45 lines
853 B
Python
45 lines
853 B
Python
# test capability for threads to access a shared immutable data structure
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#
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# MIT license; Copyright (c) 2016 Damien P. George on behalf of Pycom Ltd
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import _thread
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def foo(i):
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pass
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def thread_entry(n, tup):
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for i in tup:
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foo(i)
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with lock:
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global n_finished
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n_finished += 1
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lock = _thread.allocate_lock()
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n_thread = 0
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n_thread_max = 2
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n_finished = 0
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# the shared data structure
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tup = (1, 2, 3, 4)
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# spawn threads
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for _ in range(n_thread_max):
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try:
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_thread.start_new_thread(thread_entry, (100, tup))
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n_thread += 1
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except OSError:
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# System cannot create a new thead, so stop trying to create them.
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break
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# also run the function on this main thread
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thread_entry(100, tup)
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n_thread += 1
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# busy wait for threads to finish
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while n_finished < n_thread:
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pass
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print(tup)
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