zephyr

History

Keith Packard 0b90fd5adf samples, tests, boards: Switch main return type from void to int As both C and C++ standards require applications running under an OS to return 'int', adapt that for Zephyr to align with those standard. This also eliminates errors when building with clang when not using -ffreestanding, and reduces the need for compiler flags to silence warnings for both clang and gcc. Most of these changes were automated using coccinelle with the following script: @@ @@ - void + int main(...) { ... - return; + return 0; ... } Approximately 40 files had to be edited by hand as coccinelle was unable to fix them. Signed-off-by: Keith Packard <keithp@keithp.com>		2023-04-14 07:49:41 +09:00
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src	samples, tests, boards: Switch main return type from void to int	2023-04-14 07:49:41 +09:00
CMakeLists.txt
prj.conf
README.rst
testcase.yaml

README.rst

Scheduler Microbenchmark
########################

This is a scheduler microbenchmark, designed to measure minimum
latencies (not scaling performance) of specific low level scheduling
primitives independent of overhead from application or API
abstractions.  It works very simply: a main thread creates a "partner"
thread at a higher priority, the partner then sleeps using
_pend_curr_irqlock().  From this initial state:

1. The main thread calls _unpend_first_thread()
2. The main thread calls _ready_thread()
3. The main thread calls k_yield()
   (the kernel switches to the partner thread)
4. The partner thread then runs and calls _pend_curr_irqlock() again
   (the kernel switches to the main thread)
5. The main thread returns from k_yield()

It then iterates this many times, reporting timestamp latencies
between each numbered step and for the whole cycle, and a running
average for all cycles run.