Abstract: A wake-and-go mechanism is provided for a data processing system. When a thread is waiting for an event, rather than performing a series of get-and-compare sequences, the thread updates a wake-and-go array with a target address associated with the event. Software may save the state of the thread. The thread is then put to sleep. When the wake-and-go array snoops a kill at a given target address, logic associated with wake-and-go array may generate an exception, which may result in a switch to kernel mode, wherein the operating system performs some action before returning control to the originating process. In this case, the trap results in other software, such as the operating system or background sleeper thread, for example, to reload thread from thread state storage and to continue processing of the active threads on the processor.

Abstract: A clone set of General Purpose Registers (GPRs) is created to be used by a set of helper thread binaries, which is created from a set of main thread binaries. When the set of main thread binaries enters a wait state, the set of helper thread binaries uses the clone set of GPRs to continue using unused execution units within a processor core. The set of helper threads are thus able to warm up local cache memory with data that will be needed when execution of the set of main thread binaries resumes.

Abstract: A method of data processing in a processor includes maintaining a usage history indicating demand usage of prefetched data retrieved into cache memory. An amount of data to prefetch by a data prefetch request is selected based upon the usage history. The data prefetch request is transmitted to a memory hierarchy to prefetch the selected amount of data into cache memory.

Abstract: A mechanism is provided for managing a process-to-process communication request. A call is received in an operating system from an application in the data processing system. The operating system passes the call to a host fabric interface controller in the data processing system without processing the call. The host fabric interface controller processes the call using state information associated with the call. The call is processed by the host fabric interface controller without intervention by the operating system.

Abstract: A mechanism is provided for managing an application communication request. A first operating system passes a call from a first application in a first data processing system intended for a second application in a second data processing system to a first host fabric interface controller in the first data processing system without processing the call. The first host fabric interface processes the call using state information associated with the call to determine the second data processing system with which the call is associated. The first host fabric interface initiates a connection to a second host fabric interface in the second data processing system and transfers the call to a second operating system in the second data processing system via the connection to the second host fabric interface. The second data processing system then processes the call intended for the second application without assistance from the second application.

Abstract: A wake-and-go mechanism is provided for a data processing system. When a thread is waiting for an event, rather than performing a series of get-and-compare sequences, the thread updates a wake-and-go array with a target address associated with the event. The thread then goes to sleep until the event occurs. The wake-and-go array may be a content addressable memory (CAM). When a transaction appears on the symmetric multiprocessing (SMP) fabric that modifies the value at a target address in the CAM, the CAM returns a list of storage addresses at which the target address is stored. The operating system or a background sleeper thread associates these storage addresses with the threads waiting for an even at the target addresses, and may wake the one or more threads waiting for the event.

Abstract: A mechanism is provided for managing a process-to-process communication request. A call is received in an operating system from an application in the data processing system. The operating system passes the call to a host fabric interface controller in the data processing system without processing the call. The host fabric interface controller processes the call using state information associated with the call. The call is processed by the host fabric interface controller without intervention by the operating system.

Abstract: Mechanisms are provided for processing streaming data at high sustained data rates. These mechanisms receive a plurality of data elements over a plurality of non-sequential communication channels and write the plurality of data elements directly to the file system of the data processing system in an unassembled manner. The mechanisms determining whether to perform a data scrubbing operation or not based on history information indicative of whether data elements in the plurality of data elements are being received in a substantially sequential manner. The mechanisms perform a data scrubbing operation, in response to a determination to perform data scrubbing, to identify any missing data elements in the plurality of data elements written to the file system and assemble the plurality of data elements into a plurality of data streams in response to results of the data scrubbing indicating that there are no missing data elements.

Abstract: A mechanism is provided for managing a process-to-process communication request. A call is received in an operating system from an application in the data processing system. The operating system passes the call to a host fabric interface controller in the data processing system without processing the call. The host fabric interface controller processes the call using state information associated with the call. The call is processed by the host fabric interface controller without intervention by the operating system.

Abstract: A data processing system enables global shared memory (GSM) operations across multiple nodes with a distributed EA-to-RA mapping of physical memory. Each node has a host fabric interface (HFI), which includes HFI windows that are assigned to at most one locally-executing task of a parallel job. The tasks perform parallel job execution, but map only a portion of the effective addresses (EAs) of the global address space to the local, real memory of the task's respective node. The HFI window tags all outgoing GSM operations (of the local task) with the job ID, and embeds the target node and HFI window IDs of the node at which the EA is memory mapped. The HFI window also enables processing of received GSM operations with valid EAs that are homed to the local real memory of the receiving node, while preventing processing of other received operations without a valid EA-to-RA local mapping.

Abstract: A processor has an associated memory hierarchy including a cache memory. The processor includes an instruction sequencing unit that fetches instructions for processing, an operand data structure including a plurality of entries corresponding to operands of operations to be performed by the processor, and a computation engine. A first entry among the plurality of entries in the operand data structure specifies a first caching policy for a first operand, and a second entry specifies a second caching policy for a second operand. The computation engine computes and stores operands in the memory hierarchy in accordance with the cache policies indicated within the operand data structure.

Abstract: A hardware wake-and-go mechanism is provided for a data processing system. The wake-and-go mechanism looks ahead in the instruction stream of a thread for programming idioms that indicates that the thread is waiting for an event. The wake-and-go mechanism updates a wake-and-go array with a target address associated with the event for each recognized programming idiom. When the thread reaches a programming idiom, the thread goes to sleep until the event occurs. The wake-and-go array may be a content addressable memory (CAM). When a transaction appears on the symmetric multiprocessing (SMP) fabric that modifies the value at a target address in the CAM, the CAM returns a list of storage addresses at which the target address is stored. The wake-and-go mechanism associates these storage addresses with the threads waiting for an event at the target addresses, and may wake the one or more threads waiting for the event.

Abstract: A technique for performing cache injection includes monitoring an instruction stream for a specific instruction sequence. Addresses on a bus are then monitored, at a cache, in response to detecting the specific instruction sequence a determined number of times. Ownership of input/output data on the bus is then acquired by the cache when an address on the bus (that is associated with the input/output data) corresponds to an address of a data block stored in the cache.

Abstract: A technique for performing cache injection includes monitoring, at a cache, addresses on a bus. Ownership of input/output data on the bus is then acquired by the cache when an address on the bus (that is associated with the input/output data) corresponds to an address of a data block stored in the cache. A replacement policy position of the data block is then modified (to increase a probability that the data block is consumed prior to ejection from the cache).

Abstract: In response to receiving pre-processed code, a compiler identifies a code section that is not a candidate for acceleration and a code block that is a candidate for acceleration. The code block specifies an iterated operation having a first operand and a second operand, where each of multiple first operands and each of multiple second operands for the iterated operation has a defined addressing relationship. In response to the identifying, the compiler generates post-processed code containing lower level instruction(s) corresponding to the identified code section and creates and outputs an operand data structure separate from the post-processed code. The operand data structure specifies the defined addressing relationship for the multiple first operands and for the multiple second operands. The compiler places a block computation command in the post-processed code that invokes processing of the operand data structure to compute operand addresses.

Abstract: A wake-and-go mechanism is provided for a data processing system. The wake-and-go mechanism recognizes a programming idiom, specialized instruction, operating system call, or application programming interface call that indicates that a thread is waiting for an event. The wake-and-go mechanism updates a wake-and-go array with a target address, expected data value, and comparison type associated with the event. The thread then goes to sleep until the event occurs. The wake-and-go array may be a content addressable memory (CAM). When a transaction appears on the symmetric multiprocessing (SMP) fabric that modifies the value at a target address in the CAM, logic associated with the CAM performs a comparison based on the data value being written, expected data value, and comparison type.

Abstract: A method and a data processing system by which population count (popcount) operations are efficiently performed without incurring the latency and loss of critical processing cycles and bandwidth of real time processing. The method comprises: identifying data to be stored to memory for which a popcount may need to be determined; speculatively performing a popcount operation on the data as a background process of the processor while the data is being stored to memory; storing the data to a first memory location; and storing a value of the popcount generated by the popcount operation within a second memory location. The method further comprises: determining a size of data; determining a granular level at which the popcount operation on the data will be performed; and reserving a size of said second memory location that is sufficiently large to hold the value of the popcount.

Abstract: A mechanism is provided for managing a process-to-process intra-cluster communication request. A call from a first application is received in a first operating system in a first data processing system. The first operating system passes the call from the first operating system to a first host fabric interface controller in the first data processing system without processing the call. The first host fabric interface controller processes the call without intervention by the first operating system to determine a second data processing system in the plurality of data processing systems with which the call is associated. The first host fabric interface controller initiates an intra-cluster connection to a second host fabric interface controller in the second data processing system. The first host fabric interface controller then transfers the call to the second host fabric interface controller in the second data processing system via the intra-cluster connection.

Abstract: A set of helper thread binaries is created to retrieve data used by a set of main thread binaries. If executing a portion of the set of helper thread binaries results in the retrieval of data needed by the set of main thread binaries, then that retrieved data is utilized by the set of main thread binaries.

Abstract: A method performed in a data processing system initiates an asynchronous memory move (AMM) operation, whereby a processor performs a move of data in virtual address space from a first effective address to a second effective address and forwards parameters of the AMM operation to asynchronous memory mover logic for completion of the physical movement of data from a first memory location to a second memory location. The processor executes a second operation, which checks a status of the completion of the data move and returns a notification indicating the status. The notification indicates a status, which includes one of: data move in progress; data move totally done; data move partially done; data move cannot be performed; and occurrence of a translation look-aside buffer invalidate entry (TLBIE) operation. The processor initiates one or more actions in response to the notification received.