On Thu, 2008-07-03 at 14:41 +1000, Benjamin Herrenschmidt wrote: > On Wed, 2008-07-02 at 21:59 -0600, Matthew Wilcox wrote: > > > > > > This is true and worth considering carefully. Are IRQ numbers a scarce > > resource on PowerPC? They are considerably less scarce than interrupt > > vectors are on x86-64. How hard is it to make IRQ numbers an abundent > > resource? Is it simply a question of increasing NR_IRQS? > > Yes, indeed, they aren't really scarce... actually less than the > underlying HW vectors in most cases, so it isn't a big issue to add some > kind of constraint to the allocator. Not scarce, but increasing NR_IRQS makes some static arrays bigger, which is not so nice. > > By the way, would people be interested in changing the MSI-X API to get > > rid of the msix_entry array? If allocating consecutive IRQs isn't a > > problem, then we could switch the MSI-X code to use consecutive IRQs. > > It would make a lot of code simpler... It's not a pretty API to be sure. I thought drivers needed the flexibility of being able to specify non-contiguous ranges. In practice it looks like only s2io is doing anything different. cheers -- Michael Ellerman OzLabs, IBM Australia Development Lab email: michaele@xxxxxxxxxx stime: ellerman@xxxxxxxxxxx notes: Michael Ellerman/Australia/IBM phone: +61 2 6212 1183 (tie line 70 21183) We do not inherit the earth from our ancestors, we borrow it from our children. - S.M.A.R.T Person -- 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
