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SubjectRe: [PATCH 01/16] hpsa: do readl after writel in main i/o path to ensure commands don't get lost.
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On Wed, 04 May 2011 11:37:35 MDT, Matthew Wilcox said:
> > This probably needs a comment like
> > /* don't care - dummy read just to force write posting to chipset */
> > or similar. I'm assuming it's just functioning as a barrier-type flush of some sort?
>
> It's a PCI write flush. It's not clear to me why it's needed here,
> though. The write will eventually get to the device; why we need to
> make the CPU wait around for it to actually get there doesn't make sense.

Exactly why I think it needs a one-liner comment. :)


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