Documentation/ABI/testing/sysfs-bus-event_source-devices-caps

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-bus-event_source-devices-caps

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-bus-event_source-devices-caps
Extension
[no extension]
Size
1043 bytes
Lines
25
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

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

		The "branch_counter_nr" in the supported platform exposes the
		maximum number of counters which can be shown in the u64 counters
		of PERF_SAMPLE_BRANCH_COUNTERS, while the "branch_counter_width"
		exposes the width of each counter. Both of them can be used by
		the perf tool to parse the logged counters in each branch.

Annotation

Implementation Notes