diff options
| -rw-r--r-- | include/linux/irqdesc.h | 7 | ||||
| -rw-r--r-- | kernel/cpu.c | 22 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 4 |
3 files changed, 27 insertions, 6 deletions
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h index 624a668..fcea4e4 100644 --- a/include/linux/irqdesc.h +++ b/include/linux/irqdesc.h @@ -87,7 +87,12 @@ struct irq_desc { const char *name; } ____cacheline_internodealigned_in_smp; -#ifndef CONFIG_SPARSE_IRQ +#ifdef CONFIG_SPARSE_IRQ +extern void irq_lock_sparse(void); +extern void irq_unlock_sparse(void); +#else +static inline void irq_lock_sparse(void) { } +static inline void irq_unlock_sparse(void) { } extern struct irq_desc irq_desc[NR_IRQS]; #endif diff --git a/kernel/cpu.c b/kernel/cpu.c index 9c9c9fa..6a37454 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -21,6 +21,7 @@ #include <linux/suspend.h> #include <linux/lockdep.h> #include <linux/tick.h> +#include <linux/irq.h> #include <trace/events/power.h> #include "smpboot.h" @@ -392,13 +393,19 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) smpboot_park_threads(cpu); /* - * So now all preempt/rcu users must observe !cpu_active(). + * Prevent irq alloc/free while the dying cpu reorganizes the + * interrupt affinities. */ + irq_lock_sparse(); + /* + * So now all preempt/rcu users must observe !cpu_active(). + */ err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu)); if (err) { /* CPU didn't die: tell everyone. Can't complain. */ cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu); + irq_unlock_sparse(); goto out_release; } BUG_ON(cpu_online(cpu)); @@ -415,6 +422,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) smp_mb(); /* Read from cpu_dead_idle before __cpu_die(). */ per_cpu(cpu_dead_idle, cpu) = false; + /* Interrupts are moved away from the dying cpu, reenable alloc/free */ + irq_unlock_sparse(); + hotplug_cpu__broadcast_tick_pull(cpu); /* This actually kills the CPU. */ __cpu_die(cpu); @@ -517,8 +527,18 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen) goto out_notify; } + /* + * Some architectures have to walk the irq descriptors to + * setup the vector space for the cpu which comes online. + * Prevent irq alloc/free across the bringup. + */ + irq_lock_sparse(); + /* Arch-specific enabling code. */ ret = __cpu_up(cpu, idle); + + irq_unlock_sparse(); + if (ret != 0) goto out_notify; BUG_ON(!cpu_online(cpu)); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 4834ee8..61008b8 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -76,12 +76,8 @@ extern void unmask_threaded_irq(struct irq_desc *desc); #ifdef CONFIG_SPARSE_IRQ static inline void irq_mark_irq(unsigned int irq) { } -extern void irq_lock_sparse(void); -extern void irq_unlock_sparse(void); #else extern void irq_mark_irq(unsigned int irq); -static inline void irq_lock_sparse(void) { } -static inline void irq_unlock_sparse(void) { } #endif extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr); |
