tree 8350e79b1b046374a5b4658dc498a3f8b1e8b8f5
parent 80f0e95d1b221688b2608e0a80134e7acccd9a89
author Eugene Korenevsky <ekorenevsky@gmail.com> 1427662572 +0300
committer Paolo Bonzini <pbonzini@redhat.com> 1428482816 +0200

KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu

cpuid_maxphyaddr(), which performs lot of memory accesses is called
extensively across KVM, especially in nVMX code.

This patch adds a cached value of maxphyaddr to vcpu.arch to reduce the
pressure onto CPU cache and simplify the code of cpuid_maxphyaddr()
callers. The cached value is initialized in kvm_arch_vcpu_init() and
reloaded every time CPUID is updated by usermode. It is obvious that
these reloads occur infrequently.

Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
Message-Id: <20150329205612.GA1223@gnote>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>