| 1 | // This file deliberately uses low level linux-specific API for thread creation because: |
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| 2 | // - instruction-stepping over thread creation using higher-level functions was very slow |
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| 3 | // - it was also unreliable due to single-stepping bugs unrelated to this test |
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| 4 | // - some threading libraries do not create or destroy threads when we would expect them to |
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| 5 | |
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| 6 | #include <sched.h> |
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| 7 | |
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| 8 | #include <atomic> |
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| 9 | #include <cstdio> |
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| 10 | |
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| 11 | enum { STACK_SIZE = 0x2000 }; |
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| 12 | |
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| 13 | static uint8_t child_stack[STACK_SIZE]; |
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| 14 | |
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| 15 | pid_t child_tid; |
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| 16 | |
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| 17 | std::atomic<bool> flag(false); |
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| 18 | |
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| 19 | int thread_main(void *) |
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| 20 | { |
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| 21 | while (! flag) // Make sure the thread does not exit prematurely |
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| 22 | ; |
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| 23 | |
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| 24 | return 0; |
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| 25 | } |
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| 26 | |
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| 27 | int main () |
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| 28 | { |
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| 29 | int ret = clone(fn: thread_main, |
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| 30 | child_stack: child_stack + STACK_SIZE/2, // Don't care whether the stack grows up or down, |
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| 31 | // just point to the middle |
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| 32 | CLONE_CHILD_CLEARTID | CLONE_FILES | CLONE_FS | CLONE_PARENT_SETTID | |
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| 33 | CLONE_SIGHAND | CLONE_SYSVSEM | CLONE_THREAD | CLONE_VM, |
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| 34 | arg: nullptr, // thread_main argument |
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| 35 | &child_tid); |
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| 36 | |
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| 37 | if (ret == -1) |
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| 38 | { |
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| 39 | perror(s: "clone" ); |
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| 40 | return 1; |
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| 41 | } |
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| 42 | |
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| 43 | flag = true; |
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| 44 | |
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| 45 | return 0; |
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| 46 | } |
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| 47 | |
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