Linux driver example to print the current running CPU - smp_processor_id()

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When you have multiple processors present in the system, and want to find out on which the processor your driver code is running, use smp_processor_id().

Header file: #include <linux/smp.h>

Example:


Output:

You can see from the above screenshot, the init function of the driver was running on Processor 1 and Kernel thread was running on Processor 4

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