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by TickleSteve 2538 days ago
Regarding point 2)

That is not how OS level threads would work. When a lock is released, the next ready-to-run task (blocked on that lock) will be made runnable. They wont all be released then 'race' to acquire the lock. The behaviour is identical in user-space or kernel-space.
1 comments
scott_s 2538 days ago
That depends on the synchronization mechanism used, and whether or not that mechanism is hooked into the kernel scheduler. Sometimes it is (such as pthread_mutex) and sometimes it is not (such as rolling your own spin locks).
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TickleSteve 2538 days ago
ok, any "sane" implementation would not use spin-locks for this purpose, but yes it is technically possible to do so.

Spin-locks are not really the mechanism of choice for this level of abstraction.

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