replay: assert time only goes forward

If we find ourselves trying to add an event to the log where time has
gone backwards it is because a vCPU event has occurred and the
main-loop is not yet aware of time moving forward. This should not
happen and if it does its better to fail early than generate a log
that will have weird behaviour.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
This commit is contained in:
Alex Bennée 2017-04-05 11:05:28 +01:00
parent 1d05906b95
commit 982263ce71
2 changed files with 8 additions and 0 deletions

View file

@ -195,6 +195,10 @@ void replay_save_instructions(void)
if (replay_file && replay_mode == REPLAY_MODE_RECORD) {
replay_mutex_lock();
int diff = (int)(replay_get_current_step() - replay_state.current_step);
/* Time can only go forward */
assert(diff >= 0);
if (diff > 0) {
replay_put_event(EVENT_INSTRUCTION);
replay_put_dword(diff);

View file

@ -84,6 +84,10 @@ void replay_account_executed_instructions(void)
if (replay_state.instructions_count > 0) {
int count = (int)(replay_get_current_step()
- replay_state.current_step);
/* Time can only go forward */
assert(count >= 0);
replay_state.instructions_count -= count;
replay_state.current_step += count;
if (replay_state.instructions_count == 0) {