]>
Commit | Line | Data |
---|---|---|
1b1d2e6d BP |
1 | |
2 | /* Copyright (c) 2009, 2010, 2011, 2016, 2017 Nicira, Inc. | |
3 | * | |
4 | * Licensed under the Apache License, Version 2.0 (the "License"); | |
5 | * you may not use this storage except in compliance with the License. | |
6 | * You may obtain a copy of the License at: | |
7 | * | |
8 | * http://www.apache.org/licenses/LICENSE-2.0 | |
9 | * | |
10 | * Unless required by applicable law or agreed to in writing, software | |
11 | * distributed under the License is distributed on an "AS IS" BASIS, | |
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
13 | * See the License for the specific language governing permissions and | |
14 | * limitations under the License. | |
15 | */ | |
16 | ||
17 | #include <config.h> | |
18 | ||
19 | #include "storage.h" | |
20 | #include <string.h> | |
21 | #include "log.h" | |
22 | #include "ovsdb-error.h" | |
23 | #include "openvswitch/json.h" | |
24 | #include "openvswitch/poll-loop.h" | |
25 | #include "openvswitch/vlog.h" | |
26 | #include "ovsdb.h" | |
27 | #include "raft.h" | |
28 | #include "random.h" | |
3423cd97 | 29 | #include "simap.h" |
1b1d2e6d BP |
30 | #include "timeval.h" |
31 | #include "util.h" | |
32 | ||
33 | VLOG_DEFINE_THIS_MODULE(storage); | |
34 | ||
35 | struct ovsdb_storage { | |
36 | /* There are three kinds of storage: | |
37 | * | |
38 | * - Standalone, backed by a disk file. 'log' is nonnull, 'raft' is | |
39 | * null. | |
40 | * | |
41 | * - Clustered, backed by a Raft cluster. 'log' is null, 'raft' is | |
42 | * nonnull. | |
43 | * | |
44 | * - Memory only, unbacked. 'log' and 'raft' are null. */ | |
45 | struct ovsdb_log *log; | |
46 | struct raft *raft; | |
47 | ||
48 | /* All kinds of storage. */ | |
49 | struct ovsdb_error *error; /* If nonnull, a permanent error. */ | |
50 | long long next_snapshot_min; /* Earliest time to take next snapshot. */ | |
51 | long long next_snapshot_max; /* Latest time to take next snapshot. */ | |
52 | ||
53 | /* Standalone only. */ | |
54 | unsigned int n_read; | |
55 | unsigned int n_written; | |
56 | }; | |
57 | ||
58 | static void schedule_next_snapshot(struct ovsdb_storage *, bool quick); | |
59 | ||
60 | static struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
61 | ovsdb_storage_open__(const char *filename, bool rw, bool allow_clustered, | |
62 | struct ovsdb_storage **storagep) | |
63 | { | |
64 | *storagep = NULL; | |
65 | ||
66 | struct ovsdb_log *log; | |
67 | struct ovsdb_error *error; | |
68 | error = ovsdb_log_open(filename, OVSDB_MAGIC"|"RAFT_MAGIC, | |
69 | rw ? OVSDB_LOG_READ_WRITE : OVSDB_LOG_READ_ONLY, | |
70 | -1, &log); | |
71 | if (error) { | |
72 | return error; | |
73 | } | |
74 | ||
75 | struct raft *raft = NULL; | |
76 | if (!strcmp(ovsdb_log_get_magic(log), RAFT_MAGIC)) { | |
77 | if (!allow_clustered) { | |
78 | ovsdb_log_close(log); | |
79 | return ovsdb_error(NULL, "%s: cannot apply this operation to " | |
80 | "clustered database file", filename); | |
81 | } | |
82 | error = raft_open(log, &raft); | |
83 | log = NULL; | |
84 | if (error) { | |
85 | return error; | |
86 | } | |
87 | } | |
88 | ||
89 | struct ovsdb_storage *storage = xzalloc(sizeof *storage); | |
90 | storage->log = log; | |
91 | storage->raft = raft; | |
92 | schedule_next_snapshot(storage, false); | |
93 | *storagep = storage; | |
94 | return NULL; | |
95 | } | |
96 | ||
97 | /* Opens 'filename' for use as storage. If 'rw', opens it for read/write | |
98 | * access, otherwise read-only. If successful, stores the new storage in | |
99 | * '*storagep' and returns NULL; on failure, stores NULL in '*storagep' and | |
100 | * returns the error. | |
101 | * | |
102 | * The returned storage might be clustered or standalone, depending on what the | |
103 | * disk file contains. */ | |
104 | struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
105 | ovsdb_storage_open(const char *filename, bool rw, | |
106 | struct ovsdb_storage **storagep) | |
107 | { | |
108 | return ovsdb_storage_open__(filename, rw, true, storagep); | |
109 | } | |
110 | ||
111 | struct ovsdb_storage * | |
112 | ovsdb_storage_open_standalone(const char *filename, bool rw) | |
113 | { | |
114 | struct ovsdb_storage *storage; | |
115 | struct ovsdb_error *error = ovsdb_storage_open__(filename, rw, false, | |
116 | &storage); | |
117 | if (error) { | |
118 | ovs_fatal(0, "%s", ovsdb_error_to_string_free(error)); | |
119 | } | |
120 | return storage; | |
121 | } | |
122 | ||
123 | /* Creates and returns new storage without any backing. Nothing will be read | |
124 | * from the storage, and writes are discarded. */ | |
125 | struct ovsdb_storage * | |
126 | ovsdb_storage_create_unbacked(void) | |
127 | { | |
128 | struct ovsdb_storage *storage = xzalloc(sizeof *storage); | |
129 | schedule_next_snapshot(storage, false); | |
130 | return storage; | |
131 | } | |
132 | ||
133 | void | |
134 | ovsdb_storage_close(struct ovsdb_storage *storage) | |
135 | { | |
136 | if (storage) { | |
137 | ovsdb_log_close(storage->log); | |
138 | raft_close(storage->raft); | |
139 | ovsdb_error_destroy(storage->error); | |
140 | free(storage); | |
141 | } | |
142 | } | |
143 | ||
144 | const char * | |
145 | ovsdb_storage_get_model(const struct ovsdb_storage *storage) | |
146 | { | |
147 | return storage->raft ? "clustered" : "standalone"; | |
148 | } | |
149 | ||
150 | bool | |
151 | ovsdb_storage_is_clustered(const struct ovsdb_storage *storage) | |
152 | { | |
153 | return storage->raft != NULL; | |
154 | } | |
155 | ||
156 | bool | |
157 | ovsdb_storage_is_connected(const struct ovsdb_storage *storage) | |
158 | { | |
159 | return !storage->raft || raft_is_connected(storage->raft); | |
160 | } | |
161 | ||
162 | bool | |
163 | ovsdb_storage_is_dead(const struct ovsdb_storage *storage) | |
164 | { | |
165 | return storage->raft && raft_left(storage->raft); | |
166 | } | |
167 | ||
168 | bool | |
169 | ovsdb_storage_is_leader(const struct ovsdb_storage *storage) | |
170 | { | |
171 | return !storage->raft || raft_is_leader(storage->raft); | |
172 | } | |
173 | ||
174 | const struct uuid * | |
175 | ovsdb_storage_get_cid(const struct ovsdb_storage *storage) | |
176 | { | |
177 | return storage->raft ? raft_get_cid(storage->raft) : NULL; | |
178 | } | |
179 | ||
180 | const struct uuid * | |
181 | ovsdb_storage_get_sid(const struct ovsdb_storage *storage) | |
182 | { | |
183 | return storage->raft ? raft_get_sid(storage->raft) : NULL; | |
184 | } | |
185 | ||
186 | uint64_t | |
187 | ovsdb_storage_get_applied_index(const struct ovsdb_storage *storage) | |
188 | { | |
189 | return storage->raft ? raft_get_applied_index(storage->raft) : 0; | |
190 | } | |
191 | ||
3423cd97 IM |
192 | void |
193 | ovsdb_storage_get_memory_usage(const struct ovsdb_storage *storage, | |
194 | struct simap *usage) | |
195 | { | |
196 | if (storage->raft) { | |
197 | raft_get_memory_usage(storage->raft, usage); | |
198 | } | |
199 | } | |
200 | ||
1b1d2e6d BP |
201 | void |
202 | ovsdb_storage_run(struct ovsdb_storage *storage) | |
203 | { | |
204 | if (storage->raft) { | |
205 | raft_run(storage->raft); | |
206 | } | |
207 | } | |
208 | ||
209 | void | |
210 | ovsdb_storage_wait(struct ovsdb_storage *storage) | |
211 | { | |
212 | if (storage->raft) { | |
213 | raft_wait(storage->raft); | |
214 | } | |
215 | } | |
216 | ||
217 | /* Returns 'storage''s embedded name, if it has one, otherwise null. | |
218 | * | |
219 | * Only clustered storage has a built-in name. */ | |
220 | const char * | |
221 | ovsdb_storage_get_name(const struct ovsdb_storage *storage) | |
222 | { | |
223 | return storage->raft ? raft_get_name(storage->raft) : NULL; | |
224 | } | |
225 | ||
226 | /* Attempts to read a log record from 'storage'. | |
227 | * | |
228 | * If successful, returns NULL and stores the transaction information in | |
229 | * '*schemap', '*txnp', and '*txnid'. At least one of these will be nonnull. | |
230 | * The caller owns the data and must eventually free it (with json_destroy()). | |
231 | * | |
232 | * If 'storage' is not clustered, 'txnid' may be null. | |
233 | * | |
234 | * If a read error occurs, returns the error and stores NULL in '*jsonp'. | |
235 | * | |
236 | * If the read reaches end of file, returns NULL and stores NULL in | |
237 | * '*jsonp'. */ | |
238 | struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
239 | ovsdb_storage_read(struct ovsdb_storage *storage, | |
240 | struct ovsdb_schema **schemap, | |
241 | struct json **txnp, | |
242 | struct uuid *txnid) | |
243 | { | |
244 | *schemap = NULL; | |
245 | *txnp = NULL; | |
246 | if (txnid) { | |
247 | *txnid = UUID_ZERO; | |
248 | } | |
249 | ||
250 | struct json *json; | |
251 | struct json *schema_json = NULL; | |
252 | struct json *txn_json = NULL; | |
253 | if (storage->raft) { | |
254 | bool is_snapshot; | |
255 | json = json_nullable_clone( | |
256 | raft_next_entry(storage->raft, txnid, &is_snapshot)); | |
257 | if (!json) { | |
258 | return NULL; | |
fa37affa | 259 | } else if (json->type != JSON_ARRAY || json->array.n != 2) { |
1b1d2e6d BP |
260 | json_destroy(json); |
261 | return ovsdb_error(NULL, "invalid commit format"); | |
262 | } | |
263 | ||
fa37affa | 264 | struct json **e = json->array.elems; |
1b1d2e6d BP |
265 | schema_json = e[0]->type != JSON_NULL ? e[0] : NULL; |
266 | txn_json = e[1]->type != JSON_NULL ? e[1] : NULL; | |
267 | } else if (storage->log) { | |
268 | struct ovsdb_error *error = ovsdb_log_read(storage->log, &json); | |
269 | if (error || !json) { | |
270 | return error; | |
271 | } | |
272 | ||
273 | unsigned int n = storage->n_read++; | |
274 | struct json **jsonp = !n ? &schema_json : &txn_json; | |
275 | *jsonp = json; | |
276 | if (n == 1) { | |
277 | ovsdb_log_mark_base(storage->log); | |
278 | } | |
279 | } else { | |
280 | /* Unbacked. Nothing to do. */ | |
281 | return NULL; | |
282 | } | |
283 | ||
284 | /* If we got this far then we must have at least a schema or a | |
285 | * transaction. */ | |
286 | ovs_assert(schema_json || txn_json); | |
287 | ||
288 | if (schema_json) { | |
289 | struct ovsdb_schema *schema; | |
290 | struct ovsdb_error *error = ovsdb_schema_from_json(schema_json, | |
291 | &schema); | |
292 | if (error) { | |
293 | json_destroy(json); | |
294 | return error; | |
295 | } | |
296 | ||
297 | const char *storage_name = ovsdb_storage_get_name(storage); | |
298 | const char *schema_name = schema->name; | |
299 | if (storage_name && strcmp(storage_name, schema_name)) { | |
300 | error = ovsdb_error(NULL, "name %s in header does not match " | |
301 | "name %s in schema", | |
302 | storage_name, schema_name); | |
303 | json_destroy(json); | |
304 | ovsdb_schema_destroy(schema); | |
305 | return error; | |
306 | } | |
307 | ||
308 | *schemap = schema; | |
309 | } | |
310 | ||
311 | if (txn_json) { | |
312 | *txnp = json_clone(txn_json); | |
313 | } | |
314 | ||
315 | json_destroy(json); | |
316 | return NULL; | |
317 | } | |
318 | ||
319 | /* Reads and returns the schema from standalone storage 'storage'. Terminates | |
320 | * with an error on failure. */ | |
321 | struct ovsdb_schema * | |
322 | ovsdb_storage_read_schema(struct ovsdb_storage *storage) | |
323 | { | |
324 | ovs_assert(storage->log); | |
325 | ||
326 | struct json *txn_json; | |
327 | struct ovsdb_schema *schema; | |
328 | struct ovsdb_error *error = ovsdb_storage_read(storage, &schema, | |
329 | &txn_json, NULL); | |
330 | if (error) { | |
331 | ovs_fatal(0, "%s", ovsdb_error_to_string_free(error)); | |
332 | } | |
333 | if (!schema && !txn_json) { | |
334 | ovs_fatal(0, "unexpected end of file reading schema"); | |
335 | } | |
336 | ovs_assert(schema && !txn_json); | |
337 | ||
338 | return schema; | |
339 | } | |
340 | ||
341 | bool | |
342 | ovsdb_storage_read_wait(struct ovsdb_storage *storage) | |
343 | { | |
344 | return (storage->raft | |
345 | ? raft_has_next_entry(storage->raft) | |
346 | : false); | |
347 | } | |
348 | ||
349 | void | |
350 | ovsdb_storage_unread(struct ovsdb_storage *storage) | |
351 | { | |
352 | if (storage->error) { | |
353 | return; | |
354 | } | |
355 | ||
356 | if (storage->raft) { | |
357 | if (!storage->error) { | |
358 | storage->error = ovsdb_error(NULL, "inconsistent data"); | |
359 | } | |
360 | } else if (storage->log) { | |
361 | ovsdb_log_unread(storage->log); | |
362 | } | |
363 | } | |
364 | ||
365 | struct ovsdb_write { | |
366 | struct ovsdb_error *error; | |
367 | struct raft_command *command; | |
368 | }; | |
369 | ||
370 | /* Not suitable for writing transactions that change the schema. */ | |
371 | struct ovsdb_write * OVS_WARN_UNUSED_RESULT | |
372 | ovsdb_storage_write(struct ovsdb_storage *storage, const struct json *data, | |
373 | const struct uuid *prereq, struct uuid *resultp, | |
374 | bool durable) | |
375 | { | |
376 | struct ovsdb_write *w = xzalloc(sizeof *w); | |
377 | struct uuid result = UUID_ZERO; | |
378 | if (storage->error) { | |
379 | w->error = ovsdb_error_clone(storage->error); | |
380 | } else if (storage->raft) { | |
381 | struct json *txn_json = json_array_create_2(json_null_create(), | |
382 | json_clone(data)); | |
383 | w->command = raft_command_execute(storage->raft, txn_json, | |
384 | prereq, &result); | |
385 | json_destroy(txn_json); | |
386 | } else if (storage->log) { | |
387 | w->error = ovsdb_log_write(storage->log, data); | |
388 | if (!w->error) { | |
389 | storage->n_written++; | |
390 | if (durable) { | |
391 | w->error = ovsdb_log_commit_block(storage->log); | |
392 | } | |
393 | } | |
394 | } else { | |
395 | /* When 'error' and 'command' are both null, it indicates that the | |
396 | * command is complete. This is fine since this unbacked storage drops | |
397 | * writes. */ | |
398 | } | |
399 | if (resultp) { | |
400 | *resultp = result; | |
401 | } | |
402 | return w; | |
403 | } | |
404 | ||
405 | /* Not suitable for writing transactions that change the schema. */ | |
406 | struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
407 | ovsdb_storage_write_block(struct ovsdb_storage *storage, | |
408 | const struct json *data, const struct uuid *prereq, | |
409 | struct uuid *resultp, bool durable) | |
410 | { | |
411 | struct ovsdb_write *w = ovsdb_storage_write(storage, data, | |
412 | prereq, resultp, durable); | |
413 | while (!ovsdb_write_is_complete(w)) { | |
414 | if (storage->raft) { | |
415 | raft_run(storage->raft); | |
416 | } | |
417 | ||
418 | ovsdb_write_wait(w); | |
419 | if (storage->raft) { | |
420 | raft_wait(storage->raft); | |
421 | } | |
422 | poll_block(); | |
423 | } | |
424 | ||
425 | struct ovsdb_error *error = ovsdb_error_clone(ovsdb_write_get_error(w)); | |
426 | ovsdb_write_destroy(w); | |
427 | return error; | |
428 | } | |
429 | ||
430 | bool | |
431 | ovsdb_write_is_complete(const struct ovsdb_write *w) | |
432 | { | |
433 | return (w->error | |
434 | || !w->command | |
435 | || raft_command_get_status(w->command) != RAFT_CMD_INCOMPLETE); | |
436 | } | |
437 | ||
438 | const struct ovsdb_error * | |
439 | ovsdb_write_get_error(const struct ovsdb_write *w_) | |
440 | { | |
441 | struct ovsdb_write *w = CONST_CAST(struct ovsdb_write *, w_); | |
442 | ovs_assert(ovsdb_write_is_complete(w)); | |
443 | ||
444 | if (w->command && !w->error) { | |
445 | enum raft_command_status status = raft_command_get_status(w->command); | |
446 | if (status != RAFT_CMD_SUCCESS) { | |
447 | w->error = ovsdb_error("cluster error", "%s", | |
448 | raft_command_status_to_string(status)); | |
449 | } | |
450 | } | |
451 | ||
452 | return w->error; | |
453 | } | |
454 | ||
455 | uint64_t | |
456 | ovsdb_write_get_commit_index(const struct ovsdb_write *w) | |
457 | { | |
458 | ovs_assert(ovsdb_write_is_complete(w)); | |
459 | return (w->command && !w->error | |
460 | ? raft_command_get_commit_index(w->command) | |
461 | : 0); | |
462 | } | |
463 | ||
464 | void | |
465 | ovsdb_write_wait(const struct ovsdb_write *w) | |
466 | { | |
467 | if (ovsdb_write_is_complete(w)) { | |
468 | poll_immediate_wake(); | |
469 | } | |
470 | } | |
471 | ||
472 | void | |
473 | ovsdb_write_destroy(struct ovsdb_write *w) | |
474 | { | |
475 | if (w) { | |
476 | raft_command_unref(w->command); | |
477 | ovsdb_error_destroy(w->error); | |
478 | free(w); | |
479 | } | |
480 | } | |
481 | ||
482 | static void | |
483 | schedule_next_snapshot(struct ovsdb_storage *storage, bool quick) | |
484 | { | |
485 | if (storage->log || storage->raft) { | |
486 | unsigned int base = 10 * 60 * 1000; /* 10 minutes */ | |
487 | unsigned int range = 10 * 60 * 1000; /* 10 minutes */ | |
488 | if (quick) { | |
489 | base /= 10; | |
490 | range /= 10; | |
491 | } | |
492 | ||
493 | long long int now = time_msec(); | |
494 | storage->next_snapshot_min = now + base + random_range(range); | |
495 | storage->next_snapshot_max = now + 60LL * 60 * 24 * 1000; /* 1 day */ | |
496 | } else { | |
497 | storage->next_snapshot_min = LLONG_MAX; | |
498 | storage->next_snapshot_max = LLONG_MAX; | |
499 | } | |
500 | } | |
501 | ||
502 | bool | |
503 | ovsdb_storage_should_snapshot(const struct ovsdb_storage *storage) | |
504 | { | |
505 | if (storage->raft || storage->log) { | |
506 | /* If we haven't reached the minimum snapshot time, don't snapshot. */ | |
507 | long long int now = time_msec(); | |
508 | if (now < storage->next_snapshot_min) { | |
509 | return false; | |
510 | } | |
511 | ||
512 | /* If we can't snapshot right now, don't. */ | |
513 | if (storage->raft && !raft_may_snapshot(storage->raft)) { | |
514 | return false; | |
515 | } | |
516 | ||
517 | uint64_t log_len = (storage->raft | |
518 | ? raft_get_log_length(storage->raft) | |
519 | : storage->n_read + storage->n_written); | |
520 | if (now < storage->next_snapshot_max) { | |
521 | /* Maximum snapshot time not yet reached. Take a snapshot if there | |
522 | * have been at least 100 log entries and the log file size has | |
523 | * grown a lot. */ | |
524 | bool grew_lots = (storage->raft | |
525 | ? raft_grew_lots(storage->raft) | |
526 | : ovsdb_log_grew_lots(storage->log)); | |
527 | return log_len >= 100 && grew_lots; | |
528 | } else { | |
529 | /* We have reached the maximum snapshot time. Take a snapshot if | |
530 | * there have been any log entries at all. */ | |
531 | return log_len > 0; | |
532 | } | |
533 | } | |
534 | ||
535 | return false; | |
536 | } | |
537 | ||
538 | static struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
539 | ovsdb_storage_store_snapshot__(struct ovsdb_storage *storage, | |
540 | const struct json *schema, | |
541 | const struct json *data) | |
542 | { | |
543 | if (storage->raft) { | |
544 | struct json *entries = json_array_create_empty(); | |
545 | if (schema) { | |
546 | json_array_add(entries, json_clone(schema)); | |
547 | } | |
548 | if (data) { | |
549 | json_array_add(entries, json_clone(data)); | |
550 | } | |
551 | struct ovsdb_error *error = raft_store_snapshot(storage->raft, | |
552 | entries); | |
553 | json_destroy(entries); | |
554 | return error; | |
555 | } else if (storage->log) { | |
556 | struct json *entries[2]; | |
557 | size_t n = 0; | |
558 | if (schema) { | |
559 | entries[n++] = CONST_CAST(struct json *, schema); | |
560 | } | |
561 | if (data) { | |
562 | entries[n++] = CONST_CAST(struct json *, data); | |
563 | } | |
564 | return ovsdb_log_replace(storage->log, entries, n); | |
565 | } else { | |
566 | return NULL; | |
567 | } | |
568 | } | |
569 | ||
570 | /* 'schema' and 'data' should faithfully represent the current schema and data, | |
571 | * otherwise the two storing backing formats will yield divergent results. Use | |
572 | * ovsdb_storage_write_schema_change() to change the schema. */ | |
573 | struct ovsdb_error * OVS_WARN_UNUSED_RESULT | |
574 | ovsdb_storage_store_snapshot(struct ovsdb_storage *storage, | |
575 | const struct json *schema, | |
576 | const struct json *data) | |
577 | { | |
578 | struct ovsdb_error *error = ovsdb_storage_store_snapshot__(storage, | |
579 | schema, data); | |
580 | bool retry_quickly = error != NULL; | |
581 | schedule_next_snapshot(storage, retry_quickly); | |
582 | return error; | |
583 | } | |
584 | ||
585 | struct ovsdb_write * OVS_WARN_UNUSED_RESULT | |
586 | ovsdb_storage_write_schema_change(struct ovsdb_storage *storage, | |
587 | const struct json *schema, | |
588 | const struct json *data, | |
589 | const struct uuid *prereq, | |
590 | struct uuid *resultp) | |
591 | { | |
592 | struct ovsdb_write *w = xzalloc(sizeof *w); | |
593 | struct uuid result = UUID_ZERO; | |
594 | if (storage->error) { | |
595 | w->error = ovsdb_error_clone(storage->error); | |
596 | } else if (storage->raft) { | |
597 | struct json *txn_json = json_array_create_2(json_clone(schema), | |
598 | json_clone(data)); | |
599 | w->command = raft_command_execute(storage->raft, txn_json, | |
600 | prereq, &result); | |
601 | json_destroy(txn_json); | |
602 | } else if (storage->log) { | |
603 | w->error = ovsdb_storage_store_snapshot__(storage, schema, data); | |
604 | } else { | |
605 | /* When 'error' and 'command' are both null, it indicates that the | |
606 | * command is complete. This is fine since this unbacked storage drops | |
607 | * writes. */ | |
608 | } | |
609 | if (resultp) { | |
610 | *resultp = result; | |
611 | } | |
612 | return w; | |
613 | } | |
2cd62f75 HZ |
614 | |
615 | const struct uuid * | |
616 | ovsdb_storage_peek_last_eid(struct ovsdb_storage *storage) | |
617 | { | |
618 | if (!storage->raft) { | |
619 | return NULL; | |
620 | } | |
621 | return raft_current_eid(storage->raft); | |
622 | } |