On Thu, Mar 03, 2005 at 04:29:03PM -0800, Om wrote: > In an smp environment, what prevents 2 different cpu's from aquiring > same spin lock at exactly the same time? I was expecting `lock` to be > atomic, and the inc and dec operations were also atomic operations. You're looking at the wrong definition of _raw_spin_lock(). For x86, look at include/asm-i386/spinlock.h, where you can find it uses spin_lock_string, which uses a "lock" prefix to atomically increment or decrement the lock. Erik -- Erik Mouw J.A.K.Mouw@xxxxxxxxxxxxxx mouw@xxxxxxxxxxxx
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