Merge remote-tracking branch 'remotes/ehabkost-gl/tags/x86-next-pull-request' into...
[qemu.git] / migration / migration.h
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 "exec/cpu-common.h"
18 #include "hw/qdev-core.h"
19 #include "qapi/qapi-types-migration.h"
20 #include "qemu/thread.h"
21 #include "qemu/coroutine_int.h"
22 #include "io/channel.h"
23 #include "io/channel-buffer.h"
24 #include "net/announce.h"
25 #include "qom/object.h"
26
27 struct PostcopyBlocktimeContext;
28
29 #define MIGRATION_RESUME_ACK_VALUE (1)
30
31 /*
32 * 1<<6=64 pages -> 256K chunk when page size is 4K. This gives us
33 * the benefit that all the chunks are 64 pages aligned then the
34 * bitmaps are always aligned to LONG.
35 */
36 #define CLEAR_BITMAP_SHIFT_MIN 6
37 /*
38 * 1<<18=256K pages -> 1G chunk when page size is 4K. This is the
39 * default value to use if no one specified.
40 */
41 #define CLEAR_BITMAP_SHIFT_DEFAULT 18
42 /*
43 * 1<<31=2G pages -> 8T chunk when page size is 4K. This should be
44 * big enough and make sure we won't overflow easily.
45 */
46 #define CLEAR_BITMAP_SHIFT_MAX 31
47
48 /* State for the incoming migration */
49 struct MigrationIncomingState {
50 QEMUFile *from_src_file;
51
52 /*
53 * Free at the start of the main state load, set as the main thread finishes
54 * loading state.
55 */
56 QemuEvent main_thread_load_event;
57
58 /* For network announces */
59 AnnounceTimer announce_timer;
60
61 size_t largest_page_size;
62 bool have_fault_thread;
63 QemuThread fault_thread;
64 QemuSemaphore fault_thread_sem;
65 /* Set this when we want the fault thread to quit */
66 bool fault_thread_quit;
67
68 bool have_listen_thread;
69 QemuThread listen_thread;
70 QemuSemaphore listen_thread_sem;
71
72 /* For the kernel to send us notifications */
73 int userfault_fd;
74 /* To notify the fault_thread to wake, e.g., when need to quit */
75 int userfault_event_fd;
76 QEMUFile *to_src_file;
77 QemuMutex rp_mutex; /* We send replies from multiple threads */
78 /* RAMBlock of last request sent to source */
79 RAMBlock *last_rb;
80 void *postcopy_tmp_page;
81 void *postcopy_tmp_zero_page;
82 /* PostCopyFD's for external userfaultfds & handlers of shared memory */
83 GArray *postcopy_remote_fds;
84
85 QEMUBH *bh;
86
87 int state;
88
89 bool have_colo_incoming_thread;
90 QemuThread colo_incoming_thread;
91 /* The coroutine we should enter (back) after failover */
92 Coroutine *migration_incoming_co;
93 QemuSemaphore colo_incoming_sem;
94
95 /*
96 * PostcopyBlocktimeContext to keep information for postcopy
97 * live migration, to calculate vCPU block time
98 * */
99 struct PostcopyBlocktimeContext *blocktime_ctx;
100
101 /* notify PAUSED postcopy incoming migrations to try to continue */
102 bool postcopy_recover_triggered;
103 QemuSemaphore postcopy_pause_sem_dst;
104 QemuSemaphore postcopy_pause_sem_fault;
105
106 /* List of listening socket addresses */
107 SocketAddressList *socket_address_list;
108
109 /* A tree of pages that we requested to the source VM */
110 GTree *page_requested;
111 /* For debugging purpose only, but would be nice to keep */
112 int page_requested_count;
113 /*
114 * The mutex helps to maintain the requested pages that we sent to the
115 * source, IOW, to guarantee coherent between the page_requests tree and
116 * the per-ramblock receivedmap. Note! This does not guarantee consistency
117 * of the real page copy procedures (using UFFDIO_[ZERO]COPY). E.g., even
118 * if one bit in receivedmap is cleared, UFFDIO_COPY could have happened
119 * for that page already. This is intended so that the mutex won't
120 * serialize and blocked by slow operations like UFFDIO_* ioctls. However
121 * this should be enough to make sure the page_requested tree always
122 * contains valid information.
123 */
124 QemuMutex page_request_mutex;
125 };
126
127 MigrationIncomingState *migration_incoming_get_current(void);
128 void migration_incoming_state_destroy(void);
129 /*
130 * Functions to work with blocktime context
131 */
132 void fill_destination_postcopy_migration_info(MigrationInfo *info);
133
134 #define TYPE_MIGRATION "migration"
135
136 typedef struct MigrationClass MigrationClass;
137 DECLARE_OBJ_CHECKERS(MigrationState, MigrationClass,
138 MIGRATION_OBJ, TYPE_MIGRATION)
139
140 struct MigrationClass {
141 /*< private >*/
142 DeviceClass parent_class;
143 };
144
145 struct MigrationState {
146 /*< private >*/
147 DeviceState parent_obj;
148
149 /*< public >*/
150 QemuThread thread;
151 QEMUBH *vm_start_bh;
152 QEMUBH *cleanup_bh;
153 QEMUFile *to_dst_file;
154 QIOChannelBuffer *bioc;
155 /*
156 * Protects to_dst_file pointer. We need to make sure we won't
157 * yield or hang during the critical section, since this lock will
158 * be used in OOB command handler.
159 */
160 QemuMutex qemu_file_lock;
161
162 /*
163 * Used to allow urgent requests to override rate limiting.
164 */
165 QemuSemaphore rate_limit_sem;
166
167 /* pages already send at the beginning of current iteration */
168 uint64_t iteration_initial_pages;
169
170 /* pages transferred per second */
171 double pages_per_second;
172
173 /* bytes already send at the beginning of current iteration */
174 uint64_t iteration_initial_bytes;
175 /* time at the start of current iteration */
176 int64_t iteration_start_time;
177 /*
178 * The final stage happens when the remaining data is smaller than
179 * this threshold; it's calculated from the requested downtime and
180 * measured bandwidth
181 */
182 int64_t threshold_size;
183
184 /* params from 'migrate-set-parameters' */
185 MigrationParameters parameters;
186
187 int state;
188
189 /* State related to return path */
190 struct {
191 QEMUFile *from_dst_file;
192 QemuThread rp_thread;
193 bool error;
194 QemuSemaphore rp_sem;
195 } rp_state;
196
197 double mbps;
198 /* Timestamp when recent migration starts (ms) */
199 int64_t start_time;
200 /* Total time used by latest migration (ms) */
201 int64_t total_time;
202 /* Timestamp when VM is down (ms) to migrate the last stuff */
203 int64_t downtime_start;
204 int64_t downtime;
205 int64_t expected_downtime;
206 bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
207 int64_t setup_time;
208 /*
209 * Whether guest was running when we enter the completion stage.
210 * If migration is interrupted by any reason, we need to continue
211 * running the guest on source.
212 */
213 bool vm_was_running;
214
215 /* Flag set once the migration has been asked to enter postcopy */
216 bool start_postcopy;
217 /* Flag set after postcopy has sent the device state */
218 bool postcopy_after_devices;
219
220 /* Flag set once the migration thread is running (and needs joining) */
221 bool migration_thread_running;
222
223 /* Flag set once the migration thread called bdrv_inactivate_all */
224 bool block_inactive;
225
226 /* Migration is waiting for guest to unplug device */
227 QemuSemaphore wait_unplug_sem;
228
229 /* Migration is paused due to pause-before-switchover */
230 QemuSemaphore pause_sem;
231
232 /* The semaphore is used to notify COLO thread that failover is finished */
233 QemuSemaphore colo_exit_sem;
234
235 /* The event is used to notify COLO thread to do checkpoint */
236 QemuEvent colo_checkpoint_event;
237 int64_t colo_checkpoint_time;
238 QEMUTimer *colo_delay_timer;
239
240 /* The first error that has occurred.
241 We used the mutex to be able to return the 1st error message */
242 Error *error;
243 /* mutex to protect errp */
244 QemuMutex error_mutex;
245
246 /* Do we have to clean up -b/-i from old migrate parameters */
247 /* This feature is deprecated and will be removed */
248 bool must_remove_block_options;
249
250 /*
251 * Global switch on whether we need to store the global state
252 * during migration.
253 */
254 bool store_global_state;
255
256 /* Whether we send QEMU_VM_CONFIGURATION during migration */
257 bool send_configuration;
258 /* Whether we send section footer during migration */
259 bool send_section_footer;
260
261 /* Needed by postcopy-pause state */
262 QemuSemaphore postcopy_pause_sem;
263 QemuSemaphore postcopy_pause_rp_sem;
264 /*
265 * Whether we abort the migration if decompression errors are
266 * detected at the destination. It is left at false for qemu
267 * older than 3.0, since only newer qemu sends streams that
268 * do not trigger spurious decompression errors.
269 */
270 bool decompress_error_check;
271
272 /*
273 * This decides the size of guest memory chunk that will be used
274 * to track dirty bitmap clearing. The size of memory chunk will
275 * be GUEST_PAGE_SIZE << N. Say, N=0 means we will clear dirty
276 * bitmap for each page to send (1<<0=1); N=10 means we will clear
277 * dirty bitmap only once for 1<<10=1K continuous guest pages
278 * (which is in 4M chunk).
279 */
280 uint8_t clear_bitmap_shift;
281
282 /*
283 * This save hostname when out-going migration starts
284 */
285 char *hostname;
286 };
287
288 void migrate_set_state(int *state, int old_state, int new_state);
289
290 void migration_fd_process_incoming(QEMUFile *f, Error **errp);
291 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
292 void migration_incoming_process(void);
293
294 bool migration_has_all_channels(void);
295
296 uint64_t migrate_max_downtime(void);
297
298 void migrate_set_error(MigrationState *s, const Error *error);
299 void migrate_fd_error(MigrationState *s, const Error *error);
300
301 void migrate_fd_connect(MigrationState *s, Error *error_in);
302
303 bool migration_is_setup_or_active(int state);
304 bool migration_is_running(int state);
305
306 void migrate_init(MigrationState *s);
307 bool migration_is_blocked(Error **errp);
308 /* True if outgoing migration has entered postcopy phase */
309 bool migration_in_postcopy(void);
310 MigrationState *migrate_get_current(void);
311
312 bool migrate_postcopy(void);
313
314 bool migrate_release_ram(void);
315 bool migrate_postcopy_ram(void);
316 bool migrate_zero_blocks(void);
317 bool migrate_dirty_bitmaps(void);
318 bool migrate_ignore_shared(void);
319 bool migrate_validate_uuid(void);
320
321 bool migrate_auto_converge(void);
322 bool migrate_use_multifd(void);
323 bool migrate_pause_before_switchover(void);
324 int migrate_multifd_channels(void);
325 MultiFDCompression migrate_multifd_compression(void);
326 int migrate_multifd_zlib_level(void);
327 int migrate_multifd_zstd_level(void);
328
329 int migrate_use_xbzrle(void);
330 uint64_t migrate_xbzrle_cache_size(void);
331 bool migrate_colo_enabled(void);
332
333 bool migrate_use_block(void);
334 bool migrate_use_block_incremental(void);
335 int migrate_max_cpu_throttle(void);
336 bool migrate_use_return_path(void);
337
338 uint64_t ram_get_total_transferred_pages(void);
339
340 bool migrate_use_compression(void);
341 int migrate_compress_level(void);
342 int migrate_compress_threads(void);
343 int migrate_compress_wait_thread(void);
344 int migrate_decompress_threads(void);
345 bool migrate_use_events(void);
346 bool migrate_postcopy_blocktime(void);
347 bool migrate_background_snapshot(void);
348
349 /* Sending on the return path - generic and then for each message type */
350 void migrate_send_rp_shut(MigrationIncomingState *mis,
351 uint32_t value);
352 void migrate_send_rp_pong(MigrationIncomingState *mis,
353 uint32_t value);
354 int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb,
355 ram_addr_t start, uint64_t haddr);
356 int migrate_send_rp_message_req_pages(MigrationIncomingState *mis,
357 RAMBlock *rb, ram_addr_t start);
358 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
359 char *block_name);
360 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
361
362 void dirty_bitmap_mig_before_vm_start(void);
363 void dirty_bitmap_mig_cancel_outgoing(void);
364 void dirty_bitmap_mig_cancel_incoming(void);
365 bool check_dirty_bitmap_mig_alias_map(const BitmapMigrationNodeAliasList *bbm,
366 Error **errp);
367
368 void migrate_add_address(SocketAddress *address);
369
370 int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque);
371
372 #define qemu_ram_foreach_block \
373 #warning "Use foreach_not_ignored_block in migration code"
374
375 void migration_make_urgent_request(void);
376 void migration_consume_urgent_request(void);
377 bool migration_rate_limit(void);
378
379 #endif