1 /* 2 * replay-snapshot.c 3 * 4 * Copyright (c) 2010-2016 Institute for System Programming 5 * of the Russian Academy of Sciences. 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2 or later. 8 * See the COPYING file in the top-level directory. 9 * 10 */ 11 12 #include "qemu/osdep.h" 13 #include "qapi/error.h" 14 #include "sysemu/replay.h" 15 #include "replay-internal.h" 16 #include "monitor/monitor.h" 17 #include "qapi/qmp/qstring.h" 18 #include "qemu/error-report.h" 19 #include "migration/vmstate.h" 20 #include "migration/snapshot.h" 21 22 static int replay_pre_save(void *opaque) 23 { 24 ReplayState *state = opaque; 25 state->file_offset = ftell(replay_file); 26 27 return 0; 28 } 29 30 static int replay_post_load(void *opaque, int version_id) 31 { 32 ReplayState *state = opaque; 33 if (replay_mode == REPLAY_MODE_PLAY) { 34 fseek(replay_file, state->file_offset, SEEK_SET); 35 /* If this was a vmstate, saved in recording mode, 36 we need to initialize replay data fields. */ 37 replay_fetch_data_kind(); 38 } else if (replay_mode == REPLAY_MODE_RECORD) { 39 /* This is only useful for loading the initial state. 40 Therefore reset all the counters. */ 41 state->instruction_count = 0; 42 state->block_request_id = 0; 43 } 44 45 return 0; 46 } 47 48 static const VMStateDescription vmstate_replay = { 49 .name = "replay", 50 .version_id = 2, 51 .minimum_version_id = 2, 52 .pre_save = replay_pre_save, 53 .post_load = replay_post_load, 54 .fields = (const VMStateField[]) { 55 VMSTATE_INT64_ARRAY(cached_clock, ReplayState, REPLAY_CLOCK_COUNT), 56 VMSTATE_UINT64(current_icount, ReplayState), 57 VMSTATE_INT32(instruction_count, ReplayState), 58 VMSTATE_UINT32(data_kind, ReplayState), 59 VMSTATE_UINT32(has_unread_data, ReplayState), 60 VMSTATE_UINT64(file_offset, ReplayState), 61 VMSTATE_UINT64(block_request_id, ReplayState), 62 VMSTATE_UINT64(read_event_id, ReplayState), 63 VMSTATE_END_OF_LIST() 64 }, 65 }; 66 67 void replay_vmstate_register(void) 68 { 69 vmstate_register(NULL, 0, &vmstate_replay, &replay_state); 70 } 71 72 void replay_vmstate_init(void) 73 { 74 Error *err = NULL; 75 76 if (replay_snapshot) { 77 if (replay_mode == REPLAY_MODE_RECORD) { 78 if (!save_snapshot(replay_snapshot, 79 true, NULL, false, NULL, &err)) { 80 error_report_err(err); 81 error_report("Could not create snapshot for icount record"); 82 exit(1); 83 } 84 } else if (replay_mode == REPLAY_MODE_PLAY) { 85 if (!load_snapshot(replay_snapshot, NULL, false, NULL, &err)) { 86 error_report_err(err); 87 error_report("Could not load snapshot for icount replay"); 88 exit(1); 89 } 90 } 91 } 92 } 93 94 bool replay_can_snapshot(void) 95 { 96 return replay_mode == REPLAY_MODE_NONE 97 || !replay_has_events(); 98 } 99