kset

kset is a kernel data structure used in the Linux kernel as part of the kobject and sysfs subsystems. It represents a collection of kernel objects (kobjects) that share a common purpose, interface, or owner. A kset groups related kobjects so that subsystem code can manage them collectively and expose their attributes in sysfs.

A kset is associated with a specific owner, usually a kernel module, which provides the module's reference for lifetime management and symbol resolution. The kset mechanism allows subsystem developers to register a set of kobjects and their attributes without needing to manage each object individually at higher levels of the subsystem.

In practice, subsystem code creates a kset and then creates and registers kobjects within that set. Attributes and operations defined for the set standardize how objects in the set are created, iterated, or removed, and how events are propagated to userspace (for example, via sysfs uevents). This organization helps the kernel maintain a coherent sysfs hierarchy corresponding to a given subsystem, such as devices, drivers, or other kernel components.

Ksets are an internal implementation detail of the kobject/sysfs model. They provide lifecycle management, ownership, and a grouping mechanism that enables modular, scalable kernel object management. The concept is primarily of interest to kernel developers, device drivers, and subsystems that rely on sysfs-based representations.

See also: kobject, sysfs, kset_ops, kernel object lifetime management.