Fujitsu Corporation

Makoto Hataida

Takashi Yamamoto

Toshikazu Ueki

Takaharu Ishizuka

Yuka Hosokawa

Daisuke Itou

Takeshi Owaki

Takayuki Kinoshita

Seishi Okada

Hidekazu Osano

Toshiyuki Muta

Yoshikazu Iwami

Takao Matsui

Akira Okamoto

Manabu Nakao

Atsushi Morosawa

Seiji Satta

Jin Takahashi

Daisuke Itoh

Norihiko Fukuzumi

Atsushi Morozawa

A node includes: an arithmetic processing device; and a first memory, wherein the arithmetic processing device includes: a processor core; a storing circuit to store a first failure node list in which first information indicating that a failure has occurred or second information indicating that no failure has occurred is set for each of nodes; a request issuing circuit to issue a first request to a second memory provided at a first node among the nodes; a setting circuit to set the first information for the first node in the first failure node list when the first request has timed out; and an issuance inhibition circuit to inhibit, based on a second request to the second memory from the processor core, the second request from being issued by the request issuing circuit when the first information is set for the first node in the first failure node list.

Node, arithmetic processing device, and arithmetic processing method

An error check apparatus including, a packet protocol error check processing circuit configure to detect a protocol error of a packet, a retry control circuit configured to receive the protocol error of the packet from the packet protocol error check processing circuit, and to perform request for retry for data of the packet if the received protocol error has not been detected from a packet retransmitted by retry request, and an error notification circuit configured to notify of the protocol error of the packet to a processing unit in a higher-level layer if the protocol error is not a first protocol error for the packet.

Apparatus and method for error check of transmission data

An arbitration method includes a first process to perform a path control to transfer data from physically plural input ports logically having plural virtual channels to an arbitrary one of the plural output ports, wherein only one channel is selectable at one input port at an arbitrary point in time, by performing an arbitration among the channels of each of the plural input ports according to an arbitrary arbitration algorithm other than a time-division algorithm, and a second process to perform an arbitration among the plural input ports according to the arbitrary arbitration algorithm. The arbitrary arbitration algorithm used in the first and second processes is switched to the time-division algorithm for a predetermined time in response to a trigger.

Arbitration method, arbiter circuit, and apparatus provided with arbiter circuit

Each chip arranged in each crossbar switch creates and issues, if a packet is input, a log collection packet for collecting a log of the packet. Each chip collects a log related to a transfer of the input packet. Each chip embeds, in the issued log collection packet or a log collection packet transferred from a crossbar switch in a previous stage, the collected log. If a transfer destination of the packet is other than the crossbar switches, each chip stores, in a storage space, the log embedded in the log collection packet and then transfers, to the transfer destination, only an original packet in which the log is deleted. In contrast, if the transfer destination is a crossbar switch, each chip transfers the log collection packet to a crossbar switch in a next stage.

Crossbar switch system

To prevent a decrease in performance of controlling a snoop tag. A queue is stored with REPLACE target WAY information and an index as an entry associated with a REPLACE request received from a processor, the index stored in the queue is compared with an index of a subsequent READ request, and, as a result of the comparison, a process based on the index-coincident READ request is executed with respect to the snoop tag corresponding to a content of a cache memory of the processor. Further, the REPLACE target WAY information of the READ request is replaced with the WAY information in the index-coincident entry within the queue.

Control device for snoop tag

In an information processing apparatus that includes a first and second semiconductor devices that are connected to each other and also includes a system control device that is connected to the first and second semiconductor devices, the timers that are mounted on the semiconductor devices are all synchronized by successively performing a timer correction process between a semiconductor device in which the timer is synchronized and a semiconductor device, adjacent to the semiconductor device, in which the timer is not synchronized, and, when an error occurs in the information processing device, the value in the synchronized timer and the error information are stored in a predetermined register.

Time correction in a semiconductor device using correction information provided by an adjacent semiconductor device

An information processing apparatus includes a node, and a system controlling apparatus connected to the node. The node includes a first detecting unit that detects first error information, a second detecting unit that detects second error information, a retaining unit that retains the first and the second error information, and a temporary retaining unit that retains new first error information and new second error information, and when the first or second error information is initialized, causes the retaining unit to store error information corresponding to the initialized first or second error information. The system controlling apparatus includes a controlling unit connected to the retaining unit, and a firmware that causes the controlling unit to read into the first and second error information and to initialize the new first or second error information.

Information processing apparatus and information processing method

An arbitration device including: a first measuring circuit to measure a first period; a second measuring circuit to measure a second period; a second selection circuit to select and output the first period or the second period according to a first selection signal; a first control circuit to output the first selection signal according to the first period and the second period; a third selection circuit to select a third data or either the first data or the second data according to a second selection signal; a third measuring circuit to measure a third period; a fourth measuring circuit to measure a fourth period; and a second control circuit to output the second selection signal according to either the selected first period or the selected second period and the third period and the fourth period.

Arbitration device that arbitrates conflicts caused in data transfers

A northbridge, when detecting a synchronization break of a redundant CPU, stops the operation of an abnormal CPU bus where an error has occurred and the firmware in a firmware hub instructs the northbridge to inhibit an external instruction. In addition, the firmware saves the inside information of a normal CPU connected to a normal CPU bus and cache data on a memory and the northbridge issues reset to all CPUs in the home system board. The firmware then restores the inside information of the CPU saved on the memory to all CPUs and instructs the northbridge to cancel the inhibition of the external instruction.

Information processing apparatus for inhibiting instructions, saving and restoring internal information in response to abnormality in redundant processor system

A request issued by the CPU is output from the local arbiter by way of the CPU bus and the CPU-issued request queue. The cache replacement request loop-back circuit determines at the loop-back determination circuit whether the outputted request is a cache replacement request or not. A request other than a cache replacement request is output onto the local bus. A cache replacement request is output to the selector and sent to the request handling section when there is no valid request on the global bus.

Multiprocessor system, system board, and cache replacement request handling method

An information processing device having two processing units capable of operating in synchronization with each other, includes: a common unit capable of outputting an identical signal to the two processing units; detection units that are respectively provided for the processing units and each detects errors occurred in corresponding processing unit respectively; a comparison unit that compares outputs from the two processing units; and a control unit that controls signals from the processing units to the common unit, based on a detection result of the detection units and a comparison result of the comparison unit, and determines, if errors of an identical type are simultaneously detected by the detection units, that the errors are due to an error of the common unit.

Information processing device and error processing method

A control device managing a plurality of nodes transmitting and receiving data containing an error correcting code, comprises means accepting, when any one of the nodes detects an uncorrectable error from the data containing the error correcting code, a signal transmitted by the node detecting the error, means judging from a record of the detection of a first node, when accepting the signal from a second node receiving data transmitted by the first node, whether or not the first node has detected the uncorrectable error from the data transmitted to the second node, and means stopping, when the first node has detected the uncorrectable error from the data transmitted to the second node, a process attributed to the acceptance of the signal from the second node.

Node device, control device, control method and control program

In a system controller including a CPU-issued request queue having a circuit that processes plural requests having identical addresses not to be inputted to the CPU-issued request queue, a latest request other than a cache replace request is retained by an input-request retaining section. Consequently, even if an address of an issued request for cache replace request matches an address of a request retained by the CPU-issued request queue, the issued request for the cache replace request is not retried but is queued in the CPU-issued request queue when the address of the issued request for the cache replace request does not match the entire address retained by the input-request retaining section.

System controller, identical-address-request-queuing preventing method, and information processing apparatus having identical-address-request-queuing preventing function

In an information processing system loaded with a CPU having cache and a system controller having a copy of a tag of the cache (snoop tag), and the CPU not issuing replacement information about the cache tag, the number of WAYs of the snoop tags in the system controller is larger than the number of WAYs of the cache tags in the CPU to reduce a cache miss rate and suppress the degradation of performance by suppressing excess replacement of the cache tags in the CPU.

Information processing system, information processing board, and method of updating cache tag and snoop tag

A cache-status maintaining unit stores address information of data stored in each entry of a cache memory, and maintains a status of each entry as any one of 'strongly modified', 'weakly modified', &#x201c;shared&#x201d;, and &#x201c;Invalid&#x201d;. A data-fetching-procedure selecting unit selects, upon receiving a data read request, at least one data fetching procedure based on the address information and the status. A read-data delivering unit selects latest data from among the data fetched, and delivers the latest data to a processor that issued the data read request. A cache-status updating unit updates, when registering the address information of the data, updates the status of the entry based on a type of the data read request.

Growing community of inventors

Kawasaki, Japan

Makoto Hataida