No, please don't.
Just don't take this whole patch-series until it's cleaned up. There is
absolutely no excuse for using xchg as a locking primitive. Nothing like
this should be queued anywhere, it should be burned and the ashes should
be scattered over the atlantic so that nobody will ever see them again.
F*ck me with a spoon, if you have to use xchg() to do a trylock, why the
hell isn't the unlock sequence then
smp_mb();
var = 0;
instead? Not that that's really right either, but at least it avoids the
_ridiculous_ crap. The real solution is probably to use a spinlock and
trylock/unlock.
Linus
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