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Diffstat (limited to 'kernel/irq/manage.c')
-rw-r--r--kernel/irq/manage.c38
1 files changed, 17 insertions, 21 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 8c548232ba39..4c69326aa773 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -781,7 +781,7 @@ static void wake_threads_waitq(struct irq_desc *desc)
wake_up(&desc->wait_for_threads);
}
-static void irq_thread_dtor(struct task_work *unused)
+static void irq_thread_dtor(struct callback_head *unused)
{
struct task_struct *tsk = current;
struct irq_desc *desc;
@@ -813,7 +813,7 @@ static void irq_thread_dtor(struct task_work *unused)
*/
static int irq_thread(void *data)
{
- struct task_work on_exit_work;
+ struct callback_head on_exit_work;
static const struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
@@ -830,7 +830,7 @@ static int irq_thread(void *data)
sched_setscheduler(current, SCHED_FIFO, &param);
- init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+ init_task_work(&on_exit_work, irq_thread_dtor);
task_work_add(current, &on_exit_work, false);
while (!irq_wait_for_interrupt(action)) {
@@ -893,22 +893,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
return -ENOSYS;
if (!try_module_get(desc->owner))
return -ENODEV;
- /*
- * 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
@@ -960,6 +944,18 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
}
/*
+ * Drivers are often written to work w/o knowledge about the
+ * underlying irq chip implementation, so a request for a
+ * threaded irq without a primary hard irq context handler
+ * requires the ONESHOT flag to be set. Some irq chips like
+ * MSI based interrupts are per se one shot safe. Check the
+ * chip flags, so we can avoid the unmask dance at the end of
+ * the threaded handler for those.
+ */
+ if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
+ new->flags &= ~IRQF_ONESHOT;
+
+ /*
* The following block of code has to be executed atomically
*/
raw_spin_lock_irqsave(&desc->lock, flags);
@@ -1033,7 +1029,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
new->thread_mask = 1 << ffz(thread_mask);
- } else if (new->handler == irq_default_primary_handler) {
+ } else if (new->handler == irq_default_primary_handler &&
+ !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
/*
* The interrupt was requested with handler = NULL, so
* we use the default primary handler for it. But it
@@ -1354,7 +1351,6 @@ EXPORT_SYMBOL(free_irq);
* Flags:
*
* IRQF_SHARED Interrupt is shared
- * IRQF_SAMPLE_RANDOM The interrupt can be used for entropy
* IRQF_TRIGGER_* Specify active edge(s) or level
*
*/