diff options
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/autoprobe.c | 4 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 42 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 2 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 46 |
4 files changed, 75 insertions, 19 deletions
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c index 342d8f4..0119b9d 100644 --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -53,7 +53,7 @@ unsigned long probe_irq_on(void) if (desc->irq_data.chip->irq_set_type) desc->irq_data.chip->irq_set_type(&desc->irq_data, IRQ_TYPE_PROBE); - irq_startup(desc); + irq_startup(desc, false); } raw_spin_unlock_irq(&desc->lock); } @@ -70,7 +70,7 @@ unsigned long probe_irq_on(void) raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; - if (irq_startup(desc)) + if (irq_startup(desc, false)) desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index f7c543a..fb7db75 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -157,19 +157,22 @@ 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) +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) { - int ret = desc->irq_data.chip->irq_startup(&desc->irq_data); + ret = desc->irq_data.chip->irq_startup(&desc->irq_data); irq_state_clr_masked(desc); - return ret; + } else { + irq_enable(desc); } - - irq_enable(desc); - return 0; + if (resend) + check_irq_resend(desc, desc->irq_data.irq); + return ret; } void irq_shutdown(struct irq_desc *desc) @@ -330,6 +333,24 @@ out_unlock: } 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 @@ -362,8 +383,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) handle_irq_event(desc); - if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT)) - unmask_irq(desc); + cond_unmask_irq(desc); + out_unlock: raw_spin_unlock(&desc->lock); } @@ -417,6 +438,9 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *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: @@ -625,7 +649,7 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, irq_settings_set_noprobe(desc); irq_settings_set_norequest(desc); irq_settings_set_nothread(desc); - irq_startup(desc); + irq_startup(desc, true); } out: irq_put_desc_busunlock(desc, flags); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index b795231..40378ff 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -67,7 +67,7 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, 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); +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); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index a9a9dbe..0f0d470 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -985,6 +985,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) /* 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; @@ -993,14 +998,41 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) } /* - * Setup the thread mask for this irqaction. Unlikely to have - * 32 resp 64 irqs sharing one line, but who knows. + * 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 && thread_mask == ~0UL) { - ret = -EBUSY; - goto out_mask; + 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); } - new->thread_mask = 1 << ffz(thread_mask); if (!shared) { init_waitqueue_head(&desc->wait_for_threads); @@ -1027,7 +1059,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) desc->istate |= IRQS_ONESHOT; if (irq_settings_can_autoenable(desc)) - irq_startup(desc); + irq_startup(desc, true); else /* Undo nested disables: */ desc->depth = 1; |