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Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/autoprobe.c4
-rw-r--r--kernel/irq/chip.c42
-rw-r--r--kernel/irq/handle.c3
-rw-r--r--kernel/irq/internals.h2
-rw-r--r--kernel/irq/manage.c17
-rw-r--r--kernel/irq/settings.h12
-rw-r--r--kernel/irq/spurious.c10
7 files changed, 76 insertions, 14 deletions
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
index 342d8f44e401..0119b9d467ae 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 f7c543a801d9..fb7db75ee0c8 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/handle.c b/kernel/irq/handle.c
index 470d08c82bbe..634620c1b291 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -156,8 +156,11 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
action = action->next;
} while (action);
+#ifndef CONFIG_PREEMPT_RT_FULL
+ /* FIXME: Can we unbreak that ? */
if (random & IRQF_SAMPLE_RANDOM)
add_interrupt_randomness(irq);
+#endif
if (!noirqdebug)
note_interrupt(irq, desc, retval);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index a73dd6c7372d..e1a8b646c9fe 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 1da999f5e746..fd301aa5665d 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -18,6 +18,7 @@
#include "internals.h"
#ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
__read_mostly bool force_irqthreads;
static int __init setup_forced_irqthreads(char *arg)
@@ -26,6 +27,7 @@ static int __init setup_forced_irqthreads(char *arg)
return 0;
}
early_param("threadirqs", setup_forced_irqthreads);
+# endif
#endif
/**
@@ -740,7 +742,15 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
local_bh_disable();
ret = action->thread_fn(action->irq, action->dev_id);
irq_finalize_oneshot(desc, action, false);
- local_bh_enable();
+ /*
+ * Interrupts which have real time requirements can be set up
+ * to avoid softirq processing in the thread handler. This is
+ * safe as these interrupts do not raise soft interrupts.
+ */
+ if (irq_settings_no_softirq_call(desc))
+ _local_bh_enable();
+ else
+ local_bh_enable();
return ret;
}
@@ -1027,7 +1037,7 @@ __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;
@@ -1038,6 +1048,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
}
+ if (new->flags & IRQF_NO_SOFTIRQ_CALL)
+ irq_settings_set_no_softirq_call(desc);
+
/* Set default affinity mask once everything is setup */
setup_affinity(irq, desc, mask);
diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h
index 1162f1030f18..0d2c381c2bdb 100644
--- a/kernel/irq/settings.h
+++ b/kernel/irq/settings.h
@@ -14,6 +14,7 @@ enum {
_IRQ_NO_BALANCING = IRQ_NO_BALANCING,
_IRQ_NESTED_THREAD = IRQ_NESTED_THREAD,
_IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID,
+ _IRQ_NO_SOFTIRQ_CALL = IRQ_NO_SOFTIRQ_CALL,
_IRQF_MODIFY_MASK = IRQF_MODIFY_MASK,
};
@@ -26,6 +27,7 @@ enum {
#define IRQ_NOAUTOEN GOT_YOU_MORON
#define IRQ_NESTED_THREAD GOT_YOU_MORON
#define IRQ_PER_CPU_DEVID GOT_YOU_MORON
+#define IRQ_NO_SOFTIRQ_CALL GOT_YOU_MORON
#undef IRQF_MODIFY_MASK
#define IRQF_MODIFY_MASK GOT_YOU_MORON
@@ -36,6 +38,16 @@ irq_settings_clr_and_set(struct irq_desc *desc, u32 clr, u32 set)
desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK);
}
+static inline bool irq_settings_no_softirq_call(struct irq_desc *desc)
+{
+ return desc->status_use_accessors & _IRQ_NO_SOFTIRQ_CALL;
+}
+
+static inline void irq_settings_set_no_softirq_call(struct irq_desc *desc)
+{
+ desc->status_use_accessors |= _IRQ_NO_SOFTIRQ_CALL;
+}
+
static inline bool irq_settings_is_per_cpu(struct irq_desc *desc)
{
return desc->status_use_accessors & _IRQ_PER_CPU;
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dc813a948be2..d09e0f51d182 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -341,6 +341,11 @@ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
static int __init irqfixup_setup(char *str)
{
+#ifdef CONFIG_PREEMPT_RT_BASE
+ printk(KERN_WARNING "irqfixup boot option not supported "
+ "w/ CONFIG_PREEMPT_RT\n");
+ return 1;
+#endif
irqfixup = 1;
printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
printk(KERN_WARNING "This may impact system performance.\n");
@@ -353,6 +358,11 @@ module_param(irqfixup, int, 0644);
static int __init irqpoll_setup(char *str)
{
+#ifdef CONFIG_PREEMPT_RT_BASE
+ printk(KERN_WARNING "irqpoll boot option not supported "
+ "w/ CONFIG_PREEMPT_RT\n");
+ return 1;
+#endif
irqfixup = 2;
printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
"enabled\n");