Marcelo Tosatti wrote: > Avi was concerned that this would cause problems with migration. I > haven't specifically tested it yet, but it seems there will be no > problems introduced by this change: the IO thread will stop all vcpu's > in the same way the vcpu0 thread did before. >
I believe this is broken for smp_cpus > 1, and will with this change will be broken even for non smp. The pause/resume logic is rotten. > QEMU/KVM: separate thread for IO handling > > Move IO processing from vcpu0 to a dedicated thread. > > This removes load on vcpu0 by allowing better cache locality and also > improves latency. > > We can now block signal handling for IO events, so sigtimedwait won't > race with handlers: > > - Currently the SIGALRM handler fails to set CPU_INTERRUPT_EXIT because > the "next_cpu" variable is not initialized in the KVM path, meaning that > processing of timer expiration might be delayed until the next vcpu0 exit. > I think we call main_loop_wait() is called unconditionally after every signal. > - Processing of IO events will not be unnecessarily interrupted. > > > Index: kvm-userspace.io/libkvm/libkvm.c > =================================================================== > --- kvm-userspace.io.orig/libkvm/libkvm.c > +++ kvm-userspace.io/libkvm/libkvm.c > @@ -388,9 +388,6 @@ int kvm_create(kvm_context_t kvm, unsign > if (r < 0) > return r; > kvm_create_irqchip(kvm); > - r = kvm_create_vcpu(kvm, 0); > - if (r < 0) > - return r; > > return 0; > } > Please put this and the corresponding qemu change in a separate patch. [...lots more...] Looks good. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
