On Wed, 2012-05-02 at 13:25 -0700, Hugh Dickins wrote: > Got it at last. Embarrassingly obvious. __rcu_read_lock() and > __rcu_read_unlock() are not safe to be using __this_cpu operations, > the cpu may change in between the rmw's read and write: they should > be using this_cpu operations (or, I put preempt_disable/enable in the > __rcu_read_unlock below). __this_cpus there work out fine on x86, > which was given good instructions to use; but not so well on PowerPC. > > I've been running successfully for an hour now with the patch below; > but I expect you'll want to consider the tradeoffs, and may choose a > different solution.
Didn't Linus recently rant about these __this_cpu vs this_cpu nonsense ? I thought that was going out.. Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
