blob: 00430bc5670128e3cdaef15857f0bbd2a3145f7a [file] [log] [blame]
// Copyright 2017 The Fuchsia Authors
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT
#include "tests.h"
#include <err.h>
#include <fbl/algorithm.h>
#include <fbl/atomic.h>
#include <inttypes.h>
#include <kernel/auto_lock.h>
#include <kernel/event.h>
#include <kernel/mp.h>
#include <kernel/spinlock.h>
#include <kernel/thread.h>
#include <kernel/timer.h>
#include <lib/unittest/unittest.h>
#include <malloc.h>
#include <platform.h>
#include <pow2.h>
#include <rand.h>
#include <stdio.h>
#include <zircon/time.h>
#include <zircon/types.h>
static void timer_diag_cb(timer_t* timer, zx_time_t now, void* arg) {
event_t* event = (event_t*)arg;
event_signal(event, true);
}
static int timer_do_one_thread(void* arg) {
event_t event;
timer_t timer;
event_init(&event, false, 0);
timer_init(&timer);
timer_set(&timer, current_time() + ZX_MSEC(10), TIMER_SLACK_CENTER, 0, timer_diag_cb, &event);
event_wait(&event);
printf("got timer on cpu %u\n", arch_curr_cpu_num());
event_destroy(&event);
return 0;
}
static void timer_diag_all_cpus(void) {
thread_t* timer_threads[SMP_MAX_CPUS];
uint max = arch_max_num_cpus();
uint i;
for (i = 0; i < max; i++) {
char name[16];
snprintf(name, sizeof(name), "timer %u\n", i);
timer_threads[i] = thread_create_etc(
NULL, name, timer_do_one_thread, NULL, DEFAULT_PRIORITY, NULL);
if (timer_threads[i] == NULL) {
printf("failed to create thread for cpu %u\n", i);
return;
}
thread_set_cpu_affinity(timer_threads[i], cpu_num_to_mask(i));
thread_resume(timer_threads[i]);
}
uint joined = 0;
for (i = 0; i < max; i++) {
if (thread_join(timer_threads[i], NULL, ZX_SEC(1)) == 0) {
joined += 1;
}
}
printf("%u threads created, %u threads joined\n", max, joined);
}
static void timer_diag_cb2(timer_t* timer, zx_time_t now, void* arg) {
auto timer_count = static_cast<fbl::atomic<size_t>*>(arg);
timer_count->fetch_add(1);
thread_preempt_set_pending();
}
static void timer_diag_coalescing(enum slack_mode mode, uint64_t slack, const zx_time_t* deadline,
const zx_duration_t* expected_adj, size_t count) {
printf("testing coalsecing mode %d\n", mode);
fbl::atomic<size_t> timer_count(0);
timer_t* timer = (timer_t*)malloc(sizeof(timer_t) * count);
printf(" orig new adjustment\n");
for (size_t ix = 0; ix != count; ++ix) {
timer_init(&timer[ix]);
zx_time_t dl = deadline[ix];
timer_set(&timer[ix], dl, mode, slack, timer_diag_cb2, &timer_count);
printf("[%zu] %" PRIi64 " -> %" PRIi64 ", %" PRIi64 "\n",
ix, dl, timer[ix].scheduled_time, timer[ix].slack);
if (timer[ix].slack != expected_adj[ix]) {
printf("\n!! unexpected adjustment! expected %" PRIi64 "\n", expected_adj[ix]);
}
}
// Wait for the timers to fire.
while (timer_count.load() != count) {
thread_sleep(current_time() + ZX_MSEC(5));
}
free(timer);
}
static void timer_diag_coalescing_center(void) {
zx_time_t when = current_time() + ZX_MSEC(1);
zx_duration_t off = ZX_USEC(10);
zx_duration_t slack = 2u * off;
const zx_time_t deadline[] = {
when + (6u * off), // non-coalesced, adjustment = 0
when, // non-coalesced, adjustment = 0
when - off, // coalesced with [1], adjustment = 10u
when - (3u * off), // non-coalesced, adjustment = 0
when + off, // coalesced with [1], adjustment = -10u
when + (3u * off), // non-coalesced, adjustment = 0
when + (5u * off), // coalesced with [0], adjustment = 10u
when - (3u * off), // non-coalesced, same as [3], adjustment = 0
};
const zx_duration_t expected_adj[fbl::count_of(deadline)] = {
0, 0, ZX_USEC(10), 0, -ZX_USEC(10), 0, ZX_USEC(10), 0};
timer_diag_coalescing(
TIMER_SLACK_CENTER, slack, deadline, expected_adj, fbl::count_of(deadline));
}
static void timer_diag_coalescing_late(void) {
zx_time_t when = current_time() + ZX_MSEC(1);
zx_duration_t off = ZX_USEC(10);
zx_duration_t slack = 3u * off;
const zx_time_t deadline[] = {
when + off, // non-coalesced, adjustment = 0
when + (2u * off), // non-coalesced, adjustment = 0
when - off, // coalesced with [0], adjustment = 20u
when - (3u * off), // non-coalesced, adjustment = 0
when + (3u * off), // non-coalesced, adjustment = 0
when + (2u * off), // non-coalesced, same as [1]
when - (4u * off), // coalesced with [3], adjustment = 10u
};
const zx_duration_t expected_adj[fbl::count_of(deadline)] = {
0, 0, ZX_USEC(20), 0, 0, 0, ZX_USEC(10)};
timer_diag_coalescing(
TIMER_SLACK_LATE, slack, deadline, expected_adj, fbl::count_of(deadline));
}
static void timer_diag_coalescing_early(void) {
zx_time_t when = current_time() + ZX_MSEC(1);
zx_duration_t off = ZX_USEC(10);
zx_duration_t slack = 3u * off;
const zx_time_t deadline[] = {
when, // non-coalesced, adjustment = 0
when + (2u * off), // coalesced with [0], adjustment = -20u
when - off, // non-coalesced, adjustment = 0
when - (3u * off), // non-coalesced, adjustment = 0
when + (4u * off), // non-coalesced, adjustment = 0
when + (5u * off), // coalesced with [4], adjustment = -10u
when - (2u * off), // coalesced with [3], adjustment = -10u
};
const zx_duration_t expected_adj[fbl::count_of(deadline)] = {
0, -ZX_USEC(20), 0, 0, 0, -ZX_USEC(10), -ZX_USEC(10)};
timer_diag_coalescing(
TIMER_SLACK_EARLY, slack, deadline, expected_adj, fbl::count_of(deadline));
}
static void timer_far_deadline(void) {
event_t event;
timer_t timer;
event_init(&event, false, 0);
timer_init(&timer);
timer_set(&timer, ZX_TIME_INFINITE - 5, TIMER_SLACK_CENTER, 0, timer_diag_cb, &event);
zx_status_t st = event_wait_deadline(&event, current_time() + ZX_MSEC(100), false);
if (st != ZX_ERR_TIMED_OUT) {
printf("error: unexpected timer fired!\n");
} else {
timer_cancel(&timer);
}
event_destroy(&event);
}
// Print timer diagnostics for manual review.
int timer_diag(int, const cmd_args*, uint32_t) {
timer_diag_coalescing_center();
timer_diag_coalescing_late();
timer_diag_coalescing_early();
timer_diag_all_cpus();
timer_far_deadline();
return 0;
}
struct timer_stress_args {
volatile int timer_stress_done;
volatile uint64_t num_set;
volatile uint64_t num_fired;
};
static void timer_stress_cb(struct timer* t, zx_time_t now, void* void_arg) {
timer_stress_args* args = reinterpret_cast<timer_stress_args*>(void_arg);
atomic_add_u64(&args->num_fired, 1);
}
// Returns a random duration between 0 and max (inclusive).
static zx_duration_t rand_duration(zx_duration_t max) {
return (zx_duration_mul_int64(max, rand())) / RAND_MAX;
}
static int timer_stress_worker(void* void_arg) {
timer_stress_args* args = reinterpret_cast<timer_stress_args*>(void_arg);
while (!atomic_load(&args->timer_stress_done)) {
timer_t t = TIMER_INITIAL_VALUE(t);
zx_duration_t timer_duration = rand_duration(ZX_MSEC(5));
// Set a timer, then switch to a different CPU to ensure we race with it.
arch_disable_ints();
uint timer_cpu = arch_curr_cpu_num();
timer_set(&t, current_time() + timer_duration, TIMER_SLACK_CENTER, 0, timer_stress_cb,
void_arg);
thread_set_cpu_affinity(get_current_thread(), ~cpu_num_to_mask(timer_cpu));
DEBUG_ASSERT(arch_curr_cpu_num() != timer_cpu);
arch_enable_ints();
// We're now running on something other than timer_cpu.
atomic_add_u64(&args->num_set, 1);
// Sleep for the timer duration so that this thread's timer_cancel races with the timer
// callback. We want to race to ensure there are no synchronization or memory visibility
// issues.
thread_sleep_relative(timer_duration);
timer_cancel(&t);
}
return 0;
}
static unsigned get_num_cpus_online() {
unsigned count = 0;
cpu_mask_t online = mp_get_online_mask();
while (online) {
online >>= 1;
++count;
}
return count;
}
// timer_stress is a simple stress test intended to flush out bugs in kernel timers.
int timer_stress(int argc, const cmd_args* argv, uint32_t) {
if (argc < 2) {
printf("not enough args\n");
printf("usage: %s <num seconds>\n", argv[0].str);
return ZX_ERR_INTERNAL;
}
// We need 2 or more CPUs for this test.
if (get_num_cpus_online() < 2) {
printf("not enough online cpus\n");
return ZX_ERR_INTERNAL;
}
timer_stress_args args{};
thread_t* threads[256];
for (auto& thread : threads) {
thread =
thread_create("timer-stress-worker", &timer_stress_worker, &args, DEFAULT_PRIORITY);
}
printf("running for %zu seconds\n", argv[1].u);
for (const auto& thread : threads) {
thread_resume(thread);
}
thread_sleep_relative(ZX_SEC(argv[1].u));
atomic_store(&args.timer_stress_done, 1);
for (const auto& thread : threads) {
thread_join(thread, nullptr, ZX_TIME_INFINITE);
}
printf("timer stress done; timer set %zu, timer fired %zu\n", args.num_set, args.num_fired);
return 0;
}
struct timer_args {
volatile int result;
volatile int timer_fired;
volatile int remaining;
volatile int wait;
spin_lock_t* lock;
};
static void timer_cb(struct timer*, zx_time_t now, void* void_arg) {
timer_args* arg = reinterpret_cast<timer_args*>(void_arg);
atomic_store(&arg->timer_fired, 1);
}
// Set a timer and cancel it before the deadline has elapsed.
static bool cancel_before_deadline() {
BEGIN_TEST;
timer_args arg{};
timer_t t = TIMER_INITIAL_VALUE(t);
timer_set(&t, current_time() + ZX_HOUR(5), TIMER_SLACK_CENTER, 0, timer_cb, &arg);
ASSERT_TRUE(timer_cancel(&t), "");
ASSERT_FALSE(atomic_load(&arg.timer_fired), "");
END_TEST;
}
// Set a timer and cancel it after it has fired.
static bool cancel_after_fired() {
BEGIN_TEST;
timer_args arg{};
timer_t t = TIMER_INITIAL_VALUE(t);
timer_set(&t, current_time(), TIMER_SLACK_CENTER, 0, timer_cb, &arg);
while (!atomic_load(&arg.timer_fired)) {
}
ASSERT_FALSE(timer_cancel(&t), "");
END_TEST;
}
static void timer_cancel_cb(struct timer* t, zx_time_t now, void* void_arg) {
timer_args* arg = reinterpret_cast<timer_args*>(void_arg);
atomic_store(&arg->result, timer_cancel(t));
atomic_store(&arg->timer_fired, 1);
}
// Set a timer and cancel it from its own callback.
static bool cancel_from_callback() {
BEGIN_TEST;
timer_args arg{};
arg.result = 1;
timer_t t = TIMER_INITIAL_VALUE(t);
timer_set(&t, current_time(), TIMER_SLACK_CENTER, 0, timer_cancel_cb, &arg);
while (!atomic_load(&arg.timer_fired)) {
}
ASSERT_FALSE(arg.result, "");
ASSERT_FALSE(timer_cancel(&t), "");
END_TEST;
}
static void timer_set_cb(struct timer* t, zx_time_t now, void* void_arg) {
timer_args* arg = reinterpret_cast<timer_args*>(void_arg);
if (atomic_add(&arg->remaining, -1) >= 1) {
timer_set(t, current_time() + ZX_USEC(10), TIMER_SLACK_CENTER, 0, timer_set_cb, void_arg);
}
}
// Set a timer that re-sets itself from its own callback.
static bool set_from_callback() {
BEGIN_TEST;
timer_args arg{};
arg.remaining = 5;
timer_t t = TIMER_INITIAL_VALUE(t);
timer_set(&t, current_time(), TIMER_SLACK_CENTER, 0, timer_set_cb, &arg);
while (atomic_load(&arg.remaining) > 0) {
}
// We cannot assert the return value below because we don't know if the last timer has fired.
timer_cancel(&t);
END_TEST;
}
static void timer_trylock_cb(struct timer* t, zx_time_t now, void* void_arg) {
timer_args* arg = reinterpret_cast<timer_args*>(void_arg);
atomic_store(&arg->timer_fired, 1);
while (atomic_load(&arg->wait)) {
}
int result = timer_trylock_or_cancel(t, arg->lock);
if (!result) {
spin_unlock(arg->lock);
}
atomic_store(&arg->result, result);
}
// See that timer_trylock_or_cancel spins until the timer is canceled.
static bool trylock_or_cancel_canceled() {
BEGIN_TEST;
// We need 2 or more CPUs for this test.
if (get_num_cpus_online() < 2) {
printf("skipping test trylock_or_cancel_canceled, not enough online cpus\n");
return true;
}
timer_args arg{};
timer_t t = TIMER_INITIAL_VALUE(t);
SpinLock lock;
arg.lock = lock.GetInternal();
arg.wait = 1;
arch_disable_ints();
uint timer_cpu = arch_curr_cpu_num();
timer_set(&t, current_time() + ZX_USEC(100), TIMER_SLACK_CENTER, 0, timer_trylock_cb, &arg);
// The timer is set to run on timer_cpu, switch to a different CPU, acquire the spinlock then
// signal the callback to proceed.
thread_set_cpu_affinity(get_current_thread(), ~cpu_num_to_mask(timer_cpu));
DEBUG_ASSERT(arch_curr_cpu_num() != timer_cpu);
arch_enable_ints();
{
AutoSpinLock guard(&lock);
while (!atomic_load(&arg.timer_fired)) {
}
// Callback should now be running. Tell it to stop waiting and start trylocking.
atomic_store(&arg.wait, 0);
// See that timer_cancel returns false indicating that the timer ran.
ASSERT_FALSE(timer_cancel(&t), "");
}
// See that the timer failed to acquire the lock.
ASSERT_TRUE(arg.result, "");
END_TEST;
}
// See that timer_trylock_or_cancel acquires the lock when the holder releases it.
static bool trylock_or_cancel_get_lock() {
BEGIN_TEST;
// We need 2 or more CPUs for this test.
if (get_num_cpus_online() < 2) {
printf("skipping test trylock_or_cancel_get_lock, not enough online cpus\n");
return true;
}
timer_args arg{};
timer_t t = TIMER_INITIAL_VALUE(t);
SpinLock lock;
arg.lock = lock.GetInternal();
arg.wait = 1;
arch_disable_ints();
uint timer_cpu = arch_curr_cpu_num();
timer_set(&t, current_time() + ZX_USEC(100), TIMER_SLACK_CENTER, 0, timer_trylock_cb, &arg);
// The timer is set to run on timer_cpu, switch to a different CPU, acquire the spinlock then
// signal the callback to proceed.
thread_set_cpu_affinity(get_current_thread(), ~cpu_num_to_mask(timer_cpu));
DEBUG_ASSERT(arch_curr_cpu_num() != timer_cpu);
arch_enable_ints();
{
AutoSpinLock guard(&lock);
while (!atomic_load(&arg.timer_fired)) {
}
// Callback should now be running. Tell it to stop waiting and start trylocking.
atomic_store(&arg.wait, 0);
}
// See that timer_cancel returns false indicating that the timer ran.
ASSERT_FALSE(timer_cancel(&t), "");
// Note, we cannot assert the value of arg.result. We have both released the lock and canceled
// the timer, but we don't know which of these events the timer observed first.
END_TEST;
}
UNITTEST_START_TESTCASE(timer_tests)
UNITTEST("cancel_before_deadline", cancel_before_deadline)
UNITTEST("cancel_after_fired", cancel_after_fired)
UNITTEST("cancel_from_callback", cancel_from_callback)
UNITTEST("set_from_callback", set_from_callback)
UNITTEST("trylock_or_cancel_canceled", trylock_or_cancel_canceled)
UNITTEST("trylock_or_cancel_get_lock", trylock_or_cancel_get_lock)
UNITTEST_END_TESTCASE(timer_tests, "timer", "timer tests");