> -----Original Message----- > From: Sarah Sharp [mailto:sarah.a.sharp@xxxxxxxxxxxxxxx] > Sent: Wednesday, June 15, 2011 11:31 AM > To: Xu, Andiry > Cc: linux-usb@xxxxxxxxxxxxxxx; matthew.r.wilcox@xxxxxxxxx > Subject: Re: [PATCH 4/5] xHCI: Enable multiple interrupters > > On Fri, Jun 10, 2011 at 04:51:42PM +0800, Andiry Xu wrote: > > This patch enables all the interrupters allocated, so devices can use > > different interrupters and got interrupt from them. When an interrupt > > is triggered, the irq handler only checks the corresponding > interrupter > > and event ring. > > > > When using MSI-X, the number of interrupters enabled will be equal to > > xhci->msix_count; When using MSI or PCI INTx, the number of > interrupters > > enabled will be 1. > > Why only allocate one event ring when only MSI, not MSI-X is enabled? > You should be able to use multiple event rings, but all the interrupts > will be directed to the same CPU, correct? I think you could still see > performance gains if you have an MSI-only host but you could direct > different types of USB traffic to different event rings with different > interrupt modulation rates. > > I think this was something Matthew wanted for the UAS driver for the > hosts that only supported MSI. For those hosts, could you register, > say, 5 event rings with the same interrupter? Matthew, do you think > that's enough, or do you want more? > Are you sure one interrupter can has multiple event rings? As I know, one interrupter has one interrupter register set, and only has one event ring. Thanks, Andiry -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
