include/sysemu/replay.h

   1 #ifndef REPLAY_H
   2 #define REPLAY_H
   3
   4 /*
   5  * replay.h
   6  *
   7  * Copyright (c) 2010-2015 Institute for System Programming
   8  *                         of the Russian Academy of Sciences.
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  11  * See the COPYING file in the top-level directory.
  12  *
  13  */
  14
  15 #include "qapi/qapi-types-misc.h"
  16 #include "qapi/qapi-types-run-state.h"
  17 #include "qapi/qapi-types-replay.h"
  18 #include "qapi/qapi-types-ui.h"
  19 #include "block/aio.h"
  20
  21 /* replay clock kinds */
  22 enum ReplayClockKind {
  23     /* host_clock */
  24     REPLAY_CLOCK_HOST,
  25     /* virtual_rt_clock */
  26     REPLAY_CLOCK_VIRTUAL_RT,
  27     REPLAY_CLOCK_COUNT
  28 };
  29 typedef enum ReplayClockKind ReplayClockKind;
  30
  31 /* IDs of the checkpoints */
  32 enum ReplayCheckpoint {
  33     CHECKPOINT_CLOCK_WARP_START,
  34     CHECKPOINT_CLOCK_WARP_ACCOUNT,
  35     CHECKPOINT_RESET_REQUESTED,
  36     CHECKPOINT_SUSPEND_REQUESTED,
  37     CHECKPOINT_CLOCK_VIRTUAL,
  38     CHECKPOINT_CLOCK_HOST,
  39     CHECKPOINT_CLOCK_VIRTUAL_RT,
  40     CHECKPOINT_INIT,
  41     CHECKPOINT_RESET,
  42     CHECKPOINT_COUNT
  43 };
  44 typedef enum ReplayCheckpoint ReplayCheckpoint;
  45
  46 typedef struct ReplayNetState ReplayNetState;
  47
  48 extern ReplayMode replay_mode;
  49
  50 /* Name of the initial VM snapshot */
  51 extern char *replay_snapshot;
  52
  53 /* Replay locking
  54  *
  55  * The locks are needed to protect the shared structures and log file
  56  * when doing record/replay. They also are the main sync-point between
  57  * the main-loop thread and the vCPU thread. This was a role
  58  * previously filled by the BQL which has been busy trying to reduce
  59  * its impact across the code. This ensures blocks of events stay
  60  * sequential and reproducible.
  61  */
  62
  63 void replay_mutex_lock(void);
  64 void replay_mutex_unlock(void);
  65
  66 /* Replay process control functions */
  67
  68 /*! Enables recording or saving event log with specified parameters */
  69 void replay_configure(struct QemuOpts *opts);
  70 /*! Initializes timers used for snapshotting and enables events recording */
  71 void replay_start(void);
  72 /*! Closes replay log file and frees other resources. */
  73 void replay_finish(void);
  74 /*! Adds replay blocker with the specified error description */
  75 void replay_add_blocker(Error *reason);
  76 /* Returns name of the replay log file */
  77 const char *replay_get_filename(void);
  78 /*
  79  * Start making one step in backward direction.
  80  * Used by gdbstub for backwards debugging.
  81  * Returns true on success.
  82  */
  83 bool replay_reverse_step(void);
  84 /*
  85  * Start searching the last breakpoint/watchpoint.
  86  * Used by gdbstub for backwards debugging.
  87  * Returns true if the process successfully started.
  88  */
  89 bool replay_reverse_continue(void);
  90 /*
  91  * Returns true if replay module is processing
  92  * reverse_continue or reverse_step request
  93  */
  94 bool replay_running_debug(void);
  95 /* Called in reverse debugging mode to collect breakpoint information */
  96 void replay_breakpoint(void);
  97 /* Called when gdb is attached to gdbstub */
  98 void replay_gdb_attached(void);
  99
 100 /* Processing the instructions */
 101
 102 /*! Returns number of executed instructions. */
 103 uint64_t replay_get_current_icount(void);
 104 /*! Returns number of instructions to execute in replay mode. */
 105 int replay_get_instructions(void);
 106 /*! Updates instructions counter in replay mode. */
 107 void replay_account_executed_instructions(void);
 108
 109 /* Interrupts and exceptions */
 110
 111 /*! Called by exception handler to write or read
 112     exception processing events. */
 113 bool replay_exception(void);
 114 /*! Used to determine that exception is pending.
 115     Does not proceed to the next event in the log. */
 116 bool replay_has_exception(void);
 117 /*! Called by interrupt handlers to write or read
 118     interrupt processing events.
 119     \return true if interrupt should be processed */
 120 bool replay_interrupt(void);
 121 /*! Tries to read interrupt event from the file.
 122     Returns true, when interrupt request is pending */
 123 bool replay_has_interrupt(void);
 124
 125 /* Processing clocks and other time sources */
 126
 127 /*! Save the specified clock */
 128 int64_t replay_save_clock(ReplayClockKind kind, int64_t clock,
 129                           int64_t raw_icount);
 130 /*! Read the specified clock from the log or return cached data */
 131 int64_t replay_read_clock(ReplayClockKind kind, int64_t raw_icount);
 132 /*! Saves or reads the clock depending on the current replay mode. */
 133 #define REPLAY_CLOCK(clock, value)                                      \
 134     (replay_mode == REPLAY_MODE_PLAY                                    \
 135         ? replay_read_clock((clock), icount_get_raw())                  \
 136         : replay_mode == REPLAY_MODE_RECORD                             \
 137             ? replay_save_clock((clock), (value), icount_get_raw())     \
 138             : (value))
 139 #define REPLAY_CLOCK_LOCKED(clock, value)                               \
 140     (replay_mode == REPLAY_MODE_PLAY                                    \
 141         ? replay_read_clock((clock), icount_get_raw_locked())           \
 142         : replay_mode == REPLAY_MODE_RECORD                             \
 143             ? replay_save_clock((clock), (value), icount_get_raw_locked()) \
 144             : (value))
 145
 146 /* Processing data from random generators */
 147
 148 /* Saves the values from the random number generator */
 149 void replay_save_random(int ret, void *buf, size_t len);
 150 /* Loads the saved values for the random number generator */
 151 int replay_read_random(void *buf, size_t len);
 152
 153 /* Events */
 154
 155 /*! Called when qemu shutdown is requested. */
 156 void replay_shutdown_request(ShutdownCause cause);
 157 /*! Should be called at check points in the execution.
 158     These check points are skipped, if they were not met.
 159     Saves checkpoint in the SAVE mode and validates in the PLAY mode.
 160     Returns 0 in PLAY mode if checkpoint was not found.
 161     Returns 1 in all other cases. */
 162 bool replay_checkpoint(ReplayCheckpoint checkpoint);
 163 /*! Used to determine that checkpoint or async event is pending.
 164     Does not proceed to the next event in the log. */
 165 bool replay_has_event(void);
 166 /*
 167  * Processes the async events added to the queue (while recording)
 168  * or reads the events from the file (while replaying).
 169  */
 170 void replay_async_events(void);
 171
 172 /* Asynchronous events queue */
 173
 174 /*! Disables storing events in the queue */
 175 void replay_disable_events(void);
 176 /*! Enables storing events in the queue */
 177 void replay_enable_events(void);
 178 /*! Returns true when saving events is enabled */
 179 bool replay_events_enabled(void);
 180 /* Flushes events queue */
 181 void replay_flush_events(void);
 182 /*! Adds bottom half event to the queue */
 183 void replay_bh_schedule_event(QEMUBH *bh);
 184 /* Adds oneshot bottom half event to the queue */
 185 void replay_bh_schedule_oneshot_event(AioContext *ctx,
 186     QEMUBHFunc *cb, void *opaque);
 187 /*! Adds input event to the queue */
 188 void replay_input_event(QemuConsole *src, InputEvent *evt);
 189 /*! Adds input sync event to the queue */
 190 void replay_input_sync_event(void);
 191 /*! Adds block layer event to the queue */
 192 void replay_block_event(QEMUBH *bh, uint64_t id);
 193 /*! Returns ID for the next block event */
 194 uint64_t blkreplay_next_id(void);
 195
 196 /* Character device */
 197
 198 /*! Registers char driver to save it's events */
 199 void replay_register_char_driver(struct Chardev *chr);
 200 /*! Saves write to char device event to the log */
 201 void replay_chr_be_write(struct Chardev *s, const uint8_t *buf, int len);
 202 /*! Writes char write return value to the replay log. */
 203 void replay_char_write_event_save(int res, int offset);
 204 /*! Reads char write return value from the replay log. */
 205 void replay_char_write_event_load(int *res, int *offset);
 206 /*! Reads information about read_all character event. */
 207 int replay_char_read_all_load(uint8_t *buf);
 208 /*! Writes character read_all error code into the replay log. */
 209 void replay_char_read_all_save_error(int res);
 210 /*! Writes character read_all execution result into the replay log. */
 211 void replay_char_read_all_save_buf(uint8_t *buf, int offset);
 212
 213 /* Network */
 214
 215 /*! Registers replay network filter attached to some backend. */
 216 ReplayNetState *replay_register_net(NetFilterState *nfs);
 217 /*! Unregisters replay network filter. */
 218 void replay_unregister_net(ReplayNetState *rns);
 219 /*! Called to write network packet to the replay log. */
 220 void replay_net_packet_event(ReplayNetState *rns, unsigned flags,
 221                              const struct iovec *iov, int iovcnt);
 222
 223 /* Audio */
 224
 225 /*! Saves/restores number of played samples of audio out operation. */
 226 void replay_audio_out(size_t *played);
 227 /*! Saves/restores recorded samples of audio in operation. */
 228 void replay_audio_in(size_t *recorded, void *samples, size_t *wpos, size_t size);
 229
 230 /* VM state operations */
 231
 232 /*! Called at the start of execution.
 233     Loads or saves initial vmstate depending on execution mode. */
 234 void replay_vmstate_init(void);
 235 /*! Called to ensure that replay state is consistent and VM snapshot
 236     can be created */
 237 bool replay_can_snapshot(void);
 238
 239 #endif