diff --git a/lib/Makefile b/lib/Makefile
index 648b2c1..f827e3c 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -7,6 +7,8 @@
 	 idr.o div64.o int_sqrt.o bitmap.o extable.o prio_tree.o \
 	 sha1.o
 
+lib-$(CONFIG_SMP) += cpumask.o
+
 lib-y	+= kobject.o kref.o kobject_uevent.o klist.o
 
 obj-y += sort.o parser.o halfmd4.o iomap_copy.o
diff --git a/lib/cpumask.c b/lib/cpumask.c
new file mode 100644
index 0000000..1560d97
--- /dev/null
+++ b/lib/cpumask.c
@@ -0,0 +1,11 @@
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/cpumask.h>
+#include <linux/module.h>
+
+int __first_cpu(const cpumask_t *srcp)
+{
+	return min_t(int, NR_CPUS, find_first_bit(srcp->bits, NR_CPUS));
+}
+EXPORT_SYMBOL(__first_cpu);
+