66 lines
2.6 KiB
Plaintext
66 lines
2.6 KiB
Plaintext
Title: Shared Floating Point Support
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Description:
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This test uses two tasks to independently compute pi, while two other tasks
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load and store floating point registers and check for corruption. This tests
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the ability of tasks to safely share floating point hardware resources, even
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when switching occurs preemptively. (Note that both sets of tests run
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concurrently even though they report their progress at different times.)
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The demonstration utilizes microkernel mutex APIs, timers, semaphores,
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round robin scheduling, and floating point support.
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Building and Running Project:
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This microkernel 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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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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Advanced:
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Depending upon the board's speed, the frequency of test output may range from
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every few seconds to every few minutes. The speed of the test can be controlled
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through the variable PI_NUM_ITERATIONS (default 700000). Lowering this value
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will increase the test's speed, but at the expense of the calculation's
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precision.
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make qemu PI_NUM_ITERATIONS=100000
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--------------------------------------------------------------------------------
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Sample Output:
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Floating point sharing tests started
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===================================================================
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Pi calculation OK after 50 (high) + 1 (low) tests (computed 3.141594)
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Load and store OK after 100 (high) + 29695 (low) tests
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Pi calculation OK after 150 (high) + 2 (low) tests (computed 3.141594)
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Load and store OK after 200 (high) + 47593 (low) tests
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Pi calculation OK after 250 (high) + 4 (low) tests (computed 3.141594)
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Load and store OK after 300 (high) + 66674 (low) tests
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Pi calculation OK after 350 (high) + 5 (low) tests (computed 3.141594)
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Load and store OK after 400 (high) + 83352 (low) tests
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Pi calculation OK after 450 (high) + 7 (low) tests (computed 3.141594)
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Load and store OK after 500 (high) + 92290 (low) tests
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===================================================================
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PROJECT EXECUTION SUCCESSFUL
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