A recent CPU change requires an extra enabling step for the umonitor instruction on Intel CPUs. This is now detailed in the l3 fwd power manager doc.
Signed-off-by: Chris MacNamara <[email protected]> --- .mailmap | 1 + doc/guides/sample_app_ug/l3_forward_power_man.rst | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/.mailmap b/.mailmap index a03d3cfb59..c4bc38752f 100644 --- a/.mailmap +++ b/.mailmap @@ -263,6 +263,7 @@ Christopher Reder <[email protected]> Christoph Gysin <[email protected]> Christos Ricudis <[email protected]> Chris Wright <[email protected]> +Chris MacNamara <[email protected]> Chuanshe Zhang <[email protected]> Chuanyu Xue <[email protected]> Chuhong Yao <[email protected]> diff --git a/doc/guides/sample_app_ug/l3_forward_power_man.rst b/doc/guides/sample_app_ug/l3_forward_power_man.rst index 3271bc2154..d0af28e0ec 100644 --- a/doc/guides/sample_app_ug/l3_forward_power_man.rst +++ b/doc/guides/sample_app_ug/l3_forward_power_man.rst @@ -293,6 +293,11 @@ and has three available power management schemes: ``monitor`` This will use ``rte_power_monitor()`` function to enter a power-optimized state (subject to platform support). + On recent Gen 4 Xeon Scalable Processors the umonitor instruction + is disabled by default. + An additional step is required to enable the umonitor instruction. + Writing 0 to bit 6 of register 0x123 will enable umonitor. + `More details are available via Monitor and Umonitor Performance Guidance <https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/monitor-umonitor-performance-guidance.html>`_ ``pause`` This will use ``rte_power_pause()`` or ``rte_pause()`` -- 2.43.0 -------------------------------------------------------------- Intel Research and Development Ireland Limited Registered in Ireland Registered Office: Collinstown Industrial Park, Leixlip, County Kildare Registered Number: 308263 This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.
