5 files changed, 33 insertions, 7 deletions

diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 4571ae7e085a..99c3bc8a6fb4 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -3,6 +3,12 @@
  */
 #include <linux/irqdesc.h>
 
+#ifdef CONFIG_SPARSE_IRQ
+# define IRQ_BITMAP_BITS        (NR_IRQS + 8196)
+#else
+# define IRQ_BITMAP_BITS        NR_IRQS
+#endif
+
 extern int noirqdebug;
 
 #define irq_data_to_desc(data)  container_of(data, struct irq_desc, irq_data)
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 282f20230e67..2039bea31bdf 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -94,7 +94,7 @@ int nr_irqs = NR_IRQS;
 EXPORT_SYMBOL_GPL(nr_irqs);
 
 static DEFINE_MUTEX(sparse_irq_lock);
-static DECLARE_BITMAP(allocated_irqs, NR_IRQS);
+static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
 
 #ifdef CONFIG_SPARSE_IRQ
 
@@ -217,6 +217,15 @@ int __init early_irq_init(void)
         initcnt = arch_probe_nr_irqs();
         printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
 
+        if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
+                nr_irqs = IRQ_BITMAP_BITS;
+
+        if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
+                initcnt = IRQ_BITMAP_BITS;
+
+        if (initcnt > nr_irqs)
+                nr_irqs = initcnt;
+
         for (i = 0; i < initcnt; i++) {
                 desc = alloc_desc(i, node);
                 set_bit(i, allocated_irqs);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0caa59f747dd..9033c1c70828 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1100,7 +1100,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
         if (retval)
                 kfree(action);
 
-#ifdef CONFIG_DEBUG_SHIRQ
+#ifdef CONFIG_DEBUG_SHIRQ_FIXME
         if (!retval && (irqflags & IRQF_SHARED)) {
                 /*
                  * It's a shared IRQ -- the driver ought to be prepared for it
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 891115a929aa..dc49358b73fa 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -23,7 +23,7 @@
 #ifdef CONFIG_HARDIRQS_SW_RESEND
 
 /* Bitmap to handle software resend of interrupts: */
-static DECLARE_BITMAP(irqs_resend, NR_IRQS);
+static DECLARE_BITMAP(irqs_resend, IRQ_BITMAP_BITS);
 
 /*
  * Run software resends of IRQ's
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 999835b6112b..656222fcf767 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -782,6 +782,10 @@ retry:
         raw_spin_unlock_irq(&ctx->lock);
 }
 
+#define MAX_INTERRUPTS (~0ULL)
+
+static void perf_log_throttle(struct perf_event *event, int enable);
+
 static int
 event_sched_in(struct perf_event *event,
                  struct perf_cpu_context *cpuctx,
@@ -794,6 +798,17 @@ event_sched_in(struct perf_event *event,
 
         event->state = PERF_EVENT_STATE_ACTIVE;
         event->oncpu = smp_processor_id();
+
+        /*
+         * Unthrottle events, since we scheduled we might have missed several
+         * ticks already, also for a heavily scheduling task there is little
+         * guarantee it'll get a tick in a timely manner.
+         */
+        if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) {
+                perf_log_throttle(event, 1);
+                event->hw.interrupts = 0;
+        }
+
         /*
          * The new state must be visible before we turn it on in the hardware:
          */
@@ -1596,10 +1611,6 @@ void __perf_event_task_sched_in(struct task_struct *task)
         }
 }
 
-#define MAX_INTERRUPTS (~0ULL)
-
-static void perf_log_throttle(struct perf_event *event, int enable);
-
 static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
 {
         u64 frequency = event->attr.sample_freq;