On Thu, 2015-06-04 at 12:31 +0200, Jesper Dangaard Brouer wrote: > This patch improves performance of SLUB allocator fastpath with 38% by > avoiding the call to this_cpu_cmpxchg_double() for NO-PREEMPT kernels. > > Reviewers please point out why this change is wrong, as such a large > improvement should not be possible ;-)
I am not sure if anyone already answered, but the cmpxchg_double() is needed to avoid the ABA problem. This is the whole point using tid _and_ freelist Preemption is not the only thing that could happen here, think of interrupts. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
