Re: When should we use likely() / unlikely() / get_unaligned() ?

[Rusty Russell]

In message <1076238833.12587.229.camel@xxxxxxxxxxxxxxxxxxxx> you write:
> To be honest, I'm more interested in the case of get_unaligned(). The
> principle is fairly similar -- the ratio between the performance of the
> inline and the exception cases varies wildly from architecture to
> architecture. But the range is far wider -- we now support architectures
> in 2.6 where alignment fixups _cannot_ happen, and the cost of the
> 'exception' case should be considered infinite.

Um, we do?  I thought it was compulsory in the kernel, otherwise
networking breaks on packets w/ wierd hardware headers.

Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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