After downloading the Linux kernel source package and extract every meaning of the root directory of the Linux kernel source tree do not quite understand, like the study estimated that each kernel source code, there will be a small partner started this question, therefore, where the Linux kernel each source file in the root directory of the package do profiles, so like a small kernel source research partners have a general understanding of the core of this looks particularly mysterious and complicated things.
Specific details, please see table below:
| table of Contents | Meaning Description |
| arch | Source specific architecture |
| block | Block device I / O layer |
| crypto | Crypto API |
| Documentation | Kernel source documentation |
| drivers | Device Drivers |
| firmware | Some drivers need a device firmware |
| fs | VFS and various file systems |
| include | Kernel headers |
| init | And kernel boot initialization |
| ipc | Interprocess communication codes |
| kernel | The core scheduler subsystem |
| lib | Generic kernel function |
| LICENSES | Kernel-related files lincese |
| mm | Memory management subsystem and VM |
| net | Network Subsystem |
| samples | Sample, sample code |
| scripts | Script used to compile the kernel |
| security | Linux kernel security module |
| sound | Voice subsystem |
| tools | Useful in Linux development tools |
| usr | Early user space code |
| virt | Virtualization Infrastructure |
Download the kernel source: https://www.kernel.org/