The Linux kernel is one of the most mysterious of open source projects. A lot of documentation exists, however it is still a difficult subject to comprehend. The Interactive Linux kernel map’s intent is to help people gain an overview of the structure and interactions of the Linux Kernel. Its approach is similar to classic operating system diagrams in that application and user space interfaces are on the top, hardware interfaces and drivers are on the bottom and separate functions are shown in vertical bars. This map is not just a static diagram, it is interactive.
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You can zoom into and drag around to see details. More than 250 most important files, structures and functions are spread over the map. Each function or other object has a hypertext link to its full Linux source. For example, you may find a module that interests you, click on its key function and then examine its source code and continue surfing to the Linux cross reference site. Furthermore, all functions are connected. You may trace call stack and data flow from a system call to hardware or from a interrupt back to a system call.