/* Checks that recent_cpu and priorities are updated for blocked
threads.
The main thread sleeps for 25 seconds, spins for 5 seconds,
then releases a lock. The “block” thread spins for 20 seconds
then attempts to acquire the lock, which will block for 10
seconds (until the main thread releases it). If recent_cpu
decays properly while the “block” thread sleeps, then the
block thread should be immediately scheduled when the main
thread releases the lock. */
#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 block_thread (void *lock_);
void
test_mlfqs_block (void)
{
int64_t start_time;
struct lock lock;
ASSERT (thread_mlfqs);
msg (“Main thread acquiring lock.”);
lock_init (&lock);
lock_acquire (&lock);
msg (“Main thread creating block thread, sleeping 25 seconds…”);
thread_create (“block”, PRI_DEFAULT, block_thread, &lock);
timer_sleep (25 * TIMER_FREQ);
msg (“Main thread spinning for 5 seconds…”);
start_time = timer_ticks ();
while (timer_elapsed (start_time) < 5 * TIMER_FREQ)
continue;
msg ("Main thread releasing lock.");
lock_release (&lock);
msg ("Block thread should have already acquired lock.");
}
static void
block_thread (void *lock_)
{
struct lock *lock = lock_;
int64_t start_time;
msg ("Block thread spinning for 20 seconds...");
start_time = timer_ticks ();
while (timer_elapsed (start_time) < 20 * TIMER_FREQ)
continue;
msg ("Block thread acquiring lock...");
lock_acquire (lock);
msg ("...got it.");
}