Transformation of a program-event-recording event into a run-time instrumentation event

• US 9,442,824 B2
• Filed: 03/16/2012
• 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: Gainey, Charles W. Jr., Gschwind, Michael K.
• Primary Examiner(s): NGUYEN, DUY KHUONG THANH
• Application Number:
  US13/422,596
• Publication Number:
  US 20130247011A1
• Time in Patent Office: 1,642 Days
• Field of Search: 717/126, 717/130
• US Class Current: 1/1
• CPC Class Codes: G06F 11/3636 by tracing the execution of the program
• CPC Class Codes: G06F 11/3644 by instrumenting at runtime
• CPC Class Codes: G06F 11/3648 using additional hardware
• CPC Class Codes: G06F 8/31 Programming languages or programming paradigms

Abstract

Embodiments of the invention relate to transforming a program-event-recording event into a run-time instrumentation event. An aspect of the invention includes enabling run-time instrumentation for collecting instrumentation information of an instruction stream executing on a processor. Detecting is performed, by the processor, of a program-event-recording (PER) event, the PER event associated with the instruction stream executing on the processor. A PER event record is written to a collection buffer as a run-time instrumentation event based on detecting the PER event, the PER event record identifying the PER event.

Claims

1. A computer program product for transforming a program-event-recording event into a run-time instrumentation event, the computer program product comprising:

a non-transitory storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising;

configuring a run-time-instrumentation control based on executing a load run-time instrumentation controls (LRIC) instruction, the LRIC instruction enabling run-time instrumentation pro gram-event-recording (PER) controls;

granting permission to configure run-time instrumentation control values from a lower-privileged program;

granting permission to configure PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled;

enabling run-time instrumentation for collecting instrumentation information of an instruction stream executing on a processor;

detecting, by the processor, a PER event, the PER event associated with the instruction stream executing on the processor by intercepting a PER interruption condition associated with the PER event such that the instruction stream executing on the processor is not interrupted by a PER interruption associated with the PER interruption condition to prevent removal of knowledge of the PER event from a program associated with the instruction stream; and

writing a PER event record to a collection buffer as a run-time instrumentation event based on detecting the PER event, the PER event record identifying the PER event.

2. The computer program product of claim 1, wherein granting permission to configure run-time instrumentation control values from a lower-privileged program further comprises setting a K-bit based on executing the LRIC instruction to grant permission for execution of a modify run-time instrumentation controls (MRIC) instruction to configure run-time instrumentation control values from a lower-privileged program.

3. The computer program product of claim 2, wherein granting permission to configure the PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled further comprises setting a PK-bit based on executing the LRIC instruction to grant permission for execution of the MRIC instruction to configure the PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled and the K-bit is set.

4. The computer program product of claim 3, wherein the MRIC instruction updates a control block comprising a run-time instrumentation program-buffer current address (RCA) field, a run-time instrumentation program-buffer origin address (ROA) field, and a run-time instrumentation program-buffer limit address (RLA) field, and further comprising:

setting address values in the ROA field and the RLA field to configure a run-time instrumentation program buffer based on the MRIC instruction executed, wherein the PK-bit is clear and the K-bit is set; and

remapping one or more of the RCA field, the ROA field, and the RLA field to configure the PER control registers based on a subsequent MRIC instruction executed, wherein the PK-bit is set and the K-bit is set.

5. The computer program product of claim 1, further comprising:

setting a PI-bit based on executing the LRIC instruction to recognize an instruction causing the PER event as a sample instruction when the run-time instrumentation PER controls are enabled; and

storing a reporting group to a run-time instrumentation program buffer, the reporting group comprising the PER event record and an instruction-type record identifying an instruction causing the PER event as the sample instruction.

6. The computer program product of claim 1, wherein the PER event record comprises:

a PER code identifying the PER event, wherein the PER event is one of;

successful-branching, instruction-fetching, storage-alteration, store-using-real-address, and instruction-fetching nullification;

a PER address-space-control element identification used to translate a reference that caused the PER event;

a PER access identification;

a PER length of an instruction field; and

a PER address containing an instruction address used to fetch the instruction responsible for the PER event.

7. A system for transforming a program-event-recording event into a run-time instrumentation event, the system comprising:

a collection buffer; and

a processor comprising a run-time instrumentation module, the run-time instrumentation module configured to perform a method comprising;

configuring a run-time-instrumentation control based on executing a load run-time instrumentation controls (LRIC) instruction, the LRIC instruction enabling run-time instrumentation program-event-recording (PER) controls;

granting permission to configure run-time instrumentation control values from a lower-privileged program;

granting permission to configure PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled;

enabling run-time instrumentation for collecting instrumentation information of an instruction stream executing on the processor;

detecting, by the processor, a PER event, the PER event associated with the instruction stream executing on the processor by intercepting a PER interruption condition associated with the PER event such that the instruction stream executing on the processor is not interrupted by a PER interruption associated with the PER interruption condition to prevent removal of knowledge of the PER event from a program associated with the instruction stream; and

writing a PER event record to the collection buffer as a run-time instrumentation event based on detecting the PER event, the PER event record identifying the PER event.

8. The system of claim 7, wherein granting permission to configure run-time instrumentation control values from a lower-privileged program further comprises setting a K-bit based on executing the LRIC instruction to grant permission for execution of a modify run-time instrumentation controls (MRIC) instruction to configure run-time instrumentation control values from a lower-privileged program.

9. The system of claim 8, wherein granting permission to configure the PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled further comprises setting a PK-bit based on executing the LRIC instruction to grant permission for execution of the MRIC instruction to configure the PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled and the K-bit is set.

10. The system of claim 9, wherein the MRIC instruction updates a control block comprising a run-time instrumentation program-buffer current address (RCA) field, a run-time instrumentation program-buffer origin address (ROA) field, and a run-time instrumentation program-buffer limit address (RLA) field, and further comprising:

setting address values in the ROA field and the RLA field to configure a run-time instrumentation program buffer based on the MRIC instruction executed, wherein the PK-bit is clear and the K-bit is set; and

remapping one or more of the RCA field, the ROA field, and the RLA field to configure the PER control registers based on a subsequent MRIC instruction executed, wherein the PK-bit is set and the K-bit is set.

11. The system of claim 7, further comprising:

setting a PI-bit based on executing the LRIC instruction to recognize an instruction causing the PER event as a sample instruction when the run-time instrumentation PER controls are enabled; and

storing a reporting group to a run-time instrumentation program buffer, the reporting group comprising the PER event record and an instruction-type record identifying an instruction causing the PER event as the sample instruction.

12. The system of claim 7, wherein the PER event record comprises:

a PER code identifying the PER event, wherein the PER event is one of;

successful-branching, instruction-fetching, storage-alteration, store-using-real-address, and instruction-fetching nullification;

a PER address-space-control element identification used to translate a reference that caused the PER event;

a PER access identification;

a PER length of an instruction field; and

a PER address containing an instruction address used to fetch the instruction responsible for the PER event.

13. A computer program product for transforming a program-event-recording event into a run-time instrumentation event, the computer program product comprising:

a non-transitory storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising;

configuring a run-time-instrumentation control based on executing a load run-time instrumentation controls (LRIC) instruction, the LRIC instruction enabling run-time instrumentation program-event-recording (PER) controls;

setting a K-bit based on executing the LRIC instruction to grant permission for execution of a modify run-time instrumentation controls (MRIC) instruction to configure run-time instrumentation control values from a lower-privileged program;

setting a PK-bit based on executing the LRIC instruction to grant permission for execution of the MRIC instruction to configure PER control registers from the lower-privileged program when the run-time instrumentation PER controls are enabled and the K-bit is set;

enabling run-time instrumentation for collecting instrumentation information of an instruction stream executing on a processor;

detecting, by the processor, a PER event, the PER event associated with the instruction stream executing on the processor; and

writing a PER event record to a collection buffer as a run-time instrumentation event based on detecting the PER event, the PER event record identifying the PER event.

14. The computer program product of claim 13, wherein detecting the PER event further comprises:

intercepting a PER interruption condition associated with the PER event such that the instruction stream executing on the processor is not interrupted by a PER interruption associated with the PER interruption condition.

15. The computer program product of claim 13, wherein the MRIC instruction updates a control block comprising a run-time instrumentation program-buffer current address (RCA) field, a run-time instrumentation program-buffer origin address (ROA) field, and a run-time instrumentation program-buffer limit address (RLA) field, and further comprising:

setting address values in the ROA field and the RLA field to configure a run-time instrumentation program buffer based on the MRIC instruction executed, wherein the PK-bit is clear and the K-bit is set; and

remapping one or more of the RCA field, the ROA field, and the RLA field to configure the PER control registers based on a subsequent MRIC instruction executed, wherein the PK-bit is set and the K-bit is set.

16. The computer program product of claim 13, further comprising:

setting a PI-bit based on executing the LRIC instruction to recognize an instruction causing the PER event as a sample instruction when the run-time instrumentation PER controls are enabled; and

storing a reporting group to a run-time instrumentation program buffer, the reporting group comprising the PER event record and an instruction-type record identifying an instruction causing the PER event as the sample instruction.

17. The computer program product of claim 13, wherein the PER event record comprises:

a PER code identifying the PER event, wherein the PER event is one of;

successful-branching, instruction-fetching, storage-alteration, store-using-real-address, and instruction-fetching nullification;

a PER address-space-control element identification used to translate a reference that caused the PER event;

a PER access identification;

a PER length of an instruction field; and

a PER address containing an instruction address used to fetch the instruction responsible for the PER event.