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authorPaul Mundt <lethal@linux-sh.org>2011-03-17 16:44:08 +0900
committerPaul Mundt <lethal@linux-sh.org>2011-03-17 16:44:08 +0900
commit1d2a1959fe534279cf37aba20b08c24c20840e52 (patch)
tree67c0b9aa7fe22a44bf0b4af88947799203eb8f67 /kernel/irq/manage.c
parent5a79ce76e9bb8f4b2cd8106ee36d15ee05013bcf (diff)
parent054cfaacf88865bff1dd58d305443d5d6c068a08 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into sh-latest
Diffstat (limited to 'kernel/irq/manage.c')
-rw-r--r--kernel/irq/manage.c604
1 files changed, 413 insertions, 191 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0caa59f747d..acd599a43bf 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -17,6 +17,17 @@
#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
@@ -30,7 +41,7 @@
void synchronize_irq(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
- unsigned int status;
+ unsigned int state;
if (!desc)
return;
@@ -42,16 +53,16 @@ void synchronize_irq(unsigned int irq)
* Wait until we're out of the critical section. This might
* give the wrong answer due to the lack of memory barriers.
*/
- while (desc->status & IRQ_INPROGRESS)
+ while (desc->istate & IRQS_INPROGRESS)
cpu_relax();
/* Ok, that indicated we're done: double-check carefully. */
raw_spin_lock_irqsave(&desc->lock, flags);
- status = desc->status;
+ state = desc->istate;
raw_spin_unlock_irqrestore(&desc->lock, flags);
/* Oops, that failed? */
- } while (status & IRQ_INPROGRESS);
+ } while (state & IRQS_INPROGRESS);
/*
* We made sure that no hardirq handler is running. Now verify
@@ -73,8 +84,8 @@ int irq_can_set_affinity(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
- if (CHECK_IRQ_PER_CPU(desc->status) || !desc->irq_data.chip ||
- !desc->irq_data.chip->irq_set_affinity)
+ if (!desc || !irqd_can_balance(&desc->irq_data) ||
+ !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
return 0;
return 1;
@@ -100,67 +111,169 @@ void irq_set_thread_affinity(struct irq_desc *desc)
}
}
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+static inline bool irq_can_move_pcntxt(struct irq_desc *desc)
+{
+ return irq_settings_can_move_pcntxt(desc);
+}
+static inline bool irq_move_pending(struct irq_desc *desc)
+{
+ return irqd_is_setaffinity_pending(&desc->irq_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_desc *desc) { return true; }
+static inline bool irq_move_pending(struct irq_desc *desc) { 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
+
/**
* irq_set_affinity - Set the irq affinity of a given irq
* @irq: Interrupt to set affinity
* @cpumask: cpumask
*
*/
-int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
+int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
{
struct irq_desc *desc = irq_to_desc(irq);
struct irq_chip *chip = desc->irq_data.chip;
unsigned long flags;
+ int ret = 0;
if (!chip->irq_set_affinity)
return -EINVAL;
raw_spin_lock_irqsave(&desc->lock, flags);
-#ifdef CONFIG_GENERIC_PENDING_IRQ
- if (desc->status & IRQ_MOVE_PCNTXT) {
- if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) {
- cpumask_copy(desc->irq_data.affinity, cpumask);
+ if (irq_can_move_pcntxt(desc)) {
+ 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);
+ ret = 0;
}
+ } else {
+ irqd_set_move_pending(&desc->irq_data);
+ irq_copy_pending(desc, mask);
}
- else {
- desc->status |= IRQ_MOVE_PENDING;
- cpumask_copy(desc->pending_mask, cpumask);
- }
-#else
- if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) {
- cpumask_copy(desc->irq_data.affinity, cpumask);
- irq_set_thread_affinity(desc);
+
+ if (desc->affinity_notify) {
+ kref_get(&desc->affinity_notify->kref);
+ schedule_work(&desc->affinity_notify->work);
}
-#endif
- desc->status |= IRQ_AFFINITY_SET;
+ irq_compat_set_affinity(desc);
+ irqd_set(&desc->irq_data, IRQD_AFFINITY_SET);
raw_spin_unlock_irqrestore(&desc->lock, flags);
- return 0;
+ 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_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(&notify->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(&notify->kref);
+ INIT_WORK(&notify->work, irq_affinity_notify);
+ }
+
raw_spin_lock_irqsave(&desc->lock, flags);
- desc->affinity_hint = m;
+ 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_hint);
+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)
+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;
@@ -168,22 +281,29 @@ static int setup_affinity(unsigned int irq, struct irq_desc *desc)
* Preserve an userspace affinity setup, but make sure that
* one of the targets is online.
*/
- if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) {
- if (cpumask_any_and(desc->irq_data.affinity, cpu_online_mask)
- < nr_cpu_ids)
- goto set_affinity;
- else
- desc->status &= ~IRQ_AFFINITY_SET;
+ 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 {
+ irq_compat_clr_affinity(desc);
+ irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
+ }
}
- cpumask_and(desc->irq_data.affinity, cpu_online_mask, irq_default_affinity);
-set_affinity:
- desc->irq_data.chip->irq_set_affinity(&desc->irq_data, desc->irq_data.affinity, false);
-
+ 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)
+static inline int
+setup_affinity(unsigned int irq, struct irq_desc *d, struct cpumask *mask)
{
return irq_select_affinity(irq);
}
@@ -192,23 +312,21 @@ static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
/*
* Called when affinity is set via /proc/irq
*/
-int irq_select_affinity_usr(unsigned int 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);
- if (!ret)
- irq_set_thread_affinity(desc);
+ 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)
+static inline int
+setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
{
return 0;
}
@@ -219,13 +337,23 @@ 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->status |= IRQ_SUSPENDED;
+ desc->istate |= IRQS_SUSPENDED;
}
- if (!desc->depth++) {
- desc->status |= IRQ_DISABLED;
- desc->irq_data.chip->irq_disable(&desc->irq_data);
- }
+ 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;
}
/**
@@ -241,17 +369,7 @@ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
*/
void disable_irq_nosync(unsigned int irq)
{
- struct irq_desc *desc = irq_to_desc(irq);
- unsigned long flags;
-
- if (!desc)
- return;
-
- chip_bus_lock(desc);
- raw_spin_lock_irqsave(&desc->lock, flags);
- __disable_irq(desc, irq, false);
- raw_spin_unlock_irqrestore(&desc->lock, flags);
- chip_bus_sync_unlock(desc);
+ __disable_irq_nosync(irq);
}
EXPORT_SYMBOL(disable_irq_nosync);
@@ -269,21 +387,24 @@ EXPORT_SYMBOL(disable_irq_nosync);
*/
void disable_irq(unsigned int irq)
{
- struct irq_desc *desc = irq_to_desc(irq);
-
- if (!desc)
- return;
-
- disable_irq_nosync(irq);
- if (desc->action)
+ 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)
- desc->status &= ~IRQ_SUSPENDED;
+ 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:
@@ -291,12 +412,11 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
break;
case 1: {
- unsigned int status = desc->status & ~IRQ_DISABLED;
-
- if (desc->status & IRQ_SUSPENDED)
+ if (desc->istate & IRQS_SUSPENDED)
goto err_out;
/* Prevent probing on this irq: */
- desc->status = status | IRQ_NOPROBE;
+ irq_settings_set_noprobe(desc);
+ irq_enable(desc);
check_irq_resend(desc, irq);
/* fall-through */
}
@@ -318,21 +438,18 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
*/
void enable_irq(unsigned int irq)
{
- struct irq_desc *desc = irq_to_desc(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;
- if (WARN(!desc->irq_data.chip || !desc->irq_data.chip->irq_enable,
- KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
- return;
-
- chip_bus_lock(desc);
- raw_spin_lock_irqsave(&desc->lock, flags);
__enable_irq(desc, irq, false);
- raw_spin_unlock_irqrestore(&desc->lock, flags);
- chip_bus_sync_unlock(desc);
+out:
+ irq_put_desc_busunlock(desc, flags);
}
EXPORT_SYMBOL(enable_irq);
@@ -348,7 +465,7 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on)
}
/**
- * set_irq_wake - control irq power management wakeup
+ * irq_set_irq_wake - control irq power management wakeup
* @irq: interrupt to control
* @on: enable/disable power management wakeup
*
@@ -359,23 +476,22 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on)
* Wakeup mode lets this IRQ wake the system from sleep
* states like "suspend to RAM".
*/
-int set_irq_wake(unsigned int irq, unsigned int on)
+int irq_set_irq_wake(unsigned int irq, unsigned int on)
{
- struct irq_desc *desc = irq_to_desc(irq);
unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
int ret = 0;
/* wakeup-capable irqs can be shared between drivers that
* don't need to have the same sleep mode behaviors.
*/
- raw_spin_lock_irqsave(&desc->lock, flags);
if (on) {
if (desc->wake_depth++ == 0) {
ret = set_irq_wake_real(irq, on);
if (ret)
desc->wake_depth = 0;
else
- desc->status |= IRQ_WAKEUP;
+ irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
}
} else {
if (desc->wake_depth == 0) {
@@ -385,14 +501,13 @@ int set_irq_wake(unsigned int irq, unsigned int on)
if (ret)
desc->wake_depth = 1;
else
- desc->status &= ~IRQ_WAKEUP;
+ irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
}
}
-
- raw_spin_unlock_irqrestore(&desc->lock, flags);
+ irq_put_desc_busunlock(desc, flags);
return ret;
}
-EXPORT_SYMBOL(set_irq_wake);
+EXPORT_SYMBOL(irq_set_irq_wake);
/*
* Internal function that tells the architecture code whether a
@@ -401,43 +516,27 @@ EXPORT_SYMBOL(set_irq_wake);
*/
int can_request_irq(unsigned int irq, unsigned long irqflags)
{
- struct irq_desc *desc = irq_to_desc(irq);
- struct irqaction *action;
unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
+ int canrequest = 0;
if (!desc)
return 0;
- if (desc->status & IRQ_NOREQUEST)
- return 0;
-
- raw_spin_lock_irqsave(&desc->lock, flags);
- action = desc->action;
- if (action)
- if (irqflags & action->flags & IRQF_SHARED)
- action = NULL;
-
- raw_spin_unlock_irqrestore(&desc->lock, flags);
-
- return !action;
-}
-
-void compat_irq_chip_set_default_handler(struct irq_desc *desc)
-{
- /*
- * If the architecture still has not overriden
- * the flow handler then zap the default. This
- * should catch incorrect flow-type setting.
- */
- if (desc->handle_irq == &handle_bad_irq)
- desc->handle_irq = NULL;
+ 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)
{
- int ret;
struct irq_chip *chip = desc->irq_data.chip;
+ int ret, unmask = 0;
if (!chip || !chip->irq_set_type) {
/*
@@ -449,23 +548,43 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
return 0;
}
+ flags &= IRQ_TYPE_SENSE_MASK;
+
+ if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
+ if (!(desc->istate & IRQS_MASKED))
+ mask_irq(desc);
+ if (!(desc->istate & IRQS_DISABLED))
+ unmask = 1;
+ }
+
/* caller masked out all except trigger mode flags */
ret = chip->irq_set_type(&desc->irq_data, flags);
- if (ret)
- pr_err("setting trigger mode %lu for irq %u failed (%pF)\n",
- flags, irq, chip->irq_set_type);
- else {
- if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
- flags |= IRQ_LEVEL;
- /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */
- desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK);
- desc->status |= 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);
+ }
if (chip != desc->irq_data.chip)
irq_chip_set_defaults(desc->irq_data.chip);
+ 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;
}
@@ -509,8 +628,11 @@ static int irq_wait_for_interrupt(struct irqaction *action)
* handler finished. unmask if the interrupt has not been disabled and
* is marked MASKED.
*/
-static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
+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);
@@ -522,26 +644,44 @@ again:
* 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 IRQ_INPROGRESS and the irq line is masked forever.
+ * 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(desc->status & IRQ_INPROGRESS)) {
+ if (unlikely(desc->istate & IRQS_INPROGRESS)) {
raw_spin_unlock_irq(&desc->lock);
chip_bus_sync_unlock(desc);
cpu_relax();
goto again;
}
- if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
- desc->status &= ~IRQ_MASKED;
+ /*
+ * 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 && !(desc->istate & IRQS_DISABLED) &&
+ (desc->istate & IRQS_MASKED)) {
+ irq_compat_clr_masked(desc);
+ desc->istate &= ~IRQS_MASKED;
desc->irq_data.chip->irq_unmask(&desc->irq_data);
}
+out_unlock:
raw_spin_unlock_irq(&desc->lock);
chip_bus_sync_unlock(desc);
}
#ifdef CONFIG_SMP
/*
- * Check whether we need to change the affinity of the interrupt thread.
+ * 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)
@@ -573,6 +713,32 @@ 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 void
+irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
+{
+ local_bh_disable();
+ action->thread_fn(action->irq, action->dev_id);
+ irq_finalize_oneshot(desc, action, false);
+ local_bh_enable();
+}
+
+/*
+ * Interrupts explicitely requested as threaded interupts want to be
+ * preemtible - many of them need to sleep and wait for slow busses to
+ * complete.
+ */
+static void irq_thread_fn(struct irq_desc *desc, struct irqaction *action)
+{
+ action->thread_fn(action->irq, action->dev_id);
+ irq_finalize_oneshot(desc, action, false);
+}
+
+/*
* Interrupt handler thread
*/
static int irq_thread(void *data)
@@ -582,7 +748,14 @@ static int irq_thread(void *data)
};
struct irqaction *action = data;
struct irq_desc *desc = irq_to_desc(action->irq);
- int wake, oneshot = desc->status & IRQ_ONESHOT;
+ void (*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, &param);
current->irqaction = action;
@@ -594,23 +767,20 @@ static int irq_thread(void *data)
atomic_inc(&desc->threads_active);
raw_spin_lock_irq(&desc->lock);
- if (unlikely(desc->status & IRQ_DISABLED)) {
+ if (unlikely(desc->istate & IRQS_DISABLED)) {
/*
* CHECKME: We might need a dedicated
* IRQ_THREAD_PENDING flag here, which
* retriggers the thread in check_irq_resend()
- * but AFAICT IRQ_PENDING should be fine as it
+ * but AFAICT IRQS_PENDING should be fine as it
* retriggers the interrupt itself --- tglx
*/
- desc->status |= IRQ_PENDING;
+ irq_compat_set_pending(desc);
+ desc->istate |= IRQS_PENDING;
raw_spin_unlock_irq(&desc->lock);
} else {
raw_spin_unlock_irq(&desc->lock);
-
- action->thread_fn(action->irq, action->dev_id);
-
- if (oneshot)
- irq_finalize_oneshot(action->irq, desc);
+ handler_fn(desc, action);
}
wake = atomic_dec_and_test(&desc->threads_active);
@@ -619,6 +789,9 @@ static int irq_thread(void *data)
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.
@@ -633,6 +806,7 @@ static int irq_thread(void *data)
void exit_irq_thread(void)
{
struct task_struct *tsk = current;
+ struct irq_desc *desc;
if (!tsk->irqaction)
return;
@@ -641,6 +815,14 @@ void exit_irq_thread(void)
"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.
@@ -648,6 +830,22 @@ void exit_irq_thread(void)
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.
@@ -657,9 +855,9 @@ __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;
- int nested, shared = 0;
- int ret;
+ unsigned long flags, thread_mask = 0;
+ int ret, nested, shared = 0;
+ cpumask_var_t mask;
if (!desc)
return -EINVAL;
@@ -683,15 +881,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
rand_initialize_irq(irq);
}
- /* Oneshot interrupts are not allowed with shared */
- if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED))
- return -EINVAL;
-
/*
* Check whether the interrupt nests into another interrupt
* thread.
*/
- nested = desc->status & IRQ_NESTED_THREAD;
+ nested = irq_settings_is_nested_thread(desc);
if (nested) {
if (!new->thread_fn)
return -EINVAL;
@@ -701,6 +895,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* dummy function which warns when called.
*/
new->handler = irq_nested_primary_handler;
+ } else {
+ irq_setup_forced_threading(new);
}
/*
@@ -724,6 +920,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
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
*/
@@ -735,29 +936,40 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* 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.
+ * 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_TRIGGER_MASK) ||
+ ((old->flags ^ new->flags) & IRQF_ONESHOT)) {
old_name = old->name;
goto mismatch;
}
-#if defined(CONFIG_IRQ_PER_CPU)
/* All handlers must agree on per-cpuness */
if ((old->flags & IRQF_PERCPU) !=
(new->flags & IRQF_PERCPU))
goto mismatch;
-#endif
/* add new interrupt at end of irq queue */
do {
+ thread_mask |= old->thread_mask;
old_ptr = &old->next;
old = *old_ptr;
} while (old);
shared = 1;
}
+ /*
+ * Setup the thread mask for this irqaction. Unlikely to have
+ * 32 resp 64 irqs sharing one line, but who knows.
+ */
+ if (new->flags & IRQF_ONESHOT && thread_mask == ~0UL) {
+ ret = -EBUSY;
+ goto out_mask;
+ }
+ new->thread_mask = 1 << ffz(thread_mask);
+
if (!shared) {
irq_chip_set_defaults(desc->irq_data.chip);
@@ -769,42 +981,44 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
new->flags & IRQF_TRIGGER_MASK);
if (ret)
- goto out_thread;
- } else
- compat_irq_chip_set_default_handler(desc);
-#if defined(CONFIG_IRQ_PER_CPU)
- if (new->flags & IRQF_PERCPU)
- desc->status |= IRQ_PER_CPU;
-#endif
+ goto out_mask;
+ }
- desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT |
- IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED);
+ desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
+ IRQS_INPROGRESS | IRQS_ONESHOT | \
+ IRQS_WAITING);
+
+ 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->status |= IRQ_ONESHOT;
+ desc->istate |= IRQS_ONESHOT;
- if (!(desc->status & IRQ_NOAUTOEN)) {
- desc->depth = 0;
- desc->status &= ~IRQ_DISABLED;
- desc->irq_data.chip->irq_startup(&desc->irq_data);
- } else
+ if (irq_settings_can_autoenable(desc))
+ irq_startup(desc);
+ else
/* Undo nested disables: */
desc->depth = 1;
/* Exclude IRQ from balancing if requested */
- if (new->flags & IRQF_NOBALANCING)
- desc->status |= IRQ_NO_BALANCING;
+ 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);
-
- } else if ((new->flags & IRQF_TRIGGER_MASK)
- && (new->flags & IRQF_TRIGGER_MASK)
- != (desc->status & IRQ_TYPE_SENSE_MASK)) {
- /* hope the handler works with the actual trigger mode... */
- pr_warning("IRQ %d uses trigger mode %d; requested %d\n",
- irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK),
- (int)(new->flags & IRQF_TRIGGER_MASK));
+ 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;
@@ -818,8 +1032,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* Check whether we disabled the irq via the spurious handler
* before. Reenable it and give it another chance.
*/
- if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
- desc->status &= ~IRQ_SPURIOUS_DISABLED;
+ if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
+ desc->istate &= ~IRQS_SPURIOUS_DISABLED;
__enable_irq(desc, irq, false);
}
@@ -849,6 +1063,9 @@ mismatch:
#endif
ret = -EBUSY;
+out_mask:
+ free_cpumask_var(mask);
+
out_thread:
raw_spin_unlock_irqrestore(&desc->lock, flags);
if (new->thread) {
@@ -871,9 +1088,14 @@ out_thread:
*/
int setup_irq(unsigned int irq, struct irqaction *act)
{
+ int retval;
struct irq_desc *desc = irq_to_desc(irq);
- return __setup_irq(irq, desc, act);
+ chip_bus_lock(desc);
+ retval = __setup_irq(irq, desc, act);
+ chip_bus_sync_unlock(desc);
+
+ return retval;
}
EXPORT_SYMBOL_GPL(setup_irq);
@@ -924,13 +1146,8 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
#endif
/* If this was the last handler, shut down the IRQ line: */
- if (!desc->action) {
- desc->status |= IRQ_DISABLED;
- if (desc->irq_data.chip->irq_shutdown)
- desc->irq_data.chip->irq_shutdown(&desc->irq_data);
- else
- desc->irq_data.chip->irq_disable(&desc->irq_data);
- }
+ if (!desc->action)
+ irq_shutdown(desc);
#ifdef CONFIG_SMP
/* make sure affinity_hint is cleaned up */
@@ -1004,6 +1221,11 @@ void free_irq(unsigned int irq, void *dev_id)
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);
@@ -1074,7 +1296,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
if (!desc)
return -EINVAL;
- if (desc->status & IRQ_NOREQUEST)
+ if (!irq_settings_can_request(desc))
return -EINVAL;
if (!handler) {
@@ -1100,7 +1322,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
if (retval)
kfree(action);
-#ifdef CONFIG_DEBUG_SHIRQ
+#ifdef CONFIG_DEBUG_SHIRQ_FIXME
if (!retval && (irqflags & IRQF_SHARED)) {
/*
* It's a shared IRQ -- the driver ought to be prepared for it
@@ -1149,7 +1371,7 @@ int request_any_context_irq(unsigned int irq, irq_handler_t handler,
if (!desc)
return -EINVAL;
- if (desc->status & IRQ_NESTED_THREAD) {
+ if (irq_settings_is_nested_thread(desc)) {
ret = request_threaded_irq(irq, NULL, handler,
flags, name, dev_id);
return !ret ? IRQC_IS_NESTED : ret;