Changes in uspace/lib/c/generic/fibril_synch.c [45cbcaf4:2654afb] in mainline

File:

• uspace/lib/c/generic/fibril_synch.c (modified) (12 diffs)

uspace/lib/c/generic/fibril_synch.c

@@ -105 +105 @@
         fibril_t *f = (fibril_t *) fibril_get_id();
 
-        if (fibril_get_sercount() != 0)
-                abort();
-
         futex_down(&async_futex);
         if (fm->counter-- <= 0) {
@@ -197 +194 @@
         fibril_t *f = (fibril_t *) fibril_get_id();
         
-        if (fibril_get_sercount() != 0)
-                abort();
-
         futex_down(&async_futex);
         if (frw->writers) {
@@ -224 +218 @@
         fibril_t *f = (fibril_t *) fibril_get_id();
         
-        if (fibril_get_sercount() != 0)
-                abort();
-
         futex_down(&async_futex);
         if (frw->writers || frw->readers) {
@@ -380 +371 @@
         if (timeout) {
                 getuptime(&wdata.to_event.expires);
-                tv_add(&wdata.to_event.expires, timeout);
+                tv_add_diff(&wdata.to_event.expires, timeout);
                 async_insert_timeout(&wdata);
         }
@@ -448 +439 @@
         int rc;
 
-        fibril_mutex_lock(&timer->lock);
-
-        while (true) {
-                while (timer->state != fts_active &&
-                    timer->state != fts_cleanup) {
-
-                        if (timer->state == fts_cleanup)
-                                break;
-
-                        fibril_condvar_wait(&timer->cv, &timer->lock);
+        fibril_mutex_lock(timer->lockp);
+
+        while (timer->state != fts_cleanup) {
+                switch (timer->state) {
+                case fts_not_set:
+                case fts_fired:
+                        fibril_condvar_wait(&timer->cv, timer->lockp);
+                        break;
+                case fts_active:
+                        rc = fibril_condvar_wait_timeout(&timer->cv,
+                            timer->lockp, timer->delay);
+                        if (rc == ETIMEOUT && timer->state == fts_active) {
+                                timer->state = fts_fired;
+                                timer->handler_fid = fibril_get_id();
+                                fibril_mutex_unlock(timer->lockp);
+                                timer->fun(timer->arg);
+                                fibril_mutex_lock(timer->lockp);
+                                timer->handler_fid = 0;
+                        }
+                        break;
+                case fts_cleanup:
+                case fts_clean:
+                        assert(false);
+                        break;
                 }
-
-                if (timer->state == fts_cleanup)
-                        break;
-
-                rc = fibril_condvar_wait_timeout(&timer->cv, &timer->lock,
-                    timer->delay);
-                if (rc == ETIMEOUT) {
-                        timer->state = fts_fired;
-                        fibril_mutex_unlock(&timer->lock);
-                        timer->fun(timer->arg);
-                        fibril_mutex_lock(&timer->lock);
-                }
-        }
-
-        fibril_mutex_unlock(&timer->lock);
+        }
+
+        /* Acknowledge timer fibril has finished cleanup. */
+        timer->state = fts_clean;
+        fibril_condvar_broadcast(&timer->cv);
+        fibril_mutex_unlock(timer->lockp);
+
         return 0;
 }
@@ -481 +478 @@
  * @return              New timer on success, @c NULL if out of memory.
  */
-fibril_timer_t *fibril_timer_create(void)
+fibril_timer_t *fibril_timer_create(fibril_mutex_t *lock)
 {
         fid_t fid;
@@ -501 +498 @@
         timer->fibril = fid;
         timer->state = fts_not_set;
+        timer->lockp = (lock != NULL) ? lock : &timer->lock;
 
         fibril_add_ready(fid);
-
         return timer;
 }
@@ -513 +510 @@
 void fibril_timer_destroy(fibril_timer_t *timer)
 {
-        fibril_mutex_lock(&timer->lock);
-        assert(timer->state != fts_active);
+        fibril_mutex_lock(timer->lockp);
+        assert(timer->state == fts_not_set || timer->state == fts_fired);
+
+        /* Request timer fibril to terminate. */
         timer->state = fts_cleanup;
         fibril_condvar_broadcast(&timer->cv);
-        fibril_mutex_unlock(&timer->lock);
+
+        /* Wait for timer fibril to terminate */
+        while (timer->state != fts_clean)
+                fibril_condvar_wait(&timer->cv, timer->lockp);
+        fibril_mutex_unlock(timer->lockp);
+
+        free(timer);
 }
 
@@ -533 +538 @@
     fibril_timer_fun_t fun, void *arg)
 {
-        fibril_mutex_lock(&timer->lock);
+        fibril_mutex_lock(timer->lockp);
+        fibril_timer_set_locked(timer, delay, fun, arg);
+        fibril_mutex_unlock(timer->lockp);
+}
+
+/** Set locked timer.
+ *
+ * Set timer to execute a callback function after the specified
+ * interval. Must be called when the timer is locked.
+ *
+ * @param timer         Timer
+ * @param delay         Delay in microseconds
+ * @param fun           Callback function
+ * @param arg           Argument for @a fun
+ */
+void fibril_timer_set_locked(fibril_timer_t *timer, suseconds_t delay,
+    fibril_timer_fun_t fun, void *arg)
+{
+        assert(fibril_mutex_is_locked(timer->lockp));
+        assert(timer->state == fts_not_set || timer->state == fts_fired);
         timer->state = fts_active;
         timer->delay = delay;
@@ -539 +563 @@
         timer->arg = arg;
         fibril_condvar_broadcast(&timer->cv);
-        fibril_mutex_unlock(&timer->lock);
 }
 
@@ -557 +580 @@
         fibril_timer_state_t old_state;
 
-        fibril_mutex_lock(&timer->lock);
+        fibril_mutex_lock(timer->lockp);
+        old_state = fibril_timer_clear_locked(timer);
+        fibril_mutex_unlock(timer->lockp);
+
+        return old_state;
+}
+
+/** Clear locked timer.
+ *
+ * Clears (cancels) timer and returns last state of the timer.
+ * This can be one of:
+ *    - fts_not_set     If the timer has not been set or has been cleared
+ *    - fts_active      Timer was set but did not fire
+ *    - fts_fired       Timer fired
+ * Must be called when the timer is locked.
+ *
+ * @param timer         Timer
+ * @return              Last timer state
+ */
+fibril_timer_state_t fibril_timer_clear_locked(fibril_timer_t *timer)
+{
+        fibril_timer_state_t old_state;
+
+        assert(fibril_mutex_is_locked(timer->lockp));
+
+        while (timer->handler_fid != 0) {
+                if (timer->handler_fid == fibril_get_id()) {
+                        printf("Deadlock detected.\n");
+                        stacktrace_print();
+                        printf("Fibril %zx is trying to clear timer %p from "
+                            "inside its handler %p.\n",
+                            fibril_get_id(), timer, timer->fun);
+                        abort();
+                }
+
+                fibril_condvar_wait(&timer->cv, timer->lockp);
+        }
+
         old_state = timer->state;
         timer->state = fts_not_set;
@@ -565 +625 @@
         timer->arg = NULL;
         fibril_condvar_broadcast(&timer->cv);
-        fibril_mutex_unlock(&timer->lock);
 
         return old_state;