- int spins=100000;
- /* Do not use futexes because we insist that unlocking is a simple
- * assignment to optimize non-pathological code with no contention. */
- while (a_xchg(l, 1))
- if (spins) spins--, a_spin();
- else __syscall(SYS_sched_yield);
+ while (a_swap(l, 1)) __wait(l, l+1, 1, 1);
+}
+
+void __unlock(volatile int *l)
+{
+ a_store(l, 0);
+ if (l[1]) __wake(l, 1, 1);