On Fri, Feb 21, 2025 at 04:54:40PM +0000, Chris MacNamara wrote: > 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]>
Minor nit, this is kept in alphabetical order, so your name should go just above Chris Wright's one. > 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()`` > -- I'd suggest this extra info be added as a note, rather than inline in the text, since it's not applicable to all systems. I'd also suggest that an equivalent note needs to be added to the programmer's guide doc, in [1]. The info is relevant for those using the library, as well as those just using the sample app. /Bruce [1] https://doc.dpdk.org/guides/prog_guide/power_man.html#ethernet-pmd-power-management-api
