From 1ebe6b81ebdba8faf377d1d7d84ad9368e7a0bae Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Thu, 26 Jul 2018 14:53:54 +1000 Subject: KVM: PPC: Book3S HV: Allow creating max number of VCPUs on POWER9 Commit 1e175d2 ("KVM: PPC: Book3S HV: Pack VCORE IDs to access full VCPU ID space", 2018-07-25) allowed use of VCPU IDs up to KVM_MAX_VCPU_ID on POWER9 in all guest SMT modes and guest emulated hardware SMT modes. However, with the current definition of KVM_MAX_VCPU_ID, a guest SMT mode of 1 and an emulated SMT mode of 8, it is only possible to create KVM_MAX_VCPUS / 2 VCPUS, because threads_per_subcore is 4 on POWER9 CPUs. (Using an emulated SMT mode of 8 is useful when migrating VMs to or from POWER8 hosts.) This increases KVM_MAX_VCPU_ID to 8 * KVM_MAX_VCPUS when HV KVM is configured in, so that a full complement of KVM_MAX_VCPUS VCPUs can be created on POWER9 in all guest SMT modes and emulated hardware SMT modes. Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/kvm_host.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 5b9e6608c5bf..906bcbdfd2a1 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -42,7 +42,14 @@ #define KVM_USER_MEM_SLOTS 512 #include -#define KVM_MAX_VCPU_ID (threads_per_subcore * KVM_MAX_VCORES) + +#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE +#include /* for MAX_SMT_THREADS */ +#define KVM_MAX_VCPU_ID (MAX_SMT_THREADS * KVM_MAX_VCORES) + +#else +#define KVM_MAX_VCPU_ID KVM_MAX_VCPUS +#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */ #define __KVM_HAVE_ARCH_INTC_INITIALIZED -- cgit v1.2.3