On Tue, Feb 18, 2014 at 02:39:31PM -0500, Waiman Long wrote: > The #ifdef is harder to take away here. The point is that doing a 32-bit > exchange may accidentally steal the lock with the additional code to handle > that. Doing a 16-bit exchange, on the other hand, will never steal the lock > and so don't need the extra handling code. I could construct a function with > different return values to handle the different cases if you think it will > make the code easier to read.
Does it really pay to use xchg() with all those fixup cases? Why not have a single cmpxchg() loop that does just the exact atomic op you want? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
