Messages in this thread | | | Date | Thu, 1 Apr 2004 14:29:12 +0200 (CEST) | From | "Maciej W. Rozycki" <> | Subject | Re: [ACPI] Re: Linux 2.4.26-rc1 (cmpxchg vs 80386 build) |
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On Wed, 31 Mar 2004, Jamie Lokier wrote:
> > Well, "cmpxchg", "xadd", etc. can be easily emulated with an aid of a > > spinlock. With SMP operation included. > > Nope. Len Brown wrote: > > > Linux uses this locking mechanism to coordinate shared access > > to hardware registers with embedded controllers, > > which is true also on uniprocessors too. > > You can't do that with a spinlock. The embedded controllers would > need to know about the spinlock.
Hmm, does it mean we support x86 systems where an iomem resource has to be atomically accessible by a CPU and a peripheral controller?
-- + Maciej W. Rozycki, Technical University of Gdansk, Poland + +--------------------------------------------------------------+ + e-mail: macro@ds2.pg.gda.pl, PGP key available + - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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