| Message ID | 20240318154621.2361161-6-npiggin@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | replay: fixes and new test cases | expand |
Nicholas Piggin <npiggin@gmail.com> writes: > This reverts commit 1f881ea4a444ef36a8b6907b0b82be4b3af253a2. > > That commit causes reverse_debugging.py test failures, and does > not seem to solve the root cause of the problem x86-64 still > hangs in record/replay tests. > > The problem with short-cutting the iowait that was taken during > record phase is that related events will not get consumed at the > same points (e.g., reading the clock). > > A hang with zero icount always seems to be a symptom of an earlier > problem that has caused the recording to become out of synch with > the execution and consumption of events by replay. > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Alex Bennée <alex.bennee@linaro.org>
diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index f229b2109c..8102fa54f0 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -73,11 +73,6 @@ int replay_get_instructions(void); /*! Updates instructions counter in replay mode. */ void replay_account_executed_instructions(void); -/** - * replay_can_wait: check if we should pause for wait-io - */ -bool replay_can_wait(void); - /* Processing clocks and other time sources */ /*! Save the specified clock */ diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c index 894e73e52c..a942442a33 100644 --- a/accel/tcg/tcg-accel-ops-rr.c +++ b/accel/tcg/tcg-accel-ops-rr.c @@ -109,7 +109,7 @@ static void rr_wait_io_event(void) { CPUState *cpu; - while (all_cpu_threads_idle() && replay_can_wait()) { + while (all_cpu_threads_idle()) { rr_stop_kick_timer(); qemu_cond_wait_bql(first_cpu->halt_cond); } diff --git a/replay/replay.c b/replay/replay.c index b8564a4813..895fa6b67a 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -451,27 +451,6 @@ void replay_start(void) replay_enable_events(); } -/* - * For none/record the answer is yes. - */ -bool replay_can_wait(void) -{ - if (replay_mode == REPLAY_MODE_PLAY) { - /* - * For playback we shouldn't ever be at a point we wait. If - * the instruction count has reached zero and we have an - * unconsumed event we should go around again and consume it. - */ - if (replay_state.instruction_count == 0 && replay_state.has_unread_data) { - return false; - } else { - replay_sync_error("Playback shouldn't have to iowait"); - } - } - return true; -} - - void replay_finish(void) { if (replay_mode == REPLAY_MODE_NONE) {
This reverts commit 1f881ea4a444ef36a8b6907b0b82be4b3af253a2. That commit causes reverse_debugging.py test failures, and does not seem to solve the root cause of the problem x86-64 still hangs in record/replay tests. The problem with short-cutting the iowait that was taken during record phase is that related events will not get consumed at the same points (e.g., reading the clock). A hang with zero icount always seems to be a symptom of an earlier problem that has caused the recording to become out of synch with the execution and consumption of events by replay. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- include/sysemu/replay.h | 5 ----- accel/tcg/tcg-accel-ops-rr.c | 2 +- replay/replay.c | 21 --------------------- 3 files changed, 1 insertion(+), 27 deletions(-)