diff options
Diffstat (limited to 'arch/s390/kernel/smp.c')
| -rw-r--r-- | arch/s390/kernel/smp.c | 74 |
1 files changed, 45 insertions, 29 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index fd8e3111a4e..56c16876b91 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -49,6 +49,7 @@ #include <asm/sclp.h> #include <asm/cputime.h> #include <asm/vdso.h> +#include <asm/cpu.h> #include "entry.h" static struct task_struct *current_set[NR_CPUS]; @@ -70,6 +71,23 @@ static DEFINE_PER_CPU(struct cpu, cpu_devices); static void smp_ext_bitcall(int, ec_bit_sig); +static int cpu_stopped(int cpu) +{ + __u32 status; + + switch (signal_processor_ps(&status, 0, cpu, sigp_sense)) { + case sigp_order_code_accepted: + case sigp_status_stored: + /* Check for stopped and check stop state */ + if (status & 0x50) + return 1; + break; + default: + break; + } + return 0; +} + void smp_send_stop(void) { int cpu, rc; @@ -86,7 +104,7 @@ void smp_send_stop(void) rc = signal_processor(cpu, sigp_stop); } while (rc == sigp_busy); - while (!smp_cpu_not_running(cpu)) + while (!cpu_stopped(cpu)) cpu_relax(); } } @@ -269,19 +287,6 @@ 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; @@ -300,7 +305,7 @@ static int smp_rescan_cpus_sigp(cpumask_t avail) logical_cpu = cpumask_first(&avail); if (logical_cpu >= nr_cpu_ids) return 0; - for (cpu_id = 0; cpu_id <= 65535; cpu_id++) { + for (cpu_id = 0; cpu_id <= MAX_CPU_ADDRESS; cpu_id++) { if (cpu_known(cpu_id)) continue; __cpu_logical_map[logical_cpu] = cpu_id; @@ -379,7 +384,7 @@ static void __init smp_detect_cpus(void) /* Use sigp detection algorithm if sclp doesn't work. */ if (sclp_get_cpu_info(info)) { smp_use_sigp_detection = 1; - for (cpu = 0; cpu <= 65535; cpu++) { + for (cpu = 0; cpu <= MAX_CPU_ADDRESS; cpu++) { if (cpu == boot_cpu_addr) continue; __cpu_logical_map[CPU_INIT_NO] = cpu; @@ -635,7 +640,7 @@ int __cpu_disable(void) void __cpu_die(unsigned int cpu) { /* Wait until target cpu is down */ - while (!smp_cpu_not_running(cpu)) + while (!cpu_stopped(cpu)) cpu_relax(); smp_free_lowcore(cpu); pr_info("Processor %d stopped\n", cpu); @@ -687,13 +692,14 @@ void __init smp_prepare_cpus(unsigned int max_cpus) #ifndef CONFIG_64BIT if (MACHINE_HAS_IEEE) lowcore->extended_save_area_addr = (u32) save_area; -#else - if (vdso_alloc_per_cpu(smp_processor_id(), lowcore)) - BUG(); #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); @@ -856,13 +862,20 @@ static ssize_t show_idle_count(struct sys_device *dev, { struct s390_idle_data *idle; unsigned long long idle_count; + unsigned int sequence; idle = &per_cpu(s390_idle, dev->id); - spin_lock(&idle->lock); +repeat: + sequence = idle->sequence; + smp_rmb(); + if (sequence & 1) + goto repeat; idle_count = idle->idle_count; if (idle->idle_enter) idle_count++; - spin_unlock(&idle->lock); + 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); @@ -872,15 +885,22 @@ static ssize_t show_idle_time(struct sys_device *dev, { struct s390_idle_data *idle; unsigned long long now, idle_time, idle_enter; + unsigned int sequence; idle = &per_cpu(s390_idle, dev->id); - spin_lock(&idle->lock); 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; - spin_unlock(&idle->lock); + 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); @@ -908,11 +928,7 @@ static int __cpuinit smp_cpu_notify(struct notifier_block *self, case CPU_ONLINE: case CPU_ONLINE_FROZEN: idle = &per_cpu(s390_idle, cpu); - spin_lock_irq(&idle->lock); - idle->idle_enter = 0; - idle->idle_time = 0; - idle->idle_count = 0; - spin_unlock_irq(&idle->lock); + memset(idle, 0, sizeof(struct s390_idle_data)); if (sysfs_create_group(&s->kobj, &cpu_online_attr_group)) return NOTIFY_BAD; break; |