On 3/21/19 11:20 PM, Rafael J. Wysocki wrote:
From: Rafael J. Wysocki <[email protected]>
The Performance and Energy Bias Hint (EPB) is expected to be set by
user space through the generic MSR interface, but that interface is
not particularly nice and there are security concerns regarding it,
so it is not always available.
For this reason, add a sysfs interface for reading and updating the
EPB, in the form of a new attribute, energy_perf_bias, located
under /sys/devices/system/cpu/cpu#/power/ for online CPUs that
support the EPB feature.
Signed-off-by: Rafael J. Wysocki <[email protected]>
---
Documentation/ABI/testing/sysfs-devices-system-cpu | 18 ++++
Documentation/admin-guide/pm/intel_epb.rst | 27 ++++++
arch/x86/kernel/cpu/intel_epb.c | 93
++++++++++++++++++++-
3 files changed, 134 insertions(+), 4 deletions(-)
Reviewed-by: Hannes Reinecke <[email protected]>
Cheers,
Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
[email protected] +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
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