Messages in this thread | | | Date | Thu, 21 Sep 2017 14:45:31 +0200 | From | Peter Zijlstra <> | Subject | Re: Memory-ordering recipes |
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On Sun, Sep 17, 2017 at 04:05:09PM -0700, Paul E. McKenney wrote:
> So what litmus tests are needed? Here is my initial set: > > 1. Release-acquire chains, AKA ISA2, Z6.2, LB, and 3.LB > > Lots of variety here, can in some cases substitute: > > a. READ_ONCE() for smp_load_acquire() > b. WRITE_ONCE() for smp_store_release() > c. Dependencies for both smp_load_acquire() and > smp_store_release(). > d. smp_wmb() for smp_store_release() in first thread > of ISA2 and Z6.2. > e. smp_rmb() for smp_load_acquire() in last thread of ISA2. > > 2. MP (see test6.pdf for nickname translation) > > a. smp_store_release() / smp_load_acquire() > b. rcu_assign_pointer() / rcu_dereference() > c. smp_wmb() / smp_rmb() > d. Replacing either of the above with smp_mb() > > 3. SB > > a. smp_mb(), as in lockless wait-wakeup coordination. > And as in sys_membarrier()-scheduler coordination, > for that matter. > > Others?
So I have no idea what you're proposing here. The above is just a bunch of words without meaning :-(
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