diff options
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/Kconfig | 74 | ||||
| -rw-r--r-- | kernel/irq/Makefile | 7 | ||||
| -rw-r--r-- | kernel/irq/autoprobe.c | 185 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 700 | ||||
| -rw-r--r-- | kernel/irq/debug.h | 45 | ||||
| -rw-r--r-- | kernel/irq/devres.c | 94 | ||||
| -rw-r--r-- | kernel/irq/dummychip.c | 59 | ||||
| -rw-r--r-- | kernel/irq/generic-chip.c | 368 | ||||
| -rw-r--r-- | kernel/irq/handle.c | 181 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 171 | ||||
| -rw-r--r-- | kernel/irq/irqdesc.c | 466 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 1437 | ||||
| -rw-r--r-- | kernel/irq/migration.c | 81 | ||||
| -rw-r--r-- | kernel/irq/pm.c | 131 | ||||
| -rw-r--r-- | kernel/irq/proc.c | 486 | ||||
| -rw-r--r-- | kernel/irq/resend.c | 80 | ||||
| -rw-r--r-- | kernel/irq/settings.h | 142 | ||||
| -rw-r--r-- | kernel/irq/spurious.c | 364 |
18 files changed, 5071 insertions, 0 deletions
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig new file mode 100644 index 00000000..d1d051b3 --- /dev/null +++ b/kernel/irq/Kconfig @@ -0,0 +1,74 @@ +# Select this to activate the generic irq options below +config HAVE_GENERIC_HARDIRQS + bool + +if HAVE_GENERIC_HARDIRQS +menu "IRQ subsystem" +# +# Interrupt subsystem related configuration options +# +config GENERIC_HARDIRQS + def_bool y + +# Options selectable by the architecture code + +# Make sparse irq Kconfig switch below available +config HAVE_SPARSE_IRQ + bool + +# Enable the generic irq autoprobe mechanism +config GENERIC_IRQ_PROBE + bool + +# Use the generic /proc/interrupts implementation +config GENERIC_IRQ_SHOW + bool + +# Print level/edge extra information +config GENERIC_IRQ_SHOW_LEVEL + bool + +# Support for delayed migration from interrupt context +config GENERIC_PENDING_IRQ + bool + +# Alpha specific irq affinity mechanism +config AUTO_IRQ_AFFINITY + bool + +# Tasklet based software resend for pending interrupts on enable_irq() +config HARDIRQS_SW_RESEND + bool + +# Preflow handler support for fasteoi (sparc64) +config IRQ_PREFLOW_FASTEOI + bool + +# Edge style eoi based handler (cell) +config IRQ_EDGE_EOI_HANDLER + bool + +# Generic configurable interrupt chip implementation +config GENERIC_IRQ_CHIP + bool + +# Support forced irq threading +config IRQ_FORCED_THREADING + bool + +config SPARSE_IRQ + bool "Support sparse irq numbering" + depends on HAVE_SPARSE_IRQ + ---help--- + + Sparse irq numbering is useful for distro kernels that want + to define a high CONFIG_NR_CPUS value but still want to have + low kernel memory footprint on smaller machines. + + ( Sparse irqs can also be beneficial on NUMA boxes, as they spread + out the interrupt descriptors in a more NUMA-friendly way. ) + + If you don't know what to do here, say N. + +endmenu +endif diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile new file mode 100644 index 00000000..73290056 --- /dev/null +++ b/kernel/irq/Makefile @@ -0,0 +1,7 @@ + +obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o +obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o +obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o +obj-$(CONFIG_PROC_FS) += proc.o +obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o +obj-$(CONFIG_PM_SLEEP) += pm.o diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c new file mode 100644 index 00000000..0119b9d4 --- /dev/null +++ b/kernel/irq/autoprobe.c @@ -0,0 +1,185 @@ +/* + * linux/kernel/irq/autoprobe.c + * + * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar + * + * This file contains the interrupt probing code and driver APIs. + */ + +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/async.h> + +#include "internals.h" + +/* + * Autodetection depends on the fact that any interrupt that + * comes in on to an unassigned handler will get stuck with + * "IRQS_WAITING" cleared and the interrupt disabled. + */ +static DEFINE_MUTEX(probing_active); + +/** + * probe_irq_on - begin an interrupt autodetect + * + * Commence probing for an interrupt. The interrupts are scanned + * and a mask of potential interrupt lines is returned. + * + */ +unsigned long probe_irq_on(void) +{ + struct irq_desc *desc; + unsigned long mask = 0; + int i; + + /* + * quiesce the kernel, or at least the asynchronous portion + */ + async_synchronize_full(); + mutex_lock(&probing_active); + /* + * something may have generated an irq long ago and we want to + * flush such a longstanding irq before considering it as spurious. + */ + for_each_irq_desc_reverse(i, desc) { + raw_spin_lock_irq(&desc->lock); + if (!desc->action && irq_settings_can_probe(desc)) { + /* + * Some chips need to know about probing in + * progress: + */ + if (desc->irq_data.chip->irq_set_type) + desc->irq_data.chip->irq_set_type(&desc->irq_data, + IRQ_TYPE_PROBE); + irq_startup(desc, false); + } + raw_spin_unlock_irq(&desc->lock); + } + + /* Wait for longstanding interrupts to trigger. */ + msleep(20); + + /* + * enable any unassigned irqs + * (we must startup again here because if a longstanding irq + * happened in the previous stage, it may have masked itself) + */ + for_each_irq_desc_reverse(i, desc) { + raw_spin_lock_irq(&desc->lock); + if (!desc->action && irq_settings_can_probe(desc)) { + desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; + if (irq_startup(desc, false)) + desc->istate |= IRQS_PENDING; + } + raw_spin_unlock_irq(&desc->lock); + } + + /* + * Wait for spurious interrupts to trigger + */ + msleep(100); + + /* + * Now filter out any obviously spurious interrupts + */ + for_each_irq_desc(i, desc) { + raw_spin_lock_irq(&desc->lock); + + if (desc->istate & IRQS_AUTODETECT) { + /* It triggered already - consider it spurious. */ + if (!(desc->istate & IRQS_WAITING)) { + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); + } else + if (i < 32) + mask |= 1 << i; + } + raw_spin_unlock_irq(&desc->lock); + } + + return mask; +} +EXPORT_SYMBOL(probe_irq_on); + +/** + * probe_irq_mask - scan a bitmap of interrupt lines + * @val: mask of interrupts to consider + * + * Scan the interrupt lines and return a bitmap of active + * autodetect interrupts. The interrupt probe logic state + * is then returned to its previous value. + * + * Note: we need to scan all the irq's even though we will + * only return autodetect irq numbers - just so that we reset + * them all to a known state. + */ +unsigned int probe_irq_mask(unsigned long val) +{ + unsigned int mask = 0; + struct irq_desc *desc; + int i; + + for_each_irq_desc(i, desc) { + raw_spin_lock_irq(&desc->lock); + if (desc->istate & IRQS_AUTODETECT) { + if (i < 16 && !(desc->istate & IRQS_WAITING)) + mask |= 1 << i; + + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); + } + raw_spin_unlock_irq(&desc->lock); + } + mutex_unlock(&probing_active); + + return mask & val; +} +EXPORT_SYMBOL(probe_irq_mask); + +/** + * probe_irq_off - end an interrupt autodetect + * @val: mask of potential interrupts (unused) + * + * Scans the unused interrupt lines and returns the line which + * appears to have triggered the interrupt. If no interrupt was + * found then zero is returned. If more than one interrupt is + * found then minus the first candidate is returned to indicate + * their is doubt. + * + * The interrupt probe logic state is returned to its previous + * value. + * + * BUGS: When used in a module (which arguably shouldn't happen) + * nothing prevents two IRQ probe callers from overlapping. The + * results of this are non-optimal. + */ +int probe_irq_off(unsigned long val) +{ + int i, irq_found = 0, nr_of_irqs = 0; + struct irq_desc *desc; + + for_each_irq_desc(i, desc) { + raw_spin_lock_irq(&desc->lock); + + if (desc->istate & IRQS_AUTODETECT) { + if (!(desc->istate & IRQS_WAITING)) { + if (!nr_of_irqs) + irq_found = i; + nr_of_irqs++; + } + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); + } + raw_spin_unlock_irq(&desc->lock); + } + mutex_unlock(&probing_active); + + if (nr_of_irqs > 1) + irq_found = -irq_found; + + return irq_found; +} +EXPORT_SYMBOL(probe_irq_off); + diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c new file mode 100644 index 00000000..990965ec --- /dev/null +++ b/kernel/irq/chip.c @@ -0,0 +1,700 @@ +/* + * linux/kernel/irq/chip.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, for irq-chip + * based architectures. + * + * Detailed information is available in Documentation/DocBook/genericirq + */ + +#include <linux/irq.h> +#include <linux/msi.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> + +#include "internals.h" + +/** + * irq_set_chip - set the irq chip for an irq + * @irq: irq number + * @chip: pointer to irq chip description structure + */ +int irq_set_chip(unsigned int irq, struct irq_chip *chip) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + + if (!chip) + chip = &no_irq_chip; + + desc->irq_data.chip = chip; + irq_put_desc_unlock(desc, flags); + /* + * For !CONFIG_SPARSE_IRQ make the irq show up in + * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is + * already marked, and this call is harmless. + */ + irq_reserve_irq(irq); + return 0; +} +EXPORT_SYMBOL(irq_set_chip); + +/** + * irq_set_type - set the irq trigger type for an irq + * @irq: irq number + * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h + */ +int irq_set_irq_type(unsigned int irq, unsigned int type) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + int ret = 0; + + if (!desc) + return -EINVAL; + + type &= IRQ_TYPE_SENSE_MASK; + ret = __irq_set_trigger(desc, irq, type); + irq_put_desc_busunlock(desc, flags); + return ret; +} +EXPORT_SYMBOL(irq_set_irq_type); + +/** + * irq_set_handler_data - set irq handler data for an irq + * @irq: Interrupt number + * @data: Pointer to interrupt specific data + * + * Set the hardware irq controller data for an irq + */ +int irq_set_handler_data(unsigned int irq, void *data) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + desc->irq_data.handler_data = data; + irq_put_desc_unlock(desc, flags); + return 0; +} +EXPORT_SYMBOL(irq_set_handler_data); + +/** + * irq_set_msi_desc - set MSI descriptor data for an irq + * @irq: Interrupt number + * @entry: Pointer to MSI descriptor data + * + * Set the MSI descriptor entry for an irq + */ +int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + desc->irq_data.msi_desc = entry; + if (entry) + entry->irq = irq; + irq_put_desc_unlock(desc, flags); + return 0; +} + +/** + * irq_set_chip_data - set irq chip data for an irq + * @irq: Interrupt number + * @data: Pointer to chip specific data + * + * Set the hardware irq chip data for an irq + */ +int irq_set_chip_data(unsigned int irq, void *data) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + desc->irq_data.chip_data = data; + irq_put_desc_unlock(desc, flags); + return 0; +} +EXPORT_SYMBOL(irq_set_chip_data); + +struct irq_data *irq_get_irq_data(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + return desc ? &desc->irq_data : NULL; +} +EXPORT_SYMBOL_GPL(irq_get_irq_data); + +static void irq_state_clr_disabled(struct irq_desc *desc) +{ + irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED); +} + +static void irq_state_set_disabled(struct irq_desc *desc) +{ + irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); +} + +static void irq_state_clr_masked(struct irq_desc *desc) +{ + irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED); +} + +static void irq_state_set_masked(struct irq_desc *desc) +{ + irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); +} + +int irq_startup(struct irq_desc *desc, bool resend) +{ + int ret = 0; + + irq_state_clr_disabled(desc); + desc->depth = 0; + + if (desc->irq_data.chip->irq_startup) { + ret = desc->irq_data.chip->irq_startup(&desc->irq_data); + irq_state_clr_masked(desc); + } else { + irq_enable(desc); + } + if (resend) + check_irq_resend(desc, desc->irq_data.irq); + return ret; +} + +void irq_shutdown(struct irq_desc *desc) +{ + irq_state_set_disabled(desc); + desc->depth = 1; + if (desc->irq_data.chip->irq_shutdown) + desc->irq_data.chip->irq_shutdown(&desc->irq_data); + else if (desc->irq_data.chip->irq_disable) + desc->irq_data.chip->irq_disable(&desc->irq_data); + else + desc->irq_data.chip->irq_mask(&desc->irq_data); + irq_state_set_masked(desc); +} + +void irq_enable(struct irq_desc *desc) +{ + irq_state_clr_disabled(desc); + if (desc->irq_data.chip->irq_enable) + desc->irq_data.chip->irq_enable(&desc->irq_data); + else + desc->irq_data.chip->irq_unmask(&desc->irq_data); + irq_state_clr_masked(desc); +} + +void irq_disable(struct irq_desc *desc) +{ + irq_state_set_disabled(desc); + if (desc->irq_data.chip->irq_disable) { + desc->irq_data.chip->irq_disable(&desc->irq_data); + irq_state_set_masked(desc); + } +} + +static inline void mask_ack_irq(struct irq_desc *desc) +{ + if (desc->irq_data.chip->irq_mask_ack) + desc->irq_data.chip->irq_mask_ack(&desc->irq_data); + else { + desc->irq_data.chip->irq_mask(&desc->irq_data); + if (desc->irq_data.chip->irq_ack) + desc->irq_data.chip->irq_ack(&desc->irq_data); + } + irq_state_set_masked(desc); +} + +void mask_irq(struct irq_desc *desc) +{ + if (desc->irq_data.chip->irq_mask) { + desc->irq_data.chip->irq_mask(&desc->irq_data); + irq_state_set_masked(desc); + } +} + +void unmask_irq(struct irq_desc *desc) +{ + if (desc->irq_data.chip->irq_unmask) { + desc->irq_data.chip->irq_unmask(&desc->irq_data); + irq_state_clr_masked(desc); + } +} + +/* + * handle_nested_irq - Handle a nested irq from a irq thread + * @irq: the interrupt number + * + * Handle interrupts which are nested into a threaded interrupt + * handler. The handler function is called inside the calling + * threads context. + */ +void handle_nested_irq(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irqaction *action; + irqreturn_t action_ret; + + might_sleep(); + + raw_spin_lock_irq(&desc->lock); + + kstat_incr_irqs_this_cpu(irq, desc); + + action = desc->action; + if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) + goto out_unlock; + + irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); + raw_spin_unlock_irq(&desc->lock); + + action_ret = action->thread_fn(action->irq, action->dev_id); + if (!noirqdebug) + note_interrupt(irq, desc, action_ret); + + raw_spin_lock_irq(&desc->lock); + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); + +out_unlock: + raw_spin_unlock_irq(&desc->lock); +} +EXPORT_SYMBOL_GPL(handle_nested_irq); + +static bool irq_check_poll(struct irq_desc *desc) +{ + if (!(desc->istate & IRQS_POLL_INPROGRESS)) + return false; + return irq_wait_for_poll(desc); +} + +/** + * handle_simple_irq - Simple and software-decoded IRQs. + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Simple interrupts are either sent from a demultiplexing interrupt + * handler or come from hardware, where no interrupt hardware control + * is necessary. + * + * Note: The caller is expected to handle the ack, clear, mask and + * unmask issues if necessary. + */ +void +handle_simple_irq(unsigned int irq, struct irq_desc *desc) +{ + raw_spin_lock(&desc->lock); + + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out_unlock; + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + kstat_incr_irqs_this_cpu(irq, desc); + + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) + goto out_unlock; + + handle_irq_event(desc); + +out_unlock: + raw_spin_unlock(&desc->lock); +} +EXPORT_SYMBOL_GPL(handle_simple_irq); + +/* + * Called unconditionally from handle_level_irq() and only for oneshot + * interrupts from handle_fasteoi_irq() + */ +static void cond_unmask_irq(struct irq_desc *desc) +{ + /* + * We need to unmask in the following cases: + * - Standard level irq (IRQF_ONESHOT is not set) + * - Oneshot irq which did not wake the thread (caused by a + * spurious interrupt or a primary handler handling it + * completely). + */ + if (!irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) + unmask_irq(desc); +} + +/** + * handle_level_irq - Level type irq handler + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Level type interrupts are active as long as the hardware line has + * the active level. This may require to mask the interrupt and unmask + * it after the associated handler has acknowledged the device, so the + * interrupt line is back to inactive. + */ +void +handle_level_irq(unsigned int irq, struct irq_desc *desc) +{ + raw_spin_lock(&desc->lock); + mask_ack_irq(desc); + + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out_unlock; + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + kstat_incr_irqs_this_cpu(irq, desc); + + /* + * If its disabled or no action available + * keep it masked and get out of here + */ + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) + goto out_unlock; + + handle_irq_event(desc); + + cond_unmask_irq(desc); + +out_unlock: + raw_spin_unlock(&desc->lock); +} +EXPORT_SYMBOL_GPL(handle_level_irq); + +#ifdef CONFIG_IRQ_PREFLOW_FASTEOI +static inline void preflow_handler(struct irq_desc *desc) +{ + if (desc->preflow_handler) + desc->preflow_handler(&desc->irq_data); +} +#else +static inline void preflow_handler(struct irq_desc *desc) { } +#endif + +/** + * handle_fasteoi_irq - irq handler for transparent controllers + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Only a single callback will be issued to the chip: an ->eoi() + * call when the interrupt has been serviced. This enables support + * for modern forms of interrupt handlers, which handle the flow + * details in hardware, transparently. + */ +void +handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) +{ + raw_spin_lock(&desc->lock); + + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out; + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + kstat_incr_irqs_this_cpu(irq, desc); + + /* + * If its disabled or no action available + * then mask it and get out of here: + */ + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { + desc->istate |= IRQS_PENDING; + mask_irq(desc); + goto out; + } + + if (desc->istate & IRQS_ONESHOT) + mask_irq(desc); + + preflow_handler(desc); + handle_irq_event(desc); + + if (desc->istate & IRQS_ONESHOT) + cond_unmask_irq(desc); + +out_eoi: + desc->irq_data.chip->irq_eoi(&desc->irq_data); +out_unlock: + raw_spin_unlock(&desc->lock); + return; +out: + if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED)) + goto out_eoi; + goto out_unlock; +} + +/** + * handle_edge_irq - edge type IRQ handler + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Interrupt occures on the falling and/or rising edge of a hardware + * signal. The occurrence is latched into the irq controller hardware + * and must be acked in order to be reenabled. After the ack another + * interrupt can happen on the same source even before the first one + * is handled by the associated event handler. If this happens it + * might be necessary to disable (mask) the interrupt depending on the + * controller hardware. This requires to reenable the interrupt inside + * of the loop which handles the interrupts which have arrived while + * the handler was running. If all pending interrupts are handled, the + * loop is left. + */ +void +handle_edge_irq(unsigned int irq, struct irq_desc *desc) +{ + raw_spin_lock(&desc->lock); + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + /* + * If we're currently running this IRQ, or its disabled, + * we shouldn't process the IRQ. Mark it pending, handle + * the necessary masking and go out + */ + if (unlikely(irqd_irq_disabled(&desc->irq_data) || + irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (!irq_check_poll(desc)) { + desc->istate |= IRQS_PENDING; + mask_ack_irq(desc); + goto out_unlock; + } + } + kstat_incr_irqs_this_cpu(irq, desc); + + /* Start handling the irq */ + desc->irq_data.chip->irq_ack(&desc->irq_data); + + do { + if (unlikely(!desc->action)) { + mask_irq(desc); + goto out_unlock; + } + + /* + * When another irq arrived while we were handling + * one, we could have masked the irq. + * Renable it, if it was not disabled in meantime. + */ + if (unlikely(desc->istate & IRQS_PENDING)) { + if (!irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data)) + unmask_irq(desc); + } + + handle_irq_event(desc); + + } while ((desc->istate & IRQS_PENDING) && + !irqd_irq_disabled(&desc->irq_data)); + +out_unlock: + raw_spin_unlock(&desc->lock); +} + +#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER +/** + * handle_edge_eoi_irq - edge eoi type IRQ handler + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Similar as the above handle_edge_irq, but using eoi and w/o the + * mask/unmask logic. + */ +void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + + raw_spin_lock(&desc->lock); + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + /* + * If we're currently running this IRQ, or its disabled, + * we shouldn't process the IRQ. Mark it pending, handle + * the necessary masking and go out + */ + if (unlikely(irqd_irq_disabled(&desc->irq_data) || + irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (!irq_check_poll(desc)) { + desc->istate |= IRQS_PENDING; + goto out_eoi; + } + } + kstat_incr_irqs_this_cpu(irq, desc); + + do { + if (unlikely(!desc->action)) + goto out_eoi; + + handle_irq_event(desc); + + } while ((desc->istate & IRQS_PENDING) && + !irqd_irq_disabled(&desc->irq_data)); + +out_eoi: + chip->irq_eoi(&desc->irq_data); + raw_spin_unlock(&desc->lock); +} +#endif + +/** + * handle_percpu_irq - Per CPU local irq handler + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Per CPU interrupts on SMP machines without locking requirements + */ +void +handle_percpu_irq(unsigned int irq, struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + + kstat_incr_irqs_this_cpu(irq, desc); + + if (chip->irq_ack) + chip->irq_ack(&desc->irq_data); + + handle_irq_event_percpu(desc, desc->action); + + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); +} + +void +__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, + const char *name) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + + if (!desc) + return; + + if (!handle) { + handle = handle_bad_irq; + } else { + if (WARN_ON(desc->irq_data.chip == &no_irq_chip)) + goto out; + } + + /* Uninstall? */ + if (handle == handle_bad_irq) { + if (desc->irq_data.chip != &no_irq_chip) + mask_ack_irq(desc); + irq_state_set_disabled(desc); + desc->depth = 1; + } + desc->handle_irq = handle; + desc->name = name; + + if (handle != handle_bad_irq && is_chained) { + irq_settings_set_noprobe(desc); + irq_settings_set_norequest(desc); + irq_settings_set_nothread(desc); + irq_startup(desc, true); + } +out: + irq_put_desc_busunlock(desc, flags); +} +EXPORT_SYMBOL_GPL(__irq_set_handler); + +void +irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip, + irq_flow_handler_t handle, const char *name) +{ + irq_set_chip(irq, chip); + __irq_set_handler(irq, handle, 0, name); +} + +void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return; + irq_settings_clr_and_set(desc, clr, set); + + irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU | + IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT); + if (irq_settings_has_no_balance_set(desc)) + irqd_set(&desc->irq_data, IRQD_NO_BALANCING); + if (irq_settings_is_per_cpu(desc)) + irqd_set(&desc->irq_data, IRQD_PER_CPU); + if (irq_settings_can_move_pcntxt(desc)) + irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); + if (irq_settings_is_level(desc)) + irqd_set(&desc->irq_data, IRQD_LEVEL); + + irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc)); + + irq_put_desc_unlock(desc, flags); +} +EXPORT_SYMBOL_GPL(irq_modify_status); + +/** + * irq_cpu_online - Invoke all irq_cpu_online functions. + * + * Iterate through all irqs and invoke the chip.irq_cpu_online() + * for each. + */ +void irq_cpu_online(void) +{ + struct irq_desc *desc; + struct irq_chip *chip; + unsigned long flags; + unsigned int irq; + + for_each_active_irq(irq) { + desc = irq_to_desc(irq); + if (!desc) + continue; + + raw_spin_lock_irqsave(&desc->lock, flags); + + chip = irq_data_get_irq_chip(&desc->irq_data); + if (chip && chip->irq_cpu_online && + (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || + !irqd_irq_disabled(&desc->irq_data))) + chip->irq_cpu_online(&desc->irq_data); + + raw_spin_unlock_irqrestore(&desc->lock, flags); + } +} + +/** + * irq_cpu_offline - Invoke all irq_cpu_offline functions. + * + * Iterate through all irqs and invoke the chip.irq_cpu_offline() + * for each. + */ +void irq_cpu_offline(void) +{ + struct irq_desc *desc; + struct irq_chip *chip; + unsigned long flags; + unsigned int irq; + + for_each_active_irq(irq) { + desc = irq_to_desc(irq); + if (!desc) + continue; + + raw_spin_lock_irqsave(&desc->lock, flags); + + chip = irq_data_get_irq_chip(&desc->irq_data); + if (chip && chip->irq_cpu_offline && + (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || + !irqd_irq_disabled(&desc->irq_data))) + chip->irq_cpu_offline(&desc->irq_data); + + raw_spin_unlock_irqrestore(&desc->lock, flags); + } +} diff --git a/kernel/irq/debug.h b/kernel/irq/debug.h new file mode 100644 index 00000000..97a8bfad --- /dev/null +++ b/kernel/irq/debug.h @@ -0,0 +1,45 @@ +/* + * Debugging printout: + */ + +#include <linux/kallsyms.h> + +#define P(f) if (desc->status_use_accessors & f) printk("%14s set\n", #f) +#define PS(f) if (desc->istate & f) printk("%14s set\n", #f) +/* FIXME */ +#define PD(f) do { } while (0) + +static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc) +{ + printk("irq %d, desc: %p, depth: %d, count: %d, unhandled: %d\n", + irq, desc, desc->depth, desc->irq_count, desc->irqs_unhandled); + printk("->handle_irq(): %p, ", desc->handle_irq); + print_symbol("%s\n", (unsigned long)desc->handle_irq); + printk("->irq_data.chip(): %p, ", desc->irq_data.chip); + print_symbol("%s\n", (unsigned long)desc->irq_data.chip); + printk("->action(): %p\n", desc->action); + if (desc->action) { + printk("->action->handler(): %p, ", desc->action->handler); + print_symbol("%s\n", (unsigned long)desc->action->handler); + } + + P(IRQ_LEVEL); + P(IRQ_PER_CPU); + P(IRQ_NOPROBE); + P(IRQ_NOREQUEST); + P(IRQ_NOTHREAD); + P(IRQ_NOAUTOEN); + + PS(IRQS_AUTODETECT); + PS(IRQS_REPLAY); + PS(IRQS_WAITING); + PS(IRQS_PENDING); + + PD(IRQS_INPROGRESS); + PD(IRQS_DISABLED); + PD(IRQS_MASKED); +} + +#undef P +#undef PS +#undef PD diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c new file mode 100644 index 00000000..1ef4ffcd --- /dev/null +++ b/kernel/irq/devres.c @@ -0,0 +1,94 @@ +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/device.h> +#include <linux/gfp.h> + +/* + * Device resource management aware IRQ request/free implementation. + */ +struct irq_devres { + unsigned int irq; + void *dev_id; +}; + +static void devm_irq_release(struct device *dev, void *res) +{ + struct irq_devres *this = res; + + free_irq(this->irq, this->dev_id); +} + +static int devm_irq_match(struct device *dev, void *res, void *data) +{ + struct irq_devres *this = res, *match = data; + + return this->irq == match->irq && this->dev_id == match->dev_id; +} + +/** + * devm_request_threaded_irq - allocate an interrupt line for a managed device + * @dev: device to request interrupt for + * @irq: Interrupt line to allocate + * @handler: Function to be called when the IRQ occurs + * @thread_fn: function to be called in a threaded interrupt context. NULL + * for devices which handle everything in @handler + * @irqflags: Interrupt type flags + * @devname: An ascii name for the claiming device + * @dev_id: A cookie passed back to the handler function + * + * Except for the extra @dev argument, this function takes the + * same arguments and performs the same function as + * request_irq(). IRQs requested with this function will be + * automatically freed on driver detach. + * + * If an IRQ allocated with this function needs to be freed + * separately, devm_free_irq() must be used. + */ +int devm_request_threaded_irq(struct device *dev, unsigned int irq, + irq_handler_t handler, irq_handler_t thread_fn, + unsigned long irqflags, const char *devname, + void *dev_id) +{ + struct irq_devres *dr; + int rc; + + dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres), + GFP_KERNEL); + if (!dr) + return -ENOMEM; + + rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname, + dev_id); + if (rc) { + devres_free(dr); + return rc; + } + + dr->irq = irq; + dr->dev_id = dev_id; + devres_add(dev, dr); + + return 0; +} +EXPORT_SYMBOL(devm_request_threaded_irq); + +/** + * devm_free_irq - free an interrupt + * @dev: device to free interrupt for + * @irq: Interrupt line to free + * @dev_id: Device identity to free + * + * Except for the extra @dev argument, this function takes the + * same arguments and performs the same function as free_irq(). + * This function instead of free_irq() should be used to manually + * free IRQs allocated with devm_request_irq(). + */ +void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id) +{ + struct irq_devres match_data = { irq, dev_id }; + + free_irq(irq, dev_id); + WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match, + &match_data)); +} +EXPORT_SYMBOL(devm_free_irq); diff --git a/kernel/irq/dummychip.c b/kernel/irq/dummychip.c new file mode 100644 index 00000000..b5fcd96c --- /dev/null +++ b/kernel/irq/dummychip.c @@ -0,0 +1,59 @@ +/* + * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar + * Copyright (C) 2005-2006, Thomas Gleixner, Russell King + * + * This file contains the dummy interrupt chip implementation + */ +#include <linux/interrupt.h> +#include <linux/irq.h> + +#include "internals.h" + +/* + * What should we do if we get a hw irq event on an illegal vector? + * Each architecture has to answer this themself. + */ +static void ack_bad(struct irq_data *data) +{ + struct irq_desc *desc = irq_data_to_desc(data); + + print_irq_desc(data->irq, desc); + ack_bad_irq(data->irq); +} + +/* + * NOP functions + */ +static void noop(struct irq_data *data) { } + +static unsigned int noop_ret(struct irq_data *data) +{ + return 0; +} + +/* + * Generic no controller implementation + */ +struct irq_chip no_irq_chip = { + .name = "none", + .irq_startup = noop_ret, + .irq_shutdown = noop, + .irq_enable = noop, + .irq_disable = noop, + .irq_ack = ack_bad, +}; + +/* + * Generic dummy implementation which can be used for + * real dumb interrupt sources + */ +struct irq_chip dummy_irq_chip = { + .name = "dummy", + .irq_startup = noop_ret, + .irq_shutdown = noop, + .irq_enable = noop, + .irq_disable = noop, + .irq_ack = noop, + .irq_mask = noop, + .irq_unmask = noop, +}; diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c new file mode 100644 index 00000000..e38544dd --- /dev/null +++ b/kernel/irq/generic-chip.c @@ -0,0 +1,368 @@ +/* + * Library implementing the most common irq chip callback functions + * + * Copyright (C) 2011, Thomas Gleixner + */ +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/syscore_ops.h> + +#include "internals.h" + +static LIST_HEAD(gc_list); +static DEFINE_RAW_SPINLOCK(gc_lock); + +static inline struct irq_chip_regs *cur_regs(struct irq_data *d) +{ + return &container_of(d->chip, struct irq_chip_type, chip)->regs; +} + +/** + * irq_gc_noop - NOOP function + * @d: irq_data + */ +void irq_gc_noop(struct irq_data *d) +{ +} + +/** + * irq_gc_mask_disable_reg - Mask chip via disable register + * @d: irq_data + * + * Chip has separate enable/disable registers instead of a single mask + * register. + */ +void irq_gc_mask_disable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->disable); + gc->mask_cache &= ~mask; + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_set_mask_bit - Mask chip via setting bit in mask register + * @d: irq_data + * + * Chip has a single mask register. Values of this register are cached + * and protected by gc->lock + */ +void irq_gc_mask_set_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + gc->mask_cache |= mask; + irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask); + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_set_mask_bit - Mask chip via clearing bit in mask register + * @d: irq_data + * + * Chip has a single mask register. Values of this register are cached + * and protected by gc->lock + */ +void irq_gc_mask_clr_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + gc->mask_cache &= ~mask; + irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask); + irq_gc_unlock(gc); +} + +/** + * irq_gc_unmask_enable_reg - Unmask chip via enable register + * @d: irq_data + * + * Chip has separate enable/disable registers instead of a single mask + * register. + */ +void irq_gc_unmask_enable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->enable); + gc->mask_cache |= mask; + irq_gc_unlock(gc); +} + +/** + * irq_gc_ack_set_bit - Ack pending interrupt via setting bit + * @d: irq_data + */ +void irq_gc_ack_set_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack); + irq_gc_unlock(gc); +} + +/** + * irq_gc_ack_clr_bit - Ack pending interrupt via clearing bit + * @d: irq_data + */ +void irq_gc_ack_clr_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = ~(1 << (d->irq - gc->irq_base)); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack); + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_disable_reg_and_ack- Mask and ack pending interrupt + * @d: irq_data + */ +void irq_gc_mask_disable_reg_and_ack(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->mask); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack); + irq_gc_unlock(gc); +} + +/** + * irq_gc_eoi - EOI interrupt + * @d: irq_data + */ +void irq_gc_eoi(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->eoi); + irq_gc_unlock(gc); +} + +/** + * irq_gc_set_wake - Set/clr wake bit for an interrupt + * @d: irq_data + * + * For chips where the wake from suspend functionality is not + * configured in a separate register and the wakeup active state is + * just stored in a bitmask. + */ +int irq_gc_set_wake(struct irq_data *d, unsigned int on) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + if (!(mask & gc->wake_enabled)) + return -EINVAL; + + irq_gc_lock(gc); + if (on) + gc->wake_active |= mask; + else + gc->wake_active &= ~mask; + irq_gc_unlock(gc); + return 0; +} + +/** + * irq_alloc_generic_chip - Allocate a generic chip and initialize it + * @name: Name of the irq chip + * @num_ct: Number of irq_chip_type instances associated with this + * @irq_base: Interrupt base nr for this chip + * @reg_base: Register base address (virtual) + * @handler: Default flow handler associated with this chip + * + * Returns an initialized irq_chip_generic structure. The chip defaults + * to the primary (index 0) irq_chip_type and @handler + */ +struct irq_chip_generic * +irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base, + void __iomem *reg_base, irq_flow_handler_t handler) +{ + struct irq_chip_generic *gc; + unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type); + + gc = kzalloc(sz, GFP_KERNEL); + if (gc) { + raw_spin_lock_init(&gc->lock); + gc->num_ct = num_ct; + gc->irq_base = irq_base; + gc->reg_base = reg_base; + gc->chip_types->chip.name = name; + gc->chip_types->handler = handler; + } + return gc; +} + +/* + * Separate lockdep class for interrupt chip which can nest irq_desc + * lock. + */ +static struct lock_class_key irq_nested_lock_class; + +/** + * irq_setup_generic_chip - Setup a range of interrupts with a generic chip + * @gc: Generic irq chip holding all data + * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base + * @flags: Flags for initialization + * @clr: IRQ_* bits to clear + * @set: IRQ_* bits to set + * + * Set up max. 32 interrupts starting from gc->irq_base. Note, this + * initializes all interrupts to the primary irq_chip_type and its + * associated handler. + */ +void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk, + enum irq_gc_flags flags, unsigned int clr, + unsigned int set) +{ + struct irq_chip_type *ct = gc->chip_types; + unsigned int i; + + raw_spin_lock(&gc_lock); + list_add_tail(&gc->list, &gc_list); + raw_spin_unlock(&gc_lock); + + /* Init mask cache ? */ + if (flags & IRQ_GC_INIT_MASK_CACHE) + gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask); + + for (i = gc->irq_base; msk; msk >>= 1, i++) { + if (!(msk & 0x01)) + continue; + + if (flags & IRQ_GC_INIT_NESTED_LOCK) + irq_set_lockdep_class(i, &irq_nested_lock_class); + + irq_set_chip_and_handler(i, &ct->chip, ct->handler); + irq_set_chip_data(i, gc); + irq_modify_status(i, clr, set); + } + gc->irq_cnt = i - gc->irq_base; +} + +/** + * irq_setup_alt_chip - Switch to alternative chip + * @d: irq_data for this interrupt + * @type Flow type to be initialized + * + * Only to be called from chip->irq_set_type() callbacks. + */ +int irq_setup_alt_chip(struct irq_data *d, unsigned int type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = gc->chip_types; + unsigned int i; + + for (i = 0; i < gc->num_ct; i++, ct++) { + if (ct->type & type) { + d->chip = &ct->chip; + irq_data_to_desc(d)->handle_irq = ct->handler; + return 0; + } + } + return -EINVAL; +} + +/** + * irq_remove_generic_chip - Remove a chip + * @gc: Generic irq chip holding all data + * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base + * @clr: IRQ_* bits to clear + * @set: IRQ_* bits to set + * + * Remove up to 32 interrupts starting from gc->irq_base. + */ +void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk, + unsigned int clr, unsigned int set) +{ + unsigned int i = gc->irq_base; + + raw_spin_lock(&gc_lock); + list_del(&gc->list); + raw_spin_unlock(&gc_lock); + + for (; msk; msk >>= 1, i++) { + if (!(msk & 0x01)) + continue; + + /* Remove handler first. That will mask the irq line */ + irq_set_handler(i, NULL); + irq_set_chip(i, &no_irq_chip); + irq_set_chip_data(i, NULL); + irq_modify_status(i, clr, set); + } +} + +#ifdef CONFIG_PM +static int irq_gc_suspend(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_suspend) + ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base)); + } + return 0; +} + +static void irq_gc_resume(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_resume) + ct->chip.irq_resume(irq_get_irq_data(gc->irq_base)); + } +} +#else +#define irq_gc_suspend NULL +#define irq_gc_resume NULL +#endif + +static void irq_gc_shutdown(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_pm_shutdown) + ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base)); + } +} + +static struct syscore_ops irq_gc_syscore_ops = { + .suspend = irq_gc_suspend, + .resume = irq_gc_resume, + .shutdown = irq_gc_shutdown, +}; + +static int __init irq_gc_init_ops(void) +{ + register_syscore_ops(&irq_gc_syscore_ops); + return 0; +} +device_initcall(irq_gc_init_ops); diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c new file mode 100644 index 00000000..470d08c8 --- /dev/null +++ b/kernel/irq/handle.c @@ -0,0 +1,181 @@ +/* + * 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/DocBook/genericirq + * + */ + +#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 + * @irq: the interrupt number + * @desc: description of the interrupt + * + * Handles spurious and unhandled IRQ's. It also prints a debugmessage. + */ +void handle_bad_irq(unsigned int irq, struct irq_desc *desc) +{ + print_irq_desc(irq, desc); + kstat_incr_irqs_this_cpu(irq, desc); + ack_bad_irq(irq); +} + +/* + * Special, empty irq handler: + */ +irqreturn_t no_action(int cpl, void *dev_id) +{ + return IRQ_NONE; +} + +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); +} + +static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action) +{ + /* + * Wake up the handler thread for this 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 the + * RUNTHREAD bit is already set, nothing to do. + */ + if (test_bit(IRQTF_DIED, &action->thread_flags) || + 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; + wake_up_process(action->thread); +} + +irqreturn_t +handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) +{ + irqreturn_t retval = IRQ_NONE; + unsigned int random = 0, irq = desc->irq_data.irq; + + do { + 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: + random |= action->flags; + break; + + default: + break; + } + + retval |= res; + action = action->next; + } while (action); + + if (random & IRQF_SAMPLE_RANDOM) + add_interrupt_randomness(irq); + + if (!noirqdebug) + note_interrupt(irq, desc, retval); + return retval; +} + +irqreturn_t handle_irq_event(struct irq_desc *desc) +{ + struct irqaction *action = desc->action; + 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, action); + + raw_spin_lock(&desc->lock); + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); + return ret; +} diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h new file mode 100644 index 00000000..62efdc44 --- /dev/null +++ b/kernel/irq/internals.h @@ -0,0 +1,171 @@ +/* + * IRQ subsystem internal functions and variables: + * + * Do not ever include this file from anything else than + * kernel/irq/. Do not even think about using any information outside + * of this file for your non core code. + */ +#include <linux/irqdesc.h> + +#ifdef CONFIG_SPARSE_IRQ +# define IRQ_BITMAP_BITS (NR_IRQS + 8196) +#else +# define IRQ_BITMAP_BITS NR_IRQS +#endif + +#define istate core_internal_state__do_not_mess_with_it + +extern int noirqdebug; + +/* + * Bits used by threaded handlers: + * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run + * IRQTF_DIED - handler thread died + * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed + * IRQTF_AFFINITY - irq thread is requested to adjust affinity + * IRQTF_FORCED_THREAD - irq action is force threaded + */ +enum { + IRQTF_RUNTHREAD, + IRQTF_DIED, + IRQTF_WARNED, + IRQTF_AFFINITY, + IRQTF_FORCED_THREAD, +}; + +/* + * Bit masks for desc->state + * + * IRQS_AUTODETECT - autodetection in progress + * IRQS_SPURIOUS_DISABLED - was disabled due to spurious interrupt + * detection + * IRQS_POLL_INPROGRESS - polling in progress + * IRQS_ONESHOT - irq is not unmasked in primary handler + * IRQS_REPLAY - irq is replayed + * IRQS_WAITING - irq is waiting + * IRQS_PENDING - irq is pending and replayed later + * IRQS_SUSPENDED - irq is suspended + */ +enum { + IRQS_AUTODETECT = 0x00000001, + IRQS_SPURIOUS_DISABLED = 0x00000002, + IRQS_POLL_INPROGRESS = 0x00000008, + IRQS_ONESHOT = 0x00000020, + IRQS_REPLAY = 0x00000040, + IRQS_WAITING = 0x00000080, + IRQS_PENDING = 0x00000200, + IRQS_SUSPENDED = 0x00000800, +}; + +#include "debug.h" +#include "settings.h" + +#define irq_data_to_desc(data) container_of(data, struct irq_desc, irq_data) + +extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, + unsigned long flags); +extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp); +extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume); + +extern int irq_startup(struct irq_desc *desc, bool resend); +extern void irq_shutdown(struct irq_desc *desc); +extern void irq_enable(struct irq_desc *desc); +extern void irq_disable(struct irq_desc *desc); +extern void mask_irq(struct irq_desc *desc); +extern void unmask_irq(struct irq_desc *desc); + +extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr); + +irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action); +irqreturn_t handle_irq_event(struct irq_desc *desc); + +/* Resending of interrupts :*/ +void check_irq_resend(struct irq_desc *desc, unsigned int irq); +bool irq_wait_for_poll(struct irq_desc *desc); + +#ifdef CONFIG_PROC_FS +extern void register_irq_proc(unsigned int irq, struct irq_desc *desc); +extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc); +extern void register_handler_proc(unsigned int irq, struct irqaction *action); +extern void unregister_handler_proc(unsigned int irq, struct irqaction *action); +#else +static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { } +static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { } +static inline void register_handler_proc(unsigned int irq, + struct irqaction *action) { } +static inline void unregister_handler_proc(unsigned int irq, + struct irqaction *action) { } +#endif + +extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask); + +extern void irq_set_thread_affinity(struct irq_desc *desc); + +/* Inline functions for support of irq chips on slow busses */ +static inline void chip_bus_lock(struct irq_desc *desc) +{ + if (unlikely(desc->irq_data.chip->irq_bus_lock)) + desc->irq_data.chip->irq_bus_lock(&desc->irq_data); +} + +static inline void chip_bus_sync_unlock(struct irq_desc *desc) +{ + if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock)) + desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data); +} + +struct irq_desc * +__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus); +void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus); + +static inline struct irq_desc * +irq_get_desc_buslock(unsigned int irq, unsigned long *flags) +{ + return __irq_get_desc_lock(irq, flags, true); +} + +static inline void +irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags) +{ + __irq_put_desc_unlock(desc, flags, true); +} + +static inline struct irq_desc * +irq_get_desc_lock(unsigned int irq, unsigned long *flags) +{ + return __irq_get_desc_lock(irq, flags, false); +} + +static inline void +irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags) +{ + __irq_put_desc_unlock(desc, flags, false); +} + +/* + * Manipulation functions for irq_data.state + */ +static inline void irqd_set_move_pending(struct irq_data *d) +{ + d->state_use_accessors |= IRQD_SETAFFINITY_PENDING; +} + +static inline void irqd_clr_move_pending(struct irq_data *d) +{ + d->state_use_accessors &= ~IRQD_SETAFFINITY_PENDING; +} + +static inline void irqd_clear(struct irq_data *d, unsigned int mask) +{ + d->state_use_accessors &= ~mask; +} + +static inline void irqd_set(struct irq_data *d, unsigned int mask) +{ + d->state_use_accessors |= mask; +} + +static inline bool irqd_has_set(struct irq_data *d, unsigned int mask) +{ + return d->state_use_accessors & mask; +} diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c new file mode 100644 index 00000000..4c60a50e --- /dev/null +++ b/kernel/irq/irqdesc.c @@ -0,0 +1,466 @@ +/* + * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar + * Copyright (C) 2005-2006, Thomas Gleixner, Russell King + * + * This file contains the interrupt descriptor management code + * + * Detailed information is available in Documentation/DocBook/genericirq + * + */ +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/radix-tree.h> +#include <linux/bitmap.h> + +#include "internals.h" + +/* + * lockdep: we want to handle all irq_desc locks as a single lock-class: + */ +static struct lock_class_key irq_desc_lock_class; + +#if defined(CONFIG_SMP) +static void __init init_irq_default_affinity(void) +{ + alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); + cpumask_setall(irq_default_affinity); +} +#else +static void __init init_irq_default_affinity(void) +{ +} +#endif + +#ifdef CONFIG_SMP +static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) +{ + if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node)) + return -ENOMEM; + +#ifdef CONFIG_GENERIC_PENDING_IRQ + if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) { + free_cpumask_var(desc->irq_data.affinity); + return -ENOMEM; + } +#endif + return 0; +} + +static void desc_smp_init(struct irq_desc *desc, int node) +{ + desc->irq_data.node = node; + cpumask_copy(desc->irq_data.affinity, irq_default_affinity); +#ifdef CONFIG_GENERIC_PENDING_IRQ + cpumask_clear(desc->pending_mask); +#endif +} + +static inline int desc_node(struct irq_desc *desc) +{ + return desc->irq_data.node; +} + +#else +static inline int +alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; } +static inline void desc_smp_init(struct irq_desc *desc, int node) { } +static inline int desc_node(struct irq_desc *desc) { return 0; } +#endif + +static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node) +{ + int cpu; + + desc->irq_data.irq = irq; + desc->irq_data.chip = &no_irq_chip; + desc->irq_data.chip_data = NULL; + desc->irq_data.handler_data = NULL; + desc->irq_data.msi_desc = NULL; + irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS); + irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); + desc->handle_irq = handle_bad_irq; + desc->depth = 1; + desc->irq_count = 0; + desc->irqs_unhandled = 0; + desc->name = NULL; + for_each_possible_cpu(cpu) + *per_cpu_ptr(desc->kstat_irqs, cpu) = 0; + desc_smp_init(desc, node); +} + +int nr_irqs = NR_IRQS; +EXPORT_SYMBOL_GPL(nr_irqs); + +static DEFINE_MUTEX(sparse_irq_lock); +static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS); + +#ifdef CONFIG_SPARSE_IRQ + +static RADIX_TREE(irq_desc_tree, GFP_KERNEL); + +static void irq_insert_desc(unsigned int irq, struct irq_desc *desc) +{ + radix_tree_insert(&irq_desc_tree, irq, desc); +} + +struct irq_desc *irq_to_desc(unsigned int irq) +{ + return radix_tree_lookup(&irq_desc_tree, irq); +} + +static void delete_irq_desc(unsigned int irq) +{ + radix_tree_delete(&irq_desc_tree, irq); +} + +#ifdef CONFIG_SMP +static void free_masks(struct irq_desc *desc) +{ +#ifdef CONFIG_GENERIC_PENDING_IRQ + free_cpumask_var(desc->pending_mask); +#endif + free_cpumask_var(desc->irq_data.affinity); +} +#else +static inline void free_masks(struct irq_desc *desc) { } +#endif + +static struct irq_desc *alloc_desc(int irq, int node) +{ + struct irq_desc *desc; + gfp_t gfp = GFP_KERNEL; + + desc = kzalloc_node(sizeof(*desc), gfp, node); + if (!desc) + return NULL; + /* allocate based on nr_cpu_ids */ + desc->kstat_irqs = alloc_percpu(unsigned int); + if (!desc->kstat_irqs) + goto err_desc; + + if (alloc_masks(desc, gfp, node)) + goto err_kstat; + + raw_spin_lock_init(&desc->lock); + lockdep_set_class(&desc->lock, &irq_desc_lock_class); + + desc_set_defaults(irq, desc, node); + + return desc; + +err_kstat: + free_percpu(desc->kstat_irqs); +err_desc: + kfree(desc); + return NULL; +} + +static void free_desc(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + unregister_irq_proc(irq, desc); + + mutex_lock(&sparse_irq_lock); + delete_irq_desc(irq); + mutex_unlock(&sparse_irq_lock); + + free_masks(desc); + free_percpu(desc->kstat_irqs); + kfree(desc); +} + +static int alloc_descs(unsigned int start, unsigned int cnt, int node) +{ + struct irq_desc *desc; + int i; + + for (i = 0; i < cnt; i++) { + desc = alloc_desc(start + i, node); + if (!desc) + goto err; + mutex_lock(&sparse_irq_lock); + irq_insert_desc(start + i, desc); + mutex_unlock(&sparse_irq_lock); + } + return start; + +err: + for (i--; i >= 0; i--) + free_desc(start + i); + + mutex_lock(&sparse_irq_lock); + bitmap_clear(allocated_irqs, start, cnt); + mutex_unlock(&sparse_irq_lock); + return -ENOMEM; +} + +static int irq_expand_nr_irqs(unsigned int nr) +{ + if (nr > IRQ_BITMAP_BITS) + return -ENOMEM; + nr_irqs = nr; + return 0; +} + +int __init early_irq_init(void) +{ + int i, initcnt, node = first_online_node; + struct irq_desc *desc; + + init_irq_default_affinity(); + + /* Let arch update nr_irqs and return the nr of preallocated irqs */ + initcnt = arch_probe_nr_irqs(); + printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt); + + if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS)) + nr_irqs = IRQ_BITMAP_BITS; + + if (WARN_ON(initcnt > IRQ_BITMAP_BITS)) + initcnt = IRQ_BITMAP_BITS; + + if (initcnt > nr_irqs) + nr_irqs = initcnt; + + for (i = 0; i < initcnt; i++) { + desc = alloc_desc(i, node); + set_bit(i, allocated_irqs); + irq_insert_desc(i, desc); + } + return arch_early_irq_init(); +} + +#else /* !CONFIG_SPARSE_IRQ */ + +struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = { + [0 ... NR_IRQS-1] = { + .handle_irq = handle_bad_irq, + .depth = 1, + .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock), + } +}; + +int __init early_irq_init(void) +{ + int count, i, node = first_online_node; + struct irq_desc *desc; + + init_irq_default_affinity(); + + printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS); + + desc = irq_desc; + count = ARRAY_SIZE(irq_desc); + + for (i = 0; i < count; i++) { + desc[i].kstat_irqs = alloc_percpu(unsigned int); + alloc_masks(&desc[i], GFP_KERNEL, node); + raw_spin_lock_init(&desc[i].lock); + lockdep_set_class(&desc[i].lock, &irq_desc_lock_class); + desc_set_defaults(i, &desc[i], node); + } + return arch_early_irq_init(); +} + +struct irq_desc *irq_to_desc(unsigned int irq) +{ + return (irq < NR_IRQS) ? irq_desc + irq : NULL; +} + +static void free_desc(unsigned int irq) +{ + dynamic_irq_cleanup(irq); +} + +static inline int alloc_descs(unsigned int start, unsigned int cnt, int node) +{ + return start; +} + +static int irq_expand_nr_irqs(unsigned int nr) +{ + return -ENOMEM; +} + +#endif /* !CONFIG_SPARSE_IRQ */ + +/** + * generic_handle_irq - Invoke the handler for a particular irq + * @irq: The irq number to handle + * + */ +int generic_handle_irq(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc) + return -EINVAL; + generic_handle_irq_desc(irq, desc); + return 0; +} +EXPORT_SYMBOL_GPL(generic_handle_irq); + +/* Dynamic interrupt handling */ + +/** + * irq_free_descs - free irq descriptors + * @from: Start of descriptor range + * @cnt: Number of consecutive irqs to free + */ +void irq_free_descs(unsigned int from, unsigned int cnt) +{ + int i; + + if (from >= nr_irqs || (from + cnt) > nr_irqs) + return; + + for (i = 0; i < cnt; i++) + free_desc(from + i); + + mutex_lock(&sparse_irq_lock); + bitmap_clear(allocated_irqs, from, cnt); + mutex_unlock(&sparse_irq_lock); +} +EXPORT_SYMBOL_GPL(irq_free_descs); + +/** + * irq_alloc_descs - allocate and initialize a range of irq descriptors + * @irq: Allocate for specific irq number if irq >= 0 + * @from: Start the search from this irq number + * @cnt: Number of consecutive irqs to allocate. + * @node: Preferred node on which the irq descriptor should be allocated + * + * Returns the first irq number or error code + */ +int __ref +irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node) +{ + int start, ret; + + if (!cnt) + return -EINVAL; + + if (irq >= 0) { + if (from > irq) + return -EINVAL; + from = irq; + } + + mutex_lock(&sparse_irq_lock); + + start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS, + from, cnt, 0); + ret = -EEXIST; + if (irq >=0 && start != irq) + goto err; + + if (start + cnt > nr_irqs) { + ret = irq_expand_nr_irqs(start + cnt); + if (ret) + goto err; + } + + bitmap_set(allocated_irqs, start, cnt); + mutex_unlock(&sparse_irq_lock); + return alloc_descs(start, cnt, node); + +err: + mutex_unlock(&sparse_irq_lock); + return ret; +} +EXPORT_SYMBOL_GPL(irq_alloc_descs); + +/** + * irq_reserve_irqs - mark irqs allocated + * @from: mark from irq number + * @cnt: number of irqs to mark + * + * Returns 0 on success or an appropriate error code + */ +int irq_reserve_irqs(unsigned int from, unsigned int cnt) +{ + unsigned int start; + int ret = 0; + + if (!cnt || (from + cnt) > nr_irqs) + return -EINVAL; + + mutex_lock(&sparse_irq_lock); + start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0); + if (start == from) + bitmap_set(allocated_irqs, start, cnt); + else + ret = -EEXIST; + mutex_unlock(&sparse_irq_lock); + return ret; +} + +/** + * irq_get_next_irq - get next allocated irq number + * @offset: where to start the search + * + * Returns next irq number after offset or nr_irqs if none is found. + */ +unsigned int irq_get_next_irq(unsigned int offset) +{ + return find_next_bit(allocated_irqs, nr_irqs, offset); +} + +struct irq_desc * +__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (desc) { + if (bus) + chip_bus_lock(desc); + raw_spin_lock_irqsave(&desc->lock, *flags); + } + return desc; +} + +void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus) +{ + raw_spin_unlock_irqrestore(&desc->lock, flags); + if (bus) + chip_bus_sync_unlock(desc); +} + +/** + * dynamic_irq_cleanup - cleanup a dynamically allocated irq + * @irq: irq number to initialize + */ +void dynamic_irq_cleanup(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + + raw_spin_lock_irqsave(&desc->lock, flags); + desc_set_defaults(irq, desc, desc_node(desc)); + raw_spin_unlock_irqrestore(&desc->lock, flags); +} + +unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) +{ + struct irq_desc *desc = irq_to_desc(irq); + + return desc && desc->kstat_irqs ? + *per_cpu_ptr(desc->kstat_irqs, cpu) : 0; +} + +unsigned int kstat_irqs(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + int cpu; + int sum = 0; + + if (!desc || !desc->kstat_irqs) + return 0; + for_each_possible_cpu(cpu) + sum += *per_cpu_ptr(desc->kstat_irqs, cpu); + return sum; +} diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c new file mode 100644 index 00000000..df8136ff --- /dev/null +++ b/kernel/irq/manage.c @@ -0,0 +1,1437 @@ +/* + * linux/kernel/irq/manage.c + * + * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar + * Copyright (C) 2005-2006 Thomas Gleixner + * + * This file contains driver APIs to the irq subsystem. + */ + +#include <linux/irq.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/sched.h> + +#include "internals.h" + +#ifdef CONFIG_IRQ_FORCED_THREADING +__read_mostly bool force_irqthreads; + +static int __init setup_forced_irqthreads(char *arg) +{ + force_irqthreads = true; + return 0; +} +early_param("threadirqs", setup_forced_irqthreads); +#endif + +/** + * synchronize_irq - wait for pending IRQ handlers (on other CPUs) + * @irq: interrupt number to wait for + * + * This function waits for any pending IRQ handlers for this interrupt + * to complete before returning. If you use this function while + * holding a resource the IRQ handler may need you will deadlock. + * + * This function may be called - with care - from IRQ context. + */ +void synchronize_irq(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + bool inprogress; + + if (!desc) + return; + + do { + unsigned long flags; + + /* + * Wait until we're out of the critical section. This might + * give the wrong answer due to the lack of memory barriers. + */ + while (irqd_irq_inprogress(&desc->irq_data)) + cpu_relax(); + + /* Ok, that indicated we're done: double-check carefully. */ + raw_spin_lock_irqsave(&desc->lock, flags); + inprogress = irqd_irq_inprogress(&desc->irq_data); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + /* Oops, that failed? */ + } while (inprogress); + + /* + * We made sure that no hardirq handler is running. Now verify + * that no threaded handlers are active. + */ + wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active)); +} +EXPORT_SYMBOL(synchronize_irq); + +#ifdef CONFIG_SMP +cpumask_var_t irq_default_affinity; + +/** + * irq_can_set_affinity - Check if the affinity of a given irq can be set + * @irq: Interrupt to check + * + */ +int irq_can_set_affinity(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc || !irqd_can_balance(&desc->irq_data) || + !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) + return 0; + + return 1; +} + +/** + * irq_set_thread_affinity - Notify irq threads to adjust affinity + * @desc: irq descriptor which has affitnity changed + * + * We just set IRQTF_AFFINITY and delegate the affinity setting + * to the interrupt thread itself. We can not call + * set_cpus_allowed_ptr() here as we hold desc->lock and this + * code can be called from hard interrupt context. + */ +void irq_set_thread_affinity(struct irq_desc *desc) +{ + struct irqaction *action = desc->action; + + while (action) { + if (action->thread) + set_bit(IRQTF_AFFINITY, &action->thread_flags); + action = action->next; + } +} + +#ifdef CONFIG_GENERIC_PENDING_IRQ +static inline bool irq_can_move_pcntxt(struct irq_data *data) +{ + return irqd_can_move_in_process_context(data); +} +static inline bool irq_move_pending(struct irq_data *data) +{ + return irqd_is_setaffinity_pending(data); +} +static inline void +irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) +{ + cpumask_copy(desc->pending_mask, mask); +} +static inline void +irq_get_pending(struct cpumask *mask, struct irq_desc *desc) +{ + cpumask_copy(mask, desc->pending_mask); +} +#else +static inline bool irq_can_move_pcntxt(struct irq_data *data) { return true; } +static inline bool irq_move_pending(struct irq_data *data) { return false; } +static inline void +irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) { } +static inline void +irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { } +#endif + +int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) +{ + struct irq_chip *chip = irq_data_get_irq_chip(data); + struct irq_desc *desc = irq_data_to_desc(data); + int ret = 0; + + if (!chip || !chip->irq_set_affinity) + return -EINVAL; + + if (irq_can_move_pcntxt(data)) { + ret = chip->irq_set_affinity(data, mask, false); + switch (ret) { + case IRQ_SET_MASK_OK: + cpumask_copy(data->affinity, mask); + case IRQ_SET_MASK_OK_NOCOPY: + irq_set_thread_affinity(desc); + ret = 0; + } + } else { + irqd_set_move_pending(data); + irq_copy_pending(desc, mask); + } + + if (desc->affinity_notify) { + kref_get(&desc->affinity_notify->kref); + schedule_work(&desc->affinity_notify->work); + } + irqd_set(data, IRQD_AFFINITY_SET); + + return ret; +} + +/** + * irq_set_affinity - Set the irq affinity of a given irq + * @irq: Interrupt to set affinity + * @mask: cpumask + * + */ +int irq_set_affinity(unsigned int irq, const struct cpumask *mask) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + int ret; + + if (!desc) + return -EINVAL; + + raw_spin_lock_irqsave(&desc->lock, flags); + ret = __irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask); + raw_spin_unlock_irqrestore(&desc->lock, flags); + return ret; +} + +int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + desc->affinity_hint = m; + irq_put_desc_unlock(desc, flags); + return 0; +} +EXPORT_SYMBOL_GPL(irq_set_affinity_hint); + +static void irq_affinity_notify(struct work_struct *work) +{ + struct irq_affinity_notify *notify = + container_of(work, struct irq_affinity_notify, work); + struct irq_desc *desc = irq_to_desc(notify->irq); + cpumask_var_t cpumask; + unsigned long flags; + + if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL)) + goto out; + + raw_spin_lock_irqsave(&desc->lock, flags); + if (irq_move_pending(&desc->irq_data)) + irq_get_pending(cpumask, desc); + else + cpumask_copy(cpumask, desc->irq_data.affinity); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + notify->notify(notify, cpumask); + + free_cpumask_var(cpumask); +out: + kref_put(¬ify->kref, notify->release); +} + +/** + * irq_set_affinity_notifier - control notification of IRQ affinity changes + * @irq: Interrupt for which to enable/disable notification + * @notify: Context for notification, or %NULL to disable + * notification. Function pointers must be initialised; + * the other fields will be initialised by this function. + * + * Must be called in process context. Notification may only be enabled + * after the IRQ is allocated and must be disabled before the IRQ is + * freed using free_irq(). + */ +int +irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irq_affinity_notify *old_notify; + unsigned long flags; + + /* The release function is promised process context */ + might_sleep(); + + if (!desc) + return -EINVAL; + + /* Complete initialisation of *notify */ + if (notify) { + notify->irq = irq; + kref_init(¬ify->kref); + INIT_WORK(¬ify->work, irq_affinity_notify); + } + + raw_spin_lock_irqsave(&desc->lock, flags); + old_notify = desc->affinity_notify; + desc->affinity_notify = notify; + raw_spin_unlock_irqrestore(&desc->lock, flags); + + if (old_notify) + kref_put(&old_notify->kref, old_notify->release); + + return 0; +} +EXPORT_SYMBOL_GPL(irq_set_affinity_notifier); + +#ifndef CONFIG_AUTO_IRQ_AFFINITY +/* + * Generic version of the affinity autoselector. + */ +static int +setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + struct cpumask *set = irq_default_affinity; + int ret; + + /* Excludes PER_CPU and NO_BALANCE interrupts */ + if (!irq_can_set_affinity(irq)) + return 0; + + /* + * Preserve an userspace affinity setup, but make sure that + * one of the targets is online. + */ + if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) { + if (cpumask_intersects(desc->irq_data.affinity, + cpu_online_mask)) + set = desc->irq_data.affinity; + else + irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET); + } + + cpumask_and(mask, cpu_online_mask, set); + ret = chip->irq_set_affinity(&desc->irq_data, mask, false); + switch (ret) { + case IRQ_SET_MASK_OK: + cpumask_copy(desc->irq_data.affinity, mask); + case IRQ_SET_MASK_OK_NOCOPY: + irq_set_thread_affinity(desc); + } + return 0; +} +#else +static inline int +setup_affinity(unsigned int irq, struct irq_desc *d, struct cpumask *mask) +{ + return irq_select_affinity(irq); +} +#endif + +/* + * Called when affinity is set via /proc/irq + */ +int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + int ret; + + raw_spin_lock_irqsave(&desc->lock, flags); + ret = setup_affinity(irq, desc, mask); + raw_spin_unlock_irqrestore(&desc->lock, flags); + return ret; +} + +#else +static inline int +setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) +{ + return 0; +} +#endif + +void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend) +{ + if (suspend) { + if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND)) + return; + desc->istate |= IRQS_SUSPENDED; + } + + if (!desc->depth++) + irq_disable(desc); +} + +static int __disable_irq_nosync(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + + if (!desc) + return -EINVAL; + __disable_irq(desc, irq, false); + irq_put_desc_busunlock(desc, flags); + return 0; +} + +/** + * disable_irq_nosync - disable an irq without waiting + * @irq: Interrupt to disable + * + * Disable the selected interrupt line. Disables and Enables are + * nested. + * Unlike disable_irq(), this function does not ensure existing + * instances of the IRQ handler have completed before returning. + * + * This function may be called from IRQ context. + */ +void disable_irq_nosync(unsigned int irq) +{ + __disable_irq_nosync(irq); +} +EXPORT_SYMBOL(disable_irq_nosync); + +/** + * disable_irq - disable an irq and wait for completion + * @irq: Interrupt to disable + * + * Disable the selected interrupt line. Enables and Disables are + * nested. + * This function waits for any pending IRQ handlers for this interrupt + * to complete before returning. If you use this function while + * holding a resource the IRQ handler may need you will deadlock. + * + * This function may be called - with care - from IRQ context. + */ +void disable_irq(unsigned int irq) +{ + if (!__disable_irq_nosync(irq)) + synchronize_irq(irq); +} +EXPORT_SYMBOL(disable_irq); + +void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) +{ + if (resume) { + if (!(desc->istate & IRQS_SUSPENDED)) { + if (!desc->action) + return; + if (!(desc->action->flags & IRQF_FORCE_RESUME)) + return; + /* Pretend that it got disabled ! */ + desc->depth++; + } + desc->istate &= ~IRQS_SUSPENDED; + } + + switch (desc->depth) { + case 0: + err_out: + WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq); + break; + case 1: { + if (desc->istate & IRQS_SUSPENDED) + goto err_out; + /* Prevent probing on this irq: */ + irq_settings_set_noprobe(desc); + irq_enable(desc); + check_irq_resend(desc, irq); + /* fall-through */ + } + default: + desc->depth--; + } +} + +/** + * enable_irq - enable handling of an irq + * @irq: Interrupt to enable + * + * Undoes the effect of one call to disable_irq(). If this + * matches the last disable, processing of interrupts on this + * IRQ line is re-enabled. + * + * This function may be called from IRQ context only when + * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL ! + */ +void enable_irq(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + + if (!desc) + return; + if (WARN(!desc->irq_data.chip, + KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq)) + goto out; + + __enable_irq(desc, irq, false); +out: + irq_put_desc_busunlock(desc, flags); +} +EXPORT_SYMBOL(enable_irq); + +static int set_irq_wake_real(unsigned int irq, unsigned int on) +{ + struct irq_desc *desc = irq_to_desc(irq); + int ret = -ENXIO; + + if (desc->irq_data.chip->irq_set_wake) + ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on); + + return ret; +} + +/** + * irq_set_irq_wake - control irq power management wakeup + * @irq: interrupt to control + * @on: enable/disable power management wakeup + * + * Enable/disable power management wakeup mode, which is + * disabled by default. Enables and disables must match, + * just as they match for non-wakeup mode support. + * + * Wakeup mode lets this IRQ wake the system from sleep + * states like "suspend to RAM". + */ +int irq_set_irq_wake(unsigned int irq, unsigned int on) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + int ret = 0; + + if (!desc) + return -EINVAL; + + /* wakeup-capable irqs can be shared between drivers that + * don't need to have the same sleep mode behaviors. + */ + if (on) { + if (desc->wake_depth++ == 0) { + ret = set_irq_wake_real(irq, on); + if (ret) + desc->wake_depth = 0; + else + irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE); + } + } else { + if (desc->wake_depth == 0) { + WARN(1, "Unbalanced IRQ %d wake disable\n", irq); + } else if (--desc->wake_depth == 0) { + ret = set_irq_wake_real(irq, on); + if (ret) + desc->wake_depth = 1; + else + irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE); + } + } + irq_put_desc_busunlock(desc, flags); + return ret; +} +EXPORT_SYMBOL(irq_set_irq_wake); + +/* + * Internal function that tells the architecture code whether a + * particular irq has been exclusively allocated or is available + * for driver use. + */ +int can_request_irq(unsigned int irq, unsigned long irqflags) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + int canrequest = 0; + + if (!desc) + return 0; + + if (irq_settings_can_request(desc)) { + if (desc->action) + if (irqflags & desc->action->flags & IRQF_SHARED) + canrequest =1; + } + irq_put_desc_unlock(desc, flags); + return canrequest; +} + +int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, + unsigned long flags) +{ + struct irq_chip *chip = desc->irq_data.chip; + int ret, unmask = 0; + + if (!chip || !chip->irq_set_type) { + /* + * IRQF_TRIGGER_* but the PIC does not support multiple + * flow-types? + */ + pr_debug("No set_type function for IRQ %d (%s)\n", irq, + chip ? (chip->name ? : "unknown") : "unknown"); + return 0; + } + + flags &= IRQ_TYPE_SENSE_MASK; + + if (chip->flags & IRQCHIP_SET_TYPE_MASKED) { + if (!irqd_irq_masked(&desc->irq_data)) + mask_irq(desc); + if (!irqd_irq_disabled(&desc->irq_data)) + unmask = 1; + } + + /* caller masked out all except trigger mode flags */ + ret = chip->irq_set_type(&desc->irq_data, flags); + + switch (ret) { + case IRQ_SET_MASK_OK: + irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK); + irqd_set(&desc->irq_data, flags); + + case IRQ_SET_MASK_OK_NOCOPY: + flags = irqd_get_trigger_type(&desc->irq_data); + irq_settings_set_trigger_mask(desc, flags); + irqd_clear(&desc->irq_data, IRQD_LEVEL); + irq_settings_clr_level(desc); + if (flags & IRQ_TYPE_LEVEL_MASK) { + irq_settings_set_level(desc); + irqd_set(&desc->irq_data, IRQD_LEVEL); + } + + ret = 0; + break; + default: + pr_err("setting trigger mode %lu for irq %u failed (%pF)\n", + flags, irq, chip->irq_set_type); + } + if (unmask) + unmask_irq(desc); + return ret; +} + +/* + * Default primary interrupt handler for threaded interrupts. Is + * assigned as primary handler when request_threaded_irq is called + * with handler == NULL. Useful for oneshot interrupts. + */ +static irqreturn_t irq_default_primary_handler(int irq, void *dev_id) +{ + return IRQ_WAKE_THREAD; +} + +/* + * Primary handler for nested threaded interrupts. Should never be + * called. + */ +static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) +{ + WARN(1, "Primary handler called for nested irq %d\n", irq); + return IRQ_NONE; +} + +static int irq_wait_for_interrupt(struct irqaction *action) +{ + set_current_state(TASK_INTERRUPTIBLE); + + while (!kthread_should_stop()) { + + if (test_and_clear_bit(IRQTF_RUNTHREAD, + &action->thread_flags)) { + __set_current_state(TASK_RUNNING); + return 0; + } + schedule(); + set_current_state(TASK_INTERRUPTIBLE); + } + __set_current_state(TASK_RUNNING); + return -1; +} + +/* + * Oneshot interrupts keep the irq line masked until the threaded + * handler finished. unmask if the interrupt has not been disabled and + * is marked MASKED. + */ +static void irq_finalize_oneshot(struct irq_desc *desc, + struct irqaction *action, bool force) +{ + if (!(desc->istate & IRQS_ONESHOT)) + return; +again: + chip_bus_lock(desc); + raw_spin_lock_irq(&desc->lock); + + /* + * Implausible though it may be we need to protect us against + * the following scenario: + * + * The thread is faster done than the hard interrupt handler + * on the other CPU. If we unmask the irq line then the + * interrupt can come in again and masks the line, leaves due + * to IRQS_INPROGRESS and the irq line is masked forever. + * + * This also serializes the state of shared oneshot handlers + * versus "desc->threads_onehsot |= action->thread_mask;" in + * irq_wake_thread(). See the comment there which explains the + * serialization. + */ + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { + raw_spin_unlock_irq(&desc->lock); + chip_bus_sync_unlock(desc); + cpu_relax(); + goto again; + } + + /* + * Now check again, whether the thread should run. Otherwise + * we would clear the threads_oneshot bit of this thread which + * was just set. + */ + if (!force && test_bit(IRQTF_RUNTHREAD, &action->thread_flags)) + goto out_unlock; + + desc->threads_oneshot &= ~action->thread_mask; + + if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data)) + unmask_irq(desc); + +out_unlock: + raw_spin_unlock_irq(&desc->lock); + chip_bus_sync_unlock(desc); +} + +#ifdef CONFIG_SMP +/* + * Check whether we need to chasnge the affinity of the interrupt thread. + */ +static void +irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) +{ + cpumask_var_t mask; + + if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags)) + return; + + /* + * In case we are out of memory we set IRQTF_AFFINITY again and + * try again next time + */ + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { + set_bit(IRQTF_AFFINITY, &action->thread_flags); + return; + } + + raw_spin_lock_irq(&desc->lock); + cpumask_copy(mask, desc->irq_data.affinity); + raw_spin_unlock_irq(&desc->lock); + + set_cpus_allowed_ptr(current, mask); + free_cpumask_var(mask); +} +#else +static inline void +irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { } +#endif + +/* + * Interrupts which are not explicitely requested as threaded + * interrupts rely on the implicit bh/preempt disable of the hard irq + * context. So we need to disable bh here to avoid deadlocks and other + * side effects. + */ +static irqreturn_t +irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action) +{ + irqreturn_t ret; + + local_bh_disable(); + ret = action->thread_fn(action->irq, action->dev_id); + irq_finalize_oneshot(desc, action, false); + local_bh_enable(); + return ret; +} + +/* + * Interrupts explicitely requested as threaded interupts want to be + * preemtible - many of them need to sleep and wait for slow busses to + * complete. + */ +static irqreturn_t irq_thread_fn(struct irq_desc *desc, + struct irqaction *action) +{ + irqreturn_t ret; + + ret = action->thread_fn(action->irq, action->dev_id); + irq_finalize_oneshot(desc, action, false); + return ret; +} + +/* + * Interrupt handler thread + */ +static int irq_thread(void *data) +{ + static const struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; + struct irqaction *action = data; + struct irq_desc *desc = irq_to_desc(action->irq); + irqreturn_t (*handler_fn)(struct irq_desc *desc, + struct irqaction *action); + int wake; + + if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD, + &action->thread_flags)) + handler_fn = irq_forced_thread_fn; + else + handler_fn = irq_thread_fn; + + sched_setscheduler(current, SCHED_FIFO, ¶m); + current->irqaction = action; + + while (!irq_wait_for_interrupt(action)) { + + irq_thread_check_affinity(desc, action); + + atomic_inc(&desc->threads_active); + + raw_spin_lock_irq(&desc->lock); + if (unlikely(irqd_irq_disabled(&desc->irq_data))) { + /* + * CHECKME: We might need a dedicated + * IRQ_THREAD_PENDING flag here, which + * retriggers the thread in check_irq_resend() + * but AFAICT IRQS_PENDING should be fine as it + * retriggers the interrupt itself --- tglx + */ + desc->istate |= IRQS_PENDING; + raw_spin_unlock_irq(&desc->lock); + } else { + irqreturn_t action_ret; + + raw_spin_unlock_irq(&desc->lock); + action_ret = handler_fn(desc, action); + if (!noirqdebug) + note_interrupt(action->irq, desc, action_ret); + } + + wake = atomic_dec_and_test(&desc->threads_active); + + if (wake && waitqueue_active(&desc->wait_for_threads)) + wake_up(&desc->wait_for_threads); + } + + /* Prevent a stale desc->threads_oneshot */ + irq_finalize_oneshot(desc, action, true); + + /* + * Clear irqaction. Otherwise exit_irq_thread() would make + * fuzz about an active irq thread going into nirvana. + */ + current->irqaction = NULL; + return 0; +} + +/* + * Called from do_exit() + */ +void exit_irq_thread(void) +{ + struct task_struct *tsk = current; + struct irq_desc *desc; + + if (!tsk->irqaction) + return; + + printk(KERN_ERR + "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n", + tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq); + + desc = irq_to_desc(tsk->irqaction->irq); + + /* + * Prevent a stale desc->threads_oneshot. Must be called + * before setting the IRQTF_DIED flag. + */ + irq_finalize_oneshot(desc, tsk->irqaction, true); + + /* + * Set the THREAD DIED flag to prevent further wakeups of the + * soon to be gone threaded handler. + */ + set_bit(IRQTF_DIED, &tsk->irqaction->flags); +} + +static void irq_setup_forced_threading(struct irqaction *new) +{ + if (!force_irqthreads) + return; + if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT)) + return; + + new->flags |= IRQF_ONESHOT; + + if (!new->thread_fn) { + set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); + new->thread_fn = new->handler; + new->handler = irq_default_primary_handler; + } +} + +/* + * Internal function to register an irqaction - typically used to + * allocate special interrupts that are part of the architecture. + */ +static int +__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) +{ + struct irqaction *old, **old_ptr; + const char *old_name = NULL; + unsigned long flags, thread_mask = 0; + int ret, nested, shared = 0; + cpumask_var_t mask; + + if (!desc) + return -EINVAL; + + if (desc->irq_data.chip == &no_irq_chip) + return -ENOSYS; + /* + * Some drivers like serial.c use request_irq() heavily, + * so we have to be careful not to interfere with a + * running system. + */ + if (new->flags & IRQF_SAMPLE_RANDOM) { + /* + * This function might sleep, we want to call it first, + * outside of the atomic block. + * Yes, this might clear the entropy pool if the wrong + * driver is attempted to be loaded, without actually + * installing a new handler, but is this really a problem, + * only the sysadmin is able to do this. + */ + rand_initialize_irq(irq); + } + + /* + * Check whether the interrupt nests into another interrupt + * thread. + */ + nested = irq_settings_is_nested_thread(desc); + if (nested) { + if (!new->thread_fn) + return -EINVAL; + /* + * Replace the primary handler which was provided from + * the driver for non nested interrupt handling by the + * dummy function which warns when called. + */ + new->handler = irq_nested_primary_handler; + } else { + if (irq_settings_can_thread(desc)) + irq_setup_forced_threading(new); + } + + /* + * Create a handler thread when a thread function is supplied + * and the interrupt does not nest into another interrupt + * thread. + */ + if (new->thread_fn && !nested) { + struct task_struct *t; + + t = kthread_create(irq_thread, new, "irq/%d-%s", irq, + new->name); + if (IS_ERR(t)) + return PTR_ERR(t); + /* + * We keep the reference to the task struct even if + * the thread dies to avoid that the interrupt code + * references an already freed task_struct. + */ + get_task_struct(t); + new->thread = t; + } + + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { + ret = -ENOMEM; + goto out_thread; + } + + /* + * The following block of code has to be executed atomically + */ + raw_spin_lock_irqsave(&desc->lock, flags); + old_ptr = &desc->action; + old = *old_ptr; + if (old) { + /* + * Can't share interrupts unless both agree to and are + * the same type (level, edge, polarity). So both flag + * fields must have IRQF_SHARED set and the bits which + * set the trigger type must match. Also all must + * agree on ONESHOT. + */ + if (!((old->flags & new->flags) & IRQF_SHARED) || + ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) || + ((old->flags ^ new->flags) & IRQF_ONESHOT)) { + old_name = old->name; + goto mismatch; + } + + /* All handlers must agree on per-cpuness */ + if ((old->flags & IRQF_PERCPU) != + (new->flags & IRQF_PERCPU)) + goto mismatch; + + /* add new interrupt at end of irq queue */ + do { + /* + * Or all existing action->thread_mask bits, + * so we can find the next zero bit for this + * new action. + */ + thread_mask |= old->thread_mask; + old_ptr = &old->next; + old = *old_ptr; + } while (old); + shared = 1; + } + + /* + * Setup the thread mask for this irqaction for ONESHOT. For + * !ONESHOT irqs the thread mask is 0 so we can avoid a + * conditional in irq_wake_thread(). + */ + if (new->flags & IRQF_ONESHOT) { + /* + * Unlikely to have 32 resp 64 irqs sharing one line, + * but who knows. + */ + if (thread_mask == ~0UL) { + ret = -EBUSY; + goto out_mask; + } + /* + * The thread_mask for the action is or'ed to + * desc->thread_active to indicate that the + * IRQF_ONESHOT thread handler has been woken, but not + * yet finished. The bit is cleared when a thread + * completes. When all threads of a shared interrupt + * line have completed desc->threads_active becomes + * zero and the interrupt line is unmasked. See + * handle.c:irq_wake_thread() for further information. + * + * If no thread is woken by primary (hard irq context) + * interrupt handlers, then desc->threads_active is + * also checked for zero to unmask the irq line in the + * affected hard irq flow handlers + * (handle_[fasteoi|level]_irq). + * + * The new action gets the first zero bit of + * thread_mask assigned. See the loop above which or's + * all existing action->thread_mask bits. + */ + new->thread_mask = 1 << ffz(thread_mask); + } + + if (!shared) { + init_waitqueue_head(&desc->wait_for_threads); + + /* Setup the type (level, edge polarity) if configured: */ + if (new->flags & IRQF_TRIGGER_MASK) { + ret = __irq_set_trigger(desc, irq, + new->flags & IRQF_TRIGGER_MASK); + + if (ret) + goto out_mask; + } + + desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \ + IRQS_ONESHOT | IRQS_WAITING); + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); + + if (new->flags & IRQF_PERCPU) { + irqd_set(&desc->irq_data, IRQD_PER_CPU); + irq_settings_set_per_cpu(desc); + } + + if (new->flags & IRQF_ONESHOT) + desc->istate |= IRQS_ONESHOT; + + if (irq_settings_can_autoenable(desc)) + irq_startup(desc, true); + else + /* Undo nested disables: */ + desc->depth = 1; + + /* Exclude IRQ from balancing if requested */ + if (new->flags & IRQF_NOBALANCING) { + irq_settings_set_no_balancing(desc); + irqd_set(&desc->irq_data, IRQD_NO_BALANCING); + } + + /* Set default affinity mask once everything is setup */ + setup_affinity(irq, desc, mask); + + } else if (new->flags & IRQF_TRIGGER_MASK) { + unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK; + unsigned int omsk = irq_settings_get_trigger_mask(desc); + + if (nmsk != omsk) + /* hope the handler works with current trigger mode */ + pr_warning("IRQ %d uses trigger mode %u; requested %u\n", + irq, nmsk, omsk); + } + + new->irq = irq; + *old_ptr = new; + + /* Reset broken irq detection when installing new handler */ + desc->irq_count = 0; + desc->irqs_unhandled = 0; + + /* + * Check whether we disabled the irq via the spurious handler + * before. Reenable it and give it another chance. + */ + if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) { + desc->istate &= ~IRQS_SPURIOUS_DISABLED; + __enable_irq(desc, irq, false); + } + + raw_spin_unlock_irqrestore(&desc->lock, flags); + + /* + * Strictly no need to wake it up, but hung_task complains + * when no hard interrupt wakes the thread up. + */ + if (new->thread) + wake_up_process(new->thread); + + register_irq_proc(irq, desc); + new->dir = NULL; + register_handler_proc(irq, new); + free_cpumask_var(mask); + + return 0; + +mismatch: +#ifdef CONFIG_DEBUG_SHIRQ + if (!(new->flags & IRQF_PROBE_SHARED)) { + printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq); + if (old_name) + printk(KERN_ERR "current handler: %s\n", old_name); + dump_stack(); + } +#endif + ret = -EBUSY; + +out_mask: + raw_spin_unlock_irqrestore(&desc->lock, flags); + free_cpumask_var(mask); + +out_thread: + if (new->thread) { + struct task_struct *t = new->thread; + + new->thread = NULL; + if (likely(!test_bit(IRQTF_DIED, &new->thread_flags))) + kthread_stop(t); + put_task_struct(t); + } + return ret; +} + +/** + * setup_irq - setup an interrupt + * @irq: Interrupt line to setup + * @act: irqaction for the interrupt + * + * Used to statically setup interrupts in the early boot process. + */ +int setup_irq(unsigned int irq, struct irqaction *act) +{ + int retval; + struct irq_desc *desc = irq_to_desc(irq); + + chip_bus_lock(desc); + retval = __setup_irq(irq, desc, act); + chip_bus_sync_unlock(desc); + + return retval; +} +EXPORT_SYMBOL_GPL(setup_irq); + + /* + * Internal function to unregister an irqaction - used to free + * regular and special interrupts that are part of the architecture. + */ +static struct irqaction *__free_irq(unsigned int irq, void *dev_id) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irqaction *action, **action_ptr; + unsigned long flags; + + WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq); + + if (!desc) + return NULL; + + raw_spin_lock_irqsave(&desc->lock, flags); + + /* + * There can be multiple actions per IRQ descriptor, find the right + * one based on the dev_id: + */ + action_ptr = &desc->action; + for (;;) { + action = *action_ptr; + + if (!action) { + WARN(1, "Trying to free already-free IRQ %d\n", irq); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + return NULL; + } + + if (action->dev_id == dev_id) + break; + action_ptr = &action->next; + } + + /* Found it - now remove it from the list of entries: */ + *action_ptr = action->next; + + /* Currently used only by UML, might disappear one day: */ +#ifdef CONFIG_IRQ_RELEASE_METHOD + if (desc->irq_data.chip->release) + desc->irq_data.chip->release(irq, dev_id); +#endif + + /* If this was the last handler, shut down the IRQ line: */ + if (!desc->action) + irq_shutdown(desc); + +#ifdef CONFIG_SMP + /* make sure affinity_hint is cleaned up */ + if (WARN_ON_ONCE(desc->affinity_hint)) + desc->affinity_hint = NULL; +#endif + + raw_spin_unlock_irqrestore(&desc->lock, flags); + + unregister_handler_proc(irq, action); + + /* Make sure it's not being used on another CPU: */ + synchronize_irq(irq); + +#ifdef CONFIG_DEBUG_SHIRQ + /* + * It's a shared IRQ -- the driver ought to be prepared for an IRQ + * event to happen even now it's being freed, so let's make sure that + * is so by doing an extra call to the handler .... + * + * ( We do this after actually deregistering it, to make sure that a + * 'real' IRQ doesn't run in * parallel with our fake. ) + */ + if (action->flags & IRQF_SHARED) { + local_irq_save(flags); + action->handler(irq, dev_id); + local_irq_restore(flags); + } +#endif + + if (action->thread) { + if (!test_bit(IRQTF_DIED, &action->thread_flags)) + kthread_stop(action->thread); + put_task_struct(action->thread); + } + + return action; +} + +/** + * remove_irq - free an interrupt + * @irq: Interrupt line to free + * @act: irqaction for the interrupt + * + * Used to remove interrupts statically setup by the early boot process. + */ +void remove_irq(unsigned int irq, struct irqaction *act) +{ + __free_irq(irq, act->dev_id); +} +EXPORT_SYMBOL_GPL(remove_irq); + +/** + * free_irq - free an interrupt allocated with request_irq + * @irq: Interrupt line to free + * @dev_id: Device identity to free + * + * Remove an interrupt handler. The handler is removed and if the + * interrupt line is no longer in use by any driver it is disabled. + * On a shared IRQ the caller must ensure the interrupt is disabled + * on the card it drives before calling this function. The function + * does not return until any executing interrupts for this IRQ + * have completed. + * + * This function must not be called from interrupt context. + */ +void free_irq(unsigned int irq, void *dev_id) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc) + return; + +#ifdef CONFIG_SMP + if (WARN_ON(desc->affinity_notify)) + desc->affinity_notify = NULL; +#endif + + chip_bus_lock(desc); + kfree(__free_irq(irq, dev_id)); + chip_bus_sync_unlock(desc); +} +EXPORT_SYMBOL(free_irq); + +/** + * request_threaded_irq - allocate an interrupt line + * @irq: Interrupt line to allocate + * @handler: Function to be called when the IRQ occurs. + * Primary handler for threaded interrupts + * If NULL and thread_fn != NULL the default + * primary handler is installed + * @thread_fn: Function called from the irq handler thread + * If NULL, no irq thread is created + * @irqflags: Interrupt type flags + * @devname: An ascii name for the claiming device + * @dev_id: A cookie passed back to the handler function + * + * This call allocates interrupt resources and enables the + * interrupt line and IRQ handling. From the point this + * call is made your handler function may be invoked. Since + * your handler function must clear any interrupt the board + * raises, you must take care both to initialise your hardware + * and to set up the interrupt handler in the right order. + * + * If you want to set up a threaded irq handler for your device + * then you need to supply @handler and @thread_fn. @handler ist + * still called in hard interrupt context and has to check + * whether the interrupt originates from the device. If yes it + * needs to disable the interrupt on the device and return + * IRQ_WAKE_THREAD which will wake up the handler thread and run + * @thread_fn. This split handler design is necessary to support + * shared interrupts. + * + * Dev_id must be globally unique. Normally the address of the + * device data structure is used as the cookie. Since the handler + * receives this value it makes sense to use it. + * + * If your interrupt is shared you must pass a non NULL dev_id + * as this is required when freeing the interrupt. + * + * Flags: + * + * IRQF_SHARED Interrupt is shared + * IRQF_SAMPLE_RANDOM The interrupt can be used for entropy + * IRQF_TRIGGER_* Specify active edge(s) or level + * + */ +int request_threaded_irq(unsigned int irq, irq_handler_t handler, + irq_handler_t thread_fn, unsigned long irqflags, + const char *devname, void *dev_id) +{ + struct irqaction *action; + struct irq_desc *desc; + int retval; + + /* + * Sanity-check: shared interrupts must pass in a real dev-ID, + * otherwise we'll have trouble later trying to figure out + * which interrupt is which (messes up the interrupt freeing + * logic etc). + */ + if ((irqflags & IRQF_SHARED) && !dev_id) + return -EINVAL; + + desc = irq_to_desc(irq); + if (!desc) + return -EINVAL; + + if (!irq_settings_can_request(desc)) + return -EINVAL; + + if (!handler) { + if (!thread_fn) + return -EINVAL; + handler = irq_default_primary_handler; + } + + action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); + if (!action) + return -ENOMEM; + + action->handler = handler; + action->thread_fn = thread_fn; + action->flags = irqflags; + action->name = devname; + action->dev_id = dev_id; + + chip_bus_lock(desc); + retval = __setup_irq(irq, desc, action); + chip_bus_sync_unlock(desc); + + if (retval) + kfree(action); + +#ifdef CONFIG_DEBUG_SHIRQ_FIXME + if (!retval && (irqflags & IRQF_SHARED)) { + /* + * It's a shared IRQ -- the driver ought to be prepared for it + * to happen immediately, so let's make sure.... + * We disable the irq to make sure that a 'real' IRQ doesn't + * run in parallel with our fake. + */ + unsigned long flags; + + disable_irq(irq); + local_irq_save(flags); + + handler(irq, dev_id); + + local_irq_restore(flags); + enable_irq(irq); + } +#endif + return retval; +} +EXPORT_SYMBOL(request_threaded_irq); + +/** + * request_any_context_irq - allocate an interrupt line + * @irq: Interrupt line to allocate + * @handler: Function to be called when the IRQ occurs. + * Threaded handler for threaded interrupts. + * @flags: Interrupt type flags + * @name: An ascii name for the claiming device + * @dev_id: A cookie passed back to the handler function + * + * This call allocates interrupt resources and enables the + * interrupt line and IRQ handling. It selects either a + * hardirq or threaded handling method depending on the + * context. + * + * On failure, it returns a negative value. On success, + * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED. + */ +int request_any_context_irq(unsigned int irq, irq_handler_t handler, + unsigned long flags, const char *name, void *dev_id) +{ + struct irq_desc *desc = irq_to_desc(irq); + int ret; + + if (!desc) + return -EINVAL; + + if (irq_settings_is_nested_thread(desc)) { + ret = request_threaded_irq(irq, NULL, handler, + flags, name, dev_id); + return !ret ? IRQC_IS_NESTED : ret; + } + + ret = request_irq(irq, handler, flags, name, dev_id); + return !ret ? IRQC_IS_HARDIRQ : ret; +} +EXPORT_SYMBOL_GPL(request_any_context_irq); diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c new file mode 100644 index 00000000..c3c89751 --- /dev/null +++ b/kernel/irq/migration.c @@ -0,0 +1,81 @@ + +#include <linux/irq.h> +#include <linux/interrupt.h> + +#include "internals.h" + +void irq_move_masked_irq(struct irq_data *idata) +{ + struct irq_desc *desc = irq_data_to_desc(idata); + struct irq_chip *chip = idata->chip; + + if (likely(!irqd_is_setaffinity_pending(&desc->irq_data))) + return; + + /* + * Paranoia: cpu-local interrupts shouldn't be calling in here anyway. + */ + if (!irqd_can_balance(&desc->irq_data)) { + WARN_ON(1); + return; + } + + irqd_clr_move_pending(&desc->irq_data); + + if (unlikely(cpumask_empty(desc->pending_mask))) + return; + + if (!chip->irq_set_affinity) + return; + + assert_raw_spin_locked(&desc->lock); + + /* + * If there was a valid mask to work with, please + * do the disable, re-program, enable sequence. + * This is *not* particularly important for level triggered + * but in a edge trigger case, we might be setting rte + * when an active trigger is coming in. This could + * cause some ioapics to mal-function. + * Being paranoid i guess! + * + * For correct operation this depends on the caller + * masking the irqs. + */ + if (likely(cpumask_any_and(desc->pending_mask, cpu_online_mask) + < nr_cpu_ids)) { + int ret = chip->irq_set_affinity(&desc->irq_data, + desc->pending_mask, false); + switch (ret) { + case IRQ_SET_MASK_OK: + cpumask_copy(desc->irq_data.affinity, desc->pending_mask); + case IRQ_SET_MASK_OK_NOCOPY: + irq_set_thread_affinity(desc); + } + } + + cpumask_clear(desc->pending_mask); +} + +void irq_move_irq(struct irq_data *idata) +{ + bool masked; + + if (likely(!irqd_is_setaffinity_pending(idata))) + return; + + if (unlikely(irqd_irq_disabled(idata))) + return; + + /* + * Be careful vs. already masked interrupts. If this is a + * threaded interrupt with ONESHOT set, we can end up with an + * interrupt storm. + */ + masked = irqd_irq_masked(idata); + if (!masked) + idata->chip->irq_mask(idata); + irq_move_masked_irq(idata); + if (!masked) + idata->chip->irq_unmask(idata); +} diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c new file mode 100644 index 00000000..bbf72985 --- /dev/null +++ b/kernel/irq/pm.c @@ -0,0 +1,131 @@ +/* + * linux/kernel/irq/pm.c + * + * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file contains power management functions related to interrupts. + */ + +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/syscore_ops.h> + +#include "internals.h" + +/** + * suspend_device_irqs - disable all currently enabled interrupt lines + * + * During system-wide suspend or hibernation device drivers need to be prevented + * from receiving interrupts and this function is provided for this purpose. + * It marks all interrupt lines in use, except for the timer ones, as disabled + * and sets the IRQS_SUSPENDED flag for each of them. + */ +void suspend_device_irqs(void) +{ + struct irq_desc *desc; + int irq; + + for_each_irq_desc(irq, desc) { + unsigned long flags; + + raw_spin_lock_irqsave(&desc->lock, flags); + __disable_irq(desc, irq, true); + raw_spin_unlock_irqrestore(&desc->lock, flags); + } + + for_each_irq_desc(irq, desc) + if (desc->istate & IRQS_SUSPENDED) + synchronize_irq(irq); +} +EXPORT_SYMBOL_GPL(suspend_device_irqs); + +void resume_irqs(bool want_early) +{ + struct irq_desc *desc; + int irq; + + for_each_irq_desc(irq, desc) { + unsigned long flags; + bool is_early = desc->action && + desc->action->flags & IRQF_EARLY_RESUME; + + if (is_early != want_early) + continue; + + raw_spin_lock_irqsave(&desc->lock, flags); + __enable_irq(desc, irq, true); + raw_spin_unlock_irqrestore(&desc->lock, flags); + } +} +EXPORT_SYMBOL_GPL(resume_irqs); + +/** + * irq_pm_syscore_ops - enable interrupt lines early + * + * Enable all interrupt lines with %IRQF_EARLY_RESUME set. + */ +static void irq_pm_syscore_resume(void) +{ + resume_irqs(true); +} + +static struct syscore_ops irq_pm_syscore_ops = { + .resume = irq_pm_syscore_resume, +}; + +static int __init irq_pm_init_ops(void) +{ + register_syscore_ops(&irq_pm_syscore_ops); + return 0; +} + +device_initcall(irq_pm_init_ops); + +/** + * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() + * + * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously + * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag + * set as well as those with %IRQF_FORCE_RESUME. + */ +void resume_device_irqs(void) +{ + resume_irqs(false); +} +EXPORT_SYMBOL_GPL(resume_device_irqs); + +/** + * check_wakeup_irqs - check if any wake-up interrupts are pending + */ +int check_wakeup_irqs(void) +{ + struct irq_desc *desc; + int irq; + + for_each_irq_desc(irq, desc) { + if (irqd_is_wakeup_set(&desc->irq_data)) { + if (desc->istate & IRQS_PENDING) { + pr_info("Wakeup IRQ %d %s pending, suspend aborted\n", + irq, + desc->action && desc->action->name ? + desc->action->name : ""); + return -EBUSY; + } + continue; + } + /* + * Check the non wakeup interrupts whether they need + * to be masked before finally going into suspend + * state. That's for hardware which has no wakeup + * source configuration facility. The chip + * implementation indicates that with + * IRQCHIP_MASK_ON_SUSPEND. + */ + if (desc->istate & IRQS_SUSPENDED && + irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND) + mask_irq(desc); + } + + return 0; +} diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c new file mode 100644 index 00000000..4bd4faa6 --- /dev/null +++ b/kernel/irq/proc.c @@ -0,0 +1,486 @@ +/* + * linux/kernel/irq/proc.c + * + * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar + * + * This file contains the /proc/irq/ handling code. + */ + +#include <linux/irq.h> +#include <linux/gfp.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> + +#include "internals.h" + +static struct proc_dir_entry *root_irq_dir; + +#ifdef CONFIG_SMP + +static int show_irq_affinity(int type, struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long)m->private); + const struct cpumask *mask = desc->irq_data.affinity; + +#ifdef CONFIG_GENERIC_PENDING_IRQ + if (irqd_is_setaffinity_pending(&desc->irq_data)) + mask = desc->pending_mask; +#endif + if (type) + seq_cpumask_list(m, mask); + else + seq_cpumask(m, mask); + seq_putc(m, '\n'); + return 0; +} + +static int irq_affinity_hint_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long)m->private); + unsigned long flags; + cpumask_var_t mask; + + if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) + return -ENOMEM; + + raw_spin_lock_irqsave(&desc->lock, flags); + if (desc->affinity_hint) + cpumask_copy(mask, desc->affinity_hint); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + seq_cpumask(m, mask); + seq_putc(m, '\n'); + free_cpumask_var(mask); + + return 0; +} + +#ifndef is_affinity_mask_valid +#define is_affinity_mask_valid(val) 1 +#endif + +int no_irq_affinity; +static int irq_affinity_proc_show(struct seq_file *m, void *v) +{ + return show_irq_affinity(0, m, v); +} + +static int irq_affinity_list_proc_show(struct seq_file *m, void *v) +{ + return show_irq_affinity(1, m, v); +} + + +static ssize_t write_irq_affinity(int type, struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + unsigned int irq = (int)(long)PDE(file->f_path.dentry->d_inode)->data; + cpumask_var_t new_value; + int err; + + if (!irq_can_set_affinity(irq) || no_irq_affinity) + return -EIO; + + if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) + return -ENOMEM; + + if (type) + err = cpumask_parselist_user(buffer, count, new_value); + else + err = cpumask_parse_user(buffer, count, new_value); + if (err) + goto free_cpumask; + + if (!is_affinity_mask_valid(new_value)) { + err = -EINVAL; + goto free_cpumask; + } + + /* + * Do not allow disabling IRQs completely - it's a too easy + * way to make the system unusable accidentally :-) At least + * one online CPU still has to be targeted. + */ + if (!cpumask_intersects(new_value, cpu_online_mask)) { + /* Special case for empty set - allow the architecture + code to set default SMP affinity. */ + err = irq_select_affinity_usr(irq, new_value) ? -EINVAL : count; + } else { + irq_set_affinity(irq, new_value); + err = count; + } + +free_cpumask: + free_cpumask_var(new_value); + return err; +} + +static ssize_t irq_affinity_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + return write_irq_affinity(0, file, buffer, count, pos); +} + +static ssize_t irq_affinity_list_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + return write_irq_affinity(1, file, buffer, count, pos); +} + +static int irq_affinity_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_proc_show, PDE(inode)->data); +} + +static int irq_affinity_list_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_list_proc_show, PDE(inode)->data); +} + +static int irq_affinity_hint_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_hint_proc_show, PDE(inode)->data); +} + +static const struct file_operations irq_affinity_proc_fops = { + .open = irq_affinity_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = irq_affinity_proc_write, +}; + +static const struct file_operations irq_affinity_hint_proc_fops = { + .open = irq_affinity_hint_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations irq_affinity_list_proc_fops = { + .open = irq_affinity_list_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = irq_affinity_list_proc_write, +}; + +static int default_affinity_show(struct seq_file *m, void *v) +{ + seq_cpumask(m, irq_default_affinity); + seq_putc(m, '\n'); + return 0; +} + +static ssize_t default_affinity_write(struct file *file, + const char __user *buffer, size_t count, loff_t *ppos) +{ + cpumask_var_t new_value; + int err; + + if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) + return -ENOMEM; + + err = cpumask_parse_user(buffer, count, new_value); + if (err) + goto out; + + if (!is_affinity_mask_valid(new_value)) { + err = -EINVAL; + goto out; + } + + /* + * Do not allow disabling IRQs completely - it's a too easy + * way to make the system unusable accidentally :-) At least + * one online CPU still has to be targeted. + */ + if (!cpumask_intersects(new_value, cpu_online_mask)) { + err = -EINVAL; + goto out; + } + + cpumask_copy(irq_default_affinity, new_value); + err = count; + +out: + free_cpumask_var(new_value); + return err; +} + +static int default_affinity_open(struct inode *inode, struct file *file) +{ + return single_open(file, default_affinity_show, PDE(inode)->data); +} + +static const struct file_operations default_affinity_proc_fops = { + .open = default_affinity_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = default_affinity_write, +}; + +static int irq_node_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long) m->private); + + seq_printf(m, "%d\n", desc->irq_data.node); + return 0; +} + +static int irq_node_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_node_proc_show, PDE(inode)->data); +} + +static const struct file_operations irq_node_proc_fops = { + .open = irq_node_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; +#endif + +static int irq_spurious_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long) m->private); + + seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n", + desc->irq_count, desc->irqs_unhandled, + jiffies_to_msecs(desc->last_unhandled)); + return 0; +} + +static int irq_spurious_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_spurious_proc_show, PDE(inode)->data); +} + +static const struct file_operations irq_spurious_proc_fops = { + .open = irq_spurious_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +#define MAX_NAMELEN 128 + +static int name_unique(unsigned int irq, struct irqaction *new_action) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irqaction *action; + unsigned long flags; + int ret = 1; + + raw_spin_lock_irqsave(&desc->lock, flags); + for (action = desc->action ; action; action = action->next) { + if ((action != new_action) && action->name && + !strcmp(new_action->name, action->name)) { + ret = 0; + break; + } + } + raw_spin_unlock_irqrestore(&desc->lock, flags); + return ret; +} + +void register_handler_proc(unsigned int irq, struct irqaction *action) +{ + char name [MAX_NAMELEN]; + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc->dir || action->dir || !action->name || + !name_unique(irq, action)) + return; + + memset(name, 0, MAX_NAMELEN); + snprintf(name, MAX_NAMELEN, "%s", action->name); + + /* create /proc/irq/1234/handler/ */ + action->dir = proc_mkdir(name, desc->dir); +} + +#undef MAX_NAMELEN + +#define MAX_NAMELEN 10 + +void register_irq_proc(unsigned int irq, struct irq_desc *desc) +{ + char name [MAX_NAMELEN]; + + if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip) || desc->dir) + return; + + memset(name, 0, MAX_NAMELEN); + sprintf(name, "%d", irq); + + /* create /proc/irq/1234 */ + desc->dir = proc_mkdir(name, root_irq_dir); + if (!desc->dir) + return; + +#ifdef CONFIG_SMP + /* create /proc/irq/<irq>/smp_affinity */ + proc_create_data("smp_affinity", 0600, desc->dir, + &irq_affinity_proc_fops, (void *)(long)irq); + + /* create /proc/irq/<irq>/affinity_hint */ + proc_create_data("affinity_hint", 0400, desc->dir, + &irq_affinity_hint_proc_fops, (void *)(long)irq); + + /* create /proc/irq/<irq>/smp_affinity_list */ + proc_create_data("smp_affinity_list", 0600, desc->dir, + &irq_affinity_list_proc_fops, (void *)(long)irq); + + proc_create_data("node", 0444, desc->dir, + &irq_node_proc_fops, (void *)(long)irq); +#endif + + proc_create_data("spurious", 0444, desc->dir, + &irq_spurious_proc_fops, (void *)(long)irq); +} + +void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) +{ + char name [MAX_NAMELEN]; + + if (!root_irq_dir || !desc->dir) + return; +#ifdef CONFIG_SMP + remove_proc_entry("smp_affinity", desc->dir); + remove_proc_entry("affinity_hint", desc->dir); + remove_proc_entry("smp_affinity_list", desc->dir); + remove_proc_entry("node", desc->dir); +#endif + remove_proc_entry("spurious", desc->dir); + + memset(name, 0, MAX_NAMELEN); + sprintf(name, "%u", irq); + remove_proc_entry(name, root_irq_dir); +} + +#undef MAX_NAMELEN + +void unregister_handler_proc(unsigned int irq, struct irqaction *action) +{ + if (action->dir) { + struct irq_desc *desc = irq_to_desc(irq); + + remove_proc_entry(action->dir->name, desc->dir); + } +} + +static void register_default_affinity_proc(void) +{ +#ifdef CONFIG_SMP + proc_create("irq/default_smp_affinity", 0600, NULL, + &default_affinity_proc_fops); +#endif +} + +void init_irq_proc(void) +{ + unsigned int irq; + struct irq_desc *desc; + + /* create /proc/irq */ + root_irq_dir = proc_mkdir("irq", NULL); + if (!root_irq_dir) + return; + + register_default_affinity_proc(); + + /* + * Create entries for all existing IRQs. + */ + for_each_irq_desc(irq, desc) { + if (!desc) + continue; + + register_irq_proc(irq, desc); + } +} + +#ifdef CONFIG_GENERIC_IRQ_SHOW + +int __weak arch_show_interrupts(struct seq_file *p, int prec) +{ + return 0; +} + +#ifndef ACTUAL_NR_IRQS +# define ACTUAL_NR_IRQS nr_irqs +#endif + +int show_interrupts(struct seq_file *p, void *v) +{ + static int prec; + + unsigned long flags, any_count = 0; + int i = *(loff_t *) v, j; + struct irqaction *action; + struct irq_desc *desc; + + if (i > ACTUAL_NR_IRQS) + return 0; + + if (i == ACTUAL_NR_IRQS) + return arch_show_interrupts(p, prec); + + /* print header and calculate the width of the first column */ + if (i == 0) { + for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec) + j *= 10; + + seq_printf(p, "%*s", prec + 8, ""); + for_each_online_cpu(j) + seq_printf(p, "CPU%-8d", j); + seq_putc(p, '\n'); + } + + desc = irq_to_desc(i); + if (!desc) + return 0; + + raw_spin_lock_irqsave(&desc->lock, flags); + for_each_online_cpu(j) + any_count |= kstat_irqs_cpu(i, j); + action = desc->action; + if (!action && !any_count) + goto out; + + seq_printf(p, "%*d: ", prec, i); + for_each_online_cpu(j) + seq_printf(p, "%10u ", kstat_irqs_cpu(i, j)); + + if (desc->irq_data.chip) { + if (desc->irq_data.chip->irq_print_chip) + desc->irq_data.chip->irq_print_chip(&desc->irq_data, p); + else if (desc->irq_data.chip->name) + seq_printf(p, " %8s", desc->irq_data.chip->name); + else + seq_printf(p, " %8s", "-"); + } else { + seq_printf(p, " %8s", "None"); + } +#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL + seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge"); +#endif + if (desc->name) + seq_printf(p, "-%-8s", desc->name); + + if (action) { + seq_printf(p, " %s", action->name); + while ((action = action->next) != NULL) + seq_printf(p, ", %s", action->name); + } + + seq_putc(p, '\n'); +out: + raw_spin_unlock_irqrestore(&desc->lock, flags); + return 0; +} +#endif diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c new file mode 100644 index 00000000..14dd5761 --- /dev/null +++ b/kernel/irq/resend.c @@ -0,0 +1,80 @@ +/* + * linux/kernel/irq/resend.c + * + * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar + * Copyright (C) 2005-2006, Thomas Gleixner + * + * This file contains the IRQ-resend code + * + * If the interrupt is waiting to be processed, we try to re-run it. + * We can't directly run it from here since the caller might be in an + * interrupt-protected region. Not all irq controller chips can + * retrigger interrupts at the hardware level, so in those cases + * we allow the resending of IRQs via a tasklet. + */ + +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/interrupt.h> + +#include "internals.h" + +#ifdef CONFIG_HARDIRQS_SW_RESEND + +/* Bitmap to handle software resend of interrupts: */ +static DECLARE_BITMAP(irqs_resend, IRQ_BITMAP_BITS); + +/* + * Run software resends of IRQ's + */ +static void resend_irqs(unsigned long arg) +{ + struct irq_desc *desc; + int irq; + + while (!bitmap_empty(irqs_resend, nr_irqs)) { + irq = find_first_bit(irqs_resend, nr_irqs); + clear_bit(irq, irqs_resend); + desc = irq_to_desc(irq); + local_irq_disable(); + desc->handle_irq(irq, desc); + local_irq_enable(); + } +} + +/* Tasklet to handle resend: */ +static DECLARE_TASKLET(resend_tasklet, resend_irqs, 0); + +#endif + +/* + * IRQ resend + * + * Is called with interrupts disabled and desc->lock held. + */ +void check_irq_resend(struct irq_desc *desc, unsigned int irq) +{ + /* + * We do not resend level type interrupts. Level type + * interrupts are resent by hardware when they are still + * active. + */ + if (irq_settings_is_level(desc)) + return; + if (desc->istate & IRQS_REPLAY) + return; + if (desc->istate & IRQS_PENDING) { + desc->istate &= ~IRQS_PENDING; + desc->istate |= IRQS_REPLAY; + + if (!desc->irq_data.chip->irq_retrigger || + !desc->irq_data.chip->irq_retrigger(&desc->irq_data)) { +#ifdef CONFIG_HARDIRQS_SW_RESEND + /* Set it pending and activate the softirq: */ + set_bit(irq, irqs_resend); + tasklet_schedule(&resend_tasklet); +#endif + } + } +} diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h new file mode 100644 index 00000000..f1667833 --- /dev/null +++ b/kernel/irq/settings.h @@ -0,0 +1,142 @@ +/* + * Internal header to deal with irq_desc->status which will be renamed + * to irq_desc->settings. + */ +enum { + _IRQ_DEFAULT_INIT_FLAGS = IRQ_DEFAULT_INIT_FLAGS, + _IRQ_PER_CPU = IRQ_PER_CPU, + _IRQ_LEVEL = IRQ_LEVEL, + _IRQ_NOPROBE = IRQ_NOPROBE, + _IRQ_NOREQUEST = IRQ_NOREQUEST, + _IRQ_NOTHREAD = IRQ_NOTHREAD, + _IRQ_NOAUTOEN = IRQ_NOAUTOEN, + _IRQ_MOVE_PCNTXT = IRQ_MOVE_PCNTXT, + _IRQ_NO_BALANCING = IRQ_NO_BALANCING, + _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, + _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, +}; + +#define IRQ_PER_CPU GOT_YOU_MORON +#define IRQ_NO_BALANCING GOT_YOU_MORON +#define IRQ_LEVEL GOT_YOU_MORON +#define IRQ_NOPROBE GOT_YOU_MORON +#define IRQ_NOREQUEST GOT_YOU_MORON +#define IRQ_NOTHREAD GOT_YOU_MORON +#define IRQ_NOAUTOEN GOT_YOU_MORON +#define IRQ_NESTED_THREAD GOT_YOU_MORON +#undef IRQF_MODIFY_MASK +#define IRQF_MODIFY_MASK GOT_YOU_MORON + +static inline void +irq_settings_clr_and_set(struct irq_desc *desc, u32 clr, u32 set) +{ + desc->status_use_accessors &= ~(clr & _IRQF_MODIFY_MASK); + desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK); +} + +static inline bool irq_settings_is_per_cpu(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_PER_CPU; +} + +static inline void irq_settings_set_per_cpu(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_PER_CPU; +} + +static inline void irq_settings_set_no_balancing(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NO_BALANCING; +} + +static inline bool irq_settings_has_no_balance_set(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NO_BALANCING; +} + +static inline u32 irq_settings_get_trigger_mask(struct irq_desc *desc) +{ + return desc->status_use_accessors & IRQ_TYPE_SENSE_MASK; +} + +static inline void +irq_settings_set_trigger_mask(struct irq_desc *desc, u32 mask) +{ + desc->status_use_accessors &= ~IRQ_TYPE_SENSE_MASK; + desc->status_use_accessors |= mask & IRQ_TYPE_SENSE_MASK; +} + +static inline bool irq_settings_is_level(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_LEVEL; +} + +static inline void irq_settings_clr_level(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_LEVEL; +} + +static inline void irq_settings_set_level(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_LEVEL; +} + +static inline bool irq_settings_can_request(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOREQUEST); +} + +static inline void irq_settings_clr_norequest(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOREQUEST; +} + +static inline void irq_settings_set_norequest(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOREQUEST; +} + +static inline bool irq_settings_can_thread(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOTHREAD); +} + +static inline void irq_settings_clr_nothread(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOTHREAD; +} + +static inline void irq_settings_set_nothread(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOTHREAD; +} + +static inline bool irq_settings_can_probe(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOPROBE); +} + +static inline void irq_settings_clr_noprobe(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOPROBE; +} + +static inline void irq_settings_set_noprobe(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOPROBE; +} + +static inline bool irq_settings_can_move_pcntxt(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_MOVE_PCNTXT; +} + +static inline bool irq_settings_can_autoenable(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOAUTOEN); +} + +static inline bool irq_settings_is_nested_thread(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NESTED_THREAD; +} diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c new file mode 100644 index 00000000..dc813a94 --- /dev/null +++ b/kernel/irq/spurious.c @@ -0,0 +1,364 @@ +/* + * linux/kernel/irq/spurious.c + * + * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar + * + * This file contains spurious interrupt handling. + */ + +#include <linux/jiffies.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/kallsyms.h> +#include <linux/interrupt.h> +#include <linux/moduleparam.h> +#include <linux/timer.h> + +#include "internals.h" + +static int irqfixup __read_mostly; + +#define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10) +static void poll_spurious_irqs(unsigned long dummy); +static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0); +static int irq_poll_cpu; +static atomic_t irq_poll_active; + +/* + * We wait here for a poller to finish. + * + * If the poll runs on this CPU, then we yell loudly and return + * false. That will leave the interrupt line disabled in the worst + * case, but it should never happen. + * + * We wait until the poller is done and then recheck disabled and + * action (about to be disabled). Only if it's still active, we return + * true and let the handler run. + */ +bool irq_wait_for_poll(struct irq_desc *desc) +{ + if (WARN_ONCE(irq_poll_cpu == smp_processor_id(), + "irq poll in progress on cpu %d for irq %d\n", + smp_processor_id(), desc->irq_data.irq)) + return false; + +#ifdef CONFIG_SMP + do { + raw_spin_unlock(&desc->lock); + while (irqd_irq_inprogress(&desc->irq_data)) + cpu_relax(); + raw_spin_lock(&desc->lock); + } while (irqd_irq_inprogress(&desc->irq_data)); + /* Might have been disabled in meantime */ + return !irqd_irq_disabled(&desc->irq_data) && desc->action; +#else + return false; +#endif +} + + +/* + * Recovery handler for misrouted interrupts. + */ +static int try_one_irq(int irq, struct irq_desc *desc, bool force) +{ + irqreturn_t ret = IRQ_NONE; + struct irqaction *action; + + raw_spin_lock(&desc->lock); + + /* PER_CPU and nested thread interrupts are never polled */ + if (irq_settings_is_per_cpu(desc) || irq_settings_is_nested_thread(desc)) + goto out; + + /* + * Do not poll disabled interrupts unless the spurious + * disabled poller asks explicitely. + */ + if (irqd_irq_disabled(&desc->irq_data) && !force) + goto out; + + /* + * All handlers must agree on IRQF_SHARED, so we test just the + * first. Check for action->next as well. + */ + action = desc->action; + if (!action || !(action->flags & IRQF_SHARED) || + (action->flags & __IRQF_TIMER) || + (action->handler(irq, action->dev_id) == IRQ_HANDLED) || + !action->next) + goto out; + + /* Already running on another processor */ + if (irqd_irq_inprogress(&desc->irq_data)) { + /* + * Already running: If it is shared get the other + * CPU to go looking for our mystery interrupt too + */ + desc->istate |= IRQS_PENDING; + goto out; + } + + /* Mark it poll in progress */ + desc->istate |= IRQS_POLL_INPROGRESS; + do { + if (handle_irq_event(desc) == IRQ_HANDLED) + ret = IRQ_HANDLED; + action = desc->action; + } while ((desc->istate & IRQS_PENDING) && action); + desc->istate &= ~IRQS_POLL_INPROGRESS; +out: + raw_spin_unlock(&desc->lock); + return ret == IRQ_HANDLED; +} + +static int misrouted_irq(int irq) +{ + struct irq_desc *desc; + int i, ok = 0; + + if (atomic_inc_return(&irq_poll_active) != 1) + goto out; + + irq_poll_cpu = smp_processor_id(); + + for_each_irq_desc(i, desc) { + if (!i) + continue; + + if (i == irq) /* Already tried */ + continue; + + if (try_one_irq(i, desc, false)) + ok = 1; + } +out: + atomic_dec(&irq_poll_active); + /* So the caller can adjust the irq error counts */ + return ok; +} + +static void poll_spurious_irqs(unsigned long dummy) +{ + struct irq_desc *desc; + int i; + + if (atomic_inc_return(&irq_poll_active) != 1) + goto out; + irq_poll_cpu = smp_processor_id(); + + for_each_irq_desc(i, desc) { + unsigned int state; + + if (!i) + continue; + + /* Racy but it doesn't matter */ + state = desc->istate; + barrier(); + if (!(state & IRQS_SPURIOUS_DISABLED)) + continue; + + local_irq_disable(); + try_one_irq(i, desc, true); + local_irq_enable(); + } +out: + atomic_dec(&irq_poll_active); + mod_timer(&poll_spurious_irq_timer, + jiffies + POLL_SPURIOUS_IRQ_INTERVAL); +} + +static inline int bad_action_ret(irqreturn_t action_ret) +{ + if (likely(action_ret <= (IRQ_HANDLED | IRQ_WAKE_THREAD))) + return 0; + return 1; +} + +/* + * If 99,900 of the previous 100,000 interrupts have not been handled + * then assume that the IRQ is stuck in some manner. Drop a diagnostic + * and try to turn the IRQ off. + * + * (The other 100-of-100,000 interrupts may have been a correctly + * functioning device sharing an IRQ with the failing one) + */ +static void +__report_bad_irq(unsigned int irq, struct irq_desc *desc, + irqreturn_t action_ret) +{ + struct irqaction *action; + unsigned long flags; + + if (bad_action_ret(action_ret)) { + printk(KERN_ERR "irq event %d: bogus return value %x\n", + irq, action_ret); + } else { + printk(KERN_ERR "irq %d: nobody cared (try booting with " + "the \"irqpoll\" option)\n", irq); + } + dump_stack(); + printk(KERN_ERR "handlers:\n"); + + /* + * We need to take desc->lock here. note_interrupt() is called + * w/o desc->lock held, but IRQ_PROGRESS set. We might race + * with something else removing an action. It's ok to take + * desc->lock here. See synchronize_irq(). + */ + raw_spin_lock_irqsave(&desc->lock, flags); + action = desc->action; + while (action) { + printk(KERN_ERR "[<%p>] %pf", action->handler, action->handler); + if (action->thread_fn) + printk(KERN_CONT " threaded [<%p>] %pf", + action->thread_fn, action->thread_fn); + printk(KERN_CONT "\n"); + action = action->next; + } + raw_spin_unlock_irqrestore(&desc->lock, flags); +} + +static void +report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) +{ + static int count = 100; + + if (count > 0) { + count--; + __report_bad_irq(irq, desc, action_ret); + } +} + +static inline int +try_misrouted_irq(unsigned int irq, struct irq_desc *desc, + irqreturn_t action_ret) +{ + struct irqaction *action; + + if (!irqfixup) + return 0; + + /* We didn't actually handle the IRQ - see if it was misrouted? */ + if (action_ret == IRQ_NONE) + return 1; + + /* + * But for 'irqfixup == 2' we also do it for handled interrupts if + * they are marked as IRQF_IRQPOLL (or for irq zero, which is the + * traditional PC timer interrupt.. Legacy) + */ + if (irqfixup < 2) + return 0; + + if (!irq) + return 1; + + /* + * Since we don't get the descriptor lock, "action" can + * change under us. We don't really care, but we don't + * want to follow a NULL pointer. So tell the compiler to + * just load it once by using a barrier. + */ + action = desc->action; + barrier(); + return action && (action->flags & IRQF_IRQPOLL); +} + +void note_interrupt(unsigned int irq, struct irq_desc *desc, + irqreturn_t action_ret) +{ + if (desc->istate & IRQS_POLL_INPROGRESS) + return; + + /* we get here again via the threaded handler */ + if (action_ret == IRQ_WAKE_THREAD) + return; + + if (bad_action_ret(action_ret)) { + report_bad_irq(irq, desc, action_ret); + return; + } + + if (unlikely(action_ret == IRQ_NONE)) { + /* + * If we are seeing only the odd spurious IRQ caused by + * bus asynchronicity then don't eventually trigger an error, + * otherwise the counter becomes a doomsday timer for otherwise + * working systems + */ + if (time_after(jiffies, desc->last_unhandled + HZ/10)) + desc->irqs_unhandled = 1; + else + desc->irqs_unhandled++; + desc->last_unhandled = jiffies; + } + + if (unlikely(try_misrouted_irq(irq, desc, action_ret))) { + int ok = misrouted_irq(irq); + if (action_ret == IRQ_NONE) + desc->irqs_unhandled -= ok; + } + + desc->irq_count++; + if (likely(desc->irq_count < 100000)) + return; + + desc->irq_count = 0; + if (unlikely(desc->irqs_unhandled > 99900)) { + /* + * The interrupt is stuck + */ + __report_bad_irq(irq, desc, action_ret); + /* + * Now kill the IRQ + */ + printk(KERN_EMERG "Disabling IRQ #%d\n", irq); + desc->istate |= IRQS_SPURIOUS_DISABLED; + desc->depth++; + irq_disable(desc); + + mod_timer(&poll_spurious_irq_timer, + jiffies + POLL_SPURIOUS_IRQ_INTERVAL); + } + desc->irqs_unhandled = 0; +} + +int noirqdebug __read_mostly; + +int noirqdebug_setup(char *str) +{ + noirqdebug = 1; + printk(KERN_INFO "IRQ lockup detection disabled\n"); + + return 1; +} + +__setup("noirqdebug", noirqdebug_setup); +module_param(noirqdebug, bool, 0644); +MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true"); + +static int __init irqfixup_setup(char *str) +{ + irqfixup = 1; + printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); + printk(KERN_WARNING "This may impact system performance.\n"); + + return 1; +} + +__setup("irqfixup", irqfixup_setup); +module_param(irqfixup, int, 0644); + +static int __init irqpoll_setup(char *str) +{ + irqfixup = 2; + printk(KERN_WARNING "Misrouted IRQ fixup and polling support " + "enabled\n"); + printk(KERN_WARNING "This may significantly impact system " + "performance\n"); + return 1; +} + +__setup("irqpoll", irqpoll_setup); |