操作系统-jyy-5 多处理器编程

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       #include <pthread.h>

       int pthread_join(pthread_t thread, void **retval);

       Compile and link with -pthread.

       The pthread_join() function waits for the thread specified by
       thread to terminate.  If that thread has already terminated, then
       pthread_join() returns immediately.  The thread specified by
       thread must be joinable.

       If retval is not NULL, then pthread_join() copies the exit status
       of the target thread (i.e., the value that the target thread
       supplied to pthread_exit(3)) into the location pointed to by
       retval.  If the target thread was canceled, then PTHREAD_CANCELED
       is placed in the location pointed to by retval.

       If multiple threads simultaneously try to join with the same
       thread, the results are undefined.  If the thread calling
       pthread_join() is canceled, then the target thread will remain
       joinable (i.e., it will not be detached).

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#include "thread.h"
#define N 100000000
long sum = 0;
void Tsum() {
  for (int i = 0; i < N; i++) {
    //sum++;
    asm volatile(
        "incq %0" : "+m"(sum)
    );
  }
}
int main() {
  create(Tsum);
  create(Tsum);
  join();
  printf("sum = %ld\n", sum);
}

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def T_sum():
    for _ in range(3):
        t = heap.sum
        sys_sched()
        t = t + 1
        heap.sum = t
        sys_sched()
    heap.done += 1

def main():
    heap.sum = 0
    heap.done = 0
    sys_spawn(T_sum)
    sys_spawn(T_sum)
    sys_spawn(T_sum)
    while heap.done != 3:
        sys_sched()
    sys_write(f'sum = {heap.sum}\n')

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time uv run  ./mosaic.py -c ../sum-model/sum.py | uv run ./collect.py 
sum = 2⏎ 
sum = 3⏎ 
sum = 4⏎ 
sum = 5⏎ 
sum = 6⏎ 
sum = 7⏎ 
sum = 8⏎ 
sum = 9⏎ 
|V| = 92565, |E| = 333826.
There are 8 distinct outputs.
real    0m28.018s
user    0m27.243s
sys     0m0.796s

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time uv run  ./mosaic.py -c ../sum-model/sum.py | uv run ./collect.py 
sum = 10⏎ 
sum = 11⏎ 
sum = 12⏎ 
sum = 2⏎ 
sum = 3⏎ 
sum = 4⏎ 
sum = 5⏎ 
sum = 6⏎ 
sum = 7⏎ 
sum = 8⏎ 
sum = 9⏎ 
|V| = 489052, |E| = 1814000.
There are 11 distinct outputs.
real    2m51.901s
user    2m47.937s
sys     0m3.937s

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int x = 0, y = 0;

void T1() {
  x = 1;  // Store(x)
  printf("%d", y);  // Load(y)
}

void T2() {
  y = 1;  // Store(y)
  printf("%d", x); // Load(x)
}

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$ ./a.out | head -n 1000000 |sort |uniq -c
 902562 0 0 
  92944 0 1 
   4461 1 0 
     33 1 1