On Thu, Feb 12, 2009 at 08:50:32PM +0800, Yu Zhao wrote: > 2, avoid using pci_find_ext_capability every time when reading ATS > Invalidate Queue Depth (Matthew Wilcox) er ... I didn't say it was a problem. I said I couldn't tell if it was a problem. There's no point in taking up an extra 4 bytes per pci_dev if it's not a performance problem. How often do we query the queue depth? Is this something a device driver will call once per device and then remember for itself, or only use at setup? Or is it something we call every millisecond? -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html