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);
+