The move to arch_switch() is a prerequisite for SMP support.
Make it optimal without the need for an ECALL roundtrip on every
context switch. Performance numbers from tests/benchmarks/sched:
Before:
unpend 107 ready 102 switch 188 pend 218 tot 615 (avg 615)
After:
unpend 107 ready 102 switch 170 pend 217 tot 596 (avg 595)
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Added test which estimates stack usage of few types of logging
messages in various modes, with and without optimization. Test
was used to determine usage for various architectures and is expected
to be used to detect stack usage increase since it fails when
stack usage in given configuration goes beyond the hardcoded limit.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
