60 lines
2.1 KiB
Plaintext
60 lines
2.1 KiB
Plaintext
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Title: Dining Philosophers
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Description:
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An implementation of a solution to the Dining Philosophers problem
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(a classic multi-thread synchronization problem). This particular
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implementation demonstrates the usage of nanokernel semaphores and
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timers from multiple (6) fibers.
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The philosopher always tries to get the lowest fork first (f1 then f2). When
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done, he will give back the forks in the reverse order (f2 then f1). If he
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gets two forks, he is EATING. Otherwise, he is THINKING. Transitional states
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are shown as well, such as STARVING when the philosopher is hungry but the
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forks are not available, and HOLDING ONE FORK when a philosopher is waiting
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for the second fork to be available.
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Each Philosopher will randomly alternate between the EATING and THINKING state.
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--------------------------------------------------------------------------------
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Building and Running Project:
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This nanokernel project outputs to the console. It can be built and executed
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on QEMU as follows:
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make qemu
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--------------------------------------------------------------------------------
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Troubleshooting:
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Problems caused by out-dated project information can be addressed by
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issuing one of the following commands then rebuilding the project:
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make clean # discard results of previous builds
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# but keep existing configuration info
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or
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make pristine # discard results of previous builds
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# and restore pre-defined configuration info
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--------------------------------------------------------------------------------
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Sample Output:
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Philosopher 0 [P: 3] HOLDING ONE FORK
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Philosopher 1 [P: 2] HOLDING ONE FORK
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Philosopher 2 [P: 1] EATING [ 1900 ms ]
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Philosopher 3 [P: 0] THINKING [ 2500 ms ]
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Philosopher 4 [C:-1] THINKING [ 2200 ms ]
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Philosopher 5 [C:-2] THINKING [ 1700 ms ]
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Demo Description
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----------------
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An implementation of a solution to the Dining Philosophers
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problem (a classic multi-thread synchronization problem).
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This particular implementation demonstrates the usage of multiple
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preemptible and cooperative threads of differing priorities, as
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well as dynamic mutexes and thread sleeping.
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