qemu/replay/replay-snapshot.c
Pavel Dovgalyuk bb3d7702e8 replay: allow loading any snapshots before recording
This patch enables using -loadvm in recording mode to allow starting
the execution recording from any of the available snapshots.
It also fixes loading of the record/replay state, therefore snapshots
created in replay mode may also be used for starting the new recording.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Message-Id: <20180912081939.3228.56131.stgit@pasha-VirtualBox>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:08:58 +02:00

104 lines
3.1 KiB
C

/*
* replay-snapshot.c
*
* Copyright (c) 2010-2016 Institute for System Programming
* of the Russian Academy of Sciences.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "sysemu/replay.h"
#include "replay-internal.h"
#include "sysemu/sysemu.h"
#include "monitor/monitor.h"
#include "qapi/qmp/qstring.h"
#include "qemu/error-report.h"
#include "migration/vmstate.h"
#include "migration/snapshot.h"
static int replay_pre_save(void *opaque)
{
ReplayState *state = opaque;
state->file_offset = ftell(replay_file);
state->host_clock_last = qemu_clock_get_last(QEMU_CLOCK_HOST);
return 0;
}
static int replay_post_load(void *opaque, int version_id)
{
ReplayState *state = opaque;
if (replay_mode == REPLAY_MODE_PLAY) {
fseek(replay_file, state->file_offset, SEEK_SET);
qemu_clock_set_last(QEMU_CLOCK_HOST, state->host_clock_last);
/* If this was a vmstate, saved in recording mode,
we need to initialize replay data fields. */
replay_fetch_data_kind();
} else if (replay_mode == REPLAY_MODE_RECORD) {
/* This is only useful for loading the initial state.
Therefore reset all the counters. */
state->instructions_count = 0;
state->block_request_id = 0;
}
return 0;
}
static const VMStateDescription vmstate_replay = {
.name = "replay",
.version_id = 1,
.minimum_version_id = 1,
.pre_save = replay_pre_save,
.post_load = replay_post_load,
.fields = (VMStateField[]) {
VMSTATE_INT64_ARRAY(cached_clock, ReplayState, REPLAY_CLOCK_COUNT),
VMSTATE_UINT64(current_step, ReplayState),
VMSTATE_INT32(instructions_count, ReplayState),
VMSTATE_UINT32(data_kind, ReplayState),
VMSTATE_UINT32(has_unread_data, ReplayState),
VMSTATE_UINT64(file_offset, ReplayState),
VMSTATE_UINT64(block_request_id, ReplayState),
VMSTATE_UINT64(host_clock_last, ReplayState),
VMSTATE_INT32(read_event_kind, ReplayState),
VMSTATE_UINT64(read_event_id, ReplayState),
VMSTATE_INT32(read_event_checkpoint, ReplayState),
VMSTATE_END_OF_LIST()
},
};
void replay_vmstate_register(void)
{
vmstate_register(NULL, 0, &vmstate_replay, &replay_state);
}
void replay_vmstate_init(void)
{
Error *err = NULL;
if (replay_snapshot) {
if (replay_mode == REPLAY_MODE_RECORD) {
if (save_snapshot(replay_snapshot, &err) != 0) {
error_report_err(err);
error_report("Could not create snapshot for icount record");
exit(1);
}
} else if (replay_mode == REPLAY_MODE_PLAY) {
if (load_snapshot(replay_snapshot, &err) != 0) {
error_report_err(err);
error_report("Could not load snapshot for icount replay");
exit(1);
}
}
}
}
bool replay_can_snapshot(void)
{
return replay_mode == REPLAY_MODE_NONE
|| !replay_has_events();
}