[SOLVED] CS /* Creates N threads, each of which sleeps a different, fixed

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File Name: CS_/*_Creates_N_threads,_each_of_which_sleeps_a_different,_fixed.zip
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/* Creates N threads, each of which sleeps a different, fixed
duration, M times.Records the wake-up order and verifies
that it is valid. */

#include
#include tests/threads/tests.h
#include threads/init.h
#include threads/malloc.h
#include threads/synch.h
#include threads/thread.h
#include devices/timer.h

static void test_sleep (int thread_cnt, int iterations);

void
test_alarm_single (void)
{
test_sleep (5, 1);
}

void
test_alarm_multiple (void)
{
test_sleep (5, 7);
}

/* Information about the test. */
struct sleep_test
{
int64_t start;/* Current time at start of test. */
int iterations; /* Number of iterations per thread. */

/* Output. */
struct lock output_lock;/* Lock protecting output buffer. */
int *output_pos;/* Current position in output buffer. */
};

/* Information about an individual thread in the test. */
struct sleep_thread
{
struct sleep_test *test; /* Info shared between all threads. */
int id; /* Sleeper ID. */
int duration; /* Number of ticks to sleep. */
int iterations; /* Iterations counted so far. */
};

static void sleeper (void *);

/* Runs THREAD_CNT threads thread sleep ITERATIONS times each. */
static void
test_sleep (int thread_cnt, int iterations)
{
struct sleep_test test;
struct sleep_thread *threads;
int *output, *op;
int product;
int i;

/* This test does not work with the MLFQS. */
ASSERT (!thread_mlfqs);

msg (Creating %d threads to sleep %d times each., thread_cnt, iterations);
msg (Thread 0 sleeps 10 ticks each time,);
msg (thread 1 sleeps 20 ticks each time, and so on.);
msg (If successful, product of iteration count and);
msg (sleep duration will appear in nondescending order.);

/* Allocate memory. */
threads = malloc (sizeof *threads * thread_cnt);
output = malloc (sizeof *output * iterations * thread_cnt * 2);
if (threads == NULL || output == NULL)
PANIC (couldnt allocate memory for test);

/* Initialize test. */
test.start = timer_ticks () + 100;
test.iterations = iterations;
lock_init (&test.output_lock);
test.output_pos = output;

/* Start threads. */
ASSERT (output != NULL);
for (i = 0; i < thread_cnt; i++){struct sleep_thread *t = threads + i;char name[16];t->test = &test
t->id = i;
t->duration = (i + 1) * 10;
t->iterations = 0;

snprintf (name, sizeof name, thread %d, i);
thread_create (name, PRI_DEFAULT, sleeper, t);
}

/* Wait long enough for all the threads to finish. */
timer_sleep (100 + thread_cnt * iterations * 10 + 100);

/* Acquire the output lock in case some rogue thread is still
running. */
lock_acquire (&test.output_lock);

/* Print completion order. */
product = 0;
for (op = output; op < test.output_pos; op++) {struct sleep_thread *t;int new_prod;ASSERT (*op >= 0 && *op < thread_cnt);t = threads + *op;new_prod = ++t->iterations * t->duration;

msg (thread %d: duration=%d, iteration=%d, product=%d,
t->id, t->duration, t->iterations, new_prod);

if (new_prod >= product)
product = new_prod;
else
fail (thread %d woke up out of order (%d > %d)!,
t->id, product, new_prod);
}

/* Verify that we had the proper number of wakeups. */
for (i = 0; i < thread_cnt; i++)if (threads[i].iterations != iterations)fail (“thread %d woke up %d times instead of %d”,i, threads[i].iterations, iterations);lock_release (&test.output_lock);free (output);free (threads);}/* Sleeper thread. */static voidsleeper (void *t_) {struct sleep_thread *t = t_;struct sleep_test *test = t->test;
int i;

for (i = 1; i <= test->iterations; i++)
{
int64_t sleep_until = test->start + i * t->duration;
timer_sleep (sleep_until timer_ticks ());
lock_acquire (&test->output_lock);
*test->output_pos++ = t->id;
lock_release (&test->output_lock);
}
}

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[SOLVED] CS /* Creates N threads, each of which sleeps a different, fixed
$25