@@ -48,6 +48,19 @@ extern ReplayMode replay_mode;
/* Name of the initial VM snapshot */
extern char *replay_snapshot;
+/* Replay locking
+ *
+ * The locks are needed to protect the shared structures and log file
+ * when doing record/replay. They also are the main sync-point between
+ * the main-loop thread and the vCPU thread. This was a role
+ * previously filled by the BQL which has been busy trying to reduce
+ * its impact across the code. This ensures blocks of events stay
+ * sequential and reproducible.
+ */
+
+void replay_mutex_lock(void);
+void replay_mutex_unlock(void);
+
/* Replay process control functions */
/*! Enables recording or saving event log with specified parameters */
@@ -181,7 +181,7 @@ void replay_mutex_destroy(void)
qemu_mutex_destroy(&lock);
}
-static bool replay_mutex_locked(void)
+bool replay_mutex_locked(void)
{
return replay_locked;
}
@@ -100,12 +100,12 @@ int64_t replay_get_qword(void);
void replay_get_array(uint8_t *buf, size_t *size);
void replay_get_array_alloc(uint8_t **buf, size_t *size);
-/* Mutex functions for protecting replay log file */
+/* Mutex functions for protecting replay log file and ensuring
+ * synchronisation between vCPU and main-loop threads. */
void replay_mutex_init(void);
void replay_mutex_destroy(void);
-void replay_mutex_lock(void);
-void replay_mutex_unlock(void);
+bool replay_mutex_locked(void);
/*! Checks error status of the file. */
void replay_check_error(void);
@@ -72,3 +72,11 @@ uint64_t blkreplay_next_id(void)
{
return 0;
}
+
+void replay_mutex_lock(void)
+{
+}
+
+void replay_mutex_unlock(void)
+{
+}