Messages in this thread | | | From | "David Schwartz" <> | Subject | RE: Uses for memory barriers | Date | Thu, 7 Sep 2006 22:52:32 -0700 |
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> Am I correct? Or are there some easily-explained situations where mb() > really should be used for inter-CPU synchronization?
Consider when one CPU does the following:
while(!spinlock_acquire()) relax(); x=shared_value_protected_by_spinlock;
We need to make sure we do not *read* the protected values (say due to prefetching) before other CPUs see our write that locks the spinlock.
DS
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