void __lock(volatile int *l)
{
- if (!libc.threaded) return;
+ int need_locks = libc.need_locks;
+ if (!need_locks) return;
/* fast path: INT_MIN for the lock, +1 for the congestion */
int current = a_cas(l, 0, INT_MIN + 1);
+ if (need_locks < 0) libc.need_locks = 0;
if (!current) return;
/* A first spin loop, for medium congestion. */
for (unsigned i = 0; i < 10; ++i) {