> So that nobody else would waste any time on this, attached is a new > attempt. This time actually tested *after* the changes. So I've picked up your patch (vfs.misc). It's clever alright so thanks for the comments in there otherwise I would've stared at this for far too long. It's a little unpleasant because of the cast-orama going on before we check the file pointer but I don't see that it's in any way wrong. And given how focussed people are with __fget_* performance I think it might even be the right thing to do. But the cleverness means we have the same logic slightly differently twice. Not too bad ofc but not too nice either especially because that rcu lookup is pretty complicated already. A few days ago I did just write a long explanatory off-list email to someone who had questions about this and who is fairly experienced so we're not making it easy on people. But performance or simplicity; one can't necessarily always have both.
