On Mon, 9 Nov 2015, Qais Yousef wrote: > On 11/07/2015 01:31 PM, Thomas Gleixner wrote: > > On Tue, 3 Nov 2015, Qais Yousef wrote: > > > + > > > + /* always allocate a virq per cpu */ > > > + nr_irqs = ipi_mask_weight(dest); > > That's not really a good assumption. Not all architectures need > > seperate interrupt numbers / descriptors because they can allocate > > from a per cpu interrupt space. We really want to handle that here as > > well. So we need a flag in the IPI domain which tells us whether that > > allocation needs to be weight(desc) or 1. > > OK. But is it bad to always allocate the weight? I thought allocating virqs is > cheap, or maybe not? It's wrong to allocate the descriptors in the case of per cpu interrupts. Aside of wasting memory its not representing what the hardware does. Thanks, tglx
