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Diffstat (limited to 'kernel/irq/manage.c')
-rw-r--r--kernel/irq/manage.c155
1 files changed, 81 insertions, 74 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0f0d4704ddd8..bb32326afe87 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -282,7 +282,7 @@ 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;
+ int ret, node = desc->irq_data.node;
/* Excludes PER_CPU and NO_BALANCE interrupts */
if (!irq_can_set_affinity(irq))
@@ -301,6 +301,13 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
}
cpumask_and(mask, cpu_online_mask, set);
+ if (node != NUMA_NO_NODE) {
+ const struct cpumask *nodemask = cpumask_of_node(node);
+
+ /* make sure at least one of the cpus in nodemask is online */
+ if (cpumask_intersects(mask, nodemask))
+ cpumask_and(mask, mask, nodemask);
+ }
ret = chip->irq_set_affinity(&desc->irq_data, mask, false);
switch (ret) {
case IRQ_SET_MASK_OK:
@@ -558,8 +565,8 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
* 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");
+ pr_debug("genirq: No set_type function for IRQ %d (%s)\n", irq,
+ chip ? (chip->name ? : "unknown") : "unknown");
return 0;
}
@@ -593,7 +600,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
ret = 0;
break;
default:
- pr_err("setting trigger mode %lu for irq %u failed (%pF)\n",
+ pr_err("genirq: Setting trigger mode %lu for irq %u failed (%pF)\n",
flags, irq, chip->irq_set_type);
}
if (unmask)
@@ -645,7 +652,7 @@ static int irq_wait_for_interrupt(struct irqaction *action)
* is marked MASKED.
*/
static void irq_finalize_oneshot(struct irq_desc *desc,
- struct irqaction *action, bool force)
+ struct irqaction *action)
{
if (!(desc->istate & IRQS_ONESHOT))
return;
@@ -679,7 +686,7 @@ again:
* we would clear the threads_oneshot bit of this thread which
* was just set.
*/
- if (!force && test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
goto out_unlock;
desc->threads_oneshot &= ~action->thread_mask;
@@ -739,7 +746,7 @@ 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);
+ irq_finalize_oneshot(desc, action);
local_bh_enable();
return ret;
}
@@ -755,10 +762,17 @@ static irqreturn_t irq_thread_fn(struct irq_desc *desc,
irqreturn_t ret;
ret = action->thread_fn(action->irq, action->dev_id);
- irq_finalize_oneshot(desc, action, false);
+ irq_finalize_oneshot(desc, action);
return ret;
}
+static void wake_threads_waitq(struct irq_desc *desc)
+{
+ if (atomic_dec_and_test(&desc->threads_active) &&
+ waitqueue_active(&desc->wait_for_threads))
+ wake_up(&desc->wait_for_threads);
+}
+
/*
* Interrupt handler thread
*/
@@ -771,57 +785,41 @@ static int irq_thread(void *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,
+ 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;
+ current->irq_thread = 1;
while (!irq_wait_for_interrupt(action)) {
+ irqreturn_t action_ret;
irq_thread_check_affinity(desc, action);
- atomic_inc(&desc->threads_active);
+ action_ret = handler_fn(desc, action);
+ if (!noirqdebug)
+ note_interrupt(action->irq, desc, action_ret);
- 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);
+ wake_threads_waitq(desc);
}
- /* Prevent a stale desc->threads_oneshot */
- irq_finalize_oneshot(desc, action, true);
-
/*
- * Clear irqaction. Otherwise exit_irq_thread() would make
+ * This is the regular exit path. __free_irq() is stopping the
+ * thread via kthread_stop() after calling
+ * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
+ * oneshot mask bit can be set. We cannot verify that as we
+ * cannot touch the oneshot mask at this point anymore as
+ * __setup_irq() might have given out currents thread_mask
+ * again.
+ *
+ * Clear irq_thread. Otherwise exit_irq_thread() would make
* fuzz about an active irq thread going into nirvana.
*/
- current->irqaction = NULL;
+ current->irq_thread = 0;
return 0;
}
@@ -832,27 +830,27 @@ void exit_irq_thread(void)
{
struct task_struct *tsk = current;
struct irq_desc *desc;
+ struct irqaction *action;
- if (!tsk->irqaction)
+ if (!tsk->irq_thread)
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);
+ action = kthread_data(tsk);
- desc = irq_to_desc(tsk->irqaction->irq);
+ pr_err("genirq: exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
- /*
- * Prevent a stale desc->threads_oneshot. Must be called
- * before setting the IRQTF_DIED flag.
- */
- irq_finalize_oneshot(desc, tsk->irqaction, true);
+ desc = irq_to_desc(action->irq);
/*
- * Set the THREAD DIED flag to prevent further wakeups of the
- * soon to be gone threaded handler.
+ * If IRQTF_RUNTHREAD is set, we need to decrement
+ * desc->threads_active and wake possible waiters.
*/
- set_bit(IRQTF_DIED, &tsk->irqaction->flags);
+ if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ wake_threads_waitq(desc);
+
+ /* Prevent a stale desc->threads_oneshot */
+ irq_finalize_oneshot(desc, action);
}
static void irq_setup_forced_threading(struct irqaction *new)
@@ -879,7 +877,6 @@ 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;
@@ -973,10 +970,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
if (!((old->flags & new->flags) & IRQF_SHARED) ||
((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) ||
- ((old->flags ^ new->flags) & IRQF_ONESHOT)) {
- old_name = old->name;
+ ((old->flags ^ new->flags) & IRQF_ONESHOT))
goto mismatch;
- }
/* All handlers must agree on per-cpuness */
if ((old->flags & IRQF_PERCPU) !=
@@ -1032,6 +1027,27 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* all existing action->thread_mask bits.
*/
new->thread_mask = 1 << ffz(thread_mask);
+
+ } else if (new->handler == irq_default_primary_handler) {
+ /*
+ * The interrupt was requested with handler = NULL, so
+ * we use the default primary handler for it. But it
+ * does not have the oneshot flag set. In combination
+ * with level interrupts this is deadly, because the
+ * default primary handler just wakes the thread, then
+ * the irq lines is reenabled, but the device still
+ * has the level irq asserted. Rinse and repeat....
+ *
+ * While this works for edge type interrupts, we play
+ * it safe and reject unconditionally because we can't
+ * say for sure which type this interrupt really
+ * has. The type flags are unreliable as the
+ * underlying chip implementation can override them.
+ */
+ pr_err("genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
+ irq);
+ ret = -EINVAL;
+ goto out_mask;
}
if (!shared) {
@@ -1079,7 +1095,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
if (nmsk != omsk)
/* hope the handler works with current trigger mode */
- pr_warning("IRQ %d uses trigger mode %u; requested %u\n",
+ pr_warning("genirq: irq %d uses trigger mode %u; requested %u\n",
irq, nmsk, omsk);
}
@@ -1116,14 +1132,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
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);
+ pr_err("genirq: Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
+ irq, new->flags, new->name, old->flags, old->name);
+#ifdef CONFIG_DEBUG_SHIRQ
dump_stack();
- }
#endif
+ }
ret = -EBUSY;
out_mask:
@@ -1135,8 +1150,7 @@ out_thread:
struct task_struct *t = new->thread;
new->thread = NULL;
- if (likely(!test_bit(IRQTF_DIED, &new->thread_flags)))
- kthread_stop(t);
+ kthread_stop(t);
put_task_struct(t);
}
out_mput:
@@ -1206,12 +1220,6 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
/* 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);
@@ -1246,8 +1254,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
#endif
if (action->thread) {
- if (!test_bit(IRQTF_DIED, &action->thread_flags))
- kthread_stop(action->thread);
+ kthread_stop(action->thread);
put_task_struct(action->thread);
}