Abstract: Processor time accounting is enhanced by per-thread internal resource usage counter circuits that account for usage of processor core resources to the threads that use them. Relative resource use can be determined by detecting events such as instruction dispatches for multiple threads active within the processor, which may include idle threads that are still occupying processor resources. The values of the resource usage counters are used periodically to determine relative usage of the processor core by the multiple threads. If all of the events are for a single thread during a given period, the processor time is allocated to the single thread. If no events occur in the given period, then the processor time can be equally allocated among threads. If multiple threads are generating events, a fractional resource usage can be determined for each thread and the counters may be updated in accordance with their fractional usage.

Abstract: Techniques are provided for determining consequences of an injected fault on a system running a given application program or operating system, in order to measure the software impact of a hardware soft error on the application program/operating system. The application program software is emulated instruction-by-instruction, where source operands are randomly modified before an instruction is executed, and destination operands are randomly modified after an instruction is executed, in order to mimic hardware soft errors. In addition, a program counter is randomly modified after execution of a branch instruction. The resulting consequences of such modifications are monitored such that a fault of an instruction being executed is modeled in order to determine a soft error rate (SER) for a software application program or operating system.

Abstract: A technique for triggering a system bus write command with user code includes identifying a specific store-type instruction in a user instruction sequence. The specific store-type instruction is converted into a specific request-type command, which is configured to include core permission controls (that are stored in core configuration registers of a processor core by a trusted kernel) and user created data (stored in a cache memory). Slave devices are configured through register space (that is only accessible by the trusted kernel) with respective slave permission controls. The specific request-type command is then transmitted from the cache memory, via a system bus. In this case, the slave devices that receive the specific request-type command process the specific request-type command when the core permission controls are the same as the respective slave permission controls. The trusted kernel may be included in a hypervisor or an operating system.

Abstract: Processor time accounting is enhanced by per-thread internal resource usage counter circuits that account for usage of processor core resources to the threads that use them. Relative resource use can be determined by detecting events such as instruction dispatches for multiple threads active within the processor, which may include idle threads that are still occupying processor resources. The values of the resource usage counters are used periodically to determine relative usage of the processor core by the multiple threads. If all of the events are for a single thread during a given period, the processor time is allocated to the single thread. If no events occur in the given period, then the processor time can be equally allocated among threads. If multiple threads are generating events, a fractional resource usage can be determined for each thread and the counters may be updated in accordance with their fractional usage.

Abstract: A system, method, and product are disclosed for testing multiple threads simultaneously. The threads share a real memory space. A first portion of the real memory space is designated as exclusive memory such that the first portion appears to be reserved for use by only one of the threads. The threads are simultaneously executed. The threads access the first portion during execution. Apparent exclusive use of the first portion of the real memory space is permitted by a first one of the threads. Simultaneously with permitting apparent exclusive use of the first portion by the first one of the threads, apparent exclusive use of the first portion of the real memory space is also permitted by a second one of the threads. The threads simultaneously appear to have exclusive use of the first portion and may simultaneously access the first portion.

Abstract: Processor time accounting is enhanced by per-thread internal resource usage counter circuits that account for usage of processor core resources to the threads that use them. Relative resource use can be determined by detecting events such as instruction dispatches for multiple threads active within the processor, which may include idle threads that are still occupying processor resources. The values of the resource usage counters are used periodically to determine relative usage of the processor core by the multiple threads. If all of the events are for a single thread during a given period, the processor time is allocated to the single thread. If no events occur in the given period, then the processor time can be equally allocated among threads. If multiple threads are generating events, a fractional resource usage can be determined for each thread and the counters may be updated in accordance with their fractional usage.

Abstract: A system, method, and product are disclosed for testing multiple threads simultaneously. The threads share a real memory space. A first portion of the real memory space is designated as exclusive memory such that the first portion appears to be reserved for use by only one of the threads. The threads are simultaneously executed. The threads access the first portion during execution. Apparent exclusive use of the first portion of the real memory space is permitted by a first one of the threads. Simultaneously with permitting apparent exclusive use of the first portion by the first one of the threads, apparent exclusive use of the first portion of the real memory space is also permitted by a second one of the threads. The threads simultaneously appear to have exclusive use of the first portion and may simultaneously access the first portion.

Abstract: A processor interleaves instructions according to a priority rule which determines the frequency with which instructions from each respective thread are selected and added to an interleaved stream of instructions to be processed in the data processor. The frequency with which each thread is selected according to the rule may be based on the priorities assigned to the instruction threads. A randomization is inserted into the interleaving process so that the selection of an instruction thread during any particular clock cycle is not based solely by the priority rule, but is also based in part on a random or pseudo random element. This randomization is inserted into the instruction thread selection process so as to vary the order in which instructions are selected from the various instruction threads while preserving the overall frequency of thread selection (i.e. how often threads are selected) set by the priority rule.

Abstract: In accordance with an aspect of the present invention, specifying a portion of a circuit design to be treated as untimed by static timing analysis is performed on the RTL design by means of an attribute annotation. The process is operable to map through to the Physical Design by correlating latches and chip-level nets. This allows the testing process to become closed-loop. Design and simulation time is also greatly reduced due to the accessibility of RTL design.

Abstract: Each instruction thread in a SMT processor is associated with a software assigned base input processing priority. Unless some predefined event or circumstance occurs with an instruction being processed or to be processed, the base input processing priorities of the respective threads are used to determine the interleave frequency between the threads according to some instruction interleave rule. However, upon the occurrence of some predefined event or circumstance in the processor related to a particular instruction thread, the base input processing priority of one or more instruction threads is adjusted to produce one more adjusted priority values. The instruction interleave rule is then enforced according to the adjusted priority value or values together with any base input processing priority values that have not been subject to adjustment.

Abstract: A technique for triggering a system bus write command with user code includes identifying a specific store-type instruction in a user instruction sequence. The specific store-type instruction is converted into a specific request-type command, which is configured to include core permission controls (that are stored in core configuration registers of a processor core by a trusted kernel) and user created data (stored in a cache memory). Slave devices are configured through register space (that is only accessible by the trusted kernel) with respective slave permission controls. The specific request-type command is then transmitted from the cache memory, via a system bus. In this case, the slave devices that receive the specific request-type command (via the system bus) process the specific request-type command when the core permission controls are the same as the respective slave permission controls.

Abstract: In accordance with an aspect of the present invention, the method for specifying a portion of a circuit design to be treated as untimed by static timing analysis is performed on the RTL design by means of an attribute annotation. The process is operable to map through to the Physical Design by correlating latches and chip-level nets. This allows the testing process to become closed-loop. Design and simulation time is also greatly reduced due to the accessibility of RTL design.

Abstract: Processor time accounting is enhanced by per-thread internal resource usage counter circuits that account for usage of processor core resources to the threads that use them. Relative resource use can be determined by detecting events such as instruction dispatches for multiple threads active within the processor, which may include idle threads that are still occupying processor resources. The values of the resource usage counters are used periodically to determine relative usage of the processor core by the multiple threads. If all of the events are for a single thread during a given period, the processor time is allocated to the single thread. If no events occur in the given period, then the processor time can be equally allocated among threads. If multiple threads are generating events, a fractional resource usage can be determined for each thread and the counters may be updated in accordance with their fractional usage.

Abstract: An accounting method and multi-threaded processor include a mechanism for accounting for processor resource usage by threads within programs. Relative resource use is determined by detecting a particular cycle state of threads active within the processor. If instructions are dispatched for all threads or no threads, the processor cycle is accounted equally to all threads. Alternatively if no threads are in the particular cycle state, the accounting may be made using a prior state, or in conformity with ratios of the threads' priority levels. If only one thread is in the particular cycle state, that thread is accounted the entire processor cycle. If multiple threads are dispatching, but less than all threads are dispatching, the processor cycle is billed evenly across the dispatching threads.

Abstract: Techniques are provided for determining consequences of an injected fault on a system running a given application program or operating system, in order to measure the software impact of a hardware soft error on the application program/operating system. The application program software is emulated instruction-by-instruction, where source operands are randomly modified before an instruction is executed, and destination operands are randomly modified after an instruction is executed, in order to mimic hardware soft errors. In addition, a program counter is randomly modified after execution of a branch instruction. The resulting consequences of such modifications are monitored such that a fault of an instruction being executed is modeled in order to determine a soft error rate (SER) for a software application program or operating system.

Abstract: A system, method, and product are disclosed for testing multiple threads simultaneously. The threads share a real memory space. A first portion of the real memory space is designated as exclusive memory such that the first portion appears to be reserved for use by only one of the threads. The threads are simultaneously executed. The threads access the first portion during execution. Apparent exclusive use of the first portion of the real memory space is permitted by a first one of the threads. Simultaneously with permitting apparent exclusive use of the first portion by the first one of the threads, apparent exclusive use of the first portion of the real memory space is also permitted by a second one of the threads. The threads simultaneously appear to have exclusive use of the first portion and may simultaneously access the first portion.

Abstract: A processor interleaves instructions according to a priority rule which determines the frequency with which instructions from each respective thread are selected and added to an interleaved stream of instructions to be processed in the data processor. The frequency with which each thread is selected according to the rule may be based on the priorities assigned to the instruction threads. A randomization is inserted into the interleaving process so that the selection of an instruction thread during any particular clock cycle is not based solely by the priority rule, but is also based in part on a random or pseudo random element. This randomization is inserted into the instruction thread selection process so as to vary the order in which instructions are selected from the various instruction threads while preserving the overall frequency of thread selection (i.e. how often threads are selected) set by the priority rule.

Abstract: A system, method, and product are disclosed for testing multiple threads simultaneously. The threads share a real memory space. A first portion of the real memory space is designated as exclusive memory such that the first portion appears to be reserved for use by only one of the threads. The threads are simultaneously executed. The threads access the first portion during execution. Apparent exclusive use of the first portion of the real memory space is permitted by a first one of the threads. Simultaneously with permitting apparent exclusive use of the first portion by the first one of the threads, apparent exclusive use of the first portion of the real memory space is also permitted by a second one of the threads. The threads simultaneously appear to have exclusive use of the first portion and may simultaneously access the first portion.

Abstract: A processor interleaves instructions according to a priority rule which determines the frequency with which instructions from each respective thread are selected and added to an interleaved stream of instructions to be processed in the data processor. The frequency with which each thread is selected according to the rule may be based on the priorities assigned to the instruction threads. A randomization is inserted into the interleaving process so that the selection of an instruction thread during any particular clock cycle is not based solely by the priority rule, but is also based in part on a random or pseudo random element. This randomization is inserted into the instruction thread selection process so as to vary the order in which instructions are selected from the various instruction threads while preserving the overall frequency of thread selection (i.e. how often threads are selected) set by the priority rule.

Abstract: Each instruction thread in a SMT processor is associated with a software assigned base input processing priority. Unless some predefined event or circumstance occurs with an instruction being processed or to be processed, the base input processing priorities of the respective threads are used to determine the interleave frequency between the threads according to some instruction interleave rule. However, upon the occurrence of some predefined event or circumstance in the processor related to a particular instruction thread, the base input processing priority of one or more instruction threads is adjusted to produce one more adjusted priority values. The instruction interleave rule is then enforced according to the adjusted priority value or values together with any base input processing priority values that have not been subject to adjustment.