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Context Switching
How the kernel pauses one task and resumes another: saving and restoring CPU registers to each task's own stack, on Cortex-M via PendSV, PSP/MSP, and hardware auto-stacking.
22 min read
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What exactly happens during a context switch?How does a context switch work on a Cortex-M specifically?Why does FreeRTOS (on Cortex-M) perform the switch in PendSV rather than directly in SysTick?What's the cost of a context switch and why does it matter?How does the FPU affect context switching on a Cortex-M, and how is it handled?
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