An exclusion controller which allows an information processing unit to
acquire a contended resource to the exclusion of the other information
processing units includes a plurality of non-prioritized information
processing units mutually exclusively acquiring a non-prioritized
exclusion right, which indicates a candidate for acquiring the contended
resource, by a first process. The exclusion controller further includes a
prioritized information processing unit acquiring the contended resource
by a second process, which requires a shorter processing time than the
first process, to the exclusion of the non-prioritized information
processing unit having acquired the non-prioritized exclusion right.