diff options
| author | Greg Kurz <gkurz@linux.vnet.ibm.com> | 2016-05-09 18:13:37 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-05-11 22:37:54 +0200 |
| commit | 0b1b1dfd52a67f4f09a18cb82337199bc90ad7fb (patch) | |
| tree | 7d4ec00b96a96ef12fe3aeab042de758451e1bd4 /include/linux/kvm_host.h | |
| parent | 9b9e3fc4d5a31f6050508f2404369beac4356867 (diff) | |
kvm: introduce KVM_MAX_VCPU_ID
The KVM_MAX_VCPUS define provides the maximum number of vCPUs per guest, and
also the upper limit for vCPU ids. This is okay for all archs except PowerPC
which can have higher ids, depending on the cpu/core/thread topology. In the
worst case (single threaded guest, host with 8 threads per core), it limits
the maximum number of vCPUS to KVM_MAX_VCPUS / 8.
This patch separates the vCPU numbering from the total number of vCPUs, with
the introduction of KVM_MAX_VCPU_ID, as the maximal valid value for vCPU ids
plus one.
The corresponding KVM_CAP_MAX_VCPU_ID allows userspace to validate vCPU ids
before passing them to KVM_CREATE_VCPU.
This patch only implements KVM_MAX_VCPU_ID with a specific value for PowerPC.
Other archs continue to return KVM_MAX_VCPUS instead.
Suggested-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'include/linux/kvm_host.h')
| -rw-r--r-- | include/linux/kvm_host.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 0a0e00d9c5da..352889d6e322 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -35,6 +35,10 @@ #include <asm/kvm_host.h> +#ifndef KVM_MAX_VCPU_ID +#define KVM_MAX_VCPU_ID KVM_MAX_VCPUS +#endif + /* * The bit 16 ~ bit 31 of kvm_memory_region::flags are internally used * in kvm, other bits are visible for userspace which are defined in |