This patch introduces checkpoints that synchronize cpu thread and iothread.
When checkpoint is met in the code all asynchronous events from the queue
are executed.
Signed-off-by: Pavel Dovgalyuk <pavel.dovga...@ispras.ru>
---
block.c | 11 +++++++++++
cpus.c | 7 ++++++-
include/qemu/timer.h | 6 ++++--
main-loop.c | 5 +++++
qemu-timer.c | 46 ++++++++++++++++++++++++++++++++++++++--------
replay/replay-internal.h | 3 +++
replay/replay.c | 28 ++++++++++++++++++++++++++++
replay/replay.h | 6 ++++++
stubs/replay.c | 11 +++++++++++
vl.c | 3 ++-
10 files changed, 114 insertions(+), 12 deletions(-)
diff --git a/block.c b/block.c
index a612594..88626c4 100644
--- a/block.c
+++ b/block.c
@@ -1951,6 +1951,11 @@ void bdrv_drain_all(void)
BlockDriverState *bs;
while (busy) {
+ if (!replay_checkpoint(8)) {
+ /* Do not wait anymore, we stopped at some place in
+ the middle of execution during replay */
+ return;
+ }
busy = false;
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
@@ -1961,6 +1966,12 @@ void bdrv_drain_all(void)
aio_context_release(aio_context);
}
}
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ /* Skip checkpoints from the log */
+ while (replay_checkpoint(8)) {
+ /* Nothing */
+ }
+ }
}
/* make a BlockDriverState anonymous by removing from bdrv_state and
diff --git a/cpus.c b/cpus.c
index 82efbfc..2f038ef 100644
--- a/cpus.c
+++ b/cpus.c
@@ -389,7 +389,7 @@ void qtest_clock_warp(int64_t dest)
timers_state.qemu_icount_bias += warp;
seqlock_write_unlock(&timers_state.vm_clock_seqlock);
- qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
+ qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL, false);
clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
}
qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
@@ -409,6 +409,11 @@ void qemu_clock_warp(QEMUClockType type)
return;
}
+ /* warp clock deterministically in record/replay mode */
+ if (!replay_checkpoint(4)) {
+ return;
+ }
+
/*
* If the CPUs have been sleeping, advance QEMU_CLOCK_VIRTUAL timer now.
* This ensures that the deadline for the timer is computed correctly
below.
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index f2e66bf..7b46f83 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -239,13 +239,14 @@ void qemu_clock_unregister_reset_notifier(QEMUClockType
type,
/**
* qemu_clock_run_timers:
* @type: clock on which to operate
+ * @run_all: true, when called from qemu_clock_run_all_timers
*
* Run all the timers associated with the default timer list
* of a clock.
*
* Returns: true if any timer ran.
*/
-bool qemu_clock_run_timers(QEMUClockType type);
+bool qemu_clock_run_timers(QEMUClockType type, bool run_all);
/**
* qemu_clock_run_all_timers:
@@ -336,12 +337,13 @@ QEMUClockType timerlist_get_clock(QEMUTimerList
*timer_list);
/**
* timerlist_run_timers:
* @timer_list: the timer list to use
+ * @run_all: true, when called from qemu_clock_run_all_timers
*
* Call all expired timers associated with the timer list.
*
* Returns: true if any timer expired
*/
-bool timerlist_run_timers(QEMUTimerList *timer_list);
+bool timerlist_run_timers(QEMUTimerList *timer_list, bool run_all);
/**
* timerlist_notify:
diff --git a/main-loop.c b/main-loop.c
index 981bcb5..d6e93c3 100644
--- a/main-loop.c
+++ b/main-loop.c
@@ -497,6 +497,11 @@ int main_loop_wait(int nonblocking)
slirp_pollfds_poll(gpollfds, (ret < 0));
#endif
+ /* CPU thread can infinitely wait for event after
+ missing the warp */
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ qemu_clock_warp(QEMU_CLOCK_VIRTUAL);
+ }
qemu_clock_run_all_timers();
return ret;
diff --git a/qemu-timer.c b/qemu-timer.c
index 25c086c..60194a6 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -458,7 +458,7 @@ bool timer_expired(QEMUTimer *timer_head, int64_t
current_time)
return timer_expired_ns(timer_head, current_time * timer_head->scale);
}
-bool timerlist_run_timers(QEMUTimerList *timer_list)
+bool timerlist_run_timers(QEMUTimerList *timer_list, bool run_all)
{
QEMUTimer *ts;
int64_t current_time;
@@ -466,6 +466,29 @@ bool timerlist_run_timers(QEMUTimerList *timer_list)
QEMUTimerCB *cb;
void *opaque;
+ switch (timer_list->clock->type) {
+ case QEMU_CLOCK_REALTIME:
+ break;
+ default:
+ case QEMU_CLOCK_VIRTUAL:
+ if ((replay_mode != REPLAY_MODE_NONE && !runstate_is_running())
+ || !replay_checkpoint(run_all ? 2 : 3)) {
+ return false;
+ }
+ break;
+ case QEMU_CLOCK_HOST:
+ if ((replay_mode != REPLAY_MODE_NONE && !runstate_is_running())
+ || !replay_checkpoint(run_all ? 5 : 6)) {
+ return false;
+ }
+ case QEMU_CLOCK_VIRTUAL_RT:
+ if ((replay_mode != REPLAY_MODE_NONE && !runstate_is_running())
+ || !replay_checkpoint(run_all ? 10 : 11)) {
+ return false;
+ }
+ break;
+ }
+
qemu_event_reset(&timer_list->timers_done_ev);
if (!timer_list->clock->enabled) {
goto out;
@@ -498,9 +521,9 @@ out:
return progress;
}
-bool qemu_clock_run_timers(QEMUClockType type)
+bool qemu_clock_run_timers(QEMUClockType type, bool run_all)
{
- return timerlist_run_timers(main_loop_tlg.tl[type]);
+ return timerlist_run_timers(main_loop_tlg.tl[type], run_all);
}
void timerlistgroup_init(QEMUTimerListGroup *tlg,
@@ -525,7 +548,7 @@ bool timerlistgroup_run_timers(QEMUTimerListGroup *tlg)
QEMUClockType type;
bool progress = false;
for (type = 0; type < QEMU_CLOCK_MAX; type++) {
- progress |= timerlist_run_timers(tlg->tl[type]);
+ progress |= timerlist_run_timers(tlg->tl[type], false);
}
return progress;
}
@@ -534,11 +557,18 @@ int64_t timerlistgroup_deadline_ns(QEMUTimerListGroup
*tlg)
{
int64_t deadline = -1;
QEMUClockType type;
+ bool play = replay_mode == REPLAY_MODE_PLAY;
for (type = 0; type < QEMU_CLOCK_MAX; type++) {
if (qemu_clock_use_for_deadline(tlg->tl[type]->clock->type)) {
- deadline = qemu_soonest_timeout(deadline,
- timerlist_deadline_ns(
- tlg->tl[type]));
+ if (!play || tlg->tl[type]->clock->type == QEMU_CLOCK_REALTIME) {
+ deadline = qemu_soonest_timeout(deadline,
+ timerlist_deadline_ns(
+ tlg->tl[type]));
+ } else {
+ /* Read clock from the replay file and
+ do not calculate the deadline, based on virtual clock. */
+ qemu_clock_get_ns(tlg->tl[type]->clock->type);
+ }
}
}
return deadline;
@@ -608,7 +638,7 @@ bool qemu_clock_run_all_timers(void)
QEMUClockType type;
for (type = 0; type < QEMU_CLOCK_MAX; type++) {
- progress |= qemu_clock_run_timers(type);
+ progress |= qemu_clock_run_timers(type, true);
}
return progress;
diff --git a/replay/replay-internal.h b/replay/replay-internal.h
index ec6973d..5dad566 100755
--- a/replay/replay-internal.h
+++ b/replay/replay-internal.h
@@ -32,6 +32,9 @@
#define EVENT_CLOCK 64
/* some of grteater codes are reserved for clocks */
+/* for checkpoint event */
+#define EVENT_CHECKPOINT 96
+
/* Asynchronous events IDs */
#define REPLAY_ASYNC_COUNT 0
diff --git a/replay/replay.c b/replay/replay.c
index 213f534..ebb7562 100755
--- a/replay/replay.c
+++ b/replay/replay.c
@@ -157,3 +157,31 @@ void replay_shutdown_request(void)
replay_put_event(EVENT_SHUTDOWN);
}
}
+
+/* Used checkpoints: 2 3 4 5 6 7 8 9 10 11 */
+int replay_checkpoint(unsigned int checkpoint)
+{
+ replay_save_instructions();
+
+ if (replay_file) {
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ if (!skip_async_events(EVENT_CHECKPOINT + checkpoint)) {
+ if (replay_data_kind == EVENT_ASYNC_OPT) {
+ replay_read_events(checkpoint);
+ replay_fetch_data_kind();
+ return replay_data_kind != EVENT_ASYNC_OPT;
+ }
+ return 0;
+ }
+ replay_has_unread_data = 0;
+ replay_read_events(checkpoint);
+ replay_fetch_data_kind();
+ return replay_data_kind != EVENT_ASYNC_OPT;
+ } else if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_put_event(EVENT_CHECKPOINT + checkpoint);
+ replay_save_events(checkpoint);
+ }
+ }
+
+ return 1;
+}
diff --git a/replay/replay.h b/replay/replay.h
index 00c9906..6961751 100755
--- a/replay/replay.h
+++ b/replay/replay.h
@@ -82,6 +82,12 @@ void replay_read_tm(struct tm *tm);
/*! Called when qemu shutdown is requested. */
void replay_shutdown_request(void);
+/*! Should be called at check points in the execution.
+ These check points are skipped, if they were not met.
+ Saves checkpoint in the SAVE mode and validates in the PLAY mode.
+ Returns 0 in PLAY mode if checkpoint was not found.
+ Returns 1 in all other cases. */
+int replay_checkpoint(unsigned int checkpoint);
/* Asynchronous events queue */
diff --git a/stubs/replay.c b/stubs/replay.c
index 397d4f2..3bb2d90 100755
--- a/stubs/replay.c
+++ b/stubs/replay.c
@@ -1,4 +1,5 @@
#include "replay/replay.h"
+#include "sysemu/sysemu.h"
ReplayMode replay_mode;
@@ -15,3 +16,13 @@ int64_t replay_read_clock(unsigned int kind)
{
return 0;
}
+
+int replay_checkpoint(unsigned int checkpoint)
+{
+ return 0;
+}
+
+int runstate_is_running(void)
+{
+ return 0;
+}
diff --git a/vl.c b/vl.c
index 171a198..4ef47a3 100644
--- a/vl.c
+++ b/vl.c
@@ -1857,7 +1857,8 @@ static bool main_loop_should_exit(void)
return true;
}
}
- if (qemu_reset_requested()) {
+ if (qemu_reset_requested_get() && replay_checkpoint(7)) {
+ qemu_reset_requested();
pause_all_vcpus();
cpu_synchronize_all_states();
qemu_system_reset(VMRESET_REPORT);
