docs: document the sysfs ABI for "nohz_full"

Add missing documentation of sysfs ABI for "nohz_full". It was added
by commit 6570a9a1ce3a("show nohz_full cpus in sysfs"). However,
there is no documentation for these interface.

Signed-off-by: Kohei Tarumizu <tarumizu.kohei@fujitsu.com>
Link: https://lore.kernel.org/r/20211201115957.254224-2-tarumizu.kohei@fujitsu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 69c65da..f84c32f 100644 (file)
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -666,3 +666,10 @@ Description:       Preferred MTE tag checking mode
                ================  ==============================================
 
                See also: Documentation/arm64/memory-tagging-extension.rst
+
+What:          /sys/devices/system/cpu/nohz_full
+Date:          Apr 2015
+Contact:       Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:
+               (RO) the list of CPUs that are in nohz_full mode.
+               These CPUs are set by boot parameter "nohz_full=".