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-rw-r--r--MAINTAINERS8
-rw-r--r--arch/arm/mach-mvebu/armada-370-xp.h2
-rw-r--r--arch/arm/mach-mvebu/platsmp.c8
-rw-r--r--drivers/irqchip/irq-armada-370-xp.c24
-rw-r--r--drivers/irqchip/irq-orion.c4
-rw-r--r--include/linux/interrupt.h5
-rw-r--r--include/linux/irqdesc.h4
-rw-r--r--kernel/irq/manage.c4
-rw-r--r--kernel/irq/spurious.c106
9 files changed, 145 insertions, 20 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 51ebb779c5f3..b85f6451044f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4818,6 +4818,14 @@ L: linux-kernel@vger.kernel.org
S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core
F: kernel/irq/
+
+IRQCHIP DRIVERS
+M: Thomas Gleixner <tglx@linutronix.de>
+M: Jason Cooper <jason@lakedaemon.net>
+L: linux-kernel@vger.kernel.org
+S: Maintained
+T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core
+T: git git://git.infradead.org/users/jcooper/linux.git irqchip/core
F: drivers/irqchip/
IRQ DOMAINS (IRQ NUMBER MAPPING LIBRARY)
diff --git a/arch/arm/mach-mvebu/armada-370-xp.h b/arch/arm/mach-mvebu/armada-370-xp.h
index 237c86b83390..c3465f5b1250 100644
--- a/arch/arm/mach-mvebu/armada-370-xp.h
+++ b/arch/arm/mach-mvebu/armada-370-xp.h
@@ -20,8 +20,6 @@
#define ARMADA_XP_MAX_CPUS 4
-void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq);
-void armada_xp_mpic_smp_cpu_init(void);
void armada_xp_secondary_startup(void);
extern struct smp_operations armada_xp_smp_ops;
#endif
diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c
index a6da03f5b24e..e43727f391f7 100644
--- a/arch/arm/mach-mvebu/platsmp.c
+++ b/arch/arm/mach-mvebu/platsmp.c
@@ -70,11 +70,6 @@ static void __init set_secondary_cpus_clock(void)
}
}
-static void armada_xp_secondary_init(unsigned int cpu)
-{
- armada_xp_mpic_smp_cpu_init();
-}
-
static int armada_xp_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
pr_info("Booting CPU %d\n", cpu);
@@ -90,8 +85,6 @@ static void __init armada_xp_smp_init_cpus(void)
if (ncores == 0 || ncores > ARMADA_XP_MAX_CPUS)
panic("Invalid number of CPUs in DT\n");
-
- set_smp_cross_call(armada_mpic_send_doorbell);
}
static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
@@ -124,7 +117,6 @@ static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
struct smp_operations armada_xp_smp_ops __initdata = {
.smp_init_cpus = armada_xp_smp_init_cpus,
.smp_prepare_cpus = armada_xp_smp_prepare_cpus,
- .smp_secondary_init = armada_xp_secondary_init,
.smp_boot_secondary = armada_xp_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = armada_xp_cpu_die,
diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
index 3899ba7821c5..c887e6eebc41 100644
--- a/drivers/irqchip/irq-armada-370-xp.c
+++ b/drivers/irqchip/irq-armada-370-xp.c
@@ -19,6 +19,7 @@
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/irqchip/chained_irq.h>
+#include <linux/cpu.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -310,7 +311,8 @@ static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
}
#ifdef CONFIG_SMP
-void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq)
+static void armada_mpic_send_doorbell(const struct cpumask *mask,
+ unsigned int irq)
{
int cpu;
unsigned long map = 0;
@@ -330,7 +332,7 @@ void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq)
ARMADA_370_XP_SW_TRIG_INT_OFFS);
}
-void armada_xp_mpic_smp_cpu_init(void)
+static void armada_xp_mpic_smp_cpu_init(void)
{
/* Clear pending IPIs */
writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
@@ -342,6 +344,20 @@ void armada_xp_mpic_smp_cpu_init(void)
/* Unmask IPI interrupt */
writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}
+
+static int armada_xp_mpic_secondary_init(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
+ armada_xp_mpic_smp_cpu_init();
+ return NOTIFY_OK;
+}
+
+static struct notifier_block armada_370_xp_mpic_cpu_notifier = {
+ .notifier_call = armada_xp_mpic_secondary_init,
+ .priority = 100,
+};
+
#endif /* CONFIG_SMP */
static struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
@@ -497,6 +513,10 @@ static int __init armada_370_xp_mpic_of_init(struct device_node *node,
if (parent_irq <= 0) {
irq_set_default_host(armada_370_xp_mpic_domain);
set_handle_irq(armada_370_xp_handle_irq);
+#ifdef CONFIG_SMP
+ set_smp_cross_call(armada_mpic_send_doorbell);
+ register_cpu_notifier(&armada_370_xp_mpic_cpu_notifier);
+#endif
} else {
irq_set_chained_handler(parent_irq,
armada_370_xp_mpic_handle_cascade_irq);
diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c
index e25f246cd2fb..34d18b48bb78 100644
--- a/drivers/irqchip/irq-orion.c
+++ b/drivers/irqchip/irq-orion.c
@@ -42,7 +42,7 @@ __exception_irq_entry orion_handle_irq(struct pt_regs *regs)
u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) &
gc->mask_cache;
while (stat) {
- u32 hwirq = ffs(stat) - 1;
+ u32 hwirq = __fls(stat);
u32 irq = irq_find_mapping(orion_irq_domain,
gc->irq_base + hwirq);
handle_IRQ(irq, regs);
@@ -117,7 +117,7 @@ static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
gc->mask_cache;
while (stat) {
- u32 hwirq = ffs(stat) - 1;
+ u32 hwirq = __fls(stat);
generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
stat &= ~(1 << hwirq);
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 97ac926c78a7..051c85032f48 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -272,6 +272,11 @@ static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
return -EINVAL;
}
+static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+ return 0;
+}
+
static inline int irq_can_set_affinity(unsigned int irq)
{
return 0;
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 26e2661d3935..472c021a2d4f 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -27,6 +27,8 @@ struct irq_desc;
* @irq_count: stats field to detect stalled irqs
* @last_unhandled: aging timer for unhandled count
* @irqs_unhandled: stats field for spurious unhandled interrupts
+ * @threads_handled: stats field for deferred spurious detection of threaded handlers
+ * @threads_handled_last: comparator field for deferred spurious detection of theraded handlers
* @lock: locking for SMP
* @affinity_hint: hint to user space for preferred irq affinity
* @affinity_notify: context for notification of affinity changes
@@ -52,6 +54,8 @@ struct irq_desc {
unsigned int irq_count; /* For detecting broken IRQs */
unsigned long last_unhandled; /* Aging timer for unhandled count */
unsigned int irqs_unhandled;
+ atomic_t threads_handled;
+ int threads_handled_last;
raw_spinlock_t lock;
struct cpumask *percpu_enabled;
#ifdef CONFIG_SMP
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