docs: ABI: sysfs-bus-event_source-devices: Document sysfs caps entry for PMU

Details is added about "caps" attribute group in the ABI documentation.
This is used to expose some of the PMU attributes in "caps"
directory under : /sys/bus/event_source/devices/<dev>/. The dev/caps
will contain information about features that platform specific PMU
supports.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220520084630.15181-2-atrajeev@linux.vnet.ibm.com
This commit is contained in:
Athira Rajeev 2022-05-20 14:16:30 +05:30 коммит произвёл Michael Ellerman
Родитель 6320e693d9
Коммит 999d7c47a0
1 изменённых файлов: 18 добавлений и 0 удалений

Просмотреть файл

@ -0,0 +1,18 @@
What: /sys/bus/event_source/devices/<dev>/caps
Date: May 2022
KernelVersion: 5.19
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description:
Attribute group to describe the capabilities exposed
for a particular pmu. Each attribute of this group can
expose information specific to a PMU, say pmu_name, so that
userspace can understand some of the feature which the
platform specific PMU supports.
One of the example available capability in supported platform
like Intel is pmu_name, which exposes underlying CPU name known
to the PMU driver.
Example output in powerpc:
grep . /sys/bus/event_source/devices/cpu/caps/*
/sys/bus/event_source/devices/cpu/caps/pmu_name:POWER9