diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/irq/manage.c | 44 | ||||
| -rw-r--r-- | kernel/sched/core.c | 4 |
2 files changed, 40 insertions, 8 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 32313c08444..0f0d4704ddd 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -985,6 +985,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) /* add new interrupt at end of irq queue */ do { + /* + * Or all existing action->thread_mask bits, + * so we can find the next zero bit for this + * new action. + */ thread_mask |= old->thread_mask; old_ptr = &old->next; old = *old_ptr; @@ -993,14 +998,41 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) } /* - * Setup the thread mask for this irqaction. Unlikely to have - * 32 resp 64 irqs sharing one line, but who knows. + * Setup the thread mask for this irqaction for ONESHOT. For + * !ONESHOT irqs the thread mask is 0 so we can avoid a + * conditional in irq_wake_thread(). */ - if (new->flags & IRQF_ONESHOT && thread_mask == ~0UL) { - ret = -EBUSY; - goto out_mask; + if (new->flags & IRQF_ONESHOT) { + /* + * Unlikely to have 32 resp 64 irqs sharing one line, + * but who knows. + */ + if (thread_mask == ~0UL) { + ret = -EBUSY; + goto out_mask; + } + /* + * The thread_mask for the action is or'ed to + * desc->thread_active to indicate that the + * IRQF_ONESHOT thread handler has been woken, but not + * yet finished. The bit is cleared when a thread + * completes. When all threads of a shared interrupt + * line have completed desc->threads_active becomes + * zero and the interrupt line is unmasked. See + * handle.c:irq_wake_thread() for further information. + * + * If no thread is woken by primary (hard irq context) + * interrupt handlers, then desc->threads_active is + * also checked for zero to unmask the irq line in the + * affected hard irq flow handlers + * (handle_[fasteoi|level]_irq). + * + * The new action gets the first zero bit of + * thread_mask assigned. See the loop above which or's + * all existing action->thread_mask bits. + */ + new->thread_mask = 1 << ffz(thread_mask); } - new->thread_mask = 1 << ffz(thread_mask); if (!shared) { init_waitqueue_head(&desc->wait_for_threads); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 33a0676ea74..b342f57879e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6728,7 +6728,7 @@ int __init sched_create_sysfs_power_savings_entries(struct device *dev) static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { - switch (action) { + switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: cpuset_update_active_cpus(); @@ -6741,7 +6741,7 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, void *hcpu) { - switch (action) { + switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_PREPARE: cpuset_update_active_cpus(); return NOTIFY_OK; |