Re: [PATCH v3 00/11] smp: cross CPU call interface

[Christoph Hellwig]

I still haven't seen any good rationale for this.  It causes massive
churn just to have more complicated interface (and thus more code)
than before.  What is the benefit?

I'm also not sure what is formal about this interface, or why it
should be formal.  IPIs should be rare, and we'd better off looking
for instances we can remove entirely.