Question

由于我在GPU中拥有大量的malloc数据，我必须拆分它。就像下面一样，将temp1和temp2从开始到结束分开一次：

for (int start = 0; start < total; start += step) {
    int end = start + step > total?total:start+step;
    fprintf(stderr, "total %ld start :%ld end :%ld\n", total, start, end);

    #pragma acc data pcopyin(sum[0:n_sample], num[0:n_sample*total], lognn[0:preFact])
    #pragma acc data copy(temp1[start*n_array1:end*n_array1], temp2[start*n_array2:end*n_array2])
    #pragma acc kernels loop independent
    for (int index = start; index < end; ++index) {
                unsigned long long * t1 = temp1 + index * n_array1;
                unsigned long long * t2 = temp2 + index * n_array2;
               // fprintf(stderr, "use %d\t", index*n_array1);
                int k = count / 32;
                int l = count / 64;
                t1[k] <<= 2;
                t2[l] <<= 1;
                int x = num[index * n_sample + i];
                int y = num[index * n_sample + j];
     }
}

但是当第一个循环完成并且开始运行第二个循环时，我总是被告知分段错误。索引var应该是[0：end-start]吗？或者在循环完成时应该进行一些同步？

谢谢！

Answer 1

数据子句不是[0：end-start]。下限和上限可以是表达式。但是你必须确保lower_bound＆lt; UPPER_BOUND

openacc在分割大数据时说分段错误

1 个答案: