Messages in this thread | | | Date | Wed, 17 Sep 2008 18:09:54 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [RFC 0/4] dynamically allocate arch specific system vectors |
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Eric W. Biederman wrote: >> It is one vector for each cpu. >> >> It is more efficient for software if the vector # is the same for all cpus > Why? Especially in terms of irq counting that would seem to lead to cache > line conflicts. > >> but the software/hardware can support a unique vector for each cpu. This >> assumes, of course, that the driver can determine the irq->vector mapping for >> each cpu. > > That sounds like you have a non-standard MSI-X vector. You certainly have all of > the same properties. At which point create_irq() sounds like what you want. > > One irq per cpu, per device. > > It is the trend. Don't worry all of the high performance drivers are doing it. > That is the path that will be optimized. >
In particular, it's just another interrupt type. We already have quite a few of those, from XT-PIC to the various IOAPIC ones, to MSI and MSI-X.
Just treating these as variants of MSI seems to me to make most sense, too.
-hpa
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