Part 3: Kernel Essentials
This section covers Zephyr’s kernel fundamentals - threads, scheduling, interrupts, timing, and kernel objects.
What You’ll Learn
- Creating and managing threads
- Understanding the scheduler and priorities
- Implementing interrupt handlers (ISRs)
- Using timing services (delays, timers)
- Working with workqueues
- Choosing the right kernel objects
- Memory management strategies for embedded systems
Chapters
| Chapter | Description |
|---|---|
| Threads | Thread creation, lifecycle, and attributes |
| Scheduling | Scheduler, priorities, and preemption |
| Interrupts | ISR implementation and restrictions |
| Timing | Kernel ticks, delays, sleep, timers |
| Workqueues | System workqueue and k_work |
| Kernel Objects | Object taxonomy and selection |
| Memory Management | Heaps, slabs, memory blocks, and allocation strategies |
Kernel Architecture Overview
flowchart TB
subgraph Threads["Thread Management"]
T1[Thread 1]
T2[Thread 2]
T3[Thread 3]
end
subgraph Scheduler["Scheduler"]
READY[Ready Queue]
RUNNING[Running Thread]
PEND[Pending Threads]
end
subgraph Services["Kernel Services"]
TIMING[Timing]
SYNC[Synchronization]
IPC[IPC]
end
Threads --> Scheduler
Scheduler --> Services
Prerequisites
Before starting this section, you should have:
- Completed Parts 1-2 (working build environment)
- Understanding of C programming
- Basic knowledge of concurrent programming concepts
The kernel is the heart of Zephyr. Understanding these concepts is essential for writing reliable embedded applications.