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Release 4.15 kernel/irq/handle.c

Directory: kernel/irq
 * linux/kernel/irq/handle.c
 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
 * This file contains the core interrupt handling code.
 * Detailed information is available in Documentation/core-api/genericirq.rst

#include <linux/irq.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>

#include <trace/events/irq.h>

#include "internals.h"

 * handle_bad_irq - handle spurious and unhandled irqs
 * @desc:      description of the interrupt
 * Handles spurious and unhandled IRQ's. It also prints a debugmessage.

void handle_bad_irq(struct irq_desc *desc) { unsigned int irq = irq_desc_get_irq(desc); print_irq_desc(irq, desc); kstat_incr_irqs_this_cpu(desc); ack_bad_irq(irq); }


Thomas Gleixner2363.89%375.00%
Yinghai Lu1336.11%125.00%

EXPORT_SYMBOL_GPL(handle_bad_irq); /* * Special, empty irq handler: */
irqreturn_t no_action(int cpl, void *dev_id) { return IRQ_NONE; }


Ingo Molnar15100.00%1100.00%

static void warn_no_thread(unsigned int irq, struct irqaction *action) { if (test_and_set_bit(IRQTF_WARNED, &action->thread_flags)) return; printk(KERN_WARNING "IRQ %d device %s returned IRQ_WAKE_THREAD " "but no thread function available.", irq, action->name); }


Thomas Gleixner41100.00%1100.00%

void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action) { /* * In case the thread crashed and was killed we just pretend that * we handled the interrupt. The hardirq handler has disabled the * device interrupt, so no irq storm is lurking. */ if (action->thread->flags & PF_EXITING) return; /* * Wake up the handler thread for this action. If the * RUNTHREAD bit is already set, nothing to do. */ if (test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) return; /* * It's safe to OR the mask lockless here. We have only two * places which write to threads_oneshot: This code and the * irq thread. * * This code is the hard irq context and can never run on two * cpus in parallel. If it ever does we have more serious * problems than this bitmask. * * The irq threads of this irq which clear their "running" bit * in threads_oneshot are serialized via desc->lock against * each other and they are serialized against this code by * IRQS_INPROGRESS. * * Hard irq handler: * * spin_lock(desc->lock); * desc->state |= IRQS_INPROGRESS; * spin_unlock(desc->lock); * set_bit(IRQTF_RUNTHREAD, &action->thread_flags); * desc->threads_oneshot |= mask; * spin_lock(desc->lock); * desc->state &= ~IRQS_INPROGRESS; * spin_unlock(desc->lock); * * irq thread: * * again: * spin_lock(desc->lock); * if (desc->state & IRQS_INPROGRESS) { * spin_unlock(desc->lock); * while(desc->state & IRQS_INPROGRESS) * cpu_relax(); * goto again; * } * if (!test_bit(IRQTF_RUNTHREAD, &action->thread_flags)) * desc->threads_oneshot &= ~mask; * spin_unlock(desc->lock); * * So either the thread waits for us to clear IRQS_INPROGRESS * or we are waiting in the flow handler for desc->lock to be * released before we reach this point. The thread also checks * IRQTF_RUNTHREAD under desc->lock. If set it leaves * threads_oneshot untouched and runs the thread another time. */ desc->threads_oneshot |= action->thread_mask; /* * We increment the threads_active counter in case we wake up * the irq thread. The irq thread decrements the counter when * it returns from the handler or in the exit path and wakes * up waiters which are stuck in synchronize_irq() when the * active count becomes zero. synchronize_irq() is serialized * against this code (hard irq handler) via IRQS_INPROGRESS * like the finalize_oneshot() code. See comment above. */ atomic_inc(&desc->threads_active); wake_up_process(action->thread); }


Thomas Gleixner4669.70%240.00%
Alexander Gordeev1116.67%240.00%
Ido Yariv913.64%120.00%

irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags) { irqreturn_t retval = IRQ_NONE; unsigned int irq = desc->irq_data.irq; struct irqaction *action; record_irq_time(desc); for_each_action_of_desc(desc, action) { irqreturn_t res; trace_irq_handler_entry(irq, action); res = action->handler(irq, action->dev_id); trace_irq_handler_exit(irq, action, res); if (WARN_ONCE(!irqs_disabled(),"irq %u handler %pF enabled interrupts\n", irq, action->handler)) local_irq_disable(); switch (res) { case IRQ_WAKE_THREAD: /* * Catch drivers which return WAKE_THREAD but * did not set up a thread function */ if (unlikely(!action->thread_fn)) { warn_no_thread(irq, action); break; } __irq_wake_thread(desc, action); /* Fall through to add to randomness */ case IRQ_HANDLED: *flags |= action->flags; break; default: break; } retval |= res; } return retval; }


Thomas Gleixner8151.27%850.00%
Ingo Molnar2817.72%16.25%
Jason Baron159.49%16.25%
Keith Busch116.96%16.25%
Daniel Lezcano116.96%212.50%
Huang Shijie63.80%16.25%
Jan Beulich53.16%16.25%
Theodore Y. Ts'o10.63%16.25%

irqreturn_t handle_irq_event_percpu(struct irq_desc *desc) { irqreturn_t retval; unsigned int flags = 0; retval = __handle_irq_event_percpu(desc, &flags); add_interrupt_randomness(desc->irq_data.irq, flags); if (!noirqdebug) note_interrupt(desc, retval); return retval; }


Keith Busch3258.18%116.67%
Thomas Gleixner1629.09%350.00%
Ingo Molnar59.09%116.67%
Theodore Y. Ts'o23.64%116.67%

irqreturn_t handle_irq_event(struct irq_desc *desc) { irqreturn_t ret; desc->istate &= ~IRQS_PENDING; irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); raw_spin_unlock(&desc->lock); ret = handle_irq_event_percpu(desc); raw_spin_lock(&desc->lock); irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); return ret; }


Thomas Gleixner66100.00%4100.00%

Overall Contributors

Thomas Gleixner28660.72%1548.39%
Ingo Molnar5712.10%13.23%
Keith Busch439.13%13.23%
Jason Baron153.18%13.23%
Yinghai Lu132.76%13.23%
Daniel Lezcano112.34%26.45%
Alexander Gordeev112.34%26.45%
Ido Yariv91.91%13.23%
Huang Shijie61.27%13.23%
Arnd Bergmann61.27%26.45%
Alexander Shiyan51.06%13.23%
Jan Beulich51.06%13.23%
Theodore Y. Ts'o30.64%13.23%
Mauro Carvalho Chehab10.21%13.23%
Directory: kernel/irq
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