Change Details

Compiler membars do not prevent the CPU from executing the code out of order. Replace them with proper barriers. This also lets us get rid of the mutex; instead, loop until the cmpset succeeds. Sponsored by: Klara, Inc.

Compiler memory barriers do not prevent the CPU from executing the code out of order. Switch to C11 atomics. This also lets us get rid of the mutex; instead, loop until the compare_exchange succeeds. While here, change the return value of at_quick_exit() on failure to the more traditional -1, matching atexit(). Sponsored by: Klara, Inc.

Compiler membarsory barriers do not prevent the CPU from executing the code out of order. Replace them with proper barriersSwitch to C11 atomics. This also lets us get rid of the us get rid of the mutex; instead, loop until the compare_exchange succeeds. While here, change the return value of at_quick_exit() on failure to the more traditional -1, loop until the cmpset succeedsmatching atexit(). Sponsored by: Klara, Inc.