Re: Fix locking in input

From: Manfred Spraul
Date: Sun Nov 23 2003 - 17:55:27 EST


Russell King wrote:

On Sun, Nov 23, 2003 at 11:24:02PM +0100, Manfred Spraul wrote:


I think one platform (early ARM?) cannot access bytes directly, and implement the access with read 16-bit, change 8-bit, write back 16 bit.


Nope.

It seems it's Alpha:

On Thu, 28 Dec 2000, Linus wrote:

FreeBSD doesn't try to be portable any more, but Linux does, and there are
architectures where 8- and 16-bit accesses aren't *atomic* but have to be
done with read-modify-write cycles.

And even for fields like "age", where we don't care whether the age itself
is 100% accurate, we _do_ care that the fields close-by don't get strange
effects from updating "age". We used to have exactly this problem on alpha
back in the 2.1.x timeframe.



--
Manfred

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/