testcode/checklocks.h - wrapper on locks that checks access. More...
testcode/checklocks.h - wrapper on locks that checks access.
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Locks that are checked.
Holds information per lock and per thread. That information is protected by a mutex (unchecked).
Checks: o which func, file, line created the lock. o contention count, measures amount of contention on the lock. o the memory region(s) that the lock protects are memcmp'ed to ascertain no race conditions. o checks that locks are unlocked properly (before deletion). keeps which func, file, line that locked it. o checks deadlocks with timeout so it can print errors for them.
Limitations: o Detects unprotected memory access when the lock is locked or freed, which detects races only if they happen, and only if in protected memory areas. o Detects deadlocks by timeout, so approximately, as they happen. o Does not check order of locking. o Uses a lot of memory. o The checks use locks themselves, changing scheduling, thus changing what races you see.