xref: /openbmc/qemu/migration/migration.h (revision 3d9569b8)
1 /*
2  * QEMU live migration
3  *
4  * Copyright IBM, Corp. 2008
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.ibm.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  *
12  */
13 
14 #ifndef QEMU_MIGRATION_H
15 #define QEMU_MIGRATION_H
16 
17 #include "qapi/qapi-types-migration.h"
18 #include "qemu/thread.h"
19 #include "exec/cpu-common.h"
20 #include "qemu/coroutine_int.h"
21 #include "hw/qdev.h"
22 #include "io/channel.h"
23 #include "net/announce.h"
24 
25 struct PostcopyBlocktimeContext;
26 
27 #define  MIGRATION_RESUME_ACK_VALUE  (1)
28 
29 /* State for the incoming migration */
30 struct MigrationIncomingState {
31     QEMUFile *from_src_file;
32 
33     /*
34      * Free at the start of the main state load, set as the main thread finishes
35      * loading state.
36      */
37     QemuEvent main_thread_load_event;
38 
39     /* For network announces */
40     AnnounceTimer  announce_timer;
41 
42     size_t         largest_page_size;
43     bool           have_fault_thread;
44     QemuThread     fault_thread;
45     QemuSemaphore  fault_thread_sem;
46     /* Set this when we want the fault thread to quit */
47     bool           fault_thread_quit;
48 
49     bool           have_listen_thread;
50     QemuThread     listen_thread;
51     QemuSemaphore  listen_thread_sem;
52 
53     /* For the kernel to send us notifications */
54     int       userfault_fd;
55     /* To notify the fault_thread to wake, e.g., when need to quit */
56     int       userfault_event_fd;
57     QEMUFile *to_src_file;
58     QemuMutex rp_mutex;    /* We send replies from multiple threads */
59     /* RAMBlock of last request sent to source */
60     RAMBlock *last_rb;
61     void     *postcopy_tmp_page;
62     void     *postcopy_tmp_zero_page;
63     /* PostCopyFD's for external userfaultfds & handlers of shared memory */
64     GArray   *postcopy_remote_fds;
65 
66     QEMUBH *bh;
67 
68     int state;
69 
70     bool have_colo_incoming_thread;
71     QemuThread colo_incoming_thread;
72     /* The coroutine we should enter (back) after failover */
73     Coroutine *migration_incoming_co;
74     QemuSemaphore colo_incoming_sem;
75 
76     /*
77      * PostcopyBlocktimeContext to keep information for postcopy
78      * live migration, to calculate vCPU block time
79      * */
80     struct PostcopyBlocktimeContext *blocktime_ctx;
81 
82     /* notify PAUSED postcopy incoming migrations to try to continue */
83     bool postcopy_recover_triggered;
84     QemuSemaphore postcopy_pause_sem_dst;
85     QemuSemaphore postcopy_pause_sem_fault;
86 
87     /* List of listening socket addresses  */
88     SocketAddressList *socket_address_list;
89 };
90 
91 MigrationIncomingState *migration_incoming_get_current(void);
92 void migration_incoming_state_destroy(void);
93 /*
94  * Functions to work with blocktime context
95  */
96 void fill_destination_postcopy_migration_info(MigrationInfo *info);
97 
98 #define TYPE_MIGRATION "migration"
99 
100 #define MIGRATION_CLASS(klass) \
101     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
102 #define MIGRATION_OBJ(obj) \
103     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
104 #define MIGRATION_GET_CLASS(obj) \
105     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
106 
107 typedef struct MigrationClass {
108     /*< private >*/
109     DeviceClass parent_class;
110 } MigrationClass;
111 
112 struct MigrationState
113 {
114     /*< private >*/
115     DeviceState parent_obj;
116 
117     /*< public >*/
118     size_t bytes_xfer;
119     QemuThread thread;
120     QEMUBH *cleanup_bh;
121     QEMUFile *to_dst_file;
122     /*
123      * Protects to_dst_file pointer.  We need to make sure we won't
124      * yield or hang during the critical section, since this lock will
125      * be used in OOB command handler.
126      */
127     QemuMutex qemu_file_lock;
128 
129     /*
130      * Used to allow urgent requests to override rate limiting.
131      */
132     QemuSemaphore rate_limit_sem;
133 
134     /* pages already send at the beginning of current iteration */
135     uint64_t iteration_initial_pages;
136 
137     /* pages transferred per second */
138     double pages_per_second;
139 
140     /* bytes already send at the beginning of current iteration */
141     uint64_t iteration_initial_bytes;
142     /* time at the start of current iteration */
143     int64_t iteration_start_time;
144     /*
145      * The final stage happens when the remaining data is smaller than
146      * this threshold; it's calculated from the requested downtime and
147      * measured bandwidth
148      */
149     int64_t threshold_size;
150 
151     /* params from 'migrate-set-parameters' */
152     MigrationParameters parameters;
153 
154     int state;
155 
156     /* State related to return path */
157     struct {
158         QEMUFile     *from_dst_file;
159         QemuThread    rp_thread;
160         bool          error;
161         QemuSemaphore rp_sem;
162     } rp_state;
163 
164     double mbps;
165     /* Timestamp when recent migration starts (ms) */
166     int64_t start_time;
167     /* Total time used by latest migration (ms) */
168     int64_t total_time;
169     /* Timestamp when VM is down (ms) to migrate the last stuff */
170     int64_t downtime_start;
171     int64_t downtime;
172     int64_t expected_downtime;
173     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
174     int64_t setup_time;
175     /*
176      * Whether guest was running when we enter the completion stage.
177      * If migration is interrupted by any reason, we need to continue
178      * running the guest on source.
179      */
180     bool vm_was_running;
181 
182     /* Flag set once the migration has been asked to enter postcopy */
183     bool start_postcopy;
184     /* Flag set after postcopy has sent the device state */
185     bool postcopy_after_devices;
186 
187     /* Flag set once the migration thread is running (and needs joining) */
188     bool migration_thread_running;
189 
190     /* Flag set once the migration thread called bdrv_inactivate_all */
191     bool block_inactive;
192 
193     /* Migration is paused due to pause-before-switchover */
194     QemuSemaphore pause_sem;
195 
196     /* The semaphore is used to notify COLO thread that failover is finished */
197     QemuSemaphore colo_exit_sem;
198 
199     /* The semaphore is used to notify COLO thread to do checkpoint */
200     QemuSemaphore colo_checkpoint_sem;
201     int64_t colo_checkpoint_time;
202     QEMUTimer *colo_delay_timer;
203 
204     /* The first error that has occurred.
205        We used the mutex to be able to return the 1st error message */
206     Error *error;
207     /* mutex to protect errp */
208     QemuMutex error_mutex;
209 
210     /* Do we have to clean up -b/-i from old migrate parameters */
211     /* This feature is deprecated and will be removed */
212     bool must_remove_block_options;
213 
214     /*
215      * Global switch on whether we need to store the global state
216      * during migration.
217      */
218     bool store_global_state;
219 
220     /* Whether we send QEMU_VM_CONFIGURATION during migration */
221     bool send_configuration;
222     /* Whether we send section footer during migration */
223     bool send_section_footer;
224 
225     /* Needed by postcopy-pause state */
226     QemuSemaphore postcopy_pause_sem;
227     QemuSemaphore postcopy_pause_rp_sem;
228     /*
229      * Whether we abort the migration if decompression errors are
230      * detected at the destination. It is left at false for qemu
231      * older than 3.0, since only newer qemu sends streams that
232      * do not trigger spurious decompression errors.
233      */
234     bool decompress_error_check;
235 };
236 
237 void migrate_set_state(int *state, int old_state, int new_state);
238 
239 void migration_fd_process_incoming(QEMUFile *f);
240 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
241 void migration_incoming_process(void);
242 
243 bool  migration_has_all_channels(void);
244 
245 uint64_t migrate_max_downtime(void);
246 
247 void migrate_set_error(MigrationState *s, const Error *error);
248 void migrate_fd_error(MigrationState *s, const Error *error);
249 
250 void migrate_fd_connect(MigrationState *s, Error *error_in);
251 
252 bool migration_is_setup_or_active(int state);
253 
254 void migrate_init(MigrationState *s);
255 bool migration_is_blocked(Error **errp);
256 /* True if outgoing migration has entered postcopy phase */
257 bool migration_in_postcopy(void);
258 MigrationState *migrate_get_current(void);
259 
260 bool migrate_postcopy(void);
261 
262 bool migrate_release_ram(void);
263 bool migrate_postcopy_ram(void);
264 bool migrate_zero_blocks(void);
265 bool migrate_dirty_bitmaps(void);
266 bool migrate_ignore_shared(void);
267 
268 bool migrate_auto_converge(void);
269 bool migrate_use_multifd(void);
270 bool migrate_pause_before_switchover(void);
271 int migrate_multifd_channels(void);
272 
273 int migrate_use_xbzrle(void);
274 int64_t migrate_xbzrle_cache_size(void);
275 bool migrate_colo_enabled(void);
276 
277 bool migrate_use_block(void);
278 bool migrate_use_block_incremental(void);
279 int migrate_max_cpu_throttle(void);
280 bool migrate_use_return_path(void);
281 
282 uint64_t ram_get_total_transferred_pages(void);
283 
284 bool migrate_use_compression(void);
285 int migrate_compress_level(void);
286 int migrate_compress_threads(void);
287 int migrate_compress_wait_thread(void);
288 int migrate_decompress_threads(void);
289 bool migrate_use_events(void);
290 bool migrate_postcopy_blocktime(void);
291 
292 /* Sending on the return path - generic and then for each message type */
293 void migrate_send_rp_shut(MigrationIncomingState *mis,
294                           uint32_t value);
295 void migrate_send_rp_pong(MigrationIncomingState *mis,
296                           uint32_t value);
297 int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
298                               ram_addr_t start, size_t len);
299 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
300                                  char *block_name);
301 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
302 
303 void dirty_bitmap_mig_before_vm_start(void);
304 void init_dirty_bitmap_incoming_migration(void);
305 void migrate_add_address(SocketAddress *address);
306 
307 int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque);
308 
309 #define qemu_ram_foreach_block \
310   #warning "Use foreach_not_ignored_block in migration code"
311 
312 void migration_make_urgent_request(void);
313 void migration_consume_urgent_request(void);
314 
315 #endif
316