diff options
| -rw-r--r-- | include/linux/interrupt.h | 22 | ||||
| -rw-r--r-- | kernel/softirq.c | 131 |
2 files changed, 0 insertions, 153 deletions
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index c9e831dc80bcc..db43b58a3355c 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -11,8 +11,6 @@ #include <linux/irqnr.h> #include <linux/hardirq.h> #include <linux/irqflags.h> -#include <linux/smp.h> -#include <linux/percpu.h> #include <linux/hrtimer.h> #include <linux/kref.h> #include <linux/workqueue.h> @@ -392,15 +390,6 @@ extern void __raise_softirq_irqoff(unsigned int nr); extern void raise_softirq_irqoff(unsigned int nr); extern void raise_softirq(unsigned int nr); -/* This is the worklist that queues up per-cpu softirq work. - * - * send_remote_sendirq() adds work to these lists, and - * the softirq handler itself dequeues from them. The queues - * are protected by disabling local cpu interrupts and they must - * only be accessed by the local cpu that they are for. - */ -DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list); - DECLARE_PER_CPU(struct task_struct *, ksoftirqd); static inline struct task_struct *this_cpu_ksoftirqd(void) @@ -408,17 +397,6 @@ static inline struct task_struct *this_cpu_ksoftirqd(void) return this_cpu_read(ksoftirqd); } -/* Try to send a softirq to a remote cpu. If this cannot be done, the - * work will be queued to the local cpu. - */ -extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq); - -/* Like send_remote_softirq(), but the caller must disable local cpu interrupts - * and compute the current cpu, passed in as 'this_cpu'. - */ -extern void __send_remote_softirq(struct call_single_data *cp, int cpu, - int this_cpu, int softirq); - /* Tasklets --- multithreaded analogue of BHs. Main feature differing them of generic softirqs: tasklet diff --git a/kernel/softirq.c b/kernel/softirq.c index b24988353458c..11025ccc06dd1 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -6,8 +6,6 @@ * Distribute under GPLv2. * * Rewritten. Old one was good in 2.2, but in 2.3 it was immoral. --ANK (990903) - * - * Remote softirq infrastructure is by Jens Axboe. */ #include <linux/export.h> @@ -627,146 +625,17 @@ void tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer, } EXPORT_SYMBOL_GPL(tasklet_hrtimer_init); -/* - * Remote softirq bits - */ - -DEFINE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list); -EXPORT_PER_CPU_SYMBOL(softirq_work_list); - -static void __local_trigger(struct call_single_data *cp, int softirq) -{ - struct list_head *head = &__get_cpu_var(softirq_work_list[softirq]); - - list_add_tail(&cp->list, head); - - /* Trigger the softirq only if the list was previously empty. */ - if (head->next == &cp->list) - raise_softirq_irqoff(softirq); -} - -#ifdef CONFIG_USE_GENERIC_SMP_HELPERS -static void remote_softirq_receive(void *data) -{ - struct call_single_data *cp = data; - unsigned long flags; - int softirq; - - softirq = *(int *)cp->info; - local_irq_save(flags); - __local_trigger(cp, softirq); - local_irq_restore(flags); -} - -static int __try_remote_softirq(struct call_single_data *cp, int cpu, int softirq) -{ - if (cpu_online(cpu)) { - cp->func = remote_softirq_receive; - cp->info = &softirq; - cp->flags = 0; - - __smp_call_function_single(cpu, cp, 0); - return 0; - } - return 1; -} -#else /* CONFIG_USE_GENERIC_SMP_HELPERS */ -static int __try_remote_softirq(struct call_single_data *cp, int cpu, int softirq) -{ - return 1; -} -#endif - -/** - * __send_remote_softirq - try to schedule softirq work on a remote cpu - * @cp: private SMP call function data area - * @cpu: the remote cpu - * @this_cpu: the currently executing cpu - * @softirq: the softirq for the work - * - * Attempt to schedule softirq work on a remote cpu. If this cannot be - * done, the work is instead queued up on the local cpu. - * - * Interrupts must be disabled. - */ -void __send_remote_softirq(struct call_single_data *cp, int cpu, int this_cpu, int softirq) -{ - if (cpu == this_cpu || __try_remote_softirq(cp, cpu, softirq)) - __local_trigger(cp, softirq); -} -EXPORT_SYMBOL(__send_remote_softirq); - -/** - * send_remote_softirq - try to schedule softirq work on a remote cpu - * @cp: private SMP call function data area - * @cpu: the remote cpu - * @softirq: the softirq for the work - * - * Like __send_remote_softirq except that disabling interrupts and - * computing the current cpu is done for the caller. - */ -void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq) -{ - unsigned long flags; - int this_cpu; - - local_irq_save(flags); - this_cpu = smp_processor_id(); - __send_remote_softirq(cp, cpu, this_cpu, softirq); - local_irq_restore(flags); -} -EXPORT_SYMBOL(send_remote_softirq); - -static int remote_softirq_cpu_notify(struct notifier_block *self, - unsigned long action, void *hcpu) -{ - /* - * If a CPU goes away, splice its entries to the current CPU - * and trigger a run of the softirq - */ - if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) { - int cpu = (unsigned long) hcpu; - int i; - - local_irq_disable(); - for (i = 0; i < NR_SOFTIRQS; i++) { - struct list_head *head = &per_cpu(softirq_work_list[i], cpu); - struct list_head *local_head; - - if (list_empty(head)) - continue; - - local_head = &__get_cpu_var(softirq_work_list[i]); - list_splice_init(head, local_head); - raise_softirq_irqoff(i); - } - local_irq_enable(); - } - - return NOTIFY_OK; -} - -static struct notifier_block remote_softirq_cpu_notifier = { - .notifier_call = remote_softirq_cpu_notify, -}; - void __init softirq_init(void) { int cpu; for_each_possible_cpu(cpu) { - int i; - per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head; per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head; - for (i = 0; i < NR_SOFTIRQS; i++) - INIT_LIST_HEAD(&per_cpu(softirq_work_list[i], cpu)); } - register_hotcpu_notifier(&remote_softirq_cpu_notifier); - open_softirq(TASKLET_SOFTIRQ, tasklet_action); open_softirq(HI_SOFTIRQ, tasklet_hi_action); } |