Fastest inline-assembly spinlock

Question

I\'m writing a multithreaded application in c++, where performance is critical. I need to use a lot of locking while copying small structures between threads, for this I hav

Answer 1

Although there is already an accepted answer, there are a few things that where missed that could be used to improve all the answers, taken from this Intel article, all above fast lock implementation:

1. Spin on a volatile read, not an atomic instruction, this avoids unneeded bus locking, especially on highly contended locks.
2. Use back-off for highly contested locks
3. Inline the lock, preferably with intrinsics for compilers where inline asm is detrimental (basically MSVC).