@@ -84,8 +84,7 @@ void icount_handle_deadline(void)
* Don't interrupt cpu thread, when these events are waiting
* (i.e., there is no checkpoint)
*/
- if (deadline == 0
- && (replay_mode != REPLAY_MODE_PLAY || replay_has_checkpoint())) {
+ if (deadline == 0) {
icount_notify_aio_contexts();
}
}
@@ -109,7 +108,7 @@ void icount_prepare_for_run(CPUState *cpu)
replay_mutex_lock();
- if (cpu->icount_budget == 0 && replay_has_checkpoint()) {
+ if (cpu->icount_budget == 0) {
icount_notify_aio_contexts();
}
}
@@ -366,11 +366,9 @@ Here is the list of events that are written into the log:
Argument: 4-byte number of executed instructions.
- EVENT_INTERRUPT. Used to synchronize interrupt processing.
- EVENT_EXCEPTION. Used to synchronize exception handling.
- - EVENT_ASYNC. This is a group of events. They are always processed
- together with checkpoints. When such an event is generated, it is
- stored in the queue and processed only when checkpoint occurs.
- Every such event is followed by 1-byte checkpoint id and 1-byte
- async event id from the following list:
+ - EVENT_ASYNC. This is a group of events. When such an event is generated,
+ it is stored in the queue and processed in icount_account_warp_timer().
+ Every such event has it's own id from the following list:
- REPLAY_ASYNC_EVENT_BH. Bottom-half callback. This event synchronizes
callbacks that affect virtual machine state, but normally called
asynchronously.
@@ -405,6 +403,5 @@ Here is the list of events that are written into the log:
- EVENT_CLOCK + clock_id. Group of events for host clock read operations.
Argument: 8-byte clock value.
- EVENT_CHECKPOINT + checkpoint_id. Checkpoint for synchronization of
- CPU, internal threads, and asynchronous input events. May be followed
- by one or more EVENT_ASYNC events.
+ CPU, internal threads, and asynchronous input events.
- EVENT_END. Last event in the log.
@@ -161,9 +161,14 @@ void replay_shutdown_request(ShutdownCause cause);
Returns 0 in PLAY mode if checkpoint was not found.
Returns 1 in all other cases. */
bool replay_checkpoint(ReplayCheckpoint checkpoint);
-/*! Used to determine that checkpoint is pending.
+/*! Used to determine that checkpoint or async event is pending.
Does not proceed to the next event in the log. */
-bool replay_has_checkpoint(void);
+bool replay_has_event(void);
+/*
+ * Processes the async events added to the queue (while recording)
+ * or reads the events from the file (while replaying).
+ */
+void replay_async_events(void);
/* Asynchronous events queue */
@@ -170,12 +170,11 @@ void replay_block_event(QEMUBH *bh, uint64_t id)
}
}
-static void replay_save_event(Event *event, int checkpoint)
+static void replay_save_event(Event *event)
{
if (replay_mode != REPLAY_MODE_PLAY) {
/* put the event into the file */
replay_put_event(EVENT_ASYNC);
- replay_put_byte(checkpoint);
replay_put_byte(event->event_kind);
/* save event-specific data */
@@ -206,34 +205,27 @@ static void replay_save_event(Event *event, int checkpoint)
}
/* Called with replay mutex locked */
-void replay_save_events(int checkpoint)
+void replay_save_events(void)
{
g_assert(replay_mutex_locked());
- g_assert(checkpoint != CHECKPOINT_CLOCK_WARP_START);
- g_assert(checkpoint != CHECKPOINT_CLOCK_VIRTUAL);
while (!QTAILQ_EMPTY(&events_list)) {
Event *event = QTAILQ_FIRST(&events_list);
- replay_save_event(event, checkpoint);
+ replay_save_event(event);
replay_run_event(event);
QTAILQ_REMOVE(&events_list, event, events);
g_free(event);
}
}
-static Event *replay_read_event(int checkpoint)
+static Event *replay_read_event(void)
{
Event *event;
if (replay_state.read_event_kind == -1) {
- replay_state.read_event_checkpoint = replay_get_byte();
replay_state.read_event_kind = replay_get_byte();
replay_state.read_event_id = -1;
replay_check_error();
}
- if (checkpoint != replay_state.read_event_checkpoint) {
- return NULL;
- }
-
/* Events that has not to be in the queue */
switch (replay_state.read_event_kind) {
case REPLAY_ASYNC_EVENT_BH:
@@ -294,11 +286,11 @@ static Event *replay_read_event(int checkpoint)
}
/* Called with replay mutex locked */
-void replay_read_events(int checkpoint)
+void replay_read_events(void)
{
g_assert(replay_mutex_locked());
while (replay_state.data_kind == EVENT_ASYNC) {
- Event *event = replay_read_event(checkpoint);
+ Event *event = replay_read_event();
if (!event) {
break;
}
@@ -87,8 +87,6 @@ typedef struct ReplayState {
int32_t read_event_kind;
/*! Asynchronous event id read from the log */
uint64_t read_event_id;
- /*! Asynchronous event checkpoint id read from the log */
- int32_t read_event_checkpoint;
} ReplayState;
extern ReplayState replay_state;
@@ -151,9 +149,9 @@ void replay_finish_events(void);
/*! Returns true if there are any unsaved events in the queue */
bool replay_has_events(void);
/*! Saves events from queue into the file */
-void replay_save_events(int checkpoint);
+void replay_save_events(void);
/*! Read events from the file into the input queue */
-void replay_read_events(int checkpoint);
+void replay_read_events(void);
/*! Adds specified async event to the queue */
void replay_add_event(ReplayAsyncEventKind event_kind, void *opaque,
void *opaque2, uint64_t id);
@@ -61,7 +61,6 @@ static const VMStateDescription vmstate_replay = {
VMSTATE_UINT64(block_request_id, ReplayState),
VMSTATE_INT32(read_event_kind, ReplayState),
VMSTATE_UINT64(read_event_id, ReplayState),
- VMSTATE_INT32(read_event_checkpoint, ReplayState),
VMSTATE_END_OF_LIST()
},
};
@@ -22,7 +22,7 @@
/* Current version of the replay mechanism.
Increase it when file format changes. */
-#define REPLAY_VERSION 0xe0200a
+#define REPLAY_VERSION 0xe0200b
/* Size of replay log header */
#define HEADER_SIZE (sizeof(uint32_t) + sizeof(uint64_t))
@@ -171,64 +171,49 @@ void replay_shutdown_request(ShutdownCause cause)
bool replay_checkpoint(ReplayCheckpoint checkpoint)
{
- bool res = false;
- static bool in_checkpoint;
assert(EVENT_CHECKPOINT + checkpoint <= EVENT_CHECKPOINT_LAST);
- if (!replay_file) {
- return true;
- }
-
- if (in_checkpoint) {
- /*
- Recursion occurs when HW event modifies timers.
- Prevent performing icount warp in this case and
- wait for another invocation of the checkpoint.
- */
- g_assert(replay_mode == REPLAY_MODE_PLAY);
- return false;
- }
- in_checkpoint = true;
-
replay_save_instructions();
if (replay_mode == REPLAY_MODE_PLAY) {
g_assert(replay_mutex_locked());
if (replay_next_event_is(EVENT_CHECKPOINT + checkpoint)) {
replay_finish_event();
- } else if (replay_state.data_kind != EVENT_ASYNC) {
- res = false;
- goto out;
+ } else {
+ return false;
}
- replay_read_events(checkpoint);
- /* replay_read_events may leave some unread events.
- Return false if not all of the events associated with
- checkpoint were processed */
- res = replay_state.data_kind != EVENT_ASYNC;
} else if (replay_mode == REPLAY_MODE_RECORD) {
g_assert(replay_mutex_locked());
replay_put_event(EVENT_CHECKPOINT + checkpoint);
- /* This checkpoint belongs to several threads.
- Processing events from different threads is
- non-deterministic */
- if (checkpoint != CHECKPOINT_CLOCK_WARP_START
- /* FIXME: this is temporary fix, other checkpoints
- may also be invoked from the different threads someday.
- Asynchronous event processing should be refactored
- to create additional replay event kind which is
- nailed to the one of the threads and which processes
- the event queue. */
- && checkpoint != CHECKPOINT_CLOCK_VIRTUAL) {
- replay_save_events(checkpoint);
- }
- res = true;
}
-out:
- in_checkpoint = false;
- return res;
+ return true;
+}
+
+void replay_async_events(void)
+{
+ static bool processing = false;
+ /*
+ * If we are already processing the events, recursion may occur
+ * in case of incorrect implementation when HW event modifies timers.
+ * Timer modification may invoke the icount warp, event processing,
+ * and cause the recursion.
+ */
+ g_assert(!processing);
+ processing = true;
+
+ replay_save_instructions();
+
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ g_assert(replay_mutex_locked());
+ replay_read_events();
+ } else if (replay_mode == REPLAY_MODE_RECORD) {
+ g_assert(replay_mutex_locked());
+ replay_save_events();
+ }
+ processing = false;
}
-bool replay_has_checkpoint(void)
+bool replay_has_event(void)
{
bool res = false;
if (replay_mode == REPLAY_MODE_PLAY) {
@@ -236,6 +221,7 @@ bool replay_has_checkpoint(void)
replay_account_executed_instructions();
res = EVENT_CHECKPOINT <= replay_state.data_kind
&& replay_state.data_kind <= EVENT_CHECKPOINT_LAST;
+ res = res || replay_state.data_kind == EVENT_ASYNC;
}
return res;
}
@@ -322,7 +322,7 @@ void icount_start_warp_timer(void)
* to vCPU was processed in advance and vCPU went to sleep.
* Therefore we have to wake it up for doing someting.
*/
- if (replay_has_checkpoint()) {
+ if (replay_has_event()) {
qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
}
return;
@@ -404,6 +404,8 @@ void icount_account_warp_timer(void)
return;
}
+ replay_async_events();
+
/* warp clock deterministically in record/replay mode */
if (!replay_checkpoint(CHECKPOINT_CLOCK_WARP_ACCOUNT)) {
return;