Re: Opinion on ordering of writel vs. stores to RAM

From: David Miller
Date: Mon Sep 11 2006 - 20:28:18 EST


From: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 11 Sep 2006 16:17:18 +0200

> >> Why not just keep writel() etc. for *both* purposes; the address
> >> cookie
> >> it gets as input can distinguish between the required behaviours for
> >> different kinds of I/Os; it will have to be setup by the arch-
> >> specific
> >> __ioremap() or similar.
> >
> > This doesn't work when the I/O semantics are encoded into the
> > instruction, not some virual mapping PTE bits. We'll have to use
> > a conditional or whatever in that case, which is silly.
>
> Why is this "silly"?

It's silly because if you just use different interface
names for the different semantics, the caller can
ask for what he wants at the call site and no conditionals
are needed in the implementation.

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