Glauber de Oliveira Costa wrote: > I'm sending a first draft of my proposed cpu hotplug driver for kvm/virtio > The first patch is the kernel module, while the second, the userspace pci > device. > > The host boots with the maximum cpus it should ever use, through the -smp > parameter. > Due to real machine constraints (which qemu copies), i386 does not allow for > any addition > of cpus after boot, so this is the most general way. > > I do however, include an "attempt_buffer" in the userspace part. It's purpose > is to > allow tools like virt-manager to set a max_cpus (-smp), and a desired number > of cpus > in their configuration files. (and AFAICT, there's is no easy way for them to > tell when the > backend driver is up and running) > > Other than that, it should be pretty much straightforward. > > Looking forward for your comments > >
I would much prefer to see cpu hotplug implemented via acpi. Such an implementation would work on older kernels without change, and will also work with other operating systems. It isn't a high-speed interface so virtio doesn't buy us anything. Linux appears to support it (CONFIG_ACPI_HOTPLUG_CPU) so all that's needed is the host side support (likely qemu/bios only). Of course hacking on acpi is fun, if you're the kind of person than enjoys dental surgery. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
