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-rw-r--r--kernel/irq/Makefile1
-rw-r--r--kernel/irq/chip.c7
-rw-r--r--kernel/irq/handle.c36
-rw-r--r--kernel/irq/internals.h3
-rw-r--r--kernel/irq/manage.c223
-rw-r--r--kernel/irq/numa_migrate.c11
-rw-r--r--kernel/irq/pm.c79
-rw-r--r--kernel/irq/spurious.c14
8 files changed, 262 insertions, 112 deletions
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 4dd5b1edac98..3394f8f52964 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
obj-$(CONFIG_NUMA_MIGRATE_IRQ_DESC) += numa_migrate.o
+obj-$(CONFIG_PM_SLEEP) += pm.o
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 122fef4b0bd3..c687ba4363f2 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -81,6 +81,7 @@ void dynamic_irq_cleanup(unsigned int irq)
desc->handle_irq = handle_bad_irq;
desc->chip = &no_irq_chip;
desc->name = NULL;
+ clear_kstat_irqs(desc);
spin_unlock_irqrestore(&desc->lock, flags);
}
@@ -293,7 +294,8 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
desc->chip->mask_ack(irq);
else {
desc->chip->mask(irq);
- desc->chip->ack(irq);
+ if (desc->chip->ack)
+ desc->chip->ack(irq);
}
}
@@ -479,7 +481,8 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
kstat_incr_irqs_this_cpu(irq, desc);
/* Start handling the irq */
- desc->chip->ack(irq);
+ if (desc->chip->ack)
+ desc->chip->ack(irq);
desc = irq_remap_to_desc(irq, desc);
/* Mark the IRQ currently in progress.*/
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 412370ab9a34..343acecae629 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -83,19 +83,21 @@ static struct irq_desc irq_desc_init = {
void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
{
- unsigned long bytes;
- char *ptr;
int node;
-
- /* Compute how many bytes we need per irq and allocate them */
- bytes = nr * sizeof(unsigned int);
+ void *ptr;
node = cpu_to_node(cpu);
- ptr = kzalloc_node(bytes, GFP_ATOMIC, node);
- printk(KERN_DEBUG " alloc kstat_irqs on cpu %d node %d\n", cpu, node);
+ ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), GFP_ATOMIC, node);
- if (ptr)
- desc->kstat_irqs = (unsigned int *)ptr;
+ /*
+ * don't overwite if can not get new one
+ * init_copy_kstat_irqs() could still use old one
+ */
+ if (ptr) {
+ printk(KERN_DEBUG " alloc kstat_irqs on cpu %d node %d\n",
+ cpu, node);
+ desc->kstat_irqs = ptr;
+ }
}
static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
@@ -238,6 +240,7 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
}
};
+static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
int __init early_irq_init(void)
{
struct irq_desc *desc;
@@ -254,6 +257,7 @@ int __init early_irq_init(void)
for (i = 0; i < count; i++) {
desc[i].irq = i;
init_alloc_desc_masks(&desc[i], 0, true);
+ desc[i].kstat_irqs = kstat_irqs_all[i];
}
return arch_early_irq_init();
}
@@ -269,6 +273,11 @@ struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
}
#endif /* !CONFIG_SPARSE_IRQ */
+void clear_kstat_irqs(struct irq_desc *desc)
+{
+ memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
+}
+
/*
* What should we do if we get a hw irq event on an illegal vector?
* Each architecture has to answer this themself.
@@ -345,6 +354,8 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
irqreturn_t ret, retval = IRQ_NONE;
unsigned int status = 0;
+ WARN_ONCE(!in_irq(), "BUG: IRQ handler called from non-hardirq context!");
+
if (!(action->flags & IRQF_DISABLED))
local_irq_enable_in_hardirq();
@@ -366,6 +377,11 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
}
#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
+
+#ifdef CONFIG_ENABLE_WARN_DEPRECATED
+# warning __do_IRQ is deprecated. Please convert to proper flow handlers
+#endif
+
/**
* __do_IRQ - original all in one highlevel IRQ handler
* @irq: the interrupt number
@@ -486,12 +502,10 @@ void early_init_irq_lock_class(void)
}
}
-#ifdef CONFIG_SPARSE_IRQ
unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc = irq_to_desc(irq);
return desc ? desc->kstat_irqs[cpu] : 0;
}
-#endif
EXPORT_SYMBOL(kstat_irqs_cpu);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 40416a81a0f5..01ce20eab38f 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -12,9 +12,12 @@ extern void compat_irq_chip_set_default_handler(struct irq_desc *desc);
extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
unsigned long flags);
+extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp);
+extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
extern struct lock_class_key irq_desc_lock_class;
extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
+extern void clear_kstat_irqs(struct irq_desc *desc);
extern spinlock_t sparse_irq_lock;
#ifdef CONFIG_SPARSE_IRQ
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index a3a5dc9ef346..1516ab77355c 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -109,7 +109,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
/*
* Generic version of the affinity autoselector.
*/
-int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
+static int setup_affinity(unsigned int irq, struct irq_desc *desc)
{
if (!irq_can_set_affinity(irq))
return 0;
@@ -133,7 +133,7 @@ set_affinity:
return 0;
}
#else
-static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
{
return irq_select_affinity(irq);
}
@@ -149,19 +149,33 @@ int irq_select_affinity_usr(unsigned int irq)
int ret;
spin_lock_irqsave(&desc->lock, flags);
- ret = do_irq_select_affinity(irq, desc);
+ ret = setup_affinity(irq, desc);
spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
#else
-static inline int do_irq_select_affinity(int irq, struct irq_desc *desc)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
{
return 0;
}
#endif
+void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
+{
+ if (suspend) {
+ if (!desc->action || (desc->action->flags & IRQF_TIMER))
+ return;
+ desc->status |= IRQ_SUSPENDED;
+ }
+
+ if (!desc->depth++) {
+ desc->status |= IRQ_DISABLED;
+ desc->chip->disable(irq);
+ }
+}
+
/**
* disable_irq_nosync - disable an irq without waiting
* @irq: Interrupt to disable
@@ -182,10 +196,7 @@ void disable_irq_nosync(unsigned int irq)
return;
spin_lock_irqsave(&desc->lock, flags);
- if (!desc->depth++) {
- desc->status |= IRQ_DISABLED;
- desc->chip->disable(irq);
- }
+ __disable_irq(desc, irq, false);
spin_unlock_irqrestore(&desc->lock, flags);
}
EXPORT_SYMBOL(disable_irq_nosync);
@@ -215,15 +226,21 @@ void disable_irq(unsigned int irq)
}
EXPORT_SYMBOL(disable_irq);
-static void __enable_irq(struct irq_desc *desc, unsigned int irq)
+void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
{
+ if (resume)
+ desc->status &= ~IRQ_SUSPENDED;
+
switch (desc->depth) {
case 0:
+ err_out:
WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
break;
case 1: {
unsigned int status = desc->status & ~IRQ_DISABLED;
+ if (desc->status & IRQ_SUSPENDED)
+ goto err_out;
/* Prevent probing on this irq: */
desc->status = status | IRQ_NOPROBE;
check_irq_resend(desc, irq);
@@ -253,7 +270,7 @@ void enable_irq(unsigned int irq)
return;
spin_lock_irqsave(&desc->lock, flags);
- __enable_irq(desc, irq);
+ __enable_irq(desc, irq, false);
spin_unlock_irqrestore(&desc->lock, flags);
}
EXPORT_SYMBOL(enable_irq);
@@ -389,9 +406,9 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
* allocate special interrupts that are part of the architecture.
*/
static int
-__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
+__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
{
- struct irqaction *old, **p;
+ struct irqaction *old, **old_ptr;
const char *old_name = NULL;
unsigned long flags;
int shared = 0;
@@ -423,8 +440,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
* The following block of code has to be executed atomically
*/
spin_lock_irqsave(&desc->lock, flags);
- p = &desc->action;
- old = *p;
+ old_ptr = &desc->action;
+ old = *old_ptr;
if (old) {
/*
* Can't share interrupts unless both agree to and are
@@ -447,8 +464,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
/* add new interrupt at end of irq queue */
do {
- p = &old->next;
- old = *p;
+ old_ptr = &old->next;
+ old = *old_ptr;
} while (old);
shared = 1;
}
@@ -488,7 +505,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
desc->status |= IRQ_NO_BALANCING;
/* Set default affinity mask once everything is setup */
- do_irq_select_affinity(irq, desc);
+ setup_affinity(irq, desc);
} else if ((new->flags & IRQF_TRIGGER_MASK)
&& (new->flags & IRQF_TRIGGER_MASK)
@@ -499,7 +516,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
(int)(new->flags & IRQF_TRIGGER_MASK));
}
- *p = new;
+ *old_ptr = new;
/* Reset broken irq detection when installing new handler */
desc->irq_count = 0;
@@ -511,7 +528,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
*/
if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
desc->status &= ~IRQ_SPURIOUS_DISABLED;
- __enable_irq(desc, irq);
+ __enable_irq(desc, irq, false);
}
spin_unlock_irqrestore(&desc->lock, flags);
@@ -549,90 +566,117 @@ int setup_irq(unsigned int irq, struct irqaction *act)
return __setup_irq(irq, desc, act);
}
+EXPORT_SYMBOL_GPL(setup_irq);
-/**
- * free_irq - free an interrupt
- * @irq: Interrupt line to free
- * @dev_id: Device identity to free
- *
- * Remove an interrupt handler. The handler is removed and if the
- * interrupt line is no longer in use by any driver it is disabled.
- * On a shared IRQ the caller must ensure the interrupt is disabled
- * on the card it drives before calling this function. The function
- * does not return until any executing interrupts for this IRQ
- * have completed.
- *
- * This function must not be called from interrupt context.
+ /*
+ * Internal function to unregister an irqaction - used to free
+ * regular and special interrupts that are part of the architecture.
*/
-void free_irq(unsigned int irq, void *dev_id)
+static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
{
struct irq_desc *desc = irq_to_desc(irq);
- struct irqaction **p;
+ struct irqaction *action, **action_ptr;
unsigned long flags;
- WARN_ON(in_interrupt());
+ WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
if (!desc)
- return;
+ return NULL;
spin_lock_irqsave(&desc->lock, flags);
- p = &desc->action;
+
+ /*
+ * There can be multiple actions per IRQ descriptor, find the right
+ * one based on the dev_id:
+ */
+ action_ptr = &desc->action;
for (;;) {
- struct irqaction *action = *p;
+ action = *action_ptr;
- if (action) {
- struct irqaction **pp = p;
+ if (!action) {
+ WARN(1, "Trying to free already-free IRQ %d\n", irq);
+ spin_unlock_irqrestore(&desc->lock, flags);
- p = &action->next;
- if (action->dev_id != dev_id)
- continue;
+ return NULL;
+ }
- /* Found it - now remove it from the list of entries */
- *pp = action->next;
+ if (action->dev_id == dev_id)
+ break;
+ action_ptr = &action->next;
+ }
- /* Currently used only by UML, might disappear one day.*/
+ /* Found it - now remove it from the list of entries: */
+ *action_ptr = action->next;
+
+ /* Currently used only by UML, might disappear one day: */
#ifdef CONFIG_IRQ_RELEASE_METHOD
- if (desc->chip->release)
- desc->chip->release(irq, dev_id);
+ if (desc->chip->release)
+ desc->chip->release(irq, dev_id);
#endif
- if (!desc->action) {
- desc->status |= IRQ_DISABLED;
- if (desc->chip->shutdown)
- desc->chip->shutdown(irq);
- else
- desc->chip->disable(irq);
- }
- spin_unlock_irqrestore(&desc->lock, flags);
- unregister_handler_proc(irq, action);
+ /* If this was the last handler, shut down the IRQ line: */
+ if (!desc->action) {
+ desc->status |= IRQ_DISABLED;
+ if (desc->chip->shutdown)
+ desc->chip->shutdown(irq);
+ else
+ desc->chip->disable(irq);
+ }
+ spin_unlock_irqrestore(&desc->lock, flags);
+
+ unregister_handler_proc(irq, action);
+
+ /* Make sure it's not being used on another CPU: */
+ synchronize_irq(irq);
- /* Make sure it's not being used on another CPU */
- synchronize_irq(irq);
-#ifdef CONFIG_DEBUG_SHIRQ
- /*
- * It's a shared IRQ -- the driver ought to be
- * prepared for it to happen even now it's
- * being freed, so let's make sure.... We do
- * this after actually deregistering it, to
- * make sure that a 'real' IRQ doesn't run in
- * parallel with our fake
- */
- if (action->flags & IRQF_SHARED) {
- local_irq_save(flags);
- action->handler(irq, dev_id);
- local_irq_restore(flags);
- }
-#endif
- kfree(action);
- return;
- }
- printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
#ifdef CONFIG_DEBUG_SHIRQ
- dump_stack();
-#endif
- spin_unlock_irqrestore(&desc->lock, flags);
- return;
+ /*
+ * It's a shared IRQ -- the driver ought to be prepared for an IRQ
+ * event to happen even now it's being freed, so let's make sure that
+ * is so by doing an extra call to the handler ....
+ *
+ * ( We do this after actually deregistering it, to make sure that a
+ * 'real' IRQ doesn't run in * parallel with our fake. )
+ */
+ if (action->flags & IRQF_SHARED) {
+ local_irq_save(flags);
+ action->handler(irq, dev_id);
+ local_irq_restore(flags);
}
+#endif
+ return action;
+}
+
+/**
+ * remove_irq - free an interrupt
+ * @irq: Interrupt line to free
+ * @act: irqaction for the interrupt
+ *
+ * Used to remove interrupts statically setup by the early boot process.
+ */
+void remove_irq(unsigned int irq, struct irqaction *act)
+{
+ __free_irq(irq, act->dev_id);
+}
+EXPORT_SYMBOL_GPL(remove_irq);
+
+/**
+ * free_irq - free an interrupt allocated with request_irq
+ * @irq: Interrupt line to free
+ * @dev_id: Device identity to free
+ *
+ * Remove an interrupt handler. The handler is removed and if the
+ * interrupt line is no longer in use by any driver it is disabled.
+ * On a shared IRQ the caller must ensure the interrupt is disabled
+ * on the card it drives before calling this function. The function
+ * does not return until any executing interrupts for this IRQ
+ * have completed.
+ *
+ * This function must not be called from interrupt context.
+ */
+void free_irq(unsigned int irq, void *dev_id)
+{
+ kfree(__free_irq(irq, dev_id));
}
EXPORT_SYMBOL(free_irq);
@@ -679,11 +723,12 @@ int request_irq(unsigned int irq, irq_handler_t handler,
* the behavior is classified as "will not fix" so we need to
* start nudging drivers away from using that idiom.
*/
- if ((irqflags & (IRQF_SHARED|IRQF_DISABLED))
- == (IRQF_SHARED|IRQF_DISABLED))
- pr_warning("IRQ %d/%s: IRQF_DISABLED is not "
- "guaranteed on shared IRQs\n",
- irq, devname);
+ if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
+ (IRQF_SHARED|IRQF_DISABLED)) {
+ pr_warning(
+ "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
+ irq, devname);
+ }
#ifdef CONFIG_LOCKDEP
/*
@@ -709,15 +754,13 @@ int request_irq(unsigned int irq, irq_handler_t handler,
if (!handler)
return -EINVAL;
- action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
if (!action)
return -ENOMEM;
action->handler = handler;
action->flags = irqflags;
- cpus_clear(action->mask);
action->name = devname;
- action->next = NULL;
action->dev_id = dev_id;
retval = __setup_irq(irq, desc, action);
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
index 7f9b80434e32..243d6121e50e 100644
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -17,16 +17,11 @@ static void init_copy_kstat_irqs(struct irq_desc *old_desc,
struct irq_desc *desc,
int cpu, int nr)
{
- unsigned long bytes;
-
init_kstat_irqs(desc, cpu, nr);
- if (desc->kstat_irqs != old_desc->kstat_irqs) {
- /* Compute how many bytes we need per irq and allocate them */
- bytes = nr * sizeof(unsigned int);
-
- memcpy(desc->kstat_irqs, old_desc->kstat_irqs, bytes);
- }
+ if (desc->kstat_irqs != old_desc->kstat_irqs)
+ memcpy(desc->kstat_irqs, old_desc->kstat_irqs,
+ nr * sizeof(*desc->kstat_irqs));
}
static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
new file mode 100644
index 000000000000..638d8bedec14
--- /dev/null
+++ b/kernel/irq/pm.c
@@ -0,0 +1,79 @@
+/*
+ * linux/kernel/irq/pm.c
+ *
+ * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
+ *
+ * This file contains power management functions related to interrupts.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+
+#include "internals.h"
+
+/**
+ * suspend_device_irqs - disable all currently enabled interrupt lines
+ *
+ * During system-wide suspend or hibernation device interrupts need to be
+ * disabled at the chip level and this function is provided for this purpose.
+ * It disables all interrupt lines that are enabled at the moment and sets the
+ * IRQ_SUSPENDED flag for them.
+ */
+void suspend_device_irqs(void)
+{
+ struct irq_desc *desc;
+ int irq;
+
+ for_each_irq_desc(irq, desc) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&desc->lock, flags);
+ __disable_irq(desc, irq, true);
+ spin_unlock_irqrestore(&desc->lock, flags);
+ }
+
+ for_each_irq_desc(irq, desc)
+ if (desc->status & IRQ_SUSPENDED)
+ synchronize_irq(irq);
+}
+EXPORT_SYMBOL_GPL(suspend_device_irqs);
+
+/**
+ * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
+ *
+ * Enable all interrupt lines previously disabled by suspend_device_irqs() that
+ * have the IRQ_SUSPENDED flag set.
+ */
+void resume_device_irqs(void)
+{
+ struct irq_desc *desc;
+ int irq;
+
+ for_each_irq_desc(irq, desc) {
+ unsigned long flags;
+
+ if (!(desc->status & IRQ_SUSPENDED))
+ continue;
+
+ spin_lock_irqsave(&desc->lock, flags);
+ __enable_irq(desc, irq, true);
+ spin_unlock_irqrestore(&desc->lock, flags);
+ }
+}
+EXPORT_SYMBOL_GPL(resume_device_irqs);
+
+/**
+ * check_wakeup_irqs - check if any wake-up interrupts are pending
+ */
+int check_wakeup_irqs(void)
+{
+ struct irq_desc *desc;
+ int irq;
+
+ for_each_irq_desc(irq, desc)
+ if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING))
+ return -EBUSY;
+
+ return 0;
+}
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dd364c11e56e..4d568294de3e 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -104,7 +104,7 @@ static int misrouted_irq(int irq)
return ok;
}
-static void poll_spurious_irqs(unsigned long dummy)
+static void poll_all_shared_irqs(void)
{
struct irq_desc *desc;
int i;
@@ -123,11 +123,23 @@ static void poll_spurious_irqs(unsigned long dummy)
try_one_irq(i, desc);
}
+}
+
+static void poll_spurious_irqs(unsigned long dummy)
+{
+ poll_all_shared_irqs();
mod_timer(&poll_spurious_irq_timer,
jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
}
+#ifdef CONFIG_DEBUG_SHIRQ
+void debug_poll_all_shared_irqs(void)
+{
+ poll_all_shared_irqs();
+}
+#endif
+
/*
* If 99,900 of the previous 100,000 interrupts have not been handled
* then assume that the IRQ is stuck in some manner. Drop a diagnostic