FIRST DAY
Linux kernel programming
- Development in the Linux kernel
- Memory allocation
- Linked lists
| Exercise: |
Writing the "hello world" kernel module |
| Exercise: |
Adding a driver to kernel sources and configuration menu |
| Exercise: |
Using module parameters |
| Exercise: |
Writing interdependent modules using memory allocations, reference counting and linked lists |
Linux kernel debugging
- The /proc and debugfs filesystems
- Traces
- The kernel Dynamic Debugging interface
- The Kernel Address Sanitizer
- Debugging memory problems with kmemleak
- Using the Undefined Behavior Sanitizer
- Code coverage using gcov
- Debugging with kgdb
- Debugging with a JTAG probe
| Exercise: |
Display dynamic traces on the running kernel |
| Exercise: |
Debug a module initialization using kgdb |
Kernel multi-tasking
- Task handling
- Concurrent programming
- Timers
- Kernel threads
| Exercise: |
Fixing race conditions in the previous lab with mutexes |
SECOND DAY
Introduction to Linux drivers
- Accessing the device driver from user space
- Driver registration
| Exercise: |
Step by step implementation of a character driver: |
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driver registration (major/minor reservation) and device special file creation (/dev) |
Driver I/O functions
- Kernel structures used by drivers
- Opening and closing devices
- Data transfers
- Controlling the device
- Mapping device memory
| Exercise: |
Step by step implementation of a character driver: |
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Implementing open and release |
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Implementing read and write |
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Implementing ioctl |
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Implementing mmap |
THIRD DAY
Synchronous and asynchronous requests
- Task synchronization
- Synchronous request
- Asynchronous requests
| Exercise: |
implementation of a pipe-like driver: |
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implementing waiting and waking |
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adding non-blocking, asynchronous and multiplexed operations (O_NONBLOCK, SIGIO, poll/select) |
Input/Output and interrupts
- Memory-mapped registers
- Interrupts
- Gpios
- User-level access through /sys or the GPIO character driver
| Exercise: |
Polling gpio driver with raw register access |
| Exercise: |
Interrupt-based gpio driver with raw register access |
| Exercise: |
gpio driver using the gpiolib |
Busses
- Plug-and-Play management
- Static devices declaration
- in the BSP code
- in the device tree
- Platform bus
- PCI
- SPI
- Power management
- System sleep
- Implementing power management in drivers
- Remote wakeup
| Exercise: |
Implementing a platform driver and customizing the device tree to associate it to its device (a serial port) |
| Exercise: |
Implementing power management in the previous driver |
| Exercise: |
Implementing remote wakeup in the previous driver |
FOURTH DAY
Linux Driver Model
- Linux Driver Model Architecture
- Hot plug management
- Plugging devices
- Removing devices
- Writing udev rules
| Exercise: |
Writing a custom class driver |
| Exercise: |
Writing a misc driver |
DMA
- Direct Memory Access
- DMA scenarios
- Buffer access
- DMA programming
- Memory barriers
| Exercise: |
Implementing slave DMA in a serial port driver |
ANNEXES
USB Drivers
- The USB bus
- USB devices
- User-space USB interface
- USB descriptors
- USB requests
- USB device drivers
| Exercise: |
Writing a USB host driver |
Network drivers
- structures
- network interface representation (struct net_device)
- network packet (struct sk_buff)
- scatter/gather
- interface
- receiving packets
- sending packets
- lost packets management
- network interface statistics
- New network API (NAPI)
- "interrupt mitigation" (suppression of unneeded IRQs)
- "packet throttling" (suppression of packets in the driver itself when system is overwhelmed)
Memory management
- Virtual Memory
- Memory Allocation
- Free page management
- Normal memory allocation
- Virtual memory allocation
- Huge allocations
registration form
