diff options
Diffstat (limited to 'arch/sh/kernel/smp.c')
| -rw-r--r-- | arch/sh/kernel/smp.c | 160 |
1 files changed, 140 insertions, 20 deletions
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 002cc612dee..86cd6f94b53 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -3,7 +3,7 @@ * * SMP support for the SuperH processors. * - * Copyright (C) 2002 - 2008 Paul Mundt + * Copyright (C) 2002 - 2010 Paul Mundt * Copyright (C) 2006 - 2007 Akio Idehara * * This file is subject to the terms and conditions of the GNU General Public @@ -31,7 +31,20 @@ int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ -static inline void __init smp_store_cpu_info(unsigned int cpu) +struct plat_smp_ops *mp_ops = NULL; + +/* State of each CPU */ +DEFINE_PER_CPU(int, cpu_state) = { 0 }; + +void __cpuinit register_smp_ops(struct plat_smp_ops *ops) +{ + if (mp_ops) + printk(KERN_WARNING "Overriding previously set SMP ops\n"); + + mp_ops = ops; +} + +static inline void __cpuinit smp_store_cpu_info(unsigned int cpu) { struct sh_cpuinfo *c = cpu_data + cpu; @@ -46,14 +59,14 @@ void __init smp_prepare_cpus(unsigned int max_cpus) init_new_context(current, &init_mm); current_thread_info()->cpu = cpu; - plat_prepare_cpus(max_cpus); + mp_ops->prepare_cpus(max_cpus); #ifndef CONFIG_HOTPLUG_CPU init_cpu_present(&cpu_possible_map); #endif } -void __devinit smp_prepare_boot_cpu(void) +void __init smp_prepare_boot_cpu(void) { unsigned int cpu = smp_processor_id(); @@ -62,37 +75,137 @@ void __devinit smp_prepare_boot_cpu(void) set_cpu_online(cpu, true); set_cpu_possible(cpu, true); + + per_cpu(cpu_state, cpu) = CPU_ONLINE; +} + +#ifdef CONFIG_HOTPLUG_CPU +void native_cpu_die(unsigned int cpu) +{ + unsigned int i; + + for (i = 0; i < 10; i++) { + smp_rmb(); + if (per_cpu(cpu_state, cpu) == CPU_DEAD) { + if (system_state == SYSTEM_RUNNING) + pr_info("CPU %u is now offline\n", cpu); + + return; + } + + msleep(100); + } + + pr_err("CPU %u didn't die...\n", cpu); +} + +int native_cpu_disable(unsigned int cpu) +{ + return cpu == 0 ? -EPERM : 0; +} + +void play_dead_common(void) +{ + idle_task_exit(); + irq_ctx_exit(raw_smp_processor_id()); + mb(); + + __get_cpu_var(cpu_state) = CPU_DEAD; + local_irq_disable(); +} + +void native_play_dead(void) +{ + play_dead_common(); } +int __cpu_disable(void) +{ + unsigned int cpu = smp_processor_id(); + struct task_struct *p; + int ret; + + ret = mp_ops->cpu_disable(cpu); + if (ret) + return ret; + + /* + * Take this CPU offline. Once we clear this, we can't return, + * and we must not schedule until we're ready to give up the cpu. + */ + set_cpu_online(cpu, false); + + /* + * OK - migrate IRQs away from this CPU + */ + migrate_irqs(); + + /* + * Stop the local timer for this CPU. + */ + local_timer_stop(cpu); + + /* + * Flush user cache and TLB mappings, and then remove this CPU + * from the vm mask set of all processes. + */ + flush_cache_all(); + local_flush_tlb_all(); + + read_lock(&tasklist_lock); + for_each_process(p) + if (p->mm) + cpumask_clear_cpu(cpu, mm_cpumask(p->mm)); + read_unlock(&tasklist_lock); + + return 0; +} +#else /* ... !CONFIG_HOTPLUG_CPU */ +int native_cpu_disable(void) +{ + return -ENOSYS; +} + +void native_cpu_die(unsigned int cpu) +{ + /* We said "no" in __cpu_disable */ + BUG(); +} + +void native_play_dead(void) +{ + BUG(); +} +#endif + asmlinkage void __cpuinit start_secondary(void) { - unsigned int cpu; + unsigned int cpu = smp_processor_id(); struct mm_struct *mm = &init_mm; enable_mmu(); atomic_inc(&mm->mm_count); atomic_inc(&mm->mm_users); current->active_mm = mm; - BUG_ON(current->mm); enter_lazy_tlb(mm, current); + local_flush_tlb_all(); per_cpu_trap_init(); preempt_disable(); - notify_cpu_starting(smp_processor_id()); + notify_cpu_starting(cpu); local_irq_enable(); - cpu = smp_processor_id(); - /* Enable local timers */ local_timer_setup(cpu); calibrate_delay(); smp_store_cpu_info(cpu); - cpu_set(cpu, cpu_online_map); + set_cpu_online(cpu, true); + per_cpu(cpu_state, cpu) = CPU_ONLINE; cpu_idle(); } @@ -111,12 +224,19 @@ int __cpuinit __cpu_up(unsigned int cpu) struct task_struct *tsk; unsigned long timeout; - tsk = fork_idle(cpu); - if (IS_ERR(tsk)) { - printk(KERN_ERR "Failed forking idle task for cpu %d\n", cpu); - return PTR_ERR(tsk); + tsk = cpu_data[cpu].idle; + if (!tsk) { + tsk = fork_idle(cpu); + if (IS_ERR(tsk)) { + pr_err("Failed forking idle task for cpu %d\n", cpu); + return PTR_ERR(tsk); + } + + cpu_data[cpu].idle = tsk; } + per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; + /* Fill in data in head.S for secondary cpus */ stack_start.sp = tsk->thread.sp; stack_start.thread_info = tsk->stack; @@ -127,7 +247,7 @@ int __cpuinit __cpu_up(unsigned int cpu) (unsigned long)&stack_start + sizeof(stack_start)); wmb(); - plat_start_cpu(cpu, (unsigned long)_stext); + mp_ops->start_cpu(cpu, (unsigned long)_stext); timeout = jiffies + HZ; while (time_before(jiffies, timeout)) { @@ -135,6 +255,7 @@ int __cpuinit __cpu_up(unsigned int cpu) break; udelay(10); + barrier(); } if (cpu_online(cpu)) @@ -159,7 +280,7 @@ void __init smp_cpus_done(unsigned int max_cpus) void smp_send_reschedule(int cpu) { - plat_send_ipi(cpu, SMP_MSG_RESCHEDULE); + mp_ops->send_ipi(cpu, SMP_MSG_RESCHEDULE); } void smp_send_stop(void) @@ -172,12 +293,12 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask) int cpu; for_each_cpu(cpu, mask) - plat_send_ipi(cpu, SMP_MSG_FUNCTION); + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION); } void arch_send_call_function_single_ipi(int cpu) { - plat_send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); } void smp_timer_broadcast(const struct cpumask *mask) @@ -185,7 +306,7 @@ void smp_timer_broadcast(const struct cpumask *mask) int cpu; for_each_cpu(cpu, mask) - plat_send_ipi(cpu, SMP_MSG_TIMER); + mp_ops->send_ipi(cpu, SMP_MSG_TIMER); } static void ipi_timer(void) @@ -249,7 +370,6 @@ static void flush_tlb_mm_ipi(void *mm) * behalf of debugees, kswapd stealing pages from another process etc). * Kanoj 07/00. */ - void flush_tlb_mm(struct mm_struct *mm) { preempt_disable(); |