doc: add cycles per packet in testpmd guide

Update documentation for 'show fwd' testpmd runtime function to show
CPU cycles/packet example.

Signed-off-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
index 3ded179..a808b6a 100644 (file)
--- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
+++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
@@ -372,6 +372,12 @@ Example for the io forwarding engine, with some packet drops on the tx side::
      TX-packets: 548595568      TX-dropped: 128           TX-total: 548595696
      ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
+.. note::
+
+   Enabling CONFIG_RTE_TEST_PMD_RECORD_CORE_CYCLES appends "CPU cycles/packet" stats, like:
+
+   CPU cycles/packet=xx.dd (total cycles=xxxx / total RX packets=xxxx) at xxx MHz clock
+
 clear fwd
 ~~~~~~~~~