Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / kernel / irq / manage.c

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0a8e8f0..fa17855 100644 (file)
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -16,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/sched/rt.h>
 #include <linux/task_work.h>
 
 #include "internals.h"
@@ -616,6 +617,22 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
        return ret;
 }
 
+#ifdef CONFIG_HARDIRQS_SW_RESEND
+int irq_set_parent(int irq, int parent_irq)
+{
+       unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+       if (!desc)
+               return -EINVAL;
+
+       desc->parent_irq = parent_irq;
+
+       irq_put_desc_unlock(desc, flags);
+       return 0;
+}
+#endif
+
 /*
  * Default primary interrupt handler for threaded interrupts. Is
  * assigned as primary handler when request_threaded_irq is called
@@ -716,6 +733,7 @@ static void
 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
 {
        cpumask_var_t mask;
+       bool valid = true;
 
        if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
                return;
@@ -730,10 +748,18 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
        }
 
        raw_spin_lock_irq(&desc->lock);
-       cpumask_copy(mask, desc->irq_data.affinity);
+       /*
+        * This code is triggered unconditionally. Check the affinity
+        * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
+        */
+       if (desc->irq_data.affinity)
+               cpumask_copy(mask, desc->irq_data.affinity);
+       else
+               valid = false;
        raw_spin_unlock_irq(&desc->lock);
 
-       set_cpus_allowed_ptr(current, mask);
+       if (valid)
+               set_cpus_allowed_ptr(current, mask);
        free_cpumask_var(mask);
 }
 #else
@@ -793,7 +819,7 @@ static void irq_thread_dtor(struct callback_head *unused)
        action = kthread_data(tsk);
 
        pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
-              tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
+              tsk->comm, tsk->pid, action->irq);
 
 
        desc = irq_to_desc(action->irq);
@@ -833,6 +859,8 @@ static int irq_thread(void *data)
        init_task_work(&on_exit_work, irq_thread_dtor);
        task_work_add(current, &on_exit_work, false);
 
+       irq_thread_check_affinity(desc, action);
+
        while (!irq_wait_for_interrupt(action)) {
                irqreturn_t action_ret;
 
@@ -936,6 +964,16 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                 */
                get_task_struct(t);
                new->thread = t;
+               /*
+                * Tell the thread to set its affinity. This is
+                * important for shared interrupt handlers as we do
+                * not invoke setup_affinity() for the secondary
+                * handlers as everything is already set up. Even for
+                * interrupts marked with IRQF_NO_BALANCE this is
+                * correct as we want the thread to move to the cpu(s)
+                * on which the requesting code placed the interrupt.
+                */
+               set_bit(IRQTF_AFFINITY, &new->thread_flags);
        }
 
        if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
@@ -943,6 +981,18 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                goto out_thread;
        }
 
+       /*
+        * 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
         */
@@ -1017,7 +1067,8 @@ __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
@@ -1474,6 +1525,7 @@ void enable_percpu_irq(unsigned int irq, unsigned int type)
 out:
        irq_put_desc_unlock(desc, flags);
 }
+EXPORT_SYMBOL_GPL(enable_percpu_irq);
 
 void disable_percpu_irq(unsigned int irq)
 {
@@ -1487,6 +1539,7 @@ void disable_percpu_irq(unsigned int irq)
        irq_percpu_disable(desc, cpu);
        irq_put_desc_unlock(desc, flags);
 }
+EXPORT_SYMBOL_GPL(disable_percpu_irq);
 
 /*
  * Internal function to unregister a percpu irqaction.