On Tue, 24 Jul 2007, Trond Myklebust wrote: > > That's not what the Documentation/memory-barriers.txt states: Hmm.. You're right. We only actually need it for the unconditional bitops, like the *unlock* side. IOW, if you do a spinlock with the bitops, the locking side should be able to use a "test_and_set_bit()" on its own, but the unlocking side should be smp_mb__before_clear_bit(); clear_bit(); because the ones that don't return a value also don't imply a memory barrier. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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