[PATCH] Document Linux's memory barriers [try #2]
David Howells
dhowells at redhat.com
Thu Mar 9 04:04:51 EST 2006
Alan Cox <alan at redhat.com> wrote:
> [For information on bus mastering DMA and coherency please read ....]
>
> sincee have a doc on this
Documentation/pci.txt?
> The use of volatile generates poorer code and hides the serialization in
> type declarations that may be far from the code.
I'm not sure what you mean by that.
> Is this true of IA-64 ??
Are you referring to non-temporal loads and stores?
> > +There are some more advanced barriering functions:
>
> "barriering" ... ick, barrier.
Picky:-)
> Should clarify local ordering v SMP ordering for locks implied here.
Do you mean explain what each sort of lock does?
> > + (*) inX(), outX():
> > +
> > + These are intended to talk to legacy i386 hardware using an alternate bus
> > + addressing mode. They are synchronous as far as the x86 CPUs are
>
> Not really true. Lots of PCI devices use them. Need to talk about "I/O space"
Which bit is not really true?
David
More information about the Linuxppc64-dev
mailing list