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In order to quantify demand paging performance, time guest execution
during demand paging.
Signed-off-by: Ben Gardon <bgardon@google.com>
[Move timespec-diff to test_util.h]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>