unbound: testcode/checklocks.h File Reference

unbound 0.1

checklocks.h File Reference

testcode/checklocks.h - wrapper on locks that checks access. More...

## Detailed Description

testcode/checklocks.h - wrapper on locks that checks access.

Copyright (c) 2007, NLnet Labs. All rights reserved.

This software is open source.

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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.