swap
WHAT
DEF
1. is HW synchronization primitive
HW primitive for synchronization
HOW
HW like..
void Swap(boolean &a, boolean &b) {
boolean temp = a;
a = b;
b = temp;
}how to provide Mutual Exclusion?
boolean lock = false;
do {
key = true;
while (key == true) Swap(lock, key);
CRITICAL_SECTION;
lock = false;
REMAINDER_SECTION;
}