摘要:
One or more message signaled interruption requests from one or more input/output (I/O) adapters are converted to I/O adapter event notifications while retaining the message vector indication. An I/O adapter event notification may be routed and presented to a host or to a guest that the host is executing. To present the notification to the correct host or to the correct guest, various data structures in host and/or guest memory are used.
摘要:
One or more message signaled interruption requests from one or more input/output (I/O) adapters are converted to I/O adapter event notifications while retaining the message vector indication. An I/O adapter event notification may be routed and presented to a host or to a guest that the host is executing. To present the notification to the correct host or to the correct guest, various data structures in host and/or guest memory are used.
摘要:
One or more registers used to form an address usable in accessing storage are examined to determine if a zero address event has occurred in forming the address. In response to an indication that a zero address event has occurred in address formation, an alert is provided to the program using the address to access storage.
摘要:
Processing within a computing environment is facilitated using an extended DRAIN instruction. An extended DRAIN instruction is used to stall processing within a computing environment. The instruction includes an indication of the one or more processing stages at which processing is to be stalled. It also includes a control that allows processing to be stalled for additional cycles, as desired.
摘要:
An embodiment provides for operating an information processing system. An aspect of the invention includes allocating an execution interval to a first logical processor of a plurality of logical processors of the information processing system. The execution interval is allocated for use by the first logical processor in executing instructions on a physical processor of the information processing system. The first logical processor determines that a resource required for execution by the first logical processor is locked by another one of the other logical processors. An instruction is issued by the first logical processor to determine whether a lock-holding logical processor is currently running. The lock-holding logical processor waits to release the lock if it is currently running. A command is issued by the first logical processor to a super-privileged process for relinquishing the allocated execution interval by the first logical processor if the locking holding processor is not running.
摘要:
A method is provided for a first logical processor to determine a running status of a target logical processor of an information processing system. In such method, an instruction is issued by the first logical processor running on the information processing system for determining whether the target logical processor is running. In response to issuing the instruction, a state descriptor belonging to the target logical processor is queried to determine whether the target logical processor is currently running. A result is then returned to the first logical processor, the result indicating whether or not the target logical processor is currently running.
摘要:
A system, method and computer program product for steering a time-of-day (TOD) clock for a computer system having a physical clock providing a time base for executing operations that is stepped to a common oscillator. The method includes receiving, at a processing unit, a request to change a clock steering rate used to control a TOD-clock offset value for the processing unit, the TOD-clock offset defined as a function of a start time (s), a base offset (b), and a steering rate (r). The unit schedules a next episode start time with which to update the TOD-clock offset value. After updating TOD-clock offset value (d) at the scheduled time, TOD-clock offset value is added to a physical-clock value (Tr) value to obtain a logical TOD-clock value (Tb), where the logical TOD-clock value is adjustable without adjusting a stepping rate of the oscillator.
摘要:
Millicode store access checking instructions are provided via an operand access control register (OACR) including a test modifier indicator, which is communicatively coupled to an instruction unit subsystem, the instruction unit subsystem for fetching and decoding instructions. The instructions include a millicode instruction with an operand defining an address to check for a store access exception. In addition, an execution unit for executing the millicode instruction performs a method. The method includes receiving the millicode instruction from the instruction unit subsystem, testing for the store access exception at the address as if the test modifier is set absent an update to the OACR, and outputting a result of the testing for the store access exception.
摘要:
An extended DRAIN instruction is used to stall processing within a computing environment. The instruction includes an indication of the one or more processing stages at which processing is to be stalled. It also includes a control that allows processing to be stalled for additional cycles, as desired.
摘要:
Communication with adapters of a computing environment is facilitated. Instructions are provided that explicitly target the adapters. Information provided in an instruction is used to steer the instruction to an appropriate location within the adapter.