On Thu, Nov 20, 2025 at 8:39 PM Xiang Xiao <[email protected]> wrote:
> Basically, signal has two reaction: > > 1. Call the signal handler function in the target process/task > 2. Wake up the target thread just like sem post > > The major memory/code size contribution comes from the first item, the > second item consumes the small code/memory, but could keep many frequently > used functions(e.g. sleep/usleep/wait etc.). So, I would suggest that the > signal is disabled by level to make it more useful in different cases: > > 1. Disable all signal related functionality( > https://github.com/apache/nuttx/pull/17352) > 2. Disable signal handler(callback), but keep signal wakeup > functionality > (https://github.com/apache/nuttx/pull/17357) > 3. Enable all signal functionality like before For the case of waking up a thread, any current use of signals would have to be replaced with a different IPC, as sem_post() that you suggest. There a also lot of hidden uses of signals in the OS for notifications and things like device driver timeouts. Those uses would not be simple to replace.
