Re: Preemptive linux

AFAIK, you need call preempt_check_resched() for make your syscall
preemtible for opportunity to switch context. So your code should be
like following:

int sys_foo(void)
{
while (1)
preempt_check_resched();
return 0;
}

Also you need to set TIF_NEED_RESCHED flag for this thread if it should
be rescheduled and when this thread call preempt_check_resched() in
next time it will be rescheduled.

Of course, preemption also must be enabled by preempt_enable().

.

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