Preventing loss of traced information in a data processing apparatus

Abstract

Techniques for preventing the loss of trace information being transmitted via trace infrastructure are disclosed. A data processing apparatus for processing instructions is provided. The data processing apparatus comprises: decode/issue logic operable to receive and decode an instruction to be processed by the data processing apparatus and to determine when to issue a decoded instructions for execution by execution logic; execution logic operable to execute the decoded instructions; interface logic selectively operable to receive trace information relating to the state of the data processing apparatus generated in response to execution of the decoded instructions for transmission to trace monitoring infrastructure; and throttle logic operable to predict whether issuing the decoded instruction to the execution logic for execution would be likely to cause the trace information to be transmitted to said trace monitoring infrastructure to exceed a capacity of said trace monitoring infrastructure and, if so, to prevent the decode/issue logic from issuing the decoded instruction to the execution logic. Accordingly, the throttle logic reviews each instruction to be executed and predicts whether issuing that instruction at that time will or is likely to cause the capacity to be exceeded. In the event that the throttle logic determines that the capacity is likely to be exceeded, the instruction is prevented from being issued to the execution logic which reduces the likelihood that any state information is lost.