Documentation/ABI/testing/sysfs-devices-system-cpu

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-devices-system-cpu

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-devices-system-cpu
Extension
[no extension]
Size
30959 bytes
Lines
809
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/devices/system/cpu/
Date:		pre-git history
Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description:
		A collection of both global and individual CPU attributes

		Individual CPU attributes are contained in subdirectories
		named by the kernel's logical CPU number, e.g.:

		/sys/devices/system/cpu/cpuX/

What:		/sys/devices/system/cpu/kernel_max
		/sys/devices/system/cpu/offline
		/sys/devices/system/cpu/online
		/sys/devices/system/cpu/possible
		/sys/devices/system/cpu/present
Date:		December 2008
Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description:	CPU topology files that describe kernel limits related to
		hotplug. Briefly:

		kernel_max: the maximum cpu index allowed by the kernel
		configuration.

		offline: cpus that are not online because they have been
		HOTPLUGGED off or exceed the limit of cpus allowed by the
		kernel configuration (kernel_max above).

		online: cpus that are online and being scheduled.

		possible: cpus that have been allocated resources and can be
		brought online if they are present.

		present: cpus that have been identified as being present in
		the system.

		See Documentation/admin-guide/cputopology.rst for more information.


What:		/sys/devices/system/cpu/probe
		/sys/devices/system/cpu/release
Date:		November 2009
Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description:	Dynamic addition and removal of CPU's.  This is not hotplug
		removal, this is meant complete removal/addition of the CPU
		from the system.

		probe: writes to this file will dynamically add a CPU to the
		system.  Information written to the file to add CPU's is
		architecture specific.

		release: writes to this file dynamically remove a CPU from
		the system.  Information written to the file to remove CPU's
		is architecture specific.

What:		/sys/devices/system/cpu/cpuX/node
Date:		October 2009
Contact:	Linux memory management mailing list <linux-mm@kvack.org>
Description:	Discover NUMA node a CPU belongs to

		When CONFIG_NUMA is enabled, a symbolic link that points
		to the corresponding NUMA node directory.

		For example, the following symlink is created for cpu42
		in NUMA node 2:

		/sys/devices/system/cpu/cpu42/node2 -> ../../node/node2


What:		/sys/devices/system/cpu/cpuX/topology/core_siblings

Annotation

Implementation Notes