A processor 106 with multiple threads is provided with a profiling unit 104 to monitor each thread for anomalous activity. The profiling unit is configured to profile the operation of the processing unit over a period of time to generate an activity profile indicating when each of the processor threads is being executed by the processing unit. The profiling unit then analyses the generated activity profile to determine if a signature of the processing unit’s thread execution matches that of a baseline signature, if the two signatures do not match then an alert signal is outputted. The activity profile may indicate the number of processing unit clock cycles that have been spent executing each thread over the time period. The profiling unit may be configured to identify each thread being executed over the time period in order to generate the activity profile, each thread may then be monitored by using sideband signals or a storage location indicating the thread which is being executed. If the system is on an integrated circuit chip, then the profiling unit may monitor transactions over the interconnect circuitry 204.
展开▼
