Patent ID: 6108693
Filing Date: 2000-08-22
Classification: G06F

Abstract:
A data communication system in a multiprocessor system having a plurality of processors and a storage device that includes a shared memory, which is shared by the plurality of processors, and a local memory provided for each processor, and communicating between said processors, wherein(1) a processor on a transmitting side includes:(1a) communication buffer selecting means for selecting one of two communication buffers of the shared memory in accordance with a given rule;(1b) write inhibit means for changing the selected communication buffer to a write-disabled state in order to inhibit writing of the selected communication buffer by other processors;(1c) data writing means for copying data from the local memory that corresponds to this processor to the selected communication buffer;(1d) write-completion notifying means for notifying a receiving processor of completion of writing; and(1e) transmission-end discriminating means for discriminating end of transmission processing by judging whether all data to be transmitted has been written to the communication buffer; and(2) a processor on a receiving side includes:(2a) communication buffer selecting means for selecting one of said two communication buffers of the shared memory by a rule corresponding to that of said communication buffer selecting means of the processor on the transmitting side;(2b) read wait means for causing waiting until the selected communication buffer attains a read-enabled state;(2c) data reading means for copying data from the selected communication buffer to the local memory that corresponds to this processor;(2d) read completion notifying means for changing said communication buffer to a write-enabled state after data is read in; and(2e) means for discriminating end of reception processing.