void) +static ssize_t cpu_configure_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) { - int cpu; - int ret; + struct pcpu *pcpu; + int cpu, val, rc; + char delim; - for_each_cpu(cpu) { - ret = register_cpu(&per_cpu(cpu_devices, cpu), cpu, NULL); - if (ret) - printk(KERN_WARNING "topology_init: register_cpu %d " - "failed (%d)\n", cpu, ret); + 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; + /* disallow configuration changes of online cpus and cpu 0 */ + cpu = dev->id; + if (cpu_online(cpu) || cpu == 0) + goto out; + pcpu = pcpu_devices + cpu; + rc = 0; + switch (val) { + case 0: + if (pcpu->state != CPU_STATE_CONFIGURED) + break; + rc = sclp_cpu_deconfigure(pcpu->address); + if (rc) + break; + pcpu->state = CPU_STATE_STANDBY; + smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN); + topology_expect_change(); + break; + case 1: + if (pcpu->state != CPU_STATE_STANDBY) + break; + rc = sclp_cpu_configure(pcpu->address); + if (rc) + break; + pcpu->state = CPU_STATE_CONFIGURED; + smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN); + topology_expect_change(); + break; + default: + break; } +out: + mutex_unlock(&smp_cpu_state_mutex); + put_online_cpus(); + return rc ? rc : count; +} +static DEVICE_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); +#endif /* CONFIG_HOTPLUG_CPU */ + +static ssize_t show_cpu_address(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", pcpu_devices[dev->id].address); +} +static DEVICE_ATTR(address, 0444, show_cpu_address, NULL); + +static struct attribute *cpu_common_attrs[] = { +#ifdef CONFIG_HOTPLUG_CPU + &dev_attr_configure.attr, +#endif + &dev_attr_address.attr, + NULL, +}; + +static struct attribute_group cpu_common_attr_group = { + .attrs = cpu_common_attrs, +}; + +static ssize_t show_idle_count(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct s390_idle_data *idle = &per_cpu(s390_idle, dev->id); + unsigned long long idle_count; + unsigned int sequence; + + do { + sequence = ACCESS_ONCE(idle->sequence); + idle_count = ACCESS_ONCE(idle->idle_count); + if (ACCESS_ONCE(idle->clock_idle_enter)) + idle_count++; + } while ((sequence & 1) || (ACCESS_ONCE(idle->sequence) != sequence)); + return sprintf(buf, "%llu\n", idle_count); +} +static DEVICE_ATTR(idle_count, 0444, show_idle_count, NULL); + +static ssize_t show_idle_time(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct s390_idle_data *idle = &per_cpu(s390_idle, dev->id); + unsigned long long now, idle_time, idle_enter, idle_exit; + unsigned int sequence; + + do { + now = get_tod_clock(); + sequence = ACCESS_ONCE(idle->sequence); + idle_time = ACCESS_ONCE(idle->idle_time); + idle_enter = ACCESS_ONCE(idle->clock_idle_enter); + idle_exit = ACCESS_ONCE(idle->clock_idle_exit); + } while ((sequence & 1) || (ACCESS_ONCE(idle->sequence) != sequence)); + idle_time += idle_enter ? ((idle_exit ? : now) - idle_enter) : 0; + return sprintf(buf, "%llu\n", idle_time >> 12); +} +static DEVICE_ATTR(idle_time_us, 0444, show_idle_time, NULL); + +static struct attribute *cpu_online_attrs[] = { + &dev_attr_idle_count.attr, + &dev_attr_idle_time_us.attr, + NULL, +}; + +static struct attribute_group cpu_online_attr_group = { + .attrs = cpu_online_attrs, +}; + +static int smp_cpu_notify(struct notifier_block *self, unsigned long action, + void *hcpu) +{ + unsigned int cpu = (unsigned int)(long)hcpu; + struct cpu *c = pcpu_devices[cpu].cpu; + struct device *s = &c->dev; + int err = 0; + + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_ONLINE: + err = sysfs_create_group(&s->kobj, &cpu_online_attr_group); + break; + case CPU_DEAD: + sysfs_remove_group(&s->kobj, &cpu_online_attr_group); + break; + } + return notifier_from_errno(err); +} + +static int smp_add_present_cpu(int cpu) +{ + struct device *s; + struct cpu *c; + int rc; + + c = kzalloc(sizeof(*c), GFP_KERNEL); + if (!c) + return -ENOMEM; + pcpu_devices[cpu].cpu = c; + s = &c->dev; + 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)) { + rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group); + if (rc) + goto out_online; + } + rc = topology_cpu_init(c); + if (rc) + goto out_topology; return 0; + +out_topology: + if (cpu_online(cpu)) + sysfs_remove_group(&s->kobj, &cpu_online_attr_group); +out_online: + sysfs_remove_group(&s->kobj, &cpu_common_attr_group); +out_cpu: +#ifdef CONFIG_HOTPLUG_CPU + unregister_cpu(c); +#endif +out: + return rc; } -subsys_initcall(topology_init); +#ifdef CONFIG_HOTPLUG_CPU -EXPORT_SYMBOL(cpu_possible_map); -EXPORT_SYMBOL(lowcore_ptr); -EXPORT_SYMBOL(smp_ctl_set_bit); -EXPORT_SYMBOL(smp_ctl_clear_bit); -EXPORT_SYMBOL(smp_call_function); -EXPORT_SYMBOL(smp_get_cpu); -EXPORT_SYMBOL(smp_put_cpu); +int __ref smp_rescan_cpus(void) +{ + struct sclp_cpu_info *info; + int nr; + + info = smp_get_cpu_info(); + if (!info) + return -ENOMEM; + get_online_cpus(); + mutex_lock(&smp_cpu_state_mutex); + nr = __smp_rescan_cpus(info, 1); + mutex_unlock(&smp_cpu_state_mutex); + put_online_cpus(); + kfree(info); + if (nr) + topology_schedule_update(); + return 0; +} + +static ssize_t __ref rescan_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + int rc; + + rc = smp_rescan_cpus(); + return rc ? rc : count; +} +static DEVICE_ATTR(rescan, 0200, NULL, rescan_store); +#endif /* CONFIG_HOTPLUG_CPU */ + +static int __init s390_smp_init(void) +{ + int cpu, rc = 0; + +#ifdef CONFIG_HOTPLUG_CPU + rc = device_create_file(cpu_subsys.dev_root, &dev_attr_rescan); + if (rc) + return rc; +#endif + cpu_notifier_register_begin(); + for_each_present_cpu(cpu) { + rc = smp_add_present_cpu(cpu); + if (rc) + goto out; + } + + __hotcpu_notifier(smp_cpu_notify, 0); +out: + cpu_notifier_register_done(); + return rc; +} +subsys_initcall(s390_smp_init); |