--- linux-2.6.32/arch/mips/oprofile/op_model_mipsxx.c.orig	2011-01-21 16:59:20.000000000 +0100
+++ linux-2.6.32/arch/mips/oprofile/op_model_mipsxx.c	2011-05-09 11:39:57.295250869 +0200
@@ -298,6 +298,11 @@
 	}
 }
 
+static irqreturn_t mipsxx_perfcount_int(int irq, void *dev_id)
+{
+	return mipsxx_perfcount_handler();
+}
+
 static int __init mipsxx_init(void)
 {
 	int counters;
@@ -383,6 +388,10 @@
 	save_perf_irq = perf_irq;
 	perf_irq = mipsxx_perfcount_handler;
 
+	if (cp0_perfcount_irq >= 0)
+		return request_irq(cp0_perfcount_irq, mipsxx_perfcount_int,
+			IRQF_SHARED, "Perfcounter", save_perf_irq);
+
 	return 0;
 }
 
@@ -390,6 +399,9 @@
 {
 	int counters = op_model_mipsxx_ops.num_counters;
 
+	if (cp0_perfcount_irq >= 0)
+		free_irq(cp0_perfcount_irq, save_perf_irq);
+
 	counters = counters_per_cpu_to_total(counters);
 	on_each_cpu(reset_counters, (void *)(long)counters, 1);