scrcpy/app/src/fps_counter.c
Romain Vimont e604e8a752 Move fps_counter to screen
The FPS counter specifically count frames from the screen video buffer,
so it is specific to the screen.
2021-05-16 18:47:16 +02:00

185 lines
4.8 KiB
C

#include "fps_counter.h"
#include <assert.h>
#include <SDL2/SDL_timer.h>
#include "util/log.h"
#define FPS_COUNTER_INTERVAL_MS 1000
bool
fps_counter_init(struct fps_counter *counter) {
bool ok = sc_mutex_init(&counter->mutex);
if (!ok) {
return false;
}
ok = sc_cond_init(&counter->state_cond);
if (!ok) {
sc_mutex_destroy(&counter->mutex);
return false;
}
counter->thread_started = false;
atomic_init(&counter->started, 0);
// no need to initialize the other fields, they are unused until started
return true;
}
void
fps_counter_destroy(struct fps_counter *counter) {
sc_cond_destroy(&counter->state_cond);
sc_mutex_destroy(&counter->mutex);
}
static inline bool
is_started(struct fps_counter *counter) {
return atomic_load_explicit(&counter->started, memory_order_acquire);
}
static inline void
set_started(struct fps_counter *counter, bool started) {
atomic_store_explicit(&counter->started, started, memory_order_release);
}
// must be called with mutex locked
static void
display_fps(struct fps_counter *counter) {
unsigned rendered_per_second =
counter->nr_rendered * 1000 / FPS_COUNTER_INTERVAL_MS;
if (counter->nr_skipped) {
LOGI("%u fps (+%u frames skipped)", rendered_per_second,
counter->nr_skipped);
} else {
LOGI("%u fps", rendered_per_second);
}
}
// must be called with mutex locked
static void
check_interval_expired(struct fps_counter *counter, uint32_t now) {
if (now < counter->next_timestamp) {
return;
}
display_fps(counter);
counter->nr_rendered = 0;
counter->nr_skipped = 0;
// add a multiple of the interval
uint32_t elapsed_slices =
(now - counter->next_timestamp) / FPS_COUNTER_INTERVAL_MS + 1;
counter->next_timestamp += FPS_COUNTER_INTERVAL_MS * elapsed_slices;
}
static int
run_fps_counter(void *data) {
struct fps_counter *counter = data;
sc_mutex_lock(&counter->mutex);
while (!counter->interrupted) {
while (!counter->interrupted && !is_started(counter)) {
sc_cond_wait(&counter->state_cond, &counter->mutex);
}
while (!counter->interrupted && is_started(counter)) {
uint32_t now = SDL_GetTicks();
check_interval_expired(counter, now);
assert(counter->next_timestamp > now);
uint32_t remaining = counter->next_timestamp - now;
// ignore the reason (timeout or signaled), we just loop anyway
sc_cond_timedwait(&counter->state_cond, &counter->mutex, remaining);
}
}
sc_mutex_unlock(&counter->mutex);
return 0;
}
bool
fps_counter_start(struct fps_counter *counter) {
sc_mutex_lock(&counter->mutex);
counter->next_timestamp = SDL_GetTicks() + FPS_COUNTER_INTERVAL_MS;
counter->nr_rendered = 0;
counter->nr_skipped = 0;
sc_mutex_unlock(&counter->mutex);
set_started(counter, true);
sc_cond_signal(&counter->state_cond);
// counter->thread_started and counter->thread are always accessed from the
// same thread, no need to lock
if (!counter->thread_started) {
bool ok = sc_thread_create(&counter->thread, run_fps_counter,
"fps counter", counter);
if (!ok) {
LOGE("Could not start FPS counter thread");
return false;
}
counter->thread_started = true;
}
return true;
}
void
fps_counter_stop(struct fps_counter *counter) {
set_started(counter, false);
sc_cond_signal(&counter->state_cond);
}
bool
fps_counter_is_started(struct fps_counter *counter) {
return is_started(counter);
}
void
fps_counter_interrupt(struct fps_counter *counter) {
if (!counter->thread_started) {
return;
}
sc_mutex_lock(&counter->mutex);
counter->interrupted = true;
sc_mutex_unlock(&counter->mutex);
// wake up blocking wait
sc_cond_signal(&counter->state_cond);
}
void
fps_counter_join(struct fps_counter *counter) {
if (counter->thread_started) {
// interrupted must be set by the thread calling join(), so no need to
// lock for the assertion
assert(counter->interrupted);
sc_thread_join(&counter->thread, NULL);
}
}
void
fps_counter_add_rendered_frame(struct fps_counter *counter) {
if (!is_started(counter)) {
return;
}
sc_mutex_lock(&counter->mutex);
uint32_t now = SDL_GetTicks();
check_interval_expired(counter, now);
++counter->nr_rendered;
sc_mutex_unlock(&counter->mutex);
}
void
fps_counter_add_skipped_frame(struct fps_counter *counter) {
if (!is_started(counter)) {
return;
}
sc_mutex_lock(&counter->mutex);
uint32_t now = SDL_GetTicks();
check_interval_expired(counter, now);
++counter->nr_skipped;
sc_mutex_unlock(&counter->mutex);
}