Ming, On Mon, 18 Feb 2019, Ming Lei wrote: > On Sun, Feb 17, 2019 at 08:17:05PM +0100, Thomas Gleixner wrote: > > I don't see how that would break blk-mq. The unmanaged set is not used by > > the blk-mq stuff, that's some driver internal voodoo. So blk-mq still gets > > a perfectly spread and managed interrupt set for the queues. > > >From the discussion above, the use case is for megaraid_sas. And one of the > two interrupt sets(managed and non-managed) will be chosen according to > workloads runtime. > > Each interrupt set actually defines one blk-mq queue mapping, and the > queue mapping needs to respect the rule I mentioned now. However, > non-managed affinity can be changed to any way anytime by user-space. > > Recently HPSA tried to add one module parameter to use non-managed > IRQ[1]. > > Also NVMe RDMA uses non-managed interrupts, and at least one CPU hotplug > issue is never fixed yet[2]. > > [1] https://marc.info/?t=154387665200001&r=1&w=2 > [2] https://www.spinics.net/lists/linux-block/msg24140.html Interesting. I misread the description which megasas folks provided then. I'll drop that patch and get the other lot merged. Thanks for your work and help with that! Thanks, tglx
