xref: /openbmc/qemu/migration/migration.h (revision 58ea30f5)
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 "qemu-common.h"
18 #include "qapi/qapi-types-migration.h"
19 #include "qemu/thread.h"
20 #include "exec/cpu-common.h"
21 #include "qemu/coroutine_int.h"
22 #include "hw/qdev.h"
23 #include "io/channel.h"
24 #include "net/announce.h"
25 
26 struct PostcopyBlocktimeContext;
27 
28 #define  MIGRATION_RESUME_ACK_VALUE  (1)
29 
30 /* State for the incoming migration */
31 struct MigrationIncomingState {
32     QEMUFile *from_src_file;
33 
34     /*
35      * Free at the start of the main state load, set as the main thread finishes
36      * loading state.
37      */
38     QemuEvent main_thread_load_event;
39 
40     /* For network announces */
41     AnnounceTimer  announce_timer;
42 
43     size_t         largest_page_size;
44     bool           have_fault_thread;
45     QemuThread     fault_thread;
46     QemuSemaphore  fault_thread_sem;
47     /* Set this when we want the fault thread to quit */
48     bool           fault_thread_quit;
49 
50     bool           have_listen_thread;
51     QemuThread     listen_thread;
52     QemuSemaphore  listen_thread_sem;
53 
54     /* For the kernel to send us notifications */
55     int       userfault_fd;
56     /* To notify the fault_thread to wake, e.g., when need to quit */
57     int       userfault_event_fd;
58     QEMUFile *to_src_file;
59     QemuMutex rp_mutex;    /* We send replies from multiple threads */
60     /* RAMBlock of last request sent to source */
61     RAMBlock *last_rb;
62     void     *postcopy_tmp_page;
63     void     *postcopy_tmp_zero_page;
64     /* PostCopyFD's for external userfaultfds & handlers of shared memory */
65     GArray   *postcopy_remote_fds;
66 
67     QEMUBH *bh;
68 
69     int state;
70 
71     bool have_colo_incoming_thread;
72     QemuThread colo_incoming_thread;
73     /* The coroutine we should enter (back) after failover */
74     Coroutine *migration_incoming_co;
75     QemuSemaphore colo_incoming_sem;
76 
77     /*
78      * PostcopyBlocktimeContext to keep information for postcopy
79      * live migration, to calculate vCPU block time
80      * */
81     struct PostcopyBlocktimeContext *blocktime_ctx;
82 
83     /* notify PAUSED postcopy incoming migrations to try to continue */
84     bool postcopy_recover_triggered;
85     QemuSemaphore postcopy_pause_sem_dst;
86     QemuSemaphore postcopy_pause_sem_fault;
87 
88     /* List of listening socket addresses  */
89     SocketAddressList *socket_address_list;
90 };
91 
92 MigrationIncomingState *migration_incoming_get_current(void);
93 void migration_incoming_state_destroy(void);
94 /*
95  * Functions to work with blocktime context
96  */
97 void fill_destination_postcopy_migration_info(MigrationInfo *info);
98 
99 #define TYPE_MIGRATION "migration"
100 
101 #define MIGRATION_CLASS(klass) \
102     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
103 #define MIGRATION_OBJ(obj) \
104     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
105 #define MIGRATION_GET_CLASS(obj) \
106     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
107 
108 typedef struct MigrationClass {
109     /*< private >*/
110     DeviceClass parent_class;
111 } MigrationClass;
112 
113 struct MigrationState
114 {
115     /*< private >*/
116     DeviceState parent_obj;
117 
118     /*< public >*/
119     size_t bytes_xfer;
120     size_t xfer_limit;
121     QemuThread thread;
122     QEMUBH *cleanup_bh;
123     QEMUFile *to_dst_file;
124     /*
125      * Protects to_dst_file pointer.  We need to make sure we won't
126      * yield or hang during the critical section, since this lock will
127      * be used in OOB command handler.
128      */
129     QemuMutex qemu_file_lock;
130 
131     /*
132      * Used to allow urgent requests to override rate limiting.
133      */
134     QemuSemaphore rate_limit_sem;
135 
136     /* pages already send at the beginning of current iteration */
137     uint64_t iteration_initial_pages;
138 
139     /* pages transferred per second */
140     double pages_per_second;
141 
142     /* bytes already send at the beginning of current iteration */
143     uint64_t iteration_initial_bytes;
144     /* time at the start of current iteration */
145     int64_t iteration_start_time;
146     /*
147      * The final stage happens when the remaining data is smaller than
148      * this threshold; it's calculated from the requested downtime and
149      * measured bandwidth
150      */
151     int64_t threshold_size;
152 
153     /* params from 'migrate-set-parameters' */
154     MigrationParameters parameters;
155 
156     int state;
157 
158     /* State related to return path */
159     struct {
160         QEMUFile     *from_dst_file;
161         QemuThread    rp_thread;
162         bool          error;
163         QemuSemaphore rp_sem;
164     } rp_state;
165 
166     double mbps;
167     /* Timestamp when recent migration starts (ms) */
168     int64_t start_time;
169     /* Total time used by latest migration (ms) */
170     int64_t total_time;
171     /* Timestamp when VM is down (ms) to migrate the last stuff */
172     int64_t downtime_start;
173     int64_t downtime;
174     int64_t expected_downtime;
175     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
176     int64_t setup_time;
177     /*
178      * Whether guest was running when we enter the completion stage.
179      * If migration is interrupted by any reason, we need to continue
180      * running the guest on source.
181      */
182     bool vm_was_running;
183 
184     /* Flag set once the migration has been asked to enter postcopy */
185     bool start_postcopy;
186     /* Flag set after postcopy has sent the device state */
187     bool postcopy_after_devices;
188 
189     /* Flag set once the migration thread is running (and needs joining) */
190     bool migration_thread_running;
191 
192     /* Flag set once the migration thread called bdrv_inactivate_all */
193     bool block_inactive;
194 
195     /* Migration is paused due to pause-before-switchover */
196     QemuSemaphore pause_sem;
197 
198     /* The semaphore is used to notify COLO thread that failover is finished */
199     QemuSemaphore colo_exit_sem;
200 
201     /* The semaphore is used to notify COLO thread to do checkpoint */
202     QemuSemaphore colo_checkpoint_sem;
203     int64_t colo_checkpoint_time;
204     QEMUTimer *colo_delay_timer;
205 
206     /* The first error that has occurred.
207        We used the mutex to be able to return the 1st error message */
208     Error *error;
209     /* mutex to protect errp */
210     QemuMutex error_mutex;
211 
212     /* Do we have to clean up -b/-i from old migrate parameters */
213     /* This feature is deprecated and will be removed */
214     bool must_remove_block_options;
215 
216     /*
217      * Global switch on whether we need to store the global state
218      * during migration.
219      */
220     bool store_global_state;
221 
222     /* Whether we send QEMU_VM_CONFIGURATION during migration */
223     bool send_configuration;
224     /* Whether we send section footer during migration */
225     bool send_section_footer;
226 
227     /* Needed by postcopy-pause state */
228     QemuSemaphore postcopy_pause_sem;
229     QemuSemaphore postcopy_pause_rp_sem;
230     /*
231      * Whether we abort the migration if decompression errors are
232      * detected at the destination. It is left at false for qemu
233      * older than 3.0, since only newer qemu sends streams that
234      * do not trigger spurious decompression errors.
235      */
236     bool decompress_error_check;
237 };
238 
239 void migrate_set_state(int *state, int old_state, int new_state);
240 
241 void migration_fd_process_incoming(QEMUFile *f);
242 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
243 void migration_incoming_process(void);
244 
245 bool  migration_has_all_channels(void);
246 
247 uint64_t migrate_max_downtime(void);
248 
249 void migrate_set_error(MigrationState *s, const Error *error);
250 void migrate_fd_error(MigrationState *s, const Error *error);
251 
252 void migrate_fd_connect(MigrationState *s, Error *error_in);
253 
254 bool migration_is_setup_or_active(int state);
255 
256 void migrate_init(MigrationState *s);
257 bool migration_is_blocked(Error **errp);
258 /* True if outgoing migration has entered postcopy phase */
259 bool migration_in_postcopy(void);
260 MigrationState *migrate_get_current(void);
261 
262 bool migrate_postcopy(void);
263 
264 bool migrate_release_ram(void);
265 bool migrate_postcopy_ram(void);
266 bool migrate_zero_blocks(void);
267 bool migrate_dirty_bitmaps(void);
268 bool migrate_ignore_shared(void);
269 
270 bool migrate_auto_converge(void);
271 bool migrate_use_multifd(void);
272 bool migrate_pause_before_switchover(void);
273 int migrate_multifd_channels(void);
274 
275 int migrate_use_xbzrle(void);
276 int64_t migrate_xbzrle_cache_size(void);
277 bool migrate_colo_enabled(void);
278 
279 bool migrate_use_block(void);
280 bool migrate_use_block_incremental(void);
281 int migrate_max_cpu_throttle(void);
282 bool migrate_use_return_path(void);
283 
284 uint64_t ram_get_total_transferred_pages(void);
285 
286 bool migrate_use_compression(void);
287 int migrate_compress_level(void);
288 int migrate_compress_threads(void);
289 int migrate_compress_wait_thread(void);
290 int migrate_decompress_threads(void);
291 bool migrate_use_events(void);
292 bool migrate_postcopy_blocktime(void);
293 
294 /* Sending on the return path - generic and then for each message type */
295 void migrate_send_rp_shut(MigrationIncomingState *mis,
296                           uint32_t value);
297 void migrate_send_rp_pong(MigrationIncomingState *mis,
298                           uint32_t value);
299 int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
300                               ram_addr_t start, size_t len);
301 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
302                                  char *block_name);
303 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
304 
305 void dirty_bitmap_mig_before_vm_start(void);
306 void init_dirty_bitmap_incoming_migration(void);
307 void migrate_add_address(SocketAddress *address);
308 
309 int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque);
310 
311 #define qemu_ram_foreach_block \
312   #warning "Use foreach_not_ignored_block in migration code"
313 
314 void migration_make_urgent_request(void);
315 void migration_consume_urgent_request(void);
316 
317 #endif
318