Add the description of kernel data structure(hlist_head and hlist_node or hash table)

Description

Contributor guide

Tech stack

c

Domain

documentation

Issue type

documentation

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

mostly clear

Prerequisites

C programmingLinux kernel basicsdata structures concepts

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

40

Research direction

Start by reviewing the existing documentation in the linux insides repository for similar kernel data structures, such as list head. Understand the kernel's implementation of hlist head and hlist node by looking at include/linux/types.h and include/linux/list.h. Write a clear description of the hash table (hlist) data structure, its purpose, and usage in the kernel.