diff options
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/head_32.S | 9 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_64.S | 7 | ||||
-rw-r--r-- | arch/powerpc/kernel/idle_power4.S | 21 | ||||
-rw-r--r-- | arch/powerpc/kernel/irq.c | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/smp.c | 153 | ||||
-rw-r--r-- | arch/powerpc/kernel/time.c | 15 |
6 files changed, 126 insertions, 82 deletions
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index 98c4b29a56f4..c5c24beb8387 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -890,6 +890,15 @@ __secondary_start: mtspr SPRN_SRR1,r4 SYNC RFI + +_GLOBAL(start_secondary_resume) + /* Reset stack */ + rlwinm r1,r1,0,0,(31-THREAD_SHIFT) /* current_thread_info() */ + addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD + li r3,0 + std r3,0(r1) /* Zero the stack frame pointer */ + bl start_secondary + b . #endif /* CONFIG_SMP */ #ifdef CONFIG_KVM_BOOK3S_HANDLER diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 782f23df7c85..271140b38b6f 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -536,6 +536,13 @@ _GLOBAL(pmac_secondary_start) add r13,r13,r4 /* for this processor. */ mtspr SPRN_SPRG_PACA,r13 /* Save vaddr of paca in an SPRG*/ + /* Mark interrupts soft and hard disabled (they might be enabled + * in the PACA when doing hotplug) + */ + li r0,0 + stb r0,PACASOFTIRQEN(r13) + stb r0,PACAHARDIRQEN(r13) + /* Create a temp kernel stack for use before relocation is on. */ ld r1,PACAEMERGSP(r13) subi r1,r1,STACK_FRAME_OVERHEAD diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S index 5328709eeedc..ba3195478600 100644 --- a/arch/powerpc/kernel/idle_power4.S +++ b/arch/powerpc/kernel/idle_power4.S @@ -53,24 +53,3 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) isync b 1b -_GLOBAL(power4_cpu_offline_powersave) - /* Go to NAP now */ - mfmsr r7 - rldicl r0,r7,48,1 - rotldi r0,r0,16 - mtmsrd r0,1 /* hard-disable interrupts */ - li r0,1 - li r6,0 - stb r0,PACAHARDIRQEN(r13) /* we'll hard-enable shortly */ - stb r6,PACASOFTIRQEN(r13) /* soft-disable irqs */ -BEGIN_FTR_SECTION - DSSALL - sync -END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) - ori r7,r7,MSR_EE - oris r7,r7,MSR_POW@h - sync - isync - mtmsrd r7 - isync - blr diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 63625e0650b5..f621b7d2d869 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -246,12 +246,13 @@ u64 arch_irq_stat_cpu(unsigned int cpu) } #ifdef CONFIG_HOTPLUG_CPU -void fixup_irqs(const struct cpumask *map) +void migrate_irqs(void) { struct irq_desc *desc; unsigned int irq; static int warned; cpumask_var_t mask; + const struct cpumask *map = cpu_online_mask; alloc_cpumask_var(&mask, GFP_KERNEL); diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 981360509172..cbdbb14be4b0 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -57,6 +57,25 @@ #define DBG(fmt...) #endif + +/* Store all idle threads, this can be reused instead of creating +* a new thread. Also avoids complicated thread destroy functionality +* for idle threads. +*/ +#ifdef CONFIG_HOTPLUG_CPU +/* + * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is + * removed after init for !CONFIG_HOTPLUG_CPU. + */ +static DEFINE_PER_CPU(struct task_struct *, idle_thread_array); +#define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x)) +#define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p)) +#else +static struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ; +#define get_idle_for_cpu(x) (idle_thread_array[(x)]) +#define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p)) +#endif + struct thread_info *secondary_ti; DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map); @@ -238,23 +257,6 @@ static void __devinit smp_store_cpu_info(int id) per_cpu(cpu_pvr, id) = mfspr(SPRN_PVR); } -static void __init smp_create_idle(unsigned int cpu) -{ - struct task_struct *p; - - /* create a process for the processor */ - p = fork_idle(cpu); - if (IS_ERR(p)) - panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); -#ifdef CONFIG_PPC64 - paca[cpu].__current = p; - paca[cpu].kstack = (unsigned long) task_thread_info(p) - + THREAD_SIZE - STACK_FRAME_OVERHEAD; -#endif - current_set[cpu] = task_thread_info(p); - task_thread_info(p)->cpu = cpu; -} - void __init smp_prepare_cpus(unsigned int max_cpus) { unsigned int cpu; @@ -288,10 +290,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus) max_cpus = NR_CPUS; else max_cpus = 1; - - for_each_possible_cpu(cpu) - if (cpu != boot_cpuid) - smp_create_idle(cpu); } void __devinit smp_prepare_boot_cpu(void) @@ -305,7 +303,7 @@ void __devinit smp_prepare_boot_cpu(void) #ifdef CONFIG_HOTPLUG_CPU /* State of each CPU during hotplug phases */ -DEFINE_PER_CPU(int, cpu_state) = { 0 }; +static DEFINE_PER_CPU(int, cpu_state) = { 0 }; int generic_cpu_disable(void) { @@ -317,30 +315,8 @@ int generic_cpu_disable(void) set_cpu_online(cpu, false); #ifdef CONFIG_PPC64 vdso_data->processorCount--; - fixup_irqs(cpu_online_mask); -#endif - return 0; -} - -int generic_cpu_enable(unsigned int cpu) -{ - /* Do the normal bootup if we haven't - * already bootstrapped. */ - if (system_state != SYSTEM_RUNNING) - return -ENOSYS; - - /* get the target out of it's holding state */ - per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; - smp_wmb(); - - while (!cpu_online(cpu)) - cpu_relax(); - -#ifdef CONFIG_PPC64 - fixup_irqs(cpu_online_mask); - /* counter the irq disable in fixup_irqs */ - local_irq_enable(); #endif + migrate_irqs(); return 0; } @@ -362,37 +338,89 @@ void generic_mach_cpu_die(void) unsigned int cpu; local_irq_disable(); + idle_task_exit(); cpu = smp_processor_id(); printk(KERN_DEBUG "CPU%d offline\n", cpu); __get_cpu_var(cpu_state) = CPU_DEAD; smp_wmb(); while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE) cpu_relax(); - set_cpu_online(cpu, true); - local_irq_enable(); +} + +void generic_set_cpu_dead(unsigned int cpu) +{ + per_cpu(cpu_state, cpu) = CPU_DEAD; } #endif -static int __devinit cpu_enable(unsigned int cpu) +struct create_idle { + struct work_struct work; + struct task_struct *idle; + struct completion done; + int cpu; +}; + +static void __cpuinit do_fork_idle(struct work_struct *work) { - if (smp_ops && smp_ops->cpu_enable) - return smp_ops->cpu_enable(cpu); + struct create_idle *c_idle = + container_of(work, struct create_idle, work); + + c_idle->idle = fork_idle(c_idle->cpu); + complete(&c_idle->done); +} + +static int __cpuinit create_idle(unsigned int cpu) +{ + struct thread_info *ti; + struct create_idle c_idle = { + .cpu = cpu, + .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done), + }; + INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle); + + c_idle.idle = get_idle_for_cpu(cpu); + + /* We can't use kernel_thread since we must avoid to + * reschedule the child. We use a workqueue because + * we want to fork from a kernel thread, not whatever + * userspace process happens to be trying to online us. + */ + if (!c_idle.idle) { + schedule_work(&c_idle.work); + wait_for_completion(&c_idle.done); + } else + init_idle(c_idle.idle, cpu); + if (IS_ERR(c_idle.idle)) { + pr_err("Failed fork for CPU %u: %li", cpu, PTR_ERR(c_idle.idle)); + return PTR_ERR(c_idle.idle); + } + ti = task_thread_info(c_idle.idle); + +#ifdef CONFIG_PPC64 + paca[cpu].__current = c_idle.idle; + paca[cpu].kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD; +#endif + ti->cpu = cpu; + current_set[cpu] = ti; - return -ENOSYS; + return 0; } int __cpuinit __cpu_up(unsigned int cpu) { - int c; + int rc, c; secondary_ti = current_set[cpu]; - if (!cpu_enable(cpu)) - return 0; if (smp_ops == NULL || (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu))) return -EINVAL; + /* Make sure we have an idle thread */ + rc = create_idle(cpu); + if (rc) + return rc; + /* Make sure callin-map entry is 0 (can be leftover a CPU * hotplug */ @@ -502,7 +530,7 @@ static struct device_node *cpu_to_l2cache(int cpu) } /* Activate a secondary processor. */ -int __devinit start_secondary(void *unused) +void __devinit start_secondary(void *unused) { unsigned int cpu = smp_processor_id(); struct device_node *l2_cache; @@ -523,6 +551,10 @@ int __devinit start_secondary(void *unused) secondary_cpu_time_init(); +#ifdef CONFIG_PPC64 + if (system_state == SYSTEM_RUNNING) + vdso_data->processorCount++; +#endif ipi_call_lock(); notify_cpu_starting(cpu); set_cpu_online(cpu, true); @@ -558,7 +590,8 @@ int __devinit start_secondary(void *unused) local_irq_enable(); cpu_idle(); - return 0; + + BUG(); } int setup_profiling_timer(unsigned int multiplier) @@ -585,7 +618,11 @@ void __init smp_cpus_done(unsigned int max_cpus) free_cpumask_var(old_mask); + if (smp_ops && smp_ops->bringup_done) + smp_ops->bringup_done(); + dump_numa_cpu_topology(); + } int arch_sd_sibling_asym_packing(void) @@ -660,5 +697,9 @@ void cpu_die(void) { if (ppc_md.cpu_die) ppc_md.cpu_die(); + + /* If we return, we re-enter start_secondary */ + start_secondary_resume(); } + #endif diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index aa9269600ca2..375480c56eb9 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -577,14 +577,21 @@ void timer_interrupt(struct pt_regs * regs) struct clock_event_device *evt = &decrementer->event; u64 now; + /* Ensure a positive value is written to the decrementer, or else + * some CPUs will continue to take decrementer exceptions. + */ + set_dec(DECREMENTER_MAX); + + /* Some implementations of hotplug will get timer interrupts while + * offline, just ignore these + */ + if (!cpu_online(smp_processor_id())) + return; + trace_timer_interrupt_entry(regs); __get_cpu_var(irq_stat).timer_irqs++; - /* Ensure a positive value is written to the decrementer, or else - * some CPUs will continuue to take decrementer exceptions */ - set_dec(DECREMENTER_MAX); - #if defined(CONFIG_PPC32) && defined(CONFIG_PMAC) if (atomic_read(&ppc_n_lost_interrupts) != 0) do_IRQ(regs); |