On Fri, 28 Sep 2007, Alan Cox wrote:
>
> However
> - You've not shown the patch has any performance gain
It would be nice to see this.
> - You've probably broken Pentium Pro
Probably not a big deal, but yeah, we should have that broken-ppro option.
> - and for modern processors its still not remotely clear your patch is
> correct because of NT stores.
This one I disagree with. The *old* code doesn't honor NT stores *either*.
The fact is, if you use NT stores and then depend on ordering, it has
nothing what-so-ever to do with spinlocks or smp_[rw]mb. You need to use
the DMA barriers (ie the non-smp ones).
The non-temporal stores should be basically considered to be "IO", not any
normal memory operation.
Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]