]> git.kernelconcepts.de Git - karo-tx-linux.git/blobdiff - kernel/irq/manage.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
[karo-tx-linux.git] / kernel / irq / manage.c
index 4c213864ec458577719602e7c5a93a33d793a6f3..0eebaeef317bc990e3ee1b1bd1719b9e89211685 100644 (file)
@@ -258,37 +258,6 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
 }
 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
 
-/**
- *     irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
- *     @irq: interrupt number to set affinity
- *     @vcpu_info: vCPU specific data
- *
- *     This function uses the vCPU specific data to set the vCPU
- *     affinity for an irq. The vCPU specific data is passed from
- *     outside, such as KVM. One example code path is as below:
- *     KVM -> IOMMU -> irq_set_vcpu_affinity().
- */
-int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
-{
-       unsigned long flags;
-       struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
-       struct irq_data *data;
-       struct irq_chip *chip;
-       int ret = -ENOSYS;
-
-       if (!desc)
-               return -EINVAL;
-
-       data = irq_desc_get_irq_data(desc);
-       chip = irq_data_get_irq_chip(data);
-       if (chip && chip->irq_set_vcpu_affinity)
-               ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
-       irq_put_desc_unlock(desc, flags);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
-
 static void irq_affinity_notify(struct work_struct *work)
 {
        struct irq_affinity_notify *notify =
@@ -424,6 +393,37 @@ setup_affinity(struct irq_desc *desc, struct cpumask *mask)
 }
 #endif
 
+/**
+ *     irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
+ *     @irq: interrupt number to set affinity
+ *     @vcpu_info: vCPU specific data
+ *
+ *     This function uses the vCPU specific data to set the vCPU
+ *     affinity for an irq. The vCPU specific data is passed from
+ *     outside, such as KVM. One example code path is as below:
+ *     KVM -> IOMMU -> irq_set_vcpu_affinity().
+ */
+int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
+{
+       unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+       struct irq_data *data;
+       struct irq_chip *chip;
+       int ret = -ENOSYS;
+
+       if (!desc)
+               return -EINVAL;
+
+       data = irq_desc_get_irq_data(desc);
+       chip = irq_data_get_irq_chip(data);
+       if (chip && chip->irq_set_vcpu_affinity)
+               ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
+       irq_put_desc_unlock(desc, flags);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
+
 void __disable_irq(struct irq_desc *desc)
 {
        if (!desc->depth++)
@@ -730,6 +730,12 @@ static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
        return IRQ_NONE;
 }
 
+static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
+{
+       WARN(1, "Secondary action handler called for irq %d\n", irq);
+       return IRQ_NONE;
+}
+
 static int irq_wait_for_interrupt(struct irqaction *action)
 {
        set_current_state(TASK_INTERRUPTIBLE);
@@ -756,7 +762,8 @@ static int irq_wait_for_interrupt(struct irqaction *action)
 static void irq_finalize_oneshot(struct irq_desc *desc,
                                 struct irqaction *action)
 {
-       if (!(desc->istate & IRQS_ONESHOT))
+       if (!(desc->istate & IRQS_ONESHOT) ||
+           action->handler == irq_forced_secondary_handler)
                return;
 again:
        chip_bus_lock(desc);
@@ -910,6 +917,18 @@ static void irq_thread_dtor(struct callback_head *unused)
        irq_finalize_oneshot(desc, action);
 }
 
+static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
+{
+       struct irqaction *secondary = action->secondary;
+
+       if (WARN_ON_ONCE(!secondary))
+               return;
+
+       raw_spin_lock_irq(&desc->lock);
+       __irq_wake_thread(desc, secondary);
+       raw_spin_unlock_irq(&desc->lock);
+}
+
 /*
  * Interrupt handler thread
  */
@@ -940,6 +959,8 @@ static int irq_thread(void *data)
                action_ret = handler_fn(desc, action);
                if (action_ret == IRQ_HANDLED)
                        atomic_inc(&desc->threads_handled);
+               if (action_ret == IRQ_WAKE_THREAD)
+                       irq_wake_secondary(desc, action);
 
                wake_threads_waitq(desc);
        }
@@ -984,20 +1005,36 @@ void irq_wake_thread(unsigned int irq, void *dev_id)
 }
 EXPORT_SYMBOL_GPL(irq_wake_thread);
 
-static void irq_setup_forced_threading(struct irqaction *new)
+static int irq_setup_forced_threading(struct irqaction *new)
 {
        if (!force_irqthreads)
-               return;
+               return 0;
        if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
-               return;
+               return 0;
 
        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;
+       /*
+        * Handle the case where we have a real primary handler and a
+        * thread handler. We force thread them as well by creating a
+        * secondary action.
+        */
+       if (new->handler != irq_default_primary_handler && new->thread_fn) {
+               /* Allocate the secondary action */
+               new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
+               if (!new->secondary)
+                       return -ENOMEM;
+               new->secondary->handler = irq_forced_secondary_handler;
+               new->secondary->thread_fn = new->thread_fn;
+               new->secondary->dev_id = new->dev_id;
+               new->secondary->irq = new->irq;
+               new->secondary->name = new->name;
        }
+       /* Deal with the primary handler */
+       set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
+       new->thread_fn = new->handler;
+       new->handler = irq_default_primary_handler;
+       return 0;
 }
 
 static int irq_request_resources(struct irq_desc *desc)
@@ -1017,6 +1054,48 @@ static void irq_release_resources(struct irq_desc *desc)
                c->irq_release_resources(d);
 }
 
+static int
+setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
+{
+       struct task_struct *t;
+       struct sched_param param = {
+               .sched_priority = MAX_USER_RT_PRIO/2,
+       };
+
+       if (!secondary) {
+               t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
+                                  new->name);
+       } else {
+               t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
+                                  new->name);
+               param.sched_priority -= 1;
+       }
+
+       if (IS_ERR(t))
+               return PTR_ERR(t);
+
+       sched_setscheduler_nocheck(t, SCHED_FIFO, &param);
+
+       /*
+        * We keep the reference to the task struct even if
+        * the thread dies to avoid that the interrupt code
+        * references an already freed task_struct.
+        */
+       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);
+       return 0;
+}
+
 /*
  * Internal function to register an irqaction - typically used to
  * allocate special interrupts that are part of the architecture.
@@ -1037,6 +1116,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
        if (!try_module_get(desc->owner))
                return -ENODEV;
 
+       new->irq = irq;
+
        /*
         * Check whether the interrupt nests into another interrupt
         * thread.
@@ -1054,8 +1135,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                 */
                new->handler = irq_nested_primary_handler;
        } else {
-               if (irq_settings_can_thread(desc))
-                       irq_setup_forced_threading(new);
+               if (irq_settings_can_thread(desc)) {
+                       ret = irq_setup_forced_threading(new);
+                       if (ret)
+                               goto out_mput;
+               }
        }
 
        /*
@@ -1064,37 +1148,14 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
         * thread.
         */
        if (new->thread_fn && !nested) {
-               struct task_struct *t;
-               static const struct sched_param param = {
-                       .sched_priority = MAX_USER_RT_PRIO/2,
-               };
-
-               t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
-                                  new->name);
-               if (IS_ERR(t)) {
-                       ret = PTR_ERR(t);
+               ret = setup_irq_thread(new, irq, false);
+               if (ret)
                        goto out_mput;
+               if (new->secondary) {
+                       ret = setup_irq_thread(new->secondary, irq, true);
+                       if (ret)
+                               goto out_thread;
                }
-
-               sched_setscheduler_nocheck(t, SCHED_FIFO, &param);
-
-               /*
-                * We keep the reference to the task struct even if
-                * the thread dies to avoid that the interrupt code
-                * references an already freed task_struct.
-                */
-               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)) {
@@ -1267,7 +1328,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                                   irq, nmsk, omsk);
        }
 
-       new->irq = irq;
        *old_ptr = new;
 
        irq_pm_install_action(desc, new);
@@ -1293,6 +1353,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
         */
        if (new->thread)
                wake_up_process(new->thread);
+       if (new->secondary)
+               wake_up_process(new->secondary->thread);
 
        register_irq_proc(irq, desc);
        new->dir = NULL;
@@ -1323,6 +1385,13 @@ out_thread:
                kthread_stop(t);
                put_task_struct(t);
        }
+       if (new->secondary && new->secondary->thread) {
+               struct task_struct *t = new->secondary->thread;
+
+               new->secondary->thread = NULL;
+               kthread_stop(t);
+               put_task_struct(t);
+       }
 out_mput:
        module_put(desc->owner);
        return ret;
@@ -1394,6 +1463,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 
        /* If this was the last handler, shut down the IRQ line: */
        if (!desc->action) {
+               irq_settings_clr_disable_unlazy(desc);
                irq_shutdown(desc);
                irq_release_resources(desc);
        }
@@ -1430,9 +1500,14 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
        if (action->thread) {
                kthread_stop(action->thread);
                put_task_struct(action->thread);
+               if (action->secondary && action->secondary->thread) {
+                       kthread_stop(action->secondary->thread);
+                       put_task_struct(action->secondary->thread);
+               }
        }
 
        module_put(desc->owner);
+       kfree(action->secondary);
        return action;
 }
 
@@ -1576,8 +1651,10 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
        retval = __setup_irq(irq, desc, action);
        chip_bus_sync_unlock(desc);
 
-       if (retval)
+       if (retval) {
+               kfree(action->secondary);
                kfree(action);
+       }
 
 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
        if (!retval && (irqflags & IRQF_SHARED)) {