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

Pull irq fixes from Ingo Molnar:
 "Affinity fixes and a nested threaded IRQ handling fix."

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Always force thread affinity
  irq: Set CPU affinity right on thread creation
  genirq: Provide means to retrigger parent

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 216b0ba109d72f453836568e1aa6c7b7c85e21a6..526f10a637c1fa46989e70f077e8208d67812580 100644 (file)
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -392,6 +392,15 @@ static inline void irq_move_masked_irq(struct irq_data *data) { }
 
 extern int no_irq_affinity;
 
+#ifdef CONFIG_HARDIRQS_SW_RESEND
+int irq_set_parent(int irq, int parent_irq);
+#else
+static inline int irq_set_parent(int irq, int parent_irq)
+{
+       return 0;
+}
+#endif
+
 /*
  * Built-in IRQ handlers for various IRQ types,
  * callable via desc->handle_irq()

diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 0ba014c550565622702a154cf6a6dc78ffabe1fe..623325e2ff97d4f0e3ead2d1eeeeddd35c1916fa 100644 (file)
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -11,6 +11,8 @@
 struct irq_affinity_notify;
 struct proc_dir_entry;
 struct module;
+struct irq_desc;
+
 /**
  * struct irq_desc - interrupt descriptor
  * @irq_data:          per irq and chip data passed down to chip functions
@@ -65,6 +67,7 @@ struct irq_desc {
 #ifdef CONFIG_PROC_FS
        struct proc_dir_entry   *dir;
 #endif
+       int                     parent_irq;
        struct module           *owner;
        const char              *name;
 } ____cacheline_internodealigned_in_smp;

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 57d86d07221e33c7863bfe7f789d6a2f129aaa2f..3aca9f29d30ef4c5089ad97740588a31462fd22d 100644 (file)
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -272,6 +272,7 @@ void handle_nested_irq(unsigned int irq)
 
        raw_spin_lock_irq(&desc->lock);
 
+       desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
        kstat_incr_irqs_this_cpu(irq, desc);
 
        action = desc->action;

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 4c69326aa773f6469b7170d66814d7480ea12ea7..35c70c9e24d8f2ec6011800217e3bcd1880d6ca6 100644 (file)
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -616,6 +616,22 @@ 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 +732,7 @@ 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 +747,18 @@ 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
@@ -833,6 +858,8 @@ 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 +963,16 @@ __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)) {

diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 6454db7b6a4d18ae2e4feb67dc7a572a5d8deac4..9065107f083e90e3fbd3c38f2fbc164d11ff2b3c 100644 (file)
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -74,6 +74,14 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
                if (!desc->irq_data.chip->irq_retrigger ||
                    !desc->irq_data.chip->irq_retrigger(&desc->irq_data)) {
 #ifdef CONFIG_HARDIRQS_SW_RESEND
+                       /*
+                        * If the interrupt has a parent irq and runs
+                        * in the thread context of the parent irq,
+                        * retrigger the parent.
+                        */
+                       if (desc->parent_irq &&
+                           irq_settings_is_nested_thread(desc))
+                               irq = desc->parent_irq;
                        /* Set it pending and activate the softirq: */
                        set_bit(irq, irqs_resend);
                        tasklet_schedule(&resend_tasklet);