Lab 3.3 complete

Labs/Lab3/Makefile

@@ -17,6 +17,10 @@ mytime: mytime.c
 summation: summation.c
 	$(CC) $(CFLAGS) -o $@ $< $(LFLAGS) 
 
+summation3: summation3.c
+	$(CC) $(CFLAGS) -o $@ $< $(LFLAGS) 
+test: test.c
+	$(CC) $(CFLAGS) -o $@ $< $(LFLAGS) 
 
 .PHONY: clean
 clean:

Labs/Lab3/summation3.c

+/*
+ * Copyright (c) 2012 Bucknell University
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: L. Felipe Perrone (perrone@bucknell.edu)
+ */
+
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <sys/time.h>
+// structure for thread arguments
+struct thread_args {
+	int tid;
+	int a;
+	int b;
+	double x;
+	double result;
+};
+
+int shared;
+
+//function that each thread will execute
+void *SumExp(void *args_ptr) {
+	int i;
+	//define the argument structure 
+	struct thread_args *myargs_ptr = (struct thread_args*) args_ptr;
+	myargs_ptr->result = 0;
+
+	shared = 123;
+
+	printf("Thread %d starting a= %d, b= %d, x= %lf\n",
+			myargs_ptr->tid,
+			myargs_ptr->a,
+			myargs_ptr->b,
+			myargs_ptr->x);
+	//if (myargs_ptr ->tid == 3){printf("thread 3 exits\n");exit(0);}
+	//if (myargs_ptr->tid == 3){printf("thread 3 runs execl\n"); execl("/bin/ls","ls",NULL);}
+	for (i=myargs_ptr->a; i<myargs_ptr->b; i++) {
+		myargs_ptr->result += pow(i, myargs_ptr->x);
+		
+	}
+
+	printf("Thread %d done a= %d, b= %d, x= %lf -> result = %lf\n",
+			myargs_ptr->tid,
+			myargs_ptr->a,
+			myargs_ptr->b,
+			myargs_ptr->x,
+			myargs_ptr->result);
+
+	pthread_exit((void*) args_ptr);
+}
+
+
+int main (int argc, char *argv[]) {
+
+	pthread_attr_t attr;
+
+	struct thread_args *targs; // array for thread argument structs
+	struct thread_args **tstatus; // array of pointers to returns from threads
+	pthread_t *tidp; // array for thread ids
+	
+	//initiated the time_value struct
+	struct timeval tvS, tvE;
+	
+	//get the time when this program starts
+	gettimeofday(&tvS, NULL);
+
+	int ret_val;
+	int i;
+	void *status;
+	double summation = 0;
+
+	int num_threads, increment; // command line parameters
+
+	if (argc < 3) {
+		printf("usage: summation [numthreads] [increment]\n");
+		exit(-1);
+	}
+
+	num_threads = atoi(argv[1]);
+	increment = atoi(argv[2]);
+	printf("numth is: %d, increment is: %d\n", num_threads, increment);
+	targs = (struct thread_args *) calloc(num_threads, sizeof(struct thread_args));
+	tstatus = (struct thread_args **) calloc(num_threads, sizeof(struct thread_args *));
+	tidp = (pthread_t *) calloc(num_threads, sizeof(pthread_t));//to have an array to store all the tids
+
+	// initialize attr variable
+	pthread_attr_init(&attr);
+
+	// initialize thread detached state to joinable
+	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
+
+	for (i=0; i<num_threads; i++) {
+		tstatus[i] = malloc(sizeof(struct thread_args));
+
+		targs[i].a = increment*i;
+		targs[i].b = increment*(i+1);
+		targs[i].x = 2;
+		targs[i].tid = i;
+		targs[i].result = 0;
+		
+		ret_val = pthread_create(&tidp[i], &attr, SumExp, (void *) &targs[i]);
+		if (ret_val) {
+			printf("ERROR in pthread_create for thread %d: return value= %d\n", 
+					i, ret_val);
+			exit(-1);
+		}
+	}
+
+	// free attribute variable
+	pthread_attr_destroy(&attr);
+
+	// main thread waits for spawned threads to terminate
+	for(i=0; i<num_threads; i++) {
+		// 
+		ret_val = pthread_join(tidp[i], (void **) &tstatus[i]);
+		if (ret_val) {
+			printf("ERROR in pthread_join() for thread %d = return value= %d\n",
+					i, ret_val);
+			exit(-1);
+		}
+
+		summation += tstatus[i]->result;
+		printf("Joined thread %d; returned= %lf\n", i, tstatus[i]->result);
+	}
+
+	printf("Total value computed = %lf\n", summation);
+	//get the time when this program ends
+	gettimeofday(&tvE, NULL);
+	
+	//get the difference bt two times
+	long interval = tvE.tv_sec - tvS.tv_sec;
+	long intervalMicro = tvE.tv_usec - tvS.tv_usec;
+	printf("The time of this program in sec: %ld, in micro sec: %ld \n", interval, intervalMicro);
+
+	pthread_exit(NULL);
+	printf("still here\n");
+}