From 89e46eb477113550485bc24264d249de9fd1260a Mon Sep 17 00:00:00 2001 From: Pavel Dovgalyuk Date: Tue, 27 Feb 2018 12:53:16 +0300 Subject: replay: don't process async events when warping the clock Virtual clock is warped from iothread and vcpu thread. When the hardware events associated with warp checkpoint, then interrupt delivering may be non-deterministic if checkpoint is processed in different threads in record and replay. This patch disables event processing for clock warp checkpoint and leaves all hardware events to other checkpoints (e.g., virtual clock). Signed-off-by: Pavel Dovgalyuk Message-Id: <20180227095316.1060.4134.stgit@pasha-VirtualBox> Signed-off-by: Paolo Bonzini Signed-off-by: Pavel Dovgalyuk --- replay/replay-events.c | 1 + replay/replay.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) (limited to 'replay') diff --git a/replay/replay-events.c b/replay/replay-events.c index 54dd9d2606..3d5fc8a479 100644 --- a/replay/replay-events.c +++ b/replay/replay-events.c @@ -205,6 +205,7 @@ static void replay_save_event(Event *event, int checkpoint) void replay_save_events(int checkpoint) { g_assert(replay_mutex_locked()); + g_assert(checkpoint != CHECKPOINT_CLOCK_WARP_START); while (!QTAILQ_EMPTY(&events_list)) { Event *event = QTAILQ_FIRST(&events_list); replay_save_event(event, checkpoint); diff --git a/replay/replay.c b/replay/replay.c index eae8daf18a..8228261401 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -211,7 +211,12 @@ bool replay_checkpoint(ReplayCheckpoint checkpoint) } else if (replay_mode == REPLAY_MODE_RECORD) { g_assert(replay_mutex_locked()); replay_put_event(EVENT_CHECKPOINT + checkpoint); - replay_save_events(checkpoint); + /* This checkpoint belongs to several threads. + Processing events from different threads is + non-deterministic */ + if (checkpoint != CHECKPOINT_CLOCK_WARP_START) { + replay_save_events(checkpoint); + } res = true; } out: -- cgit v1.2.1