Here is a first cut at multicore support for coremark on pico.
https://github.com/manitou48/CoreMark-RP2040
For single core (in RAM, UART and no USB) i get 249.807440 iterations/sec. For 2 cores, I get 482.000688 iterations/sec, a speedup of 1.9. you need multicore_launch_core1_with_stack() and I just guessed at 2nd stack location/size. I'm not sure of relation of default_num_contexts and MULTITHREAD, i had to alter code in core_main.c.
Here is a first cut at multicore support for coremark on pico.
https://github.com/manitou48/CoreMark-RP2040
For single core (in RAM, UART and no USB) i get 249.807440 iterations/sec. For 2 cores, I get 482.000688 iterations/sec, a speedup of 1.9. you need multicore_launch_core1_with_stack() and I just guessed at 2nd stack location/size. I'm not sure of relation of default_num_contexts and MULTITHREAD, i had to alter code in core_main.c.