摘要:
A processor includes at least one instruction execution unit that executes store instructions to obtain store operations and a store queue coupled to the instruction execution unit. The store queue includes a queue entry in which the store queue gathers multiple store operations during a store gathering window to obtain a data portion of a write transaction directed to lower level memory. In addition, the store queue includes dispatch logic that varies a size of the store gathering window to optimize store performance for different store behaviors and workloads.
摘要:
A processor includes at least one instruction execution unit that executes store instructions to obtain store operations and a store queue coupled to the instruction execution unit. The store queue includes a queue entry in which the store queue gathers multiple store operations during a store gathering window to obtain a data portion of a write transaction directed to lower level memory. In addition, the store queue includes dispatch logic that varies a size of the store gathering window to optimize store performance for different store behaviors and workloads.
摘要:
A processor includes at least one instruction execution unit that executes store instructions to obtain store operations and a store queue coupled to the instruction execution unit. The store queue includes a queue entry in which the store queue gathers multiple store operations during a store gathering window to obtain a data portion of a write transaction directed to lower level memory. In addition, the store queue includes dispatch logic that varies a size of the store gathering window to optimize store performance for different store behaviors and workloads.
摘要:
A processor includes at least one instruction execution unit that executes store instructions to obtain store operations and a store queue coupled to the instruction execution unit. The store queue includes a queue entry in which the store queue gathers multiple store operations during a store gathering window to obtain a data portion of a write transaction directed to lower level memory. In addition, the store queue includes dispatch logic that varies a size of the store gathering window to optimize store performance for different store behaviors and workloads.
摘要:
A method and processor chip design for enabling a processor core to continue sending store operations speculatively to the store queue after the core receives indication that the store queue is full. The processor core is configured with speculative store logic that enables the processor core to continue issuing store operations while the store queue full signal is asserted. A copy of the speculatively issued store operation is placed within a speculative store buffer. The core waits for a signal from the store queue indicating the store operation was accepted into the store queue. When the speculatively-issued store operation is accepted within the store queue, the copy is discarded from the buffer. However, when the store operation is rejected, the speculative store logic re-issues the store operation ahead of normal store operations.
摘要:
A processor includes at least one instruction execution unit that executes store instructions to obtain store operations and a store queue coupled to the instruction execution unit. The store queue includes a queue entry in which the store queue gathers multiple store operations during a store gathering window to obtain a data portion of a write transaction directed to lower level memory. In addition, the store queue includes dispatch logic that varies a size of the store gathering window to optimize store performance for different store behaviors and workloads.
摘要:
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.
摘要:
A method, system, and processor chip design for reducing the latency between completing a LARX operation and receiving the associated STCX operation to complete the update to the cache line. Each entry of the store queue of the issuing processor is provided an additional tracking bit (priority bit). The priority bit is set whenever a STCX operation is placed within the entry. During selection of an entry for dispatch by the arbitration logic, the arbitration logic scans the value of the priority bits of each eligible entry. An entry with the priority bit set is given priority in the selection process within architectural rules. That entry is then selected for dispatch as early as is possible within the established rules.
摘要:
A method and processor system that substantially eliminates data bus operations when completing updates of an entire cache line with a full store queue entry. The store queue within a processor chip is designed with a series of AND gates connecting individual bits of the byte enable bits of a corresponding entry. The AND output is fed to the STQ controller and signals when the entry is full. When full entries are selected for dispatch to the RC machines, the RC machine is signaled that the entry updates the entire cache line. The RC machine obtains write permission to the line, and then the RC machine overwrites the entire cache line. Because the entire cache line is overwritten, the data of the cache line is not retrieved when the request for the cache line misses at the cache or when data goes state before write permission is obtained by the RC machine.
摘要:
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.