Question

我需要2个线程： TC 和 TS ，这样它们由两个主要部分组成，每个部分访问共享数据，并且必须同步线程。同步应该是这样的： synchronization

红色代码正在使用共享数据U，但get U可以放在TS主题上的虚线矩形之前。 Xcurrent可以位于TC或TS个任务中，但是send Ucurrent的共享硬件和get必须在send之后结束了。

出现死锁，我无法找到优雅的解决方案。线程TS：

#include <stdio.h>        /* printf, scanf, NULL */
#include <stdlib.h>     /* malloc, free, rand */

#define _USE_MATH_DEFINES
#include <math.h>
#include <windows.h>

#include <pthread.h>
#include <time.h>

// CRLT-C var
static int stop = 0;

// TIMEING vars
__int64 frequencyT, startT, endT = 0;
double baseAngleLast;
double pendulAngleLast;

// THREADING vars
bool startedS = false, Usent = false;
double * Ucmd;
pthread_mutex_t mutexU = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t mutexBoard = PTHREAD_MUTEX_INITIALIZER;
unsigned int Ulenght = 6;
pthread_cond_t signal_to_read_state = PTHREAD_COND_INITIALIZER;
pthread_cond_t signal_to_read_cmd = PTHREAD_COND_INITIALIZER;
DWORD sleepTime = 30; // in milliseconds
int currentState = 3;


void *sendingCMD(void * )
{
  double * U_tmp;
  U_tmp = (double*)malloc(sizeof(double)*Ulenght);

  startedS = true;
  printf("Sin\n");

  while (stop == 0)
  {
      printf("Smu-\n");
      //get U
      pthread_mutex_lock( &mutexU );  
      printf("Smu..\n");
      pthread_cond_wait(&signal_to_read_cmd, &mutexU);
      memcpy(U_tmp,Ucmd,sizeof(double)*Ulenght);
      pthread_mutex_unlock( &mutexU );
      printf("Smu+\n");

      pthread_mutex_lock( &mutexBoard );
      for (unsigned int i = 0; i<Ulenght; i++)
      {   
          //send CMD signal           
          printf("%f ", U_tmp[i]);            
          if (i == Ulenght -1) printf("\n");
      }
          Sleep(sleepTime);           // miliseconds 
      currentState = currentState + 1;
      pthread_cond_signal(&signal_to_read_state);
      pthread_mutex_unlock( &mutexBoard );
      printf("Smb\n");
  }
  printf("Task S terminated. \n");
  return (NULL);
}


void *computingU(void *)
{
  double * U_tmp;
  U_tmp = (double*)malloc(sizeof(double)*Ulenght);
  int currentStateTMP =0;
  bool fisrtLoop = true;  

  printf("Uin\n");

  while (stop == 0)
  {       
      printf("Umb- \n");
      // get  current state       
      pthread_mutex_lock( &mutexBoard );      
      if (!fisrtLoop) 
      {
          printf("UmbFalse \n");
          pthread_cond_wait(&signal_to_read_state, &mutexBoard);
      }
      else
      {       
          printf("UmbTrue \n");
          fisrtLoop=false;
      }
      currentStateTMP =currentState;      
      pthread_mutex_unlock( &mutexBoard );

      printf("Umb+ \n");

      pthread_mutex_lock( &mutexU );      

      for (unsigned int i=0;i<Ulenght;i++)
      {       
          Ucmd[i] = Ucmd[i]+ (double)currentStateTMP/i;
      }       
      pthread_cond_signal(&signal_to_read_cmd);
      pthread_mutex_unlock( &mutexU );    
      printf("Umu\n");
  }
  return (NULL);
}


void signal_handler(int signal)
{
  stop = 1;
}


int main(int argc, char* argv[])
{
      //initializing output buffer to 0[V]
      Ucmd= (double*)malloc(sizeof(double)*Ulenght);
      for (unsigned int i=0;i<Ulenght;i++) 
          Ucmd[i] = 0;

  //init threads 
      int rc1, rc2;   

      pthread_t threadU, threadS;
      /* Create independent threads each of which will execute functionC */
      if( (rc1=pthread_create( &threadU, NULL, &computingU, NULL)) )   {
          printf("ThreadU creation failed: %d\n", rc1);
      }

      if( (rc2=pthread_create( &threadS, NULL, &sendingCMD, NULL)) )
      {
          printf("ThreadS creation failed: %d\n", rc2);
      }

      while (stop == 0);
      printf("Main terminated, closing board in 10ms. \n");
      Sleep(10);


  return 0;
}

阻止出现在： pthread_cond_wait(&signal_to_read_state, &mutexBoard);处的 TC TS pthread_cond_wait(&signal_to_read_cmd, &mutexU);

顺便说一下，如果我从VS2010复制粘贴，为什么剂量无法识别stackoverflow我粘贴的代码段？

死锁pthread C ++与信令

0 个答案: