linux-imx

// SPDX-License-Identifier: GPL-2.0-only

/*

 *  linux/kernel/softirq.c

 *

 *  Copyright (C) 1992 Linus Torvalds

 *

 *  Rewritten. Old one was good in 2.2, but in 2.3 it was immoral. --ANK (990903)

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/export.h>

#include <linux/kernel_stat.h>

#include <linux/interrupt.h>

#include <linux/init.h>

#include <linux/mm.h>

#include <linux/notifier.h>

#include <linux/percpu.h>

#include <linux/cpu.h>

#include <linux/freezer.h>

#include <linux/kthread.h>

#include <linux/rcupdate.h>

#include <linux/ftrace.h>

#include <linux/smp.h>

#include <linux/smpboot.h>

#include <linux/tick.h>

#include <linux/irq.h>

​

#define CREATE_TRACE_POINTS

#include <trace/events/irq.h>

​

/*

   - No shared variables, all the data are CPU local.

   - If a softirq needs serialization, let it serialize itself

     by its own spinlocks.

   - Even if softirq is serialized, only local cpu is marked for

     execution. Hence, we get something sort of weak cpu binding.

     Though it is still not clear, will it result in better locality

     or will not.

​

   Examples:

   - NET RX softirq. It is multithreaded and does not require

     any global serialization.

   - NET TX softirq. It kicks software netdevice queues, hence

     it is logically serialized per device, but this serialization

     is invisible to common code.

   - Tasklets: serialized wrt itself.

 */

​

#ifndef __ARCH_IRQ_STAT

DEFINE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);

EXPORT_PER_CPU_SYMBOL(irq_stat);

#endif

​

static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp;

​

DEFINE_PER_CPU(struct task_struct *, ksoftirqd);

​

const char * const softirq_to_name[NR_SOFTIRQS] = {

    "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "IRQ_POLL",

    "TASKLET", "SCHED", "HRTIMER", "RCU"

};

​