How to multi-thread this?
- by WilliamKF
I wish to have two threads. The first thread1 occasionally calls the following pseudo function:
void waitForThread2() {
if (thread2 is not idle) {
return;
}
notifyThread2IamReady();
while (thread2IsExclusive) {
}
}
The second thread2 is forever in the following pseudo loop:
for (;;) {
Notify thread1 I am idle.
while (!thread1IsReady()) {
}
Notify thread1 I am exclusive.
Do some work while thread1 is blocked.
Notify thread1 I am busy.
Do some work in parallel with thread1.
}
What is the best way to write this such that both thread1 and thread2 are kept as busy as possible on a machine with multiple cores. I would like to avoid long delays between notification in one thread and detection by the other. I tried using pthread condition variables but found the delay between thread2 doing 'notify thread1 I am busy' and the loop in waitForThread2() on thear2IsExclusive() can be up to almost one second delay. I then tried using a volatile sig_atomic_t shared variable to control the same, but something is going wrong, so I must not be doing it correctly.
