Orkuncakilkaya
7834b26ef8
Every pool thread runs the worker at once with the same states, so a mut state in a worker was a race nothing reported. check_worker_ref refuses a worker whose leading states include a mut one; threads.ludic's total moves into the words the worker is handed, under the mutex. The seeds are regenerated (ludic-dev reseed). ludic-dev test 305 passed, selfhost-test 33 passed. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
64 lines
2.5 KiB
Text
64 lines
2.5 KiB
Text
# threads.ludic — Job.parallel_for on real OS threads, with Sync.* made safe to share.
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# Each assertion that holds prints its number, so a full run prints:
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# 1 2 3 4 5 6 7
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# A worker is a top-level function taking (i: int, ctx: pointer-like) that computes on what ctx
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# points at; `fn name` passes it. Workers never touch the world or a list another thread can see.
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program Threads {
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const N: int = 20000
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state ThreadsState {
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calls: int = 0 # an atomic handle, made on the main thread before any work
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lock: int = 0 # a mutex handle
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}
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# out[i] = i * i: every index written exactly once, by whichever thread claimed it
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function square(i: int, out: words) -> void { out[i] = i * i }
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# count the call atomically, and add i to a shared total under the mutex. A worker may read a
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# state (the handles in it) but never change one - every thread runs it at once - so the total
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# lives in what the worker is handed
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function tally(threads_st: ThreadsState, i: int, total: words) -> void {
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Sync.add(threads_st.calls, 1)
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Sync.lock(threads_st.lock)
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total[0] = total[0] + i
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Sync.unlock(threads_st.lock)
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}
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# remember which calls ran on a pool thread - each with a little work in it, so on a busy machine
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# the calling thread cannot claim every index before a worker wakes
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function placed(i: int, out: words) -> void {
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var spin = 0
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for k in 0 .. 2000 { spin = spin + k % 7 }
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if Job.is_worker() { out[i] = 1 + spin * 0 } else { out[i] = spin * 0 }
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}
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entry (threads_st: mut ThreadsState) {
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if Sync.cpu_count() >= 1 { print(1) }
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if not Job.is_worker() { print(2) }
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let sq = words(N)
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Job.parallel_for(N, fn square, sq)
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var right = true
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for i in 0 .. N { if sq[i] != i * i { right = false } }
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if right { print(3) }
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threads_st.calls = Sync.atomic()
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threads_st.lock = Sync.mutex()
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let total = words(1)
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Job.parallel_for(N, fn tally, total)
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if Sync.get(threads_st.calls) == N { print(4) }
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let want = N * (N - 1) / 2
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if total[0] == want { print(5) }
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let ran = words(N)
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Job.parallel_for(N, fn placed, ran)
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var pooled = 0
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for i in 0 .. N { pooled += ran[i] }
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# with more than one core some calls ran on workers; with one, all ran here
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if (Sync.cpu_count() > 1 and pooled > 0) or (Sync.cpu_count() == 1 and pooled == 0) { print(6) }
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Job.parallel_for(0, fn square, sq) # nothing to do: returns at once
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let fn = 7 # `fn` is still an ordinary name, before `and` too
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if 0 < fn and fn < 8 { print(fn) }
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}
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}
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