Run-time instrumentation indirect sampling by instruction operation code

• US 9,442,728 B2
• Filed: 03/05/2013
• Issued: 09/13/2016
• Est. Priority Date: 03/16/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bradbury, Jonathan D., Gainey, Charles W. Jr., Gschwind, Michael K., Schwarz, Eric M.
• Primary Examiner(s): NGUYEN, DUY KHUONG THANH
• Application Number:
  US13/784,868
• Publication Number:
  US 20130246772A1
• Time in Patent Office: 1,288 Days
• Field of Search: 717/126, 717/130
• US Class Current: 1/1
• CPC Class Codes: G06F 11/3466 Performance evaluation by tracing or monitoring
• CPC Class Codes: G06F 11/348 Circuit details, i.e. tracer hardware
• CPC Class Codes: G06F 11/3644 by instrumenting at runtime
• CPC Class Codes: G06F 2201/86 Event-based monitoring
• CPC Class Codes: G06F 2201/88 Monitoring involving counting
• CPC Class Codes: G06F 9/3005 to perform operations for flow control
• CPC Class Codes: G06F 9/30058 Conditional branch instructions
• CPC Class Codes: G06F 9/30145 Instruction analysis, e.g. decoding, instruction word fields

Abstract

Embodiments of the invention relate to implementing run-time instrumentation indirect sampling by instruction operation code. An aspect of the invention includes a method for implementing run-time instrumentation indirect sampling by instruction operation code. The method includes reading sample-point instruction operation codes from a sample-point instruction array, and comparing, by a processor, the sample-point instruction operation codes to an operation code of an instruction from an instruction stream executing on the processor. The method also includes recognizing a sample point upon execution of the instruction with the operation code matching one of the sample-point instruction operation codes. The run-time instrumentation information is obtained from the sample point. The method further includes storing the run-time instrumentation information in a run-time instrumentation program buffer as a reporting group.

Claims

1. A computer implemented method for implementing run-time instrumentation indirect sampling by instruction operation code, the method comprising:

initializing a run-time-instrumentation control based on executing a load run-time instrumentation controls (LRIC) instruction, the LRIC instruction establishing a sampling mode and a sample-point instruction (SPI) control, wherein the SPI control is a field in a load control block loadable as an operand of the LRIC instruction, and the SPI control enables indirect sampling by instruction operation code as an additional sampling mode in combination with one or more of directed sampling and interval-based sampling;

reading sample-point instruction operation codes from a sample-point instruction array, the sample-point instruction array comprising a part of a register in a processor;

comparing, by the processor, the sample-point instruction operation codes to an operation code of an instruction from an instruction stream executing on the processor, the operation code defining an operation to be executed by the processor;

recognizing a sample point upon execution of the instruction, by the processor, with the operation code matching one of the sample-point instruction operation codes, wherein run-time instrumentation information is obtained from the sample point; and

storing the run-time instrumentation information in a run-time instrumentation program buffer as a reporting group.

2. The method of claim 1, wherein the run-time instrumentation information comprises run-time instrumentation event records collected in a collection buffer of the processor and the reporting group further comprises system information records in combination with the run-time instrumentation event records.

3. The method of claim 2, wherein the instruction with the operation code matching one of the sample-point instruction operation codes is identified as a sample instruction in an instruction record of the reporting group.

4. The method of claim 1, further comprising:

fetching a run-time instrumentation load sample point instructions (RILSPI) instruction establishing the sample-point instruction operation codes; and

executing the RILSPI instruction by the processor, the executing comprising;

storing the sample-point instruction operation codes in the sample-point instruction array; and

updating a condition code in the processor based on the storing.

5. The method of claim 1, further comprising:

fetching a run-time instrumentation store sample point instructions (RISSPI) instruction comprising a storage address; and

executing the RISSPI instruction by the processor, the executing comprising;

reading the sample-point instruction operation codes from the sample-point instruction array; and

storing the sample-point instruction operation codes to a location identified by the storage address.

6. The method of claim 1, further comprising:

fetching a run-time instrumentation clear sample point instructions (RICSPI); and

executing the RICSPI instruction by the processor, the executing comprising;

clearing the sample-point instruction operation codes in the sample-point instruction array; and

updating a condition code in the processor based on the clearing.