From 4f670845ff9ab6c48bcb5f7bf4d4ef6dc3c3064b Mon Sep 17 00:00:00 2001 From: manuel Date: Tue, 27 Mar 2012 11:51:08 +0200 Subject: reorganize file structure to match the upstream requirements --- tests/threads/alarm-priority.c | 58 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 tests/threads/alarm-priority.c (limited to 'tests/threads/alarm-priority.c') diff --git a/tests/threads/alarm-priority.c b/tests/threads/alarm-priority.c new file mode 100644 index 0000000..2288ff6 --- /dev/null +++ b/tests/threads/alarm-priority.c @@ -0,0 +1,58 @@ +/* Checks that when the alarm clock wakes up threads, the + higher-priority threads run first. */ + +#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 thread_func alarm_priority_thread; +static int64_t wake_time; +static struct semaphore wait_sema; + +void +test_alarm_priority (void) +{ + int i; + + /* This test does not work with the MLFQS. */ + ASSERT (!thread_mlfqs); + + wake_time = timer_ticks () + 5 * TIMER_FREQ; + sema_init (&wait_sema, 0); + + for (i = 0; i < 10; i++) + { + int priority = PRI_DEFAULT - (i + 5) % 10 - 1; + char name[16]; + snprintf (name, sizeof name, "priority %d", priority); + thread_create (name, priority, alarm_priority_thread, NULL); + } + + thread_set_priority (PRI_MIN); + + for (i = 0; i < 10; i++) + sema_down (&wait_sema); +} + +static void +alarm_priority_thread (void *aux UNUSED) +{ + /* Busy-wait until the current time changes. */ + int64_t start_time = timer_ticks (); + while (timer_elapsed (start_time) == 0) + continue; + + /* Now we know we're at the very beginning of a timer tick, so + we can call timer_sleep() without worrying about races + between checking the time and a timer interrupt. */ + timer_sleep (wake_time - timer_ticks ()); + + /* Print a message on wake-up. */ + msg ("Thread %s woke up.", thread_name ()); + + sema_up (&wait_sema); +} -- cgit v1.2.3