Add force_suspend function
This CL implements a simple force_suspend(). This function takes a
timeoutMs argument that is currently ignored. It also uses a two-stage
init process that spawns the suspend_thread when autosuspend is in use.
Follow-up CLs will:
- Implement file locking to prevent multiple libsuspend instances from
starting multiple suspend threads in the system.
- Fully implement timout for force_suspend.
- Integrate force_suspend with suspend_thred.
Bug: 70669809
Test: autosuspend still works
Change-Id: I6b2c72d0c61d1bec6db0f0b28481ffe0e20ec615
diff --git a/libsuspend/autosuspend_wakeup_count.cpp b/libsuspend/autosuspend_wakeup_count.cpp
index cfca765..27c8629 100644
--- a/libsuspend/autosuspend_wakeup_count.cpp
+++ b/libsuspend/autosuspend_wakeup_count.cpp
@@ -37,7 +37,7 @@
#define BASE_SLEEP_TIME 100000
#define MAX_SLEEP_TIME 60000000
-static int state_fd;
+static int state_fd = -1;
static int wakeup_count_fd;
using android::base::ReadFdToString;
@@ -46,11 +46,12 @@
static pthread_t suspend_thread;
static sem_t suspend_lockout;
-static const char* sleep_state = "mem";
+static constexpr char sleep_state[] = "mem";
static void (*wakeup_func)(bool success) = NULL;
static int sleep_time = BASE_SLEEP_TIME;
static constexpr char sys_power_state[] = "/sys/power/state";
static constexpr char sys_power_wakeup_count[] = "/sys/power/wakeup_count";
+static bool autosuspend_is_init = false;
static void update_sleep_time(bool success) {
if (success) {
@@ -62,10 +63,9 @@
}
static void* suspend_thread_func(void* arg __attribute__((unused))) {
- int ret;
bool success = true;
- while (1) {
+ while (true) {
update_sleep_time(success);
usleep(sleep_time);
success = false;
@@ -84,7 +84,7 @@
}
LOG(VERBOSE) << "wait";
- ret = sem_wait(&suspend_lockout);
+ int ret = sem_wait(&suspend_lockout);
if (ret < 0) {
PLOG(ERROR) << "error waiting on semaphore";
continue;
@@ -112,13 +112,72 @@
return NULL;
}
-static int autosuspend_wakeup_count_enable(void) {
- int ret;
+static int init_state_fd(void) {
+ if (state_fd >= 0) {
+ return 0;
+ }
+ int fd = TEMP_FAILURE_RETRY(open(sys_power_state, O_CLOEXEC | O_RDWR));
+ if (fd < 0) {
+ PLOG(ERROR) << "error opening " << sys_power_state;
+ return -1;
+ }
+
+ state_fd = fd;
+ LOG(INFO) << "init_state_fd success";
+ return 0;
+}
+
+static int autosuspend_init(void) {
+ if (autosuspend_is_init) {
+ return 0;
+ }
+
+ int ret = init_state_fd();
+ if (ret < 0) {
+ return -1;
+ }
+
+ wakeup_count_fd = TEMP_FAILURE_RETRY(open(sys_power_wakeup_count, O_CLOEXEC | O_RDWR));
+ if (wakeup_count_fd < 0) {
+ PLOG(ERROR) << "error opening " << sys_power_wakeup_count;
+ goto err_open_wakeup_count;
+ }
+
+ ret = sem_init(&suspend_lockout, 0, 0);
+ if (ret < 0) {
+ PLOG(ERROR) << "error creating suspend_lockout semaphore";
+ goto err_sem_init;
+ }
+
+ ret = pthread_create(&suspend_thread, NULL, suspend_thread_func, NULL);
+ if (ret) {
+ LOG(ERROR) << "error creating thread: " << strerror(ret);
+ goto err_pthread_create;
+ }
+
+ LOG(VERBOSE) << "autosuspend_init success";
+ autosuspend_is_init = true;
+ return 0;
+
+err_pthread_create:
+ sem_destroy(&suspend_lockout);
+err_sem_init:
+ close(wakeup_count_fd);
+err_open_wakeup_count:
+ return -1;
+}
+
+static int autosuspend_wakeup_count_enable(void) {
LOG(VERBOSE) << "autosuspend_wakeup_count_enable";
- ret = sem_post(&suspend_lockout);
+ int ret = autosuspend_init();
+ if (ret < 0) {
+ LOG(ERROR) << "autosuspend_init failed";
+ return ret;
+ }
+ ret = sem_post(&suspend_lockout);
if (ret < 0) {
PLOG(ERROR) << "error changing semaphore";
}
@@ -129,11 +188,13 @@
}
static int autosuspend_wakeup_count_disable(void) {
- int ret;
-
LOG(VERBOSE) << "autosuspend_wakeup_count_disable";
- ret = sem_wait(&suspend_lockout);
+ if (!autosuspend_is_init) {
+ return 0; // always successful if no thread is running yet
+ }
+
+ int ret = sem_wait(&suspend_lockout);
if (ret < 0) {
PLOG(ERROR) << "error changing semaphore";
@@ -144,6 +205,17 @@
return ret;
}
+static int force_suspend(int timeout_ms) {
+ LOG(VERBOSE) << "force_suspend called with timeout: " << timeout_ms;
+
+ int ret = init_state_fd();
+ if (ret < 0) {
+ return ret;
+ }
+
+ return WriteStringToFd(sleep_state, state_fd) ? 0 : -1;
+}
+
static void autosuspend_set_wakeup_callback(void (*func)(bool success)) {
if (wakeup_func != NULL) {
LOG(ERROR) << "duplicate wakeup callback applied, keeping original";
@@ -155,44 +227,10 @@
struct autosuspend_ops autosuspend_wakeup_count_ops = {
.enable = autosuspend_wakeup_count_enable,
.disable = autosuspend_wakeup_count_disable,
+ .force_suspend = force_suspend,
.set_wakeup_callback = autosuspend_set_wakeup_callback,
};
struct autosuspend_ops* autosuspend_wakeup_count_init(void) {
- int ret;
-
- state_fd = TEMP_FAILURE_RETRY(open(sys_power_state, O_RDWR));
- if (state_fd < 0) {
- PLOG(ERROR) << "error opening " << sys_power_state;
- goto err_open_state;
- }
-
- wakeup_count_fd = TEMP_FAILURE_RETRY(open(sys_power_wakeup_count, O_RDWR));
- if (wakeup_count_fd < 0) {
- PLOG(ERROR) << "error opening " << sys_power_wakeup_count;
- goto err_open_wakeup_count;
- }
-
- ret = sem_init(&suspend_lockout, 0, 0);
- if (ret < 0) {
- PLOG(ERROR) << "error creating semaphore";
- goto err_sem_init;
- }
- ret = pthread_create(&suspend_thread, NULL, suspend_thread_func, NULL);
- if (ret) {
- LOG(ERROR) << "error creating thread: " << strerror(ret);
- goto err_pthread_create;
- }
-
- LOG(INFO) << "selected wakeup count";
return &autosuspend_wakeup_count_ops;
-
-err_pthread_create:
- sem_destroy(&suspend_lockout);
-err_sem_init:
- close(wakeup_count_fd);
-err_open_wakeup_count:
- close(state_fd);
-err_open_state:
- return NULL;
}