From 1f881ea4a444ef36a8b6907b0b82be4b3af253a2 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Alex=20Benn=C3=A9e?= Date: Mon, 11 Dec 2023 09:13:40 +0000 Subject: [PATCH] replay: stop us hanging in rr_wait_io_event MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit A lot of the hang I see are when we end up spinning in rr_wait_io_event for an event that will never come in playback. As a new check functions which can see if we are in PLAY mode and kick us us the wait function so the event can be processed. This fixes most of the failures in replay_kernel.py Fixes: https://gitlab.com/qemu-project/qemu/-/issues/2013 Cc: Pavel Dovgalyuk Reviewed-by: Richard Henderson Signed-off-by: Alex Bennée Message-Id: <20231211091346.14616-12-alex.bennee@linaro.org> --- accel/tcg/tcg-accel-ops-rr.c | 2 +- include/sysemu/replay.h | 5 +++++ replay/replay.c | 21 +++++++++++++++++++++ 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c index 611932f3c3..825e35b3dc 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()) { + while (all_cpu_threads_idle() && replay_can_wait()) { rr_stop_kick_timer(); qemu_cond_wait_iothread(first_cpu->halt_cond); } diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index 08aae5869f..83995ae4bd 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -70,6 +70,11 @@ 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/replay/replay.c b/replay/replay.c index ff197f436b..3fd241a4fc 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -449,6 +449,27 @@ 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) { -- 2.39.2