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所以我正在开发一个程序，我使用 pthreads 来并行解决问题。现在，当我在函数中运行以下代码时出现段错误：average_power。

这是代码的相关部分，我很确定错误在某处：

struct args {
      signal *sigs;
      int filter_orders;
      double *filter_coeffss;
      signal *outputs;
      int threadIDs;
      int bandwidths;
      int bandNumbers;
};

double *band_power; 
pthread_t *tid;  // array of thread ids
int numThread;
int numProc;

void *worker(void *arg){
     struct args *currentArgs = (struct args*) arg;
     int i;
     int blocksize = currentArgs->bandNumbers / numThread; // note: floor

     int mystart, myend;
     int currentID = currentArgs->threadIDs;
     int band;
     int bandwidth = currentArgs->bandwidths;

     mystart = currentID*blocksize;
     if (currentID==(numThread-1)) { // last processor
         // the last processor will take care of the leftover
         // elements of the vector, in case num_threads doesn't
         // divide vector_len
         myend = currentArgs->bandNumbers;
     } else {
         myend = (currentID+1) * blocksize;
     }

     cpu_set_t set;
     CPU_ZERO(&set);
     CPU_SET(currentID%numProc,&set);
     if (sched_setaffinity(0,numProc,&set)<0) { // do it
              perror("Can't setaffinity");  // hopefully doesn't fail
              exit(-1);
     }

     //THIS LOOP WILL BE THE NEW WORKER PROCESS TO BE SPLIT UP VIA BANDS
     for (band=mystart;band<myend;band++) { 
     // Make the filter
         generate_band_pass(currentArgs->sigs->Fs, 
           band*bandwidth+0.0001, // keep within limits
           (band+1)*bandwidth-0.0001,
           currentArgs->filter_orders, 
           currentArgs->filter_coeffss);
         hamming_window(currentArgs->filter_orders,currentArgs->filter_coeffss);

    // Convolve
         convolve(currentArgs->sigs->num_samples,
            currentArgs->sigs->data,
            currentArgs->filter_orders,
            currentArgs->filter_coeffss,
            currentArgs->outputs->data);

    // Capture characteristics
         band_power[band] = avg_power(currentArgs->outputs->data,      currentArgs->outputs->num_samples);
     }

     pthread_exit(NULL); 
}

这就是工作函数以及从另一个函数的这一部分传递给它的结构参数，其中线程被初始化并给出指令：

band_power = (double *) malloc(sizeof(double)*numThread);
    tid = (pthread_t *) malloc(sizeof(pthread_t)*numThread);

    ///create all structs and initialize
    struct args *curargs;
    int p;
    int num_started;
    for(p=0;p<numThread;p++){
        outputNew = (struct signal *) malloc(sizeof(struct signal)); //THIS IS THE LINE THAT 

        outputNew = allocate_signal(sig->num_samples, sig->Fs, 0);
        curargs = (struct args *) malloc(sizeof(struct args));
        curargs->sigs = sig;
        curargs->filter_orders = filter_order;
        curargs->filter_coeffss = filter_coeffs;
        curargs->outputs = outputNew;
        curargs->threadIDs = p;
        curargs->bandwidths = bandwidth;
        curargs->bandNumbers = num_bands;
        rc=pthread_create( &(tid[p]), // thread id gets put here
               NULL,      // use default attributes
               worker,    // thread will begin in this function
               curargs  // we'll give it i as the argument
                 );
        if (rc==0) { 
            printf("Started thread %ld, tid %lu\n",p,tid[p]);
            num_started++;
        } else {
            printf("Failed to start thread %ld\n",p);
            perror("Failed to start thread");
            tid[p]=0xdeadbeef;
        }

因此，当在 *worker 结束时调用 average_power 时，我得到的错误是其中一个线程内的段错误（average_power 是正确的，我已经证明了这一点），或者当我取消注释以下行时出现错误我的初始化数组的循环。

outputNew = (struct signal *) malloc(sizeof(struct signal));

我想确保 outputNew 在放入 arg 结构之前有自己的空间，这样它就不会被覆盖，但是这一行使它无法编译。我这样做不正确吗？否则，average_power 从 args 结构访问此变量（输出），并且在发生这种情况时会出现段错误，我认为这意味着某处的某些内存未正确使用？对不起，如果这太长了，如果我说得不够好，我可以澄清任何部分。所有其他函数或对事物的调用都与我的项目有关，我知道这些是正确的，我的错误来自我的 pthread 实现并将数据传递到某个地方。

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1 回答 1

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我没有看到outputNew任何地方声明的变量。也许代替

outputNew = (struct signal *) malloc(sizeof(struct signal));

你的意思是：

struct signal *outputNew = malloc(sizeof(struct signal));
于 2013-06-06T00:19:56.823 回答