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authorLinus Torvalds <torvalds@linux-foundation.org>2014-06-04 15:59:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-04 15:59:13 -0700
commitd09cc3659db494aca4b3bb2393c533fb4946b794 (patch)
tree158d1dd5fa5fddf1c99da677a193b8561c11274d /kernel
parent82e627eb5e07d7993216c9e63fb5550cf6ed25d7 (diff)
parentc0ffa793994a7a69c37a96dabf38323eae1dffa6 (diff)
downloadlinux-d09cc3659db494aca4b3bb2393c533fb4946b794.tar.bz2
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core irq updates from Thomas Gleixner: "The irq department delivers: - Another tree wide update to get rid of the horrible create_irq interface along with its even more horrible variants. That also gets rid of the last leftovers of the initial sparse irq hackery. arch/driver specific changes have been either acked or ignored. - A fix for the spurious interrupt detection logic with threaded interrupts. - A new ARM SoC interrupt controller - The usual pile of fixes and improvements all over the place" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) Documentation: brcmstb-l2: Add Broadcom STB Level-2 interrupt controller binding irqchip: brcmstb-l2: Add Broadcom Set Top Box Level-2 interrupt controller genirq: Improve documentation to match current implementation ARM: iop13xx: fix msi support with sparse IRQ genirq: Provide !SMP stub for irq_set_affinity_notifier() irqchip: armada-370-xp: Move the devicetree binding documentation irqchip: gic: Use mask field in GICC_IAR genirq: Remove dynamic_irq mess ia64: Use irq_init_desc genirq: Replace dynamic_irq_init/cleanup genirq: Remove irq_reserve_irq[s] genirq: Replace reserve_irqs in core code s390: Avoid call to irq_reserve_irqs() s390: Remove pointless arch_show_interrupts() s390: pci: Check return value of alloc_irq_desc() proper sh: intc: Remove pointless irq_reserve_irqs() invocation x86, irq: Remove pointless irq_reserve_irqs() call genirq: Make create/destroy_irq() ia64 private tile: Use SPARSE_IRQ tile: pci: Use irq_alloc/free_hwirq() ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/irq/Kconfig9
-rw-r--r--kernel/irq/chip.c5
-rw-r--r--kernel/irq/internals.h8
-rw-r--r--kernel/irq/irqdesc.c95
-rw-r--r--kernel/irq/irqdomain.c6
-rw-r--r--kernel/irq/manage.c4
-rw-r--r--kernel/irq/spurious.c106
7 files changed, 188 insertions, 45 deletions
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 07cbdfea9ae2..d269cecdfbf0 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -5,6 +5,10 @@ menu "IRQ subsystem"
config MAY_HAVE_SPARSE_IRQ
bool
+# Legacy support, required for itanic
+config GENERIC_IRQ_LEGACY
+ bool
+
# Enable the generic irq autoprobe mechanism
config GENERIC_IRQ_PROBE
bool
@@ -17,6 +21,11 @@ config GENERIC_IRQ_SHOW
config GENERIC_IRQ_SHOW_LEVEL
bool
+# Facility to allocate a hardware interrupt. This is legacy support
+# and should not be used in new code. Use irq domains instead.
+config GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
+ bool
+
# Support for delayed migration from interrupt context
config GENERIC_PENDING_IRQ
bool
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 6397df2d6945..a2b28a2fd7b1 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -40,10 +40,9 @@ int irq_set_chip(unsigned int irq, struct irq_chip *chip)
irq_put_desc_unlock(desc, flags);
/*
* For !CONFIG_SPARSE_IRQ make the irq show up in
- * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is
- * already marked, and this call is harmless.
+ * allocated_irqs.
*/
- irq_reserve_irq(irq);
+ irq_mark_irq(irq);
return 0;
}
EXPORT_SYMBOL(irq_set_chip);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index ddf1ffeb79f1..099ea2e0eb88 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -33,7 +33,7 @@ enum {
};
/*
- * Bit masks for desc->state
+ * Bit masks for desc->core_internal_state__do_not_mess_with_it
*
* IRQS_AUTODETECT - autodetection in progress
* IRQS_SPURIOUS_DISABLED - was disabled due to spurious interrupt
@@ -76,6 +76,12 @@ extern void mask_irq(struct irq_desc *desc);
extern void unmask_irq(struct irq_desc *desc);
extern void unmask_threaded_irq(struct irq_desc *desc);
+#ifdef CONFIG_SPARSE_IRQ
+static inline void irq_mark_irq(unsigned int irq) { }
+#else
+extern void irq_mark_irq(unsigned int irq);
+#endif
+
extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action);
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index bb07f2928f4b..7339e42a85ab 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -278,7 +278,12 @@ EXPORT_SYMBOL(irq_to_desc);
static void free_desc(unsigned int irq)
{
- dynamic_irq_cleanup(irq);
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc_set_defaults(irq, desc, desc_node(desc), NULL);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
}
static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
@@ -299,6 +304,20 @@ static int irq_expand_nr_irqs(unsigned int nr)
return -ENOMEM;
}
+void irq_mark_irq(unsigned int irq)
+{
+ mutex_lock(&sparse_irq_lock);
+ bitmap_set(allocated_irqs, irq, 1);
+ mutex_unlock(&sparse_irq_lock);
+}
+
+#ifdef CONFIG_GENERIC_IRQ_LEGACY
+void irq_init_desc(unsigned int irq)
+{
+ free_desc(irq);
+}
+#endif
+
#endif /* !CONFIG_SPARSE_IRQ */
/**
@@ -396,30 +415,56 @@ err:
}
EXPORT_SYMBOL_GPL(__irq_alloc_descs);
+#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
/**
- * irq_reserve_irqs - mark irqs allocated
- * @from: mark from irq number
- * @cnt: number of irqs to mark
+ * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
+ * @cnt: number of interrupts to allocate
+ * @node: node on which to allocate
*
- * Returns 0 on success or an appropriate error code
+ * Returns an interrupt number > 0 or 0, if the allocation fails.
*/
-int irq_reserve_irqs(unsigned int from, unsigned int cnt)
+unsigned int irq_alloc_hwirqs(int cnt, int node)
{
- unsigned int start;
- int ret = 0;
+ int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL);
- if (!cnt || (from + cnt) > nr_irqs)
- return -EINVAL;
+ if (irq < 0)
+ return 0;
- mutex_lock(&sparse_irq_lock);
- start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
- if (start == from)
- bitmap_set(allocated_irqs, start, cnt);
- else
- ret = -EEXIST;
- mutex_unlock(&sparse_irq_lock);
- return ret;
+ for (i = irq; cnt > 0; i++, cnt--) {
+ if (arch_setup_hwirq(i, node))
+ goto err;
+ irq_clear_status_flags(i, _IRQ_NOREQUEST);
+ }
+ return irq;
+
+err:
+ for (i--; i >= irq; i--) {
+ irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
+ arch_teardown_hwirq(i);
+ }
+ irq_free_descs(irq, cnt);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
+
+/**
+ * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
+ * @from: Free from irq number
+ * @cnt: number of interrupts to free
+ *
+ */
+void irq_free_hwirqs(unsigned int from, int cnt)
+{
+ int i;
+
+ for (i = from; cnt > 0; i++, cnt--) {
+ irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
+ arch_teardown_hwirq(i);
+ }
+ irq_free_descs(from, cnt);
}
+EXPORT_SYMBOL_GPL(irq_free_hwirqs);
+#endif
/**
* irq_get_next_irq - get next allocated irq number
@@ -482,20 +527,6 @@ int irq_set_percpu_devid(unsigned int irq)
return 0;
}
-/**
- * dynamic_irq_cleanup - cleanup a dynamically allocated irq
- * @irq: irq number to initialize
- */
-void dynamic_irq_cleanup(unsigned int irq)
-{
- struct irq_desc *desc = irq_to_desc(irq);
- unsigned long flags;
-
- raw_spin_lock_irqsave(&desc->lock, flags);
- desc_set_defaults(irq, desc, desc_node(desc), NULL);
- raw_spin_unlock_irqrestore(&desc->lock, flags);
-}
-
void kstat_incr_irq_this_cpu(unsigned int irq)
{
kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index f14033700c25..eb5e10e32e05 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -27,14 +27,14 @@ static struct irq_domain *irq_default_domain;
* __irq_domain_add() - Allocate a new irq_domain data structure
* @of_node: optional device-tree node of the interrupt controller
* @size: Size of linear map; 0 for radix mapping only
+ * @hwirq_max: Maximum number of interrupts supported by controller
* @direct_max: Maximum value of direct maps; Use ~0 for no limit; 0 for no
* direct mapping
* @ops: map/unmap domain callbacks
* @host_data: Controller private data pointer
*
- * Allocates and initialize and irq_domain structure. Caller is expected to
- * register allocated irq_domain with irq_domain_register(). Returns pointer
- * to IRQ domain, or NULL on failure.
+ * Allocates and initialize and irq_domain structure.
+ * Returns pointer to IRQ domain, or NULL on failure.
*/
struct irq_domain *__irq_domain_add(struct device_node *of_node, int size,
irq_hw_number_t hwirq_max, int direct_max,
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index d34131ca372b..3dc6a61bf06a 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -886,8 +886,8 @@ static int irq_thread(void *data)
irq_thread_check_affinity(desc, action);
action_ret = handler_fn(desc, action);
- if (!noirqdebug)
- note_interrupt(action->irq, desc, action_ret);
+ if (action_ret == IRQ_HANDLED)
+ atomic_inc(&desc->threads_handled);
wake_threads_waitq(desc);
}
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index a1d8cc63b56e..e2514b0e439e 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -270,6 +270,8 @@ try_misrouted_irq(unsigned int irq, struct irq_desc *desc,
return action && (action->flags & IRQF_IRQPOLL);
}
+#define SPURIOUS_DEFERRED 0x80000000
+
void note_interrupt(unsigned int irq, struct irq_desc *desc,
irqreturn_t action_ret)
{
@@ -277,15 +279,111 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
irq_settings_is_polled(desc))
return;
- /* we get here again via the threaded handler */
- if (action_ret == IRQ_WAKE_THREAD)
- return;
-
if (bad_action_ret(action_ret)) {
report_bad_irq(irq, desc, action_ret);
return;
}
+ /*
+ * We cannot call note_interrupt from the threaded handler
+ * because we need to look at the compound of all handlers
+ * (primary and threaded). Aside of that in the threaded
+ * shared case we have no serialization against an incoming
+ * hardware interrupt while we are dealing with a threaded
+ * result.
+ *
+ * So in case a thread is woken, we just note the fact and
+ * defer the analysis to the next hardware interrupt.
+ *
+ * The threaded handlers store whether they sucessfully
+ * handled an interrupt and we check whether that number
+ * changed versus the last invocation.
+ *
+ * We could handle all interrupts with the delayed by one
+ * mechanism, but for the non forced threaded case we'd just
+ * add pointless overhead to the straight hardirq interrupts
+ * for the sake of a few lines less code.
+ */
+ if (action_ret & IRQ_WAKE_THREAD) {
+ /*
+ * There is a thread woken. Check whether one of the
+ * shared primary handlers returned IRQ_HANDLED. If
+ * not we defer the spurious detection to the next
+ * interrupt.
+ */
+ if (action_ret == IRQ_WAKE_THREAD) {
+ int handled;
+ /*
+ * We use bit 31 of thread_handled_last to
+ * denote the deferred spurious detection
+ * active. No locking necessary as
+ * thread_handled_last is only accessed here
+ * and we have the guarantee that hard
+ * interrupts are not reentrant.
+ */
+ if (!(desc->threads_handled_last & SPURIOUS_DEFERRED)) {
+ desc->threads_handled_last |= SPURIOUS_DEFERRED;
+ return;
+ }
+ /*
+ * Check whether one of the threaded handlers
+ * returned IRQ_HANDLED since the last
+ * interrupt happened.
+ *
+ * For simplicity we just set bit 31, as it is
+ * set in threads_handled_last as well. So we
+ * avoid extra masking. And we really do not
+ * care about the high bits of the handled
+ * count. We just care about the count being
+ * different than the one we saw before.
+ */
+ handled = atomic_read(&desc->threads_handled);
+ handled |= SPURIOUS_DEFERRED;
+ if (handled != desc->threads_handled_last) {
+ action_ret = IRQ_HANDLED;
+ /*
+ * Note: We keep the SPURIOUS_DEFERRED
+ * bit set. We are handling the
+ * previous invocation right now.
+ * Keep it for the current one, so the
+ * next hardware interrupt will
+ * account for it.
+ */
+ desc->threads_handled_last = handled;
+ } else {
+ /*
+ * None of the threaded handlers felt
+ * responsible for the last interrupt
+ *
+ * We keep the SPURIOUS_DEFERRED bit
+ * set in threads_handled_last as we
+ * need to account for the current
+ * interrupt as well.
+ */
+ action_ret = IRQ_NONE;
+ }
+ } else {
+ /*
+ * One of the primary handlers returned
+ * IRQ_HANDLED. So we don't care about the
+ * threaded handlers on the same line. Clear
+ * the deferred detection bit.
+ *
+ * In theory we could/should check whether the
+ * deferred bit is set and take the result of
+ * the previous run into account here as
+ * well. But it's really not worth the
+ * trouble. If every other interrupt is
+ * handled we never trigger the spurious
+ * detector. And if this is just the one out
+ * of 100k unhandled ones which is handled
+ * then we merily delay the spurious detection
+ * by one hard interrupt. Not a real problem.
+ */
+ desc->threads_handled_last &= ~SPURIOUS_DEFERRED;
+ }
+ }
+
if (unlikely(action_ret == IRQ_NONE)) {
/*
* If we are seeing only the odd spurious IRQ caused by