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/*
dev/bitlock_test.c
project: bit array C library
url: https://github.com/noporpoise/BitArray/
maintainer: Isaac Turner <turner.isaac@gmail.com>
license: Public Domain, no warranty
date: Aug 2014
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>
#include <stdbool.h>
#include "bit_macros.h"
typedef struct {
pthread_t th;
size_t id, result;
} TestThread;
// Do a million loops
#define NUM_LOOPS 10000
char *locks, *data;
pthread_mutex_t *mutexes;
void* worker_bitlock(void *ptr)
{
TestThread *wrkr = (TestThread*)ptr;
size_t i;
for(i = 0; i < NUM_LOOPS; i++) {
bitlock_yield_acquire(locks, i);
wrkr->result += i + *(volatile char *)&data[i];
data[i] = wrkr->id;
usleep(5);
bitlock_release(locks, i);
usleep(5);
}
return NULL;
}
void* worker_bitlock_spin(void *ptr)
{
TestThread *wrkr = (TestThread*)ptr;
size_t i;
for(i = 0; i < NUM_LOOPS; i++) {
bitlock_acquire(locks, i);
wrkr->result += i + *(volatile char *)&data[i];
data[i] = wrkr->id;
usleep(5);
bitlock_release(locks, i);
usleep(5);
}
return NULL;
}
void* worker_mutex(void *ptr)
{
TestThread *wrkr = (TestThread*)ptr;
size_t i;
for(i = 0; i < NUM_LOOPS; i++) {
pthread_mutex_lock(&mutexes[0]);
wrkr->result += i + *(volatile char *)&data[i];
data[i] = wrkr->id;
usleep(5);
pthread_mutex_unlock(&mutexes[0]);
usleep(5);
}
return NULL;
}
void* worker_mutexes(void *ptr)
{
TestThread *wrkr = (TestThread*)ptr;
size_t i;
for(i = 0; i < NUM_LOOPS; i++) {
pthread_mutex_lock(&mutexes[i]);
wrkr->result += i + *(volatile char *)&data[i];
data[i] = wrkr->id;
usleep(5);
pthread_mutex_unlock(&mutexes[i]);
usleep(5);
}
return NULL;
}
// sum of 0 up to num (inclusive)
#define cumm_sum(num) ((num)*(((num)+1)/2)+(((num)&1) ? 0 : (num)/2))
int main(int argc, char **argv)
{
char *method = "Bitlocks";
void* (*func)(void*) = worker_bitlock;
if(argc == 2 && strcmp(argv[1],"bits") == 0) {}
else if(argc == 2 && strcmp(argv[1],"mutex") == 0) {
method = "Mutex";
func = worker_mutex;
}
else if(argc == 2 && strcmp(argv[1],"mutexes") == 0) {
method = "Mutexes";
func = worker_mutexes;
}
else if(argc == 2 && strcmp(argv[1],"spin") == 0) {
method = "Bitlocks-Spin";
func = worker_bitlock_spin;
}
else if(argc != 1) {
fprintf(stderr, "usage: ./bitlock_test <bits|mutex|spin>\n");
exit(-1);
}
printf("\nTesting %s\n\n", method);
int rc;
size_t i, num_threads = 30;
TestThread workers[num_threads];
locks = (char*)calloc(1, (NUM_LOOPS+7)/8);
data = (char*)calloc(1, NUM_LOOPS);
mutexes = (pthread_mutex_t*)calloc(NUM_LOOPS, sizeof(pthread_mutex_t));
for(i = 0; i < NUM_LOOPS; i++)
pthread_mutex_init(&mutexes[i], NULL);
// for(i = 0; i < num_threads; i++)
// printf("cummulative sum %zu: %zu\n", i, cumm_sum(i));
// Create threads
for(i = 0; i < num_threads; i++) {
workers[i] = (TestThread){.id = i+1, .result = 0};
rc = pthread_create(&workers[i].th, NULL, func, &workers[i]);
if(rc) { fprintf(stderr, "pthread error: %s\n", strerror(rc)); exit(-1); }
}
// Wait for threads to finish
for(i = 0; i < num_threads; i++) {
rc = pthread_join(workers[i].th, NULL);
if(rc) { fprintf(stderr, "pthread error: %s\n", strerror(rc)); exit(-1); }
}
for(i = 0; i < NUM_LOOPS; i++)
pthread_mutex_destroy(&mutexes[i]);
size_t sum = 0, expsum = 0;
for(i = 0; i < NUM_LOOPS; i++) sum += data[i];
for(i = 0; i < num_threads; i++) sum += workers[i].result;
// for(i = 0; i < num_threads; i++) printf("got: %zu %zu\n", i, workers[i].result);
// 0 1 2 3 4 5
// 0 1 3 6 10
expsum = cumm_sum(NUM_LOOPS-1)*num_threads + cumm_sum(num_threads)*NUM_LOOPS;
// expsum = cumm_sum(NUM_LOOPS-1) * num_threads;
bool pass = (sum == expsum);
for(i = 0; i < sizeof(locks) && locks[i] == 0; i++) {}
if(i < sizeof(locks)) {
printf("locks not zeroed!\n");
pass = false;
}
printf("sum: %zu exp: %zu\n", sum, expsum);
printf("%s.\n\n", pass ? "Pass" : "Fail");
free(mutexes);
free(data);
free(locks);
return pass ? EXIT_SUCCESS : EXIT_FAILURE;
}
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