percpu: add test module for various percpu operations

Tests various percpu operations.

Enable with CONFIG_PERCPU_TEST=m.

Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index ebef88f..db25707 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1481,6 +1481,15 @@
 	help
 	  A benchmark measuring the performance of the interval tree library
 
+config PERCPU_TEST
+	tristate "Per cpu operations test"
+	depends on m && DEBUG_KERNEL
+	help
+	  Enable this option to build test module which validates per-cpu
+	  operations.
+
+	  If unsure, say N.
+
 config ATOMIC64_SELFTEST
 	bool "Perform an atomic64_t self-test at boot"
 	help