News: 0001509576

  ARM Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life (Terry Pratchett, Jingo)

AMD Per-Core Energy Counter Support Slated For Linux 6.14

([AMD] 2 Hours Ago Per-Core Energy Monitoring)


While the [1]Linux 6.13 merge window just closed yesterday in landing all of the new features and functionality for that first kernel version of 2025, already for the Linux 6.14 kernel cycle to follow a feature was queued up early this morning in a TIP branch: AMD per-core energy counter support.

The past few months AMD Linux engineers have been working on per-core energy counter support under the Linux Runtime Average Power Limiting (RAPL) infrastructure. After going through [2]the v7 patches , they are now ready for the mainline Linux kernel once Linux 6.14 rolls around with its merge window in late January / early February.

The AMD per-core energy counter patch series explains:

"Currently the energy-cores event in the power PMU aggregates energy consumption data at a package level. On the other hand the core energy RAPL counter in AMD CPUs has a core scope (which means the energy consumption is recorded separately for each core). Earlier efforts to add the core event in the power PMU had failed [1], due to the difference in the scope of these two events. Hence, there is a need for a new core scope PMU.

This patchset adds a new "power_core" PMU alongside the existing "power" PMU, which will be responsible for collecting the new "energy-core" event.

Tested the package level and core level PMU counters with workloads pinned to different CPUs."

As of this morning, the patches were picked up by the [3]tip/tip.git's perf/core branch .

With the patches now queued as part of the TIP branch and with two months to go until the Linux 6.14 cycle, it looks like the per-core energy counter support is ready to roll with that next kernel cycle. Linux 6.14 is also going to be exciting for AMD customers with [4]the AMDXDNA driver ready for inclusion in supporting the Ryzen AI NPU on the mainline Linux kernel.



[1] https://www.phoronix.com/news/Linux-6.13-rc1-Released

[2] https://lore.kernel.org/all/20241115060805.447565-1-Dhananjay.Ugwekar@amd.com/

[3] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=perf/core

[4] https://www.phoronix.com/news/AMDXDNA-DRM-Misc-Next



Mitch

Terence, this is stupid stuff:
You eat your victuals fast enough;
There can't be much amiss, 'tis clear,
To see the rate you drink your beer.
But oh, good Lord, the verse you make,
It gives a chap the belly-ache.
The cow, the old cow, she is dead;
It sleeps well the horned head:
We poor lads, 'tis our turn now
To hear such tunes as killed the cow.
Pretty friendship 'tis to rhyme
Your friends to death before their time.
Moping, melancholy mad:
Come, pipe a tune to dance to, lad.
-- A. E. Housman