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EP0142820A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Method of controlling multiprocessing system and hardware arrangement for accomplishing the method

Assignee: NEC Corp
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Filing: 1984-11-14
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Granted: —
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Expires: 2004-11-14
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Abstract

Abstract When a first program executed on a first processor of a plurality of processors of a multiprocessing system intends to lock a given shared resource of a main memory in orderto use same, if the desired resource is in use by a second program executed on a second processor, the first processor awaits an unlock signal which informs that one of the shared resources is released for use. The first processor responds to the unlock signal and checks whether or not the desired resource is available. If not available, the first program again awaits the reception of the unlock signal, while if available, the first program accesses the desired resource to use same.

Inventors

  • 👤 Shinji Nanba

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-23 10:18
CPC Classifications
G; G06; G06F; G06F9/00; G06F9/06; G06F9/46; G06F9/52; G06F15/00; G06F15/16; G06F15/163; G06F15/167; G06F9/30; G06F9/30003; G06F9/3004; G06F9/30076; G06F9/30087

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 185 words
A method of controlling a multiprocessing system wherein a plurality of programs are processed simultaneously by two or more processors which share in common a main memory, and wherein said processors lock a shared resource within said main memory by the steps of: (a) obtaining a right to use a common bus; (b) fetching the operand of the lock instruction; (c) determining whether the operand satisfies a first predetermined condition; (d) abandoning the right to use the common bus if the operand does not satisfy said first predetermined condition, and waiting until one of the processors produces an unlock signal; (e) repeating the steps (a) through (c) if the unlock signal is produced; (f) writing a first predetermined code into said operand if said operand satisfies said first predetermined condition; and (g) abandoning the right to use the common bus; and wherein said processors unlock the shared resource by the steps of: (h) obtaining the right to use the common bus; (i) writing a second predetermined code into said operand; (j) producing the unlock signal; and (k) abandoning the right to use the common bus.
Claim 2
Independent Claim 185 words
A method of controlling a multiprocessing system wherein a plurality of programs are processed simultaneously by two or more processors which share in common a main memory, and wherein said processors lock a shared resource within said main memory by the steps of: (a) obtaining a right to use a common bus; (b) fetching the operand of the lock instruction; (c) determining whether the operand satisfies a first predetermined condition; (d) abandoning the right to use the common bus if the operand does not satisfy said first predetermined condition, and waiting until one of the processors produces an unlock signal; (e) repeating the steps (a) through (c) if the unlock signal is produced; (f) writing a first predetermined code into said operand if said operand satisfies said first predetermined condition; and (g) abandoning the right to use the common bus; and wherein said processors unlock the shared resource by the steps of: (h) obtaining the right to use the common bus; (i) writing a second predetermined code into said operand; (j) producing the unlock signal; and (k) abandoning the right to use the common bus.
Claim 3
Dependent Claim 104 words
A hardware arrangement for controlling a multiprocessing system wherein a plurality of programs are processed simultaneously by two or more processors which share in common a main memory, and wherein said processors lock a shared resource within said main memory, said hardware arrangement comprising: a means for performing a logical add, said means having a plurality of input terminals coupled to an output terminal of each of the processors and having an output terminal coupled to an input terminal of each of the processors, said means gate being supplied with an unlock signal which one of the processors produces when unlocking the shared resource.
Claim 4
Dependent Claim 104 words
A hardware arrangement for controlling a multiprocessing system wherein a plurality of programs are processed simultaneously by two or more processors which share in common a main memory, and wherein said processors lock a shared resource within said main memory, said hardware arrangement comprising: a means for performing a logical add, said means having a plurality of input terminals coupled to an output terminal of each of the processors and having an output terminal coupled to an input terminal of each of the processors, said means gate being supplied with an unlock signal which one of the processors produces when unlocking the shared resource.

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