I am getting glibc detected at second malloc usage? Is there any specific reason?Code:/* *Sieve of Eratosthenes * * Programmed by Michael J. Quinn * * Last modification: 7 September 2001 */ #include "mpi.h" #include <stdio.h> #include <stdlib.h> #include <math.h> #define MIN(a,b) ((a)<(b)?(a):(b)) int main(int argc, char *argv[]) { int count; /* Local prime count */ double elapsed_time; /* Parallel execution time */ int first; /* Index of first multiple */ int global_count; /* Global prime count */ int high_value; /* Highest value on this proc */ int i; int id; /* Process ID number */ int index; /* Index of current prime */ int low_value; /* Lowest value on this proc */ char *marked; /* Portion of 2,...,'n' */ int n=(double)atoi(argv[1]); /* Sieving from 2, ..., 'n' */ int p; /* Number of processes */ int proc0_size; /* Size of proc 0's subarray */ int prime; /* Current prime */ int size; /* Elements in 'marked' */ char initMarked[(int)sqrt(n)]; int sqn; int nop=1; int *primes; sqn = sqrt((double)atoi(argv[1])); if(sqn%2==0) sqn = sqn/2; else sqn = sqn/2+1; for (i = 0; i < sqn; i++) initMarked[i] = 0; prime = 2; low_value = 2; index = 0; nop = 1; do { if ((2*prime-1) * (2*prime-1) > (2*low_value-1)) first = ((2*prime-1) * (2*prime-1) - (2*low_value-1))/2; else { if (!((2*low_value-1) % (2*prime-1))) first = 0; else{ first = (2*prime-1) - ((2*low_value-1) % (2*prime-1)); first = (first%2==0)?first/2:(first+2*prime-1)/2; } } for (i = first; i < sqn; i +=2*prime-1){ initMarked[i] = 1;} while (initMarked[++index]); prime = index + 2; nop++; } while ((2*prime-1) * (2*prime-1) <=n ); primes=(int*) malloc (size*sizeof(int));; index = 0; for(i=0;i<sqn;i++){ if(!initMarked[i]){ primes[index]=2*i+3; index++; } } //MPI_Bcast(&primes,nop,MPI_INT,0,MPI_COMM_WORLD); printf("%d\n",nop); //MPI_Init(&argc,&argv); int rc = MPI_Init(&argc,&argv); if (rc != MPI_SUCCESS) { printf ("Error starting MPI program. Terminating.\n"); MPI_Abort(MPI_COMM_WORLD, rc); } MPI_Barrier(MPI_COMM_WORLD); MPI_Comm_rank(MPI_COMM_WORLD,&id); MPI_Comm_size(MPI_COMM_WORLD,&p); elapsed_time = -MPI_Wtime(); /* Start the timer */ if (argc != 2) { if (!id) printf("Command line: %s <m>\n", argv[0]); MPI_Finalize(); exit(1); } n = atoi(argv[1]); if(n%2==0) n=n/2; else n=n/2+1; /* Figure out this process's share of the array, as well as the integers represented by the first and last array elements */ low_value = 2 + (id)*(n-1)/p; high_value = 1 + (id+1)*(n-1)/p; size = high_value - low_value + 1; /* Bail out if all the primes used for sieving are not all held by process 0 */ proc0_size = (n-1)/p; if (2*(2 + proc0_size) < (int) sqrt((double) ((2.0)*n))) { if (!id) printf("Too many processes\n"); MPI_Finalize(); exit(1); } /* Allocate this process's share of the array. */ marked = (char*) malloc (size*sizeof(char)); if (marked == NULL) { printf ("Cannot allocate enough memory\n"); MPI_Finalize(); exit(1); } for (i = 0; i < size; i++) marked[i] = 0; index = 0; do { prime = primes[index++]; //printf("prime = %d id = %d\n",prime,id); if (prime * prime > (2*low_value-1)) first = (prime* prime - low_value)/2; else { if (!((2*low_value-1) % prime)) first = 0; else{ first = prime - ((2*low_value-1) % prime); first = ((first%2==0)?first/2:(first+prime)/2); } } for (i = first; i < size; i += prime) marked[i] = 1; } while (index < nop); count = 0; for (i = 0; i < size; i++) if (!marked[i]) count++; MPI_Reduce(&count, &global_count, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD); /* Stop the timer */ elapsed_time += MPI_Wtime(); /* Print the results */ if (!id) { printf("There are %d primes less than or equal to %d\n", global_count, n); printf("SIEVE (%d) %10.6f\n", p, elapsed_time); } MPI_Finalize(); return 0; }
Originally Posted by tabstop
