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author | Alex Bennée <alex.bennee@linaro.org> | 2017-04-05 11:05:28 +0100 |
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committer | Alex Bennée <alex.bennee@linaro.org> | 2017-04-10 10:23:38 +0100 |
commit | 982263ce714ffcc4c7c41a7b255bd29e093912fe (patch) | |
tree | 9c4b07a878d3d32e0a23a6653ef92c260cb61b90 | |
parent | 1d05906b95e7f2a35be2392506f9af8f89ff39a5 (diff) | |
download | qemu-982263ce714ffcc4c7c41a7b255bd29e093912fe.zip qemu-982263ce714ffcc4c7c41a7b255bd29e093912fe.tar.gz qemu-982263ce714ffcc4c7c41a7b255bd29e093912fe.tar.bz2 |
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>
-rw-r--r-- | replay/replay-internal.c | 4 | ||||
-rw-r--r-- | replay/replay.c | 4 |
2 files changed, 8 insertions, 0 deletions
diff --git a/replay/replay-internal.c b/replay/replay-internal.c index bea7b4a..fca8514 100644 --- a/replay/replay-internal.c +++ b/replay/replay-internal.c @@ -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); diff --git a/replay/replay.c b/replay/replay.c index 9e0724e..f810628 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -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) { |