1 files changed, 17 insertions, 0 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c
index ba2f8543052c..ea25a034276c 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -14,3 +14,20 @@ int __next_cpu(int n, const cpumask_t *srcp)
 	return min_t(int, NR_CPUS, find_next_bit(srcp->bits, NR_CPUS, n+1));
 }
 EXPORT_SYMBOL(__next_cpu);
+
+/*
+ * Find the highest possible smp_processor_id()
+ *
+ * Note: if we're prepared to assume that cpu_possible_map never changes
+ * (reasonable) then this function should cache its return value.
+ */
+int highest_possible_processor_id(void)
+{
+	unsigned int cpu;
+	unsigned highest = 0;
+
+	for_each_cpu_mask(cpu, cpu_possible_map)
+		highest = cpu;
+	return highest;
+}
+EXPORT_SYMBOL(highest_possible_processor_id);