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56e93d26 JQ |
1 | /* |
2 | * QEMU System Emulator | |
3 | * | |
4 | * Copyright (c) 2003-2008 Fabrice Bellard | |
76cc7b58 JQ |
5 | * Copyright (c) 2011-2015 Red Hat Inc |
6 | * | |
7 | * Authors: | |
8 | * Juan Quintela <quintela@redhat.com> | |
56e93d26 JQ |
9 | * |
10 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
11 | * of this software and associated documentation files (the "Software"), to deal | |
12 | * in the Software without restriction, including without limitation the rights | |
13 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
14 | * copies of the Software, and to permit persons to whom the Software is | |
15 | * furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice shall be included in | |
18 | * all copies or substantial portions of the Software. | |
19 | * | |
20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
23 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
24 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
25 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
26 | * THE SOFTWARE. | |
27 | */ | |
1393a485 | 28 | #include "qemu/osdep.h" |
33c11879 PB |
29 | #include "qemu-common.h" |
30 | #include "cpu.h" | |
56e93d26 | 31 | #include <zlib.h> |
4addcd4f | 32 | #include "qapi-event.h" |
f348b6d1 | 33 | #include "qemu/cutils.h" |
56e93d26 JQ |
34 | #include "qemu/bitops.h" |
35 | #include "qemu/bitmap.h" | |
7205c9ec JQ |
36 | #include "qemu/timer.h" |
37 | #include "qemu/main-loop.h" | |
56e93d26 | 38 | #include "migration/migration.h" |
e0b266f0 | 39 | #include "migration/postcopy-ram.h" |
56e93d26 JQ |
40 | #include "exec/address-spaces.h" |
41 | #include "migration/page_cache.h" | |
56e93d26 | 42 | #include "qemu/error-report.h" |
56e93d26 | 43 | #include "trace.h" |
56e93d26 | 44 | #include "exec/ram_addr.h" |
56e93d26 | 45 | #include "qemu/rcu_queue.h" |
a91246c9 | 46 | #include "migration/colo.h" |
56e93d26 | 47 | |
56e93d26 | 48 | static int dirty_rate_high_cnt; |
56e93d26 JQ |
49 | |
50 | static uint64_t bitmap_sync_count; | |
51 | ||
52 | /***********************************************************/ | |
53 | /* ram save/restore */ | |
54 | ||
55 | #define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */ | |
56 | #define RAM_SAVE_FLAG_COMPRESS 0x02 | |
57 | #define RAM_SAVE_FLAG_MEM_SIZE 0x04 | |
58 | #define RAM_SAVE_FLAG_PAGE 0x08 | |
59 | #define RAM_SAVE_FLAG_EOS 0x10 | |
60 | #define RAM_SAVE_FLAG_CONTINUE 0x20 | |
61 | #define RAM_SAVE_FLAG_XBZRLE 0x40 | |
62 | /* 0x80 is reserved in migration.h start with 0x100 next */ | |
63 | #define RAM_SAVE_FLAG_COMPRESS_PAGE 0x100 | |
64 | ||
adb65dec | 65 | static uint8_t *ZERO_TARGET_PAGE; |
56e93d26 JQ |
66 | |
67 | static inline bool is_zero_range(uint8_t *p, uint64_t size) | |
68 | { | |
a1febc49 | 69 | return buffer_is_zero(p, size); |
56e93d26 JQ |
70 | } |
71 | ||
72 | /* struct contains XBZRLE cache and a static page | |
73 | used by the compression */ | |
74 | static struct { | |
75 | /* buffer used for XBZRLE encoding */ | |
76 | uint8_t *encoded_buf; | |
77 | /* buffer for storing page content */ | |
78 | uint8_t *current_buf; | |
79 | /* Cache for XBZRLE, Protected by lock. */ | |
80 | PageCache *cache; | |
81 | QemuMutex lock; | |
82 | } XBZRLE; | |
83 | ||
84 | /* buffer used for XBZRLE decoding */ | |
85 | static uint8_t *xbzrle_decoded_buf; | |
86 | ||
87 | static void XBZRLE_cache_lock(void) | |
88 | { | |
89 | if (migrate_use_xbzrle()) | |
90 | qemu_mutex_lock(&XBZRLE.lock); | |
91 | } | |
92 | ||
93 | static void XBZRLE_cache_unlock(void) | |
94 | { | |
95 | if (migrate_use_xbzrle()) | |
96 | qemu_mutex_unlock(&XBZRLE.lock); | |
97 | } | |
98 | ||
3d0684b2 JQ |
99 | /** |
100 | * xbzrle_cache_resize: resize the xbzrle cache | |
101 | * | |
102 | * This function is called from qmp_migrate_set_cache_size in main | |
103 | * thread, possibly while a migration is in progress. A running | |
104 | * migration may be using the cache and might finish during this call, | |
105 | * hence changes to the cache are protected by XBZRLE.lock(). | |
106 | * | |
107 | * Returns the new_size or negative in case of error. | |
108 | * | |
109 | * @new_size: new cache size | |
56e93d26 JQ |
110 | */ |
111 | int64_t xbzrle_cache_resize(int64_t new_size) | |
112 | { | |
113 | PageCache *new_cache; | |
114 | int64_t ret; | |
115 | ||
116 | if (new_size < TARGET_PAGE_SIZE) { | |
117 | return -1; | |
118 | } | |
119 | ||
120 | XBZRLE_cache_lock(); | |
121 | ||
122 | if (XBZRLE.cache != NULL) { | |
123 | if (pow2floor(new_size) == migrate_xbzrle_cache_size()) { | |
124 | goto out_new_size; | |
125 | } | |
126 | new_cache = cache_init(new_size / TARGET_PAGE_SIZE, | |
127 | TARGET_PAGE_SIZE); | |
128 | if (!new_cache) { | |
129 | error_report("Error creating cache"); | |
130 | ret = -1; | |
131 | goto out; | |
132 | } | |
133 | ||
134 | cache_fini(XBZRLE.cache); | |
135 | XBZRLE.cache = new_cache; | |
136 | } | |
137 | ||
138 | out_new_size: | |
139 | ret = pow2floor(new_size); | |
140 | out: | |
141 | XBZRLE_cache_unlock(); | |
142 | return ret; | |
143 | } | |
144 | ||
6f37bb8b JQ |
145 | /* State of RAM for migration */ |
146 | struct RAMState { | |
147 | /* Last block that we have visited searching for dirty pages */ | |
148 | RAMBlock *last_seen_block; | |
149 | /* Last block from where we have sent data */ | |
150 | RAMBlock *last_sent_block; | |
151 | /* Last offset we have sent data from */ | |
152 | ram_addr_t last_offset; | |
153 | /* last ram version we have seen */ | |
154 | uint32_t last_version; | |
155 | /* We are in the first round */ | |
156 | bool ram_bulk_stage; | |
157 | }; | |
158 | typedef struct RAMState RAMState; | |
159 | ||
160 | static RAMState ram_state; | |
161 | ||
56e93d26 JQ |
162 | /* accounting for migration statistics */ |
163 | typedef struct AccountingInfo { | |
164 | uint64_t dup_pages; | |
165 | uint64_t skipped_pages; | |
166 | uint64_t norm_pages; | |
167 | uint64_t iterations; | |
168 | uint64_t xbzrle_bytes; | |
169 | uint64_t xbzrle_pages; | |
170 | uint64_t xbzrle_cache_miss; | |
171 | double xbzrle_cache_miss_rate; | |
172 | uint64_t xbzrle_overflows; | |
173 | } AccountingInfo; | |
174 | ||
175 | static AccountingInfo acct_info; | |
176 | ||
177 | static void acct_clear(void) | |
178 | { | |
179 | memset(&acct_info, 0, sizeof(acct_info)); | |
180 | } | |
181 | ||
182 | uint64_t dup_mig_bytes_transferred(void) | |
183 | { | |
184 | return acct_info.dup_pages * TARGET_PAGE_SIZE; | |
185 | } | |
186 | ||
187 | uint64_t dup_mig_pages_transferred(void) | |
188 | { | |
189 | return acct_info.dup_pages; | |
190 | } | |
191 | ||
192 | uint64_t skipped_mig_bytes_transferred(void) | |
193 | { | |
194 | return acct_info.skipped_pages * TARGET_PAGE_SIZE; | |
195 | } | |
196 | ||
197 | uint64_t skipped_mig_pages_transferred(void) | |
198 | { | |
199 | return acct_info.skipped_pages; | |
200 | } | |
201 | ||
202 | uint64_t norm_mig_bytes_transferred(void) | |
203 | { | |
204 | return acct_info.norm_pages * TARGET_PAGE_SIZE; | |
205 | } | |
206 | ||
207 | uint64_t norm_mig_pages_transferred(void) | |
208 | { | |
209 | return acct_info.norm_pages; | |
210 | } | |
211 | ||
212 | uint64_t xbzrle_mig_bytes_transferred(void) | |
213 | { | |
214 | return acct_info.xbzrle_bytes; | |
215 | } | |
216 | ||
217 | uint64_t xbzrle_mig_pages_transferred(void) | |
218 | { | |
219 | return acct_info.xbzrle_pages; | |
220 | } | |
221 | ||
222 | uint64_t xbzrle_mig_pages_cache_miss(void) | |
223 | { | |
224 | return acct_info.xbzrle_cache_miss; | |
225 | } | |
226 | ||
227 | double xbzrle_mig_cache_miss_rate(void) | |
228 | { | |
229 | return acct_info.xbzrle_cache_miss_rate; | |
230 | } | |
231 | ||
232 | uint64_t xbzrle_mig_pages_overflow(void) | |
233 | { | |
234 | return acct_info.xbzrle_overflows; | |
235 | } | |
236 | ||
dd631697 | 237 | static QemuMutex migration_bitmap_mutex; |
56e93d26 | 238 | static uint64_t migration_dirty_pages; |
56e93d26 | 239 | |
b8fb8cb7 DDAG |
240 | /* used by the search for pages to send */ |
241 | struct PageSearchStatus { | |
242 | /* Current block being searched */ | |
243 | RAMBlock *block; | |
244 | /* Current offset to search from */ | |
245 | ram_addr_t offset; | |
246 | /* Set once we wrap around */ | |
247 | bool complete_round; | |
248 | }; | |
249 | typedef struct PageSearchStatus PageSearchStatus; | |
250 | ||
60be6340 DL |
251 | static struct BitmapRcu { |
252 | struct rcu_head rcu; | |
f3f491fc | 253 | /* Main migration bitmap */ |
60be6340 | 254 | unsigned long *bmap; |
f3f491fc DDAG |
255 | /* bitmap of pages that haven't been sent even once |
256 | * only maintained and used in postcopy at the moment | |
257 | * where it's used to send the dirtymap at the start | |
258 | * of the postcopy phase | |
259 | */ | |
260 | unsigned long *unsentmap; | |
60be6340 DL |
261 | } *migration_bitmap_rcu; |
262 | ||
56e93d26 | 263 | struct CompressParam { |
56e93d26 | 264 | bool done; |
90e56fb4 | 265 | bool quit; |
56e93d26 JQ |
266 | QEMUFile *file; |
267 | QemuMutex mutex; | |
268 | QemuCond cond; | |
269 | RAMBlock *block; | |
270 | ram_addr_t offset; | |
271 | }; | |
272 | typedef struct CompressParam CompressParam; | |
273 | ||
274 | struct DecompressParam { | |
73a8912b | 275 | bool done; |
90e56fb4 | 276 | bool quit; |
56e93d26 JQ |
277 | QemuMutex mutex; |
278 | QemuCond cond; | |
279 | void *des; | |
d341d9f3 | 280 | uint8_t *compbuf; |
56e93d26 JQ |
281 | int len; |
282 | }; | |
283 | typedef struct DecompressParam DecompressParam; | |
284 | ||
285 | static CompressParam *comp_param; | |
286 | static QemuThread *compress_threads; | |
287 | /* comp_done_cond is used to wake up the migration thread when | |
288 | * one of the compression threads has finished the compression. | |
289 | * comp_done_lock is used to co-work with comp_done_cond. | |
290 | */ | |
0d9f9a5c LL |
291 | static QemuMutex comp_done_lock; |
292 | static QemuCond comp_done_cond; | |
56e93d26 JQ |
293 | /* The empty QEMUFileOps will be used by file in CompressParam */ |
294 | static const QEMUFileOps empty_ops = { }; | |
295 | ||
296 | static bool compression_switch; | |
56e93d26 JQ |
297 | static DecompressParam *decomp_param; |
298 | static QemuThread *decompress_threads; | |
73a8912b LL |
299 | static QemuMutex decomp_done_lock; |
300 | static QemuCond decomp_done_cond; | |
56e93d26 | 301 | |
a7a9a88f LL |
302 | static int do_compress_ram_page(QEMUFile *f, RAMBlock *block, |
303 | ram_addr_t offset); | |
56e93d26 JQ |
304 | |
305 | static void *do_data_compress(void *opaque) | |
306 | { | |
307 | CompressParam *param = opaque; | |
a7a9a88f LL |
308 | RAMBlock *block; |
309 | ram_addr_t offset; | |
56e93d26 | 310 | |
a7a9a88f | 311 | qemu_mutex_lock(¶m->mutex); |
90e56fb4 | 312 | while (!param->quit) { |
a7a9a88f LL |
313 | if (param->block) { |
314 | block = param->block; | |
315 | offset = param->offset; | |
316 | param->block = NULL; | |
317 | qemu_mutex_unlock(¶m->mutex); | |
318 | ||
319 | do_compress_ram_page(param->file, block, offset); | |
320 | ||
0d9f9a5c | 321 | qemu_mutex_lock(&comp_done_lock); |
a7a9a88f | 322 | param->done = true; |
0d9f9a5c LL |
323 | qemu_cond_signal(&comp_done_cond); |
324 | qemu_mutex_unlock(&comp_done_lock); | |
a7a9a88f LL |
325 | |
326 | qemu_mutex_lock(¶m->mutex); | |
327 | } else { | |
56e93d26 JQ |
328 | qemu_cond_wait(¶m->cond, ¶m->mutex); |
329 | } | |
56e93d26 | 330 | } |
a7a9a88f | 331 | qemu_mutex_unlock(¶m->mutex); |
56e93d26 JQ |
332 | |
333 | return NULL; | |
334 | } | |
335 | ||
336 | static inline void terminate_compression_threads(void) | |
337 | { | |
338 | int idx, thread_count; | |
339 | ||
340 | thread_count = migrate_compress_threads(); | |
3d0684b2 | 341 | |
56e93d26 JQ |
342 | for (idx = 0; idx < thread_count; idx++) { |
343 | qemu_mutex_lock(&comp_param[idx].mutex); | |
90e56fb4 | 344 | comp_param[idx].quit = true; |
56e93d26 JQ |
345 | qemu_cond_signal(&comp_param[idx].cond); |
346 | qemu_mutex_unlock(&comp_param[idx].mutex); | |
347 | } | |
348 | } | |
349 | ||
350 | void migrate_compress_threads_join(void) | |
351 | { | |
352 | int i, thread_count; | |
353 | ||
354 | if (!migrate_use_compression()) { | |
355 | return; | |
356 | } | |
357 | terminate_compression_threads(); | |
358 | thread_count = migrate_compress_threads(); | |
359 | for (i = 0; i < thread_count; i++) { | |
360 | qemu_thread_join(compress_threads + i); | |
361 | qemu_fclose(comp_param[i].file); | |
362 | qemu_mutex_destroy(&comp_param[i].mutex); | |
363 | qemu_cond_destroy(&comp_param[i].cond); | |
364 | } | |
0d9f9a5c LL |
365 | qemu_mutex_destroy(&comp_done_lock); |
366 | qemu_cond_destroy(&comp_done_cond); | |
56e93d26 JQ |
367 | g_free(compress_threads); |
368 | g_free(comp_param); | |
56e93d26 JQ |
369 | compress_threads = NULL; |
370 | comp_param = NULL; | |
56e93d26 JQ |
371 | } |
372 | ||
373 | void migrate_compress_threads_create(void) | |
374 | { | |
375 | int i, thread_count; | |
376 | ||
377 | if (!migrate_use_compression()) { | |
378 | return; | |
379 | } | |
56e93d26 JQ |
380 | compression_switch = true; |
381 | thread_count = migrate_compress_threads(); | |
382 | compress_threads = g_new0(QemuThread, thread_count); | |
383 | comp_param = g_new0(CompressParam, thread_count); | |
0d9f9a5c LL |
384 | qemu_cond_init(&comp_done_cond); |
385 | qemu_mutex_init(&comp_done_lock); | |
56e93d26 | 386 | for (i = 0; i < thread_count; i++) { |
e110aa91 C |
387 | /* comp_param[i].file is just used as a dummy buffer to save data, |
388 | * set its ops to empty. | |
56e93d26 JQ |
389 | */ |
390 | comp_param[i].file = qemu_fopen_ops(NULL, &empty_ops); | |
391 | comp_param[i].done = true; | |
90e56fb4 | 392 | comp_param[i].quit = false; |
56e93d26 JQ |
393 | qemu_mutex_init(&comp_param[i].mutex); |
394 | qemu_cond_init(&comp_param[i].cond); | |
395 | qemu_thread_create(compress_threads + i, "compress", | |
396 | do_data_compress, comp_param + i, | |
397 | QEMU_THREAD_JOINABLE); | |
398 | } | |
399 | } | |
400 | ||
401 | /** | |
3d0684b2 | 402 | * save_page_header: write page header to wire |
56e93d26 JQ |
403 | * |
404 | * If this is the 1st block, it also writes the block identification | |
405 | * | |
3d0684b2 | 406 | * Returns the number of bytes written |
56e93d26 JQ |
407 | * |
408 | * @f: QEMUFile where to send the data | |
409 | * @block: block that contains the page we want to send | |
410 | * @offset: offset inside the block for the page | |
411 | * in the lower bits, it contains flags | |
412 | */ | |
413 | static size_t save_page_header(QEMUFile *f, RAMBlock *block, ram_addr_t offset) | |
414 | { | |
9f5f380b | 415 | size_t size, len; |
56e93d26 JQ |
416 | |
417 | qemu_put_be64(f, offset); | |
418 | size = 8; | |
419 | ||
420 | if (!(offset & RAM_SAVE_FLAG_CONTINUE)) { | |
9f5f380b LL |
421 | len = strlen(block->idstr); |
422 | qemu_put_byte(f, len); | |
423 | qemu_put_buffer(f, (uint8_t *)block->idstr, len); | |
424 | size += 1 + len; | |
56e93d26 JQ |
425 | } |
426 | return size; | |
427 | } | |
428 | ||
3d0684b2 JQ |
429 | /** |
430 | * mig_throttle_guest_down: throotle down the guest | |
431 | * | |
432 | * Reduce amount of guest cpu execution to hopefully slow down memory | |
433 | * writes. If guest dirty memory rate is reduced below the rate at | |
434 | * which we can transfer pages to the destination then we should be | |
435 | * able to complete migration. Some workloads dirty memory way too | |
436 | * fast and will not effectively converge, even with auto-converge. | |
070afca2 JH |
437 | */ |
438 | static void mig_throttle_guest_down(void) | |
439 | { | |
440 | MigrationState *s = migrate_get_current(); | |
2594f56d DB |
441 | uint64_t pct_initial = s->parameters.cpu_throttle_initial; |
442 | uint64_t pct_icrement = s->parameters.cpu_throttle_increment; | |
070afca2 JH |
443 | |
444 | /* We have not started throttling yet. Let's start it. */ | |
445 | if (!cpu_throttle_active()) { | |
446 | cpu_throttle_set(pct_initial); | |
447 | } else { | |
448 | /* Throttling already on, just increase the rate */ | |
449 | cpu_throttle_set(cpu_throttle_get_percentage() + pct_icrement); | |
450 | } | |
451 | } | |
452 | ||
3d0684b2 JQ |
453 | /** |
454 | * xbzrle_cache_zero_page: insert a zero page in the XBZRLE cache | |
455 | * | |
6f37bb8b | 456 | * @rs: current RAM state |
3d0684b2 JQ |
457 | * @current_addr: address for the zero page |
458 | * | |
459 | * Update the xbzrle cache to reflect a page that's been sent as all 0. | |
56e93d26 JQ |
460 | * The important thing is that a stale (not-yet-0'd) page be replaced |
461 | * by the new data. | |
462 | * As a bonus, if the page wasn't in the cache it gets added so that | |
3d0684b2 | 463 | * when a small write is made into the 0'd page it gets XBZRLE sent. |
56e93d26 | 464 | */ |
6f37bb8b | 465 | static void xbzrle_cache_zero_page(RAMState *rs, ram_addr_t current_addr) |
56e93d26 | 466 | { |
6f37bb8b | 467 | if (rs->ram_bulk_stage || !migrate_use_xbzrle()) { |
56e93d26 JQ |
468 | return; |
469 | } | |
470 | ||
471 | /* We don't care if this fails to allocate a new cache page | |
472 | * as long as it updated an old one */ | |
473 | cache_insert(XBZRLE.cache, current_addr, ZERO_TARGET_PAGE, | |
474 | bitmap_sync_count); | |
475 | } | |
476 | ||
477 | #define ENCODING_FLAG_XBZRLE 0x1 | |
478 | ||
479 | /** | |
480 | * save_xbzrle_page: compress and send current page | |
481 | * | |
482 | * Returns: 1 means that we wrote the page | |
483 | * 0 means that page is identical to the one already sent | |
484 | * -1 means that xbzrle would be longer than normal | |
485 | * | |
486 | * @f: QEMUFile where to send the data | |
3d0684b2 JQ |
487 | * @current_data: pointer to the address of the page contents |
488 | * @current_addr: addr of the page | |
56e93d26 JQ |
489 | * @block: block that contains the page we want to send |
490 | * @offset: offset inside the block for the page | |
491 | * @last_stage: if we are at the completion stage | |
492 | * @bytes_transferred: increase it with the number of transferred bytes | |
493 | */ | |
494 | static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data, | |
495 | ram_addr_t current_addr, RAMBlock *block, | |
496 | ram_addr_t offset, bool last_stage, | |
497 | uint64_t *bytes_transferred) | |
498 | { | |
499 | int encoded_len = 0, bytes_xbzrle; | |
500 | uint8_t *prev_cached_page; | |
501 | ||
502 | if (!cache_is_cached(XBZRLE.cache, current_addr, bitmap_sync_count)) { | |
503 | acct_info.xbzrle_cache_miss++; | |
504 | if (!last_stage) { | |
505 | if (cache_insert(XBZRLE.cache, current_addr, *current_data, | |
506 | bitmap_sync_count) == -1) { | |
507 | return -1; | |
508 | } else { | |
509 | /* update *current_data when the page has been | |
510 | inserted into cache */ | |
511 | *current_data = get_cached_data(XBZRLE.cache, current_addr); | |
512 | } | |
513 | } | |
514 | return -1; | |
515 | } | |
516 | ||
517 | prev_cached_page = get_cached_data(XBZRLE.cache, current_addr); | |
518 | ||
519 | /* save current buffer into memory */ | |
520 | memcpy(XBZRLE.current_buf, *current_data, TARGET_PAGE_SIZE); | |
521 | ||
522 | /* XBZRLE encoding (if there is no overflow) */ | |
523 | encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf, | |
524 | TARGET_PAGE_SIZE, XBZRLE.encoded_buf, | |
525 | TARGET_PAGE_SIZE); | |
526 | if (encoded_len == 0) { | |
55c4446b | 527 | trace_save_xbzrle_page_skipping(); |
56e93d26 JQ |
528 | return 0; |
529 | } else if (encoded_len == -1) { | |
55c4446b | 530 | trace_save_xbzrle_page_overflow(); |
56e93d26 JQ |
531 | acct_info.xbzrle_overflows++; |
532 | /* update data in the cache */ | |
533 | if (!last_stage) { | |
534 | memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE); | |
535 | *current_data = prev_cached_page; | |
536 | } | |
537 | return -1; | |
538 | } | |
539 | ||
540 | /* we need to update the data in the cache, in order to get the same data */ | |
541 | if (!last_stage) { | |
542 | memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); | |
543 | } | |
544 | ||
545 | /* Send XBZRLE based compressed page */ | |
546 | bytes_xbzrle = save_page_header(f, block, offset | RAM_SAVE_FLAG_XBZRLE); | |
547 | qemu_put_byte(f, ENCODING_FLAG_XBZRLE); | |
548 | qemu_put_be16(f, encoded_len); | |
549 | qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len); | |
550 | bytes_xbzrle += encoded_len + 1 + 2; | |
551 | acct_info.xbzrle_pages++; | |
552 | acct_info.xbzrle_bytes += bytes_xbzrle; | |
553 | *bytes_transferred += bytes_xbzrle; | |
554 | ||
555 | return 1; | |
556 | } | |
557 | ||
3d0684b2 JQ |
558 | /** |
559 | * migration_bitmap_find_dirty: find the next dirty page from start | |
f3f491fc | 560 | * |
3d0684b2 JQ |
561 | * Called with rcu_read_lock() to protect migration_bitmap |
562 | * | |
563 | * Returns the byte offset within memory region of the start of a dirty page | |
564 | * | |
6f37bb8b | 565 | * @rs: current RAM state |
3d0684b2 JQ |
566 | * @rb: RAMBlock where to search for dirty pages |
567 | * @start: starting address (typically so we can continue from previous page) | |
568 | * @ram_addr_abs: pointer into which to store the address of the dirty page | |
569 | * within the global ram_addr space | |
f3f491fc | 570 | */ |
56e93d26 | 571 | static inline |
6f37bb8b | 572 | ram_addr_t migration_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, |
a82d593b DDAG |
573 | ram_addr_t start, |
574 | ram_addr_t *ram_addr_abs) | |
56e93d26 | 575 | { |
2f68e399 | 576 | unsigned long base = rb->offset >> TARGET_PAGE_BITS; |
56e93d26 | 577 | unsigned long nr = base + (start >> TARGET_PAGE_BITS); |
2f68e399 DDAG |
578 | uint64_t rb_size = rb->used_length; |
579 | unsigned long size = base + (rb_size >> TARGET_PAGE_BITS); | |
2ff64038 | 580 | unsigned long *bitmap; |
56e93d26 JQ |
581 | |
582 | unsigned long next; | |
583 | ||
60be6340 | 584 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
6f37bb8b | 585 | if (rs->ram_bulk_stage && nr > base) { |
56e93d26 JQ |
586 | next = nr + 1; |
587 | } else { | |
2ff64038 | 588 | next = find_next_bit(bitmap, size, nr); |
56e93d26 JQ |
589 | } |
590 | ||
f3f491fc | 591 | *ram_addr_abs = next << TARGET_PAGE_BITS; |
56e93d26 JQ |
592 | return (next - base) << TARGET_PAGE_BITS; |
593 | } | |
594 | ||
a82d593b DDAG |
595 | static inline bool migration_bitmap_clear_dirty(ram_addr_t addr) |
596 | { | |
597 | bool ret; | |
598 | int nr = addr >> TARGET_PAGE_BITS; | |
599 | unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; | |
600 | ||
601 | ret = test_and_clear_bit(nr, bitmap); | |
602 | ||
603 | if (ret) { | |
604 | migration_dirty_pages--; | |
605 | } | |
606 | return ret; | |
607 | } | |
608 | ||
1ffb5dfd | 609 | static int64_t num_dirty_pages_period; |
56e93d26 JQ |
610 | static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length) |
611 | { | |
2ff64038 | 612 | unsigned long *bitmap; |
60be6340 | 613 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
1ffb5dfd CF |
614 | migration_dirty_pages += cpu_physical_memory_sync_dirty_bitmap(bitmap, |
615 | start, length, &num_dirty_pages_period); | |
56e93d26 JQ |
616 | } |
617 | ||
56e93d26 JQ |
618 | /* Fix me: there are too many global variables used in migration process. */ |
619 | static int64_t start_time; | |
620 | static int64_t bytes_xfer_prev; | |
56e93d26 JQ |
621 | static uint64_t xbzrle_cache_miss_prev; |
622 | static uint64_t iterations_prev; | |
623 | ||
624 | static void migration_bitmap_sync_init(void) | |
625 | { | |
626 | start_time = 0; | |
627 | bytes_xfer_prev = 0; | |
628 | num_dirty_pages_period = 0; | |
629 | xbzrle_cache_miss_prev = 0; | |
630 | iterations_prev = 0; | |
631 | } | |
632 | ||
3d0684b2 JQ |
633 | /** |
634 | * ram_pagesize_summary: calculate all the pagesizes of a VM | |
635 | * | |
636 | * Returns a summary bitmap of the page sizes of all RAMBlocks | |
637 | * | |
638 | * For VMs with just normal pages this is equivalent to the host page | |
639 | * size. If it's got some huge pages then it's the OR of all the | |
640 | * different page sizes. | |
e8ca1db2 DDAG |
641 | */ |
642 | uint64_t ram_pagesize_summary(void) | |
643 | { | |
644 | RAMBlock *block; | |
645 | uint64_t summary = 0; | |
646 | ||
647 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
648 | summary |= block->page_size; | |
649 | } | |
650 | ||
651 | return summary; | |
652 | } | |
653 | ||
56e93d26 JQ |
654 | static void migration_bitmap_sync(void) |
655 | { | |
656 | RAMBlock *block; | |
56e93d26 JQ |
657 | MigrationState *s = migrate_get_current(); |
658 | int64_t end_time; | |
659 | int64_t bytes_xfer_now; | |
660 | ||
661 | bitmap_sync_count++; | |
662 | ||
663 | if (!bytes_xfer_prev) { | |
664 | bytes_xfer_prev = ram_bytes_transferred(); | |
665 | } | |
666 | ||
667 | if (!start_time) { | |
668 | start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); | |
669 | } | |
670 | ||
671 | trace_migration_bitmap_sync_start(); | |
9c1f8f44 | 672 | memory_global_dirty_log_sync(); |
56e93d26 | 673 | |
dd631697 | 674 | qemu_mutex_lock(&migration_bitmap_mutex); |
56e93d26 JQ |
675 | rcu_read_lock(); |
676 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
2f68e399 | 677 | migration_bitmap_sync_range(block->offset, block->used_length); |
56e93d26 JQ |
678 | } |
679 | rcu_read_unlock(); | |
dd631697 | 680 | qemu_mutex_unlock(&migration_bitmap_mutex); |
56e93d26 | 681 | |
1ffb5dfd CF |
682 | trace_migration_bitmap_sync_end(num_dirty_pages_period); |
683 | ||
56e93d26 JQ |
684 | end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); |
685 | ||
686 | /* more than 1 second = 1000 millisecons */ | |
687 | if (end_time > start_time + 1000) { | |
688 | if (migrate_auto_converge()) { | |
689 | /* The following detection logic can be refined later. For now: | |
690 | Check to see if the dirtied bytes is 50% more than the approx. | |
691 | amount of bytes that just got transferred since the last time we | |
070afca2 JH |
692 | were in this routine. If that happens twice, start or increase |
693 | throttling */ | |
56e93d26 | 694 | bytes_xfer_now = ram_bytes_transferred(); |
070afca2 | 695 | |
56e93d26 JQ |
696 | if (s->dirty_pages_rate && |
697 | (num_dirty_pages_period * TARGET_PAGE_SIZE > | |
698 | (bytes_xfer_now - bytes_xfer_prev)/2) && | |
070afca2 | 699 | (dirty_rate_high_cnt++ >= 2)) { |
56e93d26 | 700 | trace_migration_throttle(); |
56e93d26 | 701 | dirty_rate_high_cnt = 0; |
070afca2 | 702 | mig_throttle_guest_down(); |
56e93d26 JQ |
703 | } |
704 | bytes_xfer_prev = bytes_xfer_now; | |
56e93d26 | 705 | } |
070afca2 | 706 | |
56e93d26 JQ |
707 | if (migrate_use_xbzrle()) { |
708 | if (iterations_prev != acct_info.iterations) { | |
709 | acct_info.xbzrle_cache_miss_rate = | |
710 | (double)(acct_info.xbzrle_cache_miss - | |
711 | xbzrle_cache_miss_prev) / | |
712 | (acct_info.iterations - iterations_prev); | |
713 | } | |
714 | iterations_prev = acct_info.iterations; | |
715 | xbzrle_cache_miss_prev = acct_info.xbzrle_cache_miss; | |
716 | } | |
717 | s->dirty_pages_rate = num_dirty_pages_period * 1000 | |
718 | / (end_time - start_time); | |
719 | s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE; | |
720 | start_time = end_time; | |
721 | num_dirty_pages_period = 0; | |
722 | } | |
723 | s->dirty_sync_count = bitmap_sync_count; | |
4addcd4f DDAG |
724 | if (migrate_use_events()) { |
725 | qapi_event_send_migration_pass(bitmap_sync_count, NULL); | |
726 | } | |
56e93d26 JQ |
727 | } |
728 | ||
729 | /** | |
3d0684b2 | 730 | * save_zero_page: send the zero page to the stream |
56e93d26 | 731 | * |
3d0684b2 | 732 | * Returns the number of pages written. |
56e93d26 JQ |
733 | * |
734 | * @f: QEMUFile where to send the data | |
735 | * @block: block that contains the page we want to send | |
736 | * @offset: offset inside the block for the page | |
737 | * @p: pointer to the page | |
738 | * @bytes_transferred: increase it with the number of transferred bytes | |
739 | */ | |
740 | static int save_zero_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset, | |
741 | uint8_t *p, uint64_t *bytes_transferred) | |
742 | { | |
743 | int pages = -1; | |
744 | ||
745 | if (is_zero_range(p, TARGET_PAGE_SIZE)) { | |
746 | acct_info.dup_pages++; | |
747 | *bytes_transferred += save_page_header(f, block, | |
748 | offset | RAM_SAVE_FLAG_COMPRESS); | |
749 | qemu_put_byte(f, 0); | |
750 | *bytes_transferred += 1; | |
751 | pages = 1; | |
752 | } | |
753 | ||
754 | return pages; | |
755 | } | |
756 | ||
36449157 | 757 | static void ram_release_pages(MigrationState *ms, const char *rbname, |
53f09a10 PB |
758 | uint64_t offset, int pages) |
759 | { | |
760 | if (!migrate_release_ram() || !migration_in_postcopy(ms)) { | |
761 | return; | |
762 | } | |
763 | ||
36449157 | 764 | ram_discard_range(NULL, rbname, offset, pages << TARGET_PAGE_BITS); |
53f09a10 PB |
765 | } |
766 | ||
56e93d26 | 767 | /** |
3d0684b2 | 768 | * ram_save_page: send the given page to the stream |
56e93d26 | 769 | * |
3d0684b2 | 770 | * Returns the number of pages written. |
3fd3c4b3 DDAG |
771 | * < 0 - error |
772 | * >=0 - Number of pages written - this might legally be 0 | |
773 | * if xbzrle noticed the page was the same. | |
56e93d26 | 774 | * |
6f37bb8b | 775 | * @rs: current RAM state |
3d0684b2 | 776 | * @ms: current migration state |
56e93d26 JQ |
777 | * @f: QEMUFile where to send the data |
778 | * @block: block that contains the page we want to send | |
779 | * @offset: offset inside the block for the page | |
780 | * @last_stage: if we are at the completion stage | |
781 | * @bytes_transferred: increase it with the number of transferred bytes | |
782 | */ | |
6f37bb8b JQ |
783 | static int ram_save_page(RAMState *rs, MigrationState *ms, QEMUFile *f, |
784 | PageSearchStatus *pss, bool last_stage, | |
785 | uint64_t *bytes_transferred) | |
56e93d26 JQ |
786 | { |
787 | int pages = -1; | |
788 | uint64_t bytes_xmit; | |
789 | ram_addr_t current_addr; | |
56e93d26 JQ |
790 | uint8_t *p; |
791 | int ret; | |
792 | bool send_async = true; | |
a08f6890 HZ |
793 | RAMBlock *block = pss->block; |
794 | ram_addr_t offset = pss->offset; | |
56e93d26 | 795 | |
2f68e399 | 796 | p = block->host + offset; |
56e93d26 JQ |
797 | |
798 | /* In doubt sent page as normal */ | |
799 | bytes_xmit = 0; | |
800 | ret = ram_control_save_page(f, block->offset, | |
801 | offset, TARGET_PAGE_SIZE, &bytes_xmit); | |
802 | if (bytes_xmit) { | |
803 | *bytes_transferred += bytes_xmit; | |
804 | pages = 1; | |
805 | } | |
806 | ||
807 | XBZRLE_cache_lock(); | |
808 | ||
809 | current_addr = block->offset + offset; | |
810 | ||
6f37bb8b | 811 | if (block == rs->last_sent_block) { |
56e93d26 JQ |
812 | offset |= RAM_SAVE_FLAG_CONTINUE; |
813 | } | |
814 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { | |
815 | if (ret != RAM_SAVE_CONTROL_DELAYED) { | |
816 | if (bytes_xmit > 0) { | |
817 | acct_info.norm_pages++; | |
818 | } else if (bytes_xmit == 0) { | |
819 | acct_info.dup_pages++; | |
820 | } | |
821 | } | |
822 | } else { | |
823 | pages = save_zero_page(f, block, offset, p, bytes_transferred); | |
824 | if (pages > 0) { | |
825 | /* Must let xbzrle know, otherwise a previous (now 0'd) cached | |
826 | * page would be stale | |
827 | */ | |
6f37bb8b | 828 | xbzrle_cache_zero_page(rs, current_addr); |
53f09a10 | 829 | ram_release_pages(ms, block->idstr, pss->offset, pages); |
6f37bb8b | 830 | } else if (!rs->ram_bulk_stage && |
9eb14766 | 831 | !migration_in_postcopy(ms) && migrate_use_xbzrle()) { |
56e93d26 JQ |
832 | pages = save_xbzrle_page(f, &p, current_addr, block, |
833 | offset, last_stage, bytes_transferred); | |
834 | if (!last_stage) { | |
835 | /* Can't send this cached data async, since the cache page | |
836 | * might get updated before it gets to the wire | |
837 | */ | |
838 | send_async = false; | |
839 | } | |
840 | } | |
841 | } | |
842 | ||
843 | /* XBZRLE overflow or normal page */ | |
844 | if (pages == -1) { | |
845 | *bytes_transferred += save_page_header(f, block, | |
846 | offset | RAM_SAVE_FLAG_PAGE); | |
847 | if (send_async) { | |
53f09a10 PB |
848 | qemu_put_buffer_async(f, p, TARGET_PAGE_SIZE, |
849 | migrate_release_ram() & | |
850 | migration_in_postcopy(ms)); | |
56e93d26 JQ |
851 | } else { |
852 | qemu_put_buffer(f, p, TARGET_PAGE_SIZE); | |
853 | } | |
854 | *bytes_transferred += TARGET_PAGE_SIZE; | |
855 | pages = 1; | |
856 | acct_info.norm_pages++; | |
857 | } | |
858 | ||
859 | XBZRLE_cache_unlock(); | |
860 | ||
861 | return pages; | |
862 | } | |
863 | ||
a7a9a88f LL |
864 | static int do_compress_ram_page(QEMUFile *f, RAMBlock *block, |
865 | ram_addr_t offset) | |
56e93d26 JQ |
866 | { |
867 | int bytes_sent, blen; | |
a7a9a88f | 868 | uint8_t *p = block->host + (offset & TARGET_PAGE_MASK); |
56e93d26 | 869 | |
a7a9a88f | 870 | bytes_sent = save_page_header(f, block, offset | |
56e93d26 | 871 | RAM_SAVE_FLAG_COMPRESS_PAGE); |
a7a9a88f | 872 | blen = qemu_put_compression_data(f, p, TARGET_PAGE_SIZE, |
56e93d26 | 873 | migrate_compress_level()); |
b3be2896 LL |
874 | if (blen < 0) { |
875 | bytes_sent = 0; | |
876 | qemu_file_set_error(migrate_get_current()->to_dst_file, blen); | |
877 | error_report("compressed data failed!"); | |
878 | } else { | |
879 | bytes_sent += blen; | |
53f09a10 PB |
880 | ram_release_pages(migrate_get_current(), block->idstr, |
881 | offset & TARGET_PAGE_MASK, 1); | |
b3be2896 | 882 | } |
56e93d26 JQ |
883 | |
884 | return bytes_sent; | |
885 | } | |
886 | ||
56e93d26 JQ |
887 | static uint64_t bytes_transferred; |
888 | ||
889 | static void flush_compressed_data(QEMUFile *f) | |
890 | { | |
891 | int idx, len, thread_count; | |
892 | ||
893 | if (!migrate_use_compression()) { | |
894 | return; | |
895 | } | |
896 | thread_count = migrate_compress_threads(); | |
a7a9a88f | 897 | |
0d9f9a5c | 898 | qemu_mutex_lock(&comp_done_lock); |
56e93d26 | 899 | for (idx = 0; idx < thread_count; idx++) { |
a7a9a88f | 900 | while (!comp_param[idx].done) { |
0d9f9a5c | 901 | qemu_cond_wait(&comp_done_cond, &comp_done_lock); |
56e93d26 | 902 | } |
a7a9a88f | 903 | } |
0d9f9a5c | 904 | qemu_mutex_unlock(&comp_done_lock); |
a7a9a88f LL |
905 | |
906 | for (idx = 0; idx < thread_count; idx++) { | |
907 | qemu_mutex_lock(&comp_param[idx].mutex); | |
90e56fb4 | 908 | if (!comp_param[idx].quit) { |
56e93d26 JQ |
909 | len = qemu_put_qemu_file(f, comp_param[idx].file); |
910 | bytes_transferred += len; | |
911 | } | |
a7a9a88f | 912 | qemu_mutex_unlock(&comp_param[idx].mutex); |
56e93d26 JQ |
913 | } |
914 | } | |
915 | ||
916 | static inline void set_compress_params(CompressParam *param, RAMBlock *block, | |
917 | ram_addr_t offset) | |
918 | { | |
919 | param->block = block; | |
920 | param->offset = offset; | |
921 | } | |
922 | ||
923 | static int compress_page_with_multi_thread(QEMUFile *f, RAMBlock *block, | |
924 | ram_addr_t offset, | |
925 | uint64_t *bytes_transferred) | |
926 | { | |
927 | int idx, thread_count, bytes_xmit = -1, pages = -1; | |
928 | ||
929 | thread_count = migrate_compress_threads(); | |
0d9f9a5c | 930 | qemu_mutex_lock(&comp_done_lock); |
56e93d26 JQ |
931 | while (true) { |
932 | for (idx = 0; idx < thread_count; idx++) { | |
933 | if (comp_param[idx].done) { | |
a7a9a88f | 934 | comp_param[idx].done = false; |
56e93d26 | 935 | bytes_xmit = qemu_put_qemu_file(f, comp_param[idx].file); |
a7a9a88f | 936 | qemu_mutex_lock(&comp_param[idx].mutex); |
56e93d26 | 937 | set_compress_params(&comp_param[idx], block, offset); |
a7a9a88f LL |
938 | qemu_cond_signal(&comp_param[idx].cond); |
939 | qemu_mutex_unlock(&comp_param[idx].mutex); | |
56e93d26 JQ |
940 | pages = 1; |
941 | acct_info.norm_pages++; | |
942 | *bytes_transferred += bytes_xmit; | |
943 | break; | |
944 | } | |
945 | } | |
946 | if (pages > 0) { | |
947 | break; | |
948 | } else { | |
0d9f9a5c | 949 | qemu_cond_wait(&comp_done_cond, &comp_done_lock); |
56e93d26 JQ |
950 | } |
951 | } | |
0d9f9a5c | 952 | qemu_mutex_unlock(&comp_done_lock); |
56e93d26 JQ |
953 | |
954 | return pages; | |
955 | } | |
956 | ||
957 | /** | |
958 | * ram_save_compressed_page: compress the given page and send it to the stream | |
959 | * | |
3d0684b2 | 960 | * Returns the number of pages written. |
56e93d26 | 961 | * |
6f37bb8b | 962 | * @rs: current RAM state |
3d0684b2 | 963 | * @ms: current migration state |
56e93d26 JQ |
964 | * @f: QEMUFile where to send the data |
965 | * @block: block that contains the page we want to send | |
966 | * @offset: offset inside the block for the page | |
967 | * @last_stage: if we are at the completion stage | |
968 | * @bytes_transferred: increase it with the number of transferred bytes | |
969 | */ | |
6f37bb8b JQ |
970 | static int ram_save_compressed_page(RAMState *rs, MigrationState *ms, |
971 | QEMUFile *f, | |
9eb14766 | 972 | PageSearchStatus *pss, bool last_stage, |
56e93d26 JQ |
973 | uint64_t *bytes_transferred) |
974 | { | |
975 | int pages = -1; | |
fc50438e | 976 | uint64_t bytes_xmit = 0; |
56e93d26 | 977 | uint8_t *p; |
fc50438e | 978 | int ret, blen; |
a08f6890 HZ |
979 | RAMBlock *block = pss->block; |
980 | ram_addr_t offset = pss->offset; | |
56e93d26 | 981 | |
2f68e399 | 982 | p = block->host + offset; |
56e93d26 | 983 | |
56e93d26 JQ |
984 | ret = ram_control_save_page(f, block->offset, |
985 | offset, TARGET_PAGE_SIZE, &bytes_xmit); | |
986 | if (bytes_xmit) { | |
987 | *bytes_transferred += bytes_xmit; | |
988 | pages = 1; | |
989 | } | |
56e93d26 JQ |
990 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
991 | if (ret != RAM_SAVE_CONTROL_DELAYED) { | |
992 | if (bytes_xmit > 0) { | |
993 | acct_info.norm_pages++; | |
994 | } else if (bytes_xmit == 0) { | |
995 | acct_info.dup_pages++; | |
996 | } | |
997 | } | |
998 | } else { | |
999 | /* When starting the process of a new block, the first page of | |
1000 | * the block should be sent out before other pages in the same | |
1001 | * block, and all the pages in last block should have been sent | |
1002 | * out, keeping this order is important, because the 'cont' flag | |
1003 | * is used to avoid resending the block name. | |
1004 | */ | |
6f37bb8b | 1005 | if (block != rs->last_sent_block) { |
56e93d26 JQ |
1006 | flush_compressed_data(f); |
1007 | pages = save_zero_page(f, block, offset, p, bytes_transferred); | |
1008 | if (pages == -1) { | |
fc50438e LL |
1009 | /* Make sure the first page is sent out before other pages */ |
1010 | bytes_xmit = save_page_header(f, block, offset | | |
1011 | RAM_SAVE_FLAG_COMPRESS_PAGE); | |
1012 | blen = qemu_put_compression_data(f, p, TARGET_PAGE_SIZE, | |
1013 | migrate_compress_level()); | |
1014 | if (blen > 0) { | |
1015 | *bytes_transferred += bytes_xmit + blen; | |
b3be2896 | 1016 | acct_info.norm_pages++; |
b3be2896 | 1017 | pages = 1; |
fc50438e LL |
1018 | } else { |
1019 | qemu_file_set_error(f, blen); | |
1020 | error_report("compressed data failed!"); | |
b3be2896 | 1021 | } |
56e93d26 | 1022 | } |
53f09a10 PB |
1023 | if (pages > 0) { |
1024 | ram_release_pages(ms, block->idstr, pss->offset, pages); | |
1025 | } | |
56e93d26 | 1026 | } else { |
fc50438e | 1027 | offset |= RAM_SAVE_FLAG_CONTINUE; |
56e93d26 JQ |
1028 | pages = save_zero_page(f, block, offset, p, bytes_transferred); |
1029 | if (pages == -1) { | |
1030 | pages = compress_page_with_multi_thread(f, block, offset, | |
1031 | bytes_transferred); | |
53f09a10 PB |
1032 | } else { |
1033 | ram_release_pages(ms, block->idstr, pss->offset, pages); | |
56e93d26 JQ |
1034 | } |
1035 | } | |
1036 | } | |
1037 | ||
1038 | return pages; | |
1039 | } | |
1040 | ||
3d0684b2 JQ |
1041 | /** |
1042 | * find_dirty_block: find the next dirty page and update any state | |
1043 | * associated with the search process. | |
b9e60928 | 1044 | * |
3d0684b2 | 1045 | * Returns if a page is found |
b9e60928 | 1046 | * |
6f37bb8b | 1047 | * @rs: current RAM state |
3d0684b2 JQ |
1048 | * @f: QEMUFile where to send the data |
1049 | * @pss: data about the state of the current dirty page scan | |
1050 | * @again: set to false if the search has scanned the whole of RAM | |
1051 | * @ram_addr_abs: pointer into which to store the address of the dirty page | |
1052 | * within the global ram_addr space | |
b9e60928 | 1053 | */ |
6f37bb8b | 1054 | static bool find_dirty_block(RAMState *rs, QEMUFile *f, PageSearchStatus *pss, |
f3f491fc | 1055 | bool *again, ram_addr_t *ram_addr_abs) |
b9e60928 | 1056 | { |
6f37bb8b | 1057 | pss->offset = migration_bitmap_find_dirty(rs, pss->block, pss->offset, |
a82d593b | 1058 | ram_addr_abs); |
6f37bb8b JQ |
1059 | if (pss->complete_round && pss->block == rs->last_seen_block && |
1060 | pss->offset >= rs->last_offset) { | |
b9e60928 DDAG |
1061 | /* |
1062 | * We've been once around the RAM and haven't found anything. | |
1063 | * Give up. | |
1064 | */ | |
1065 | *again = false; | |
1066 | return false; | |
1067 | } | |
1068 | if (pss->offset >= pss->block->used_length) { | |
1069 | /* Didn't find anything in this RAM Block */ | |
1070 | pss->offset = 0; | |
1071 | pss->block = QLIST_NEXT_RCU(pss->block, next); | |
1072 | if (!pss->block) { | |
1073 | /* Hit the end of the list */ | |
1074 | pss->block = QLIST_FIRST_RCU(&ram_list.blocks); | |
1075 | /* Flag that we've looped */ | |
1076 | pss->complete_round = true; | |
6f37bb8b | 1077 | rs->ram_bulk_stage = false; |
b9e60928 DDAG |
1078 | if (migrate_use_xbzrle()) { |
1079 | /* If xbzrle is on, stop using the data compression at this | |
1080 | * point. In theory, xbzrle can do better than compression. | |
1081 | */ | |
1082 | flush_compressed_data(f); | |
1083 | compression_switch = false; | |
1084 | } | |
1085 | } | |
1086 | /* Didn't find anything this time, but try again on the new block */ | |
1087 | *again = true; | |
1088 | return false; | |
1089 | } else { | |
1090 | /* Can go around again, but... */ | |
1091 | *again = true; | |
1092 | /* We've found something so probably don't need to */ | |
1093 | return true; | |
1094 | } | |
1095 | } | |
1096 | ||
3d0684b2 JQ |
1097 | /** |
1098 | * unqueue_page: gets a page of the queue | |
1099 | * | |
a82d593b | 1100 | * Helper for 'get_queued_page' - gets a page off the queue |
a82d593b | 1101 | * |
3d0684b2 JQ |
1102 | * Returns the block of the page (or NULL if none available) |
1103 | * | |
1104 | * @ms: current migration state | |
1105 | * @offset: used to return the offset within the RAMBlock | |
1106 | * @ram_addr_abs: pointer into which to store the address of the dirty page | |
1107 | * within the global ram_addr space | |
a82d593b DDAG |
1108 | */ |
1109 | static RAMBlock *unqueue_page(MigrationState *ms, ram_addr_t *offset, | |
1110 | ram_addr_t *ram_addr_abs) | |
1111 | { | |
1112 | RAMBlock *block = NULL; | |
1113 | ||
1114 | qemu_mutex_lock(&ms->src_page_req_mutex); | |
1115 | if (!QSIMPLEQ_EMPTY(&ms->src_page_requests)) { | |
1116 | struct MigrationSrcPageRequest *entry = | |
1117 | QSIMPLEQ_FIRST(&ms->src_page_requests); | |
1118 | block = entry->rb; | |
1119 | *offset = entry->offset; | |
1120 | *ram_addr_abs = (entry->offset + entry->rb->offset) & | |
1121 | TARGET_PAGE_MASK; | |
1122 | ||
1123 | if (entry->len > TARGET_PAGE_SIZE) { | |
1124 | entry->len -= TARGET_PAGE_SIZE; | |
1125 | entry->offset += TARGET_PAGE_SIZE; | |
1126 | } else { | |
1127 | memory_region_unref(block->mr); | |
1128 | QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req); | |
1129 | g_free(entry); | |
1130 | } | |
1131 | } | |
1132 | qemu_mutex_unlock(&ms->src_page_req_mutex); | |
1133 | ||
1134 | return block; | |
1135 | } | |
1136 | ||
3d0684b2 JQ |
1137 | /** |
1138 | * get_queued_page: unqueue a page from the postocpy requests | |
1139 | * | |
1140 | * Skips pages that are already sent (!dirty) | |
a82d593b | 1141 | * |
3d0684b2 | 1142 | * Returns if a queued page is found |
a82d593b | 1143 | * |
6f37bb8b | 1144 | * @rs: current RAM state |
3d0684b2 JQ |
1145 | * @ms: current migration state |
1146 | * @pss: data about the state of the current dirty page scan | |
1147 | * @ram_addr_abs: pointer into which to store the address of the dirty page | |
1148 | * within the global ram_addr space | |
a82d593b | 1149 | */ |
6f37bb8b JQ |
1150 | static bool get_queued_page(RAMState *rs, MigrationState *ms, |
1151 | PageSearchStatus *pss, | |
a82d593b DDAG |
1152 | ram_addr_t *ram_addr_abs) |
1153 | { | |
1154 | RAMBlock *block; | |
1155 | ram_addr_t offset; | |
1156 | bool dirty; | |
1157 | ||
1158 | do { | |
1159 | block = unqueue_page(ms, &offset, ram_addr_abs); | |
1160 | /* | |
1161 | * We're sending this page, and since it's postcopy nothing else | |
1162 | * will dirty it, and we must make sure it doesn't get sent again | |
1163 | * even if this queue request was received after the background | |
1164 | * search already sent it. | |
1165 | */ | |
1166 | if (block) { | |
1167 | unsigned long *bitmap; | |
1168 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; | |
1169 | dirty = test_bit(*ram_addr_abs >> TARGET_PAGE_BITS, bitmap); | |
1170 | if (!dirty) { | |
1171 | trace_get_queued_page_not_dirty( | |
1172 | block->idstr, (uint64_t)offset, | |
1173 | (uint64_t)*ram_addr_abs, | |
1174 | test_bit(*ram_addr_abs >> TARGET_PAGE_BITS, | |
1175 | atomic_rcu_read(&migration_bitmap_rcu)->unsentmap)); | |
1176 | } else { | |
1177 | trace_get_queued_page(block->idstr, | |
1178 | (uint64_t)offset, | |
1179 | (uint64_t)*ram_addr_abs); | |
1180 | } | |
1181 | } | |
1182 | ||
1183 | } while (block && !dirty); | |
1184 | ||
1185 | if (block) { | |
1186 | /* | |
1187 | * As soon as we start servicing pages out of order, then we have | |
1188 | * to kill the bulk stage, since the bulk stage assumes | |
1189 | * in (migration_bitmap_find_and_reset_dirty) that every page is | |
1190 | * dirty, that's no longer true. | |
1191 | */ | |
6f37bb8b | 1192 | rs->ram_bulk_stage = false; |
a82d593b DDAG |
1193 | |
1194 | /* | |
1195 | * We want the background search to continue from the queued page | |
1196 | * since the guest is likely to want other pages near to the page | |
1197 | * it just requested. | |
1198 | */ | |
1199 | pss->block = block; | |
1200 | pss->offset = offset; | |
1201 | } | |
1202 | ||
1203 | return !!block; | |
1204 | } | |
1205 | ||
6c595cde | 1206 | /** |
5e58f968 JQ |
1207 | * migration_page_queue_free: drop any remaining pages in the ram |
1208 | * request queue | |
6c595cde | 1209 | * |
3d0684b2 JQ |
1210 | * It should be empty at the end anyway, but in error cases there may |
1211 | * be some left. in case that there is any page left, we drop it. | |
1212 | * | |
1213 | * @ms: current migration state | |
6c595cde | 1214 | */ |
5e58f968 | 1215 | void migration_page_queue_free(MigrationState *ms) |
6c595cde DDAG |
1216 | { |
1217 | struct MigrationSrcPageRequest *mspr, *next_mspr; | |
1218 | /* This queue generally should be empty - but in the case of a failed | |
1219 | * migration might have some droppings in. | |
1220 | */ | |
1221 | rcu_read_lock(); | |
1222 | QSIMPLEQ_FOREACH_SAFE(mspr, &ms->src_page_requests, next_req, next_mspr) { | |
1223 | memory_region_unref(mspr->rb->mr); | |
1224 | QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req); | |
1225 | g_free(mspr); | |
1226 | } | |
1227 | rcu_read_unlock(); | |
1228 | } | |
1229 | ||
1230 | /** | |
3d0684b2 JQ |
1231 | * ram_save_queue_pages: queue the page for transmission |
1232 | * | |
1233 | * A request from postcopy destination for example. | |
1234 | * | |
1235 | * Returns zero on success or negative on error | |
1236 | * | |
1237 | * @ms: current migration state | |
1238 | * @rbname: Name of the RAMBLock of the request. NULL means the | |
1239 | * same that last one. | |
1240 | * @start: starting address from the start of the RAMBlock | |
1241 | * @len: length (in bytes) to send | |
6c595cde DDAG |
1242 | */ |
1243 | int ram_save_queue_pages(MigrationState *ms, const char *rbname, | |
1244 | ram_addr_t start, ram_addr_t len) | |
1245 | { | |
1246 | RAMBlock *ramblock; | |
1247 | ||
d3bf5418 | 1248 | ms->postcopy_requests++; |
6c595cde DDAG |
1249 | rcu_read_lock(); |
1250 | if (!rbname) { | |
1251 | /* Reuse last RAMBlock */ | |
1252 | ramblock = ms->last_req_rb; | |
1253 | ||
1254 | if (!ramblock) { | |
1255 | /* | |
1256 | * Shouldn't happen, we can't reuse the last RAMBlock if | |
1257 | * it's the 1st request. | |
1258 | */ | |
1259 | error_report("ram_save_queue_pages no previous block"); | |
1260 | goto err; | |
1261 | } | |
1262 | } else { | |
1263 | ramblock = qemu_ram_block_by_name(rbname); | |
1264 | ||
1265 | if (!ramblock) { | |
1266 | /* We shouldn't be asked for a non-existent RAMBlock */ | |
1267 | error_report("ram_save_queue_pages no block '%s'", rbname); | |
1268 | goto err; | |
1269 | } | |
1270 | ms->last_req_rb = ramblock; | |
1271 | } | |
1272 | trace_ram_save_queue_pages(ramblock->idstr, start, len); | |
1273 | if (start+len > ramblock->used_length) { | |
9458ad6b JQ |
1274 | error_report("%s request overrun start=" RAM_ADDR_FMT " len=" |
1275 | RAM_ADDR_FMT " blocklen=" RAM_ADDR_FMT, | |
6c595cde DDAG |
1276 | __func__, start, len, ramblock->used_length); |
1277 | goto err; | |
1278 | } | |
1279 | ||
1280 | struct MigrationSrcPageRequest *new_entry = | |
1281 | g_malloc0(sizeof(struct MigrationSrcPageRequest)); | |
1282 | new_entry->rb = ramblock; | |
1283 | new_entry->offset = start; | |
1284 | new_entry->len = len; | |
1285 | ||
1286 | memory_region_ref(ramblock->mr); | |
1287 | qemu_mutex_lock(&ms->src_page_req_mutex); | |
1288 | QSIMPLEQ_INSERT_TAIL(&ms->src_page_requests, new_entry, next_req); | |
1289 | qemu_mutex_unlock(&ms->src_page_req_mutex); | |
1290 | rcu_read_unlock(); | |
1291 | ||
1292 | return 0; | |
1293 | ||
1294 | err: | |
1295 | rcu_read_unlock(); | |
1296 | return -1; | |
1297 | } | |
1298 | ||
a82d593b | 1299 | /** |
3d0684b2 | 1300 | * ram_save_target_page: save one target page |
a82d593b | 1301 | * |
3d0684b2 | 1302 | * Returns the number of pages written |
a82d593b | 1303 | * |
6f37bb8b | 1304 | * @rs: current RAM state |
3d0684b2 | 1305 | * @ms: current migration state |
a82d593b | 1306 | * @f: QEMUFile where to send the data |
3d0684b2 | 1307 | * @pss: data about the page we want to send |
a82d593b DDAG |
1308 | * @last_stage: if we are at the completion stage |
1309 | * @bytes_transferred: increase it with the number of transferred bytes | |
3d0684b2 | 1310 | * @dirty_ram_abs: address of the start of the dirty page in ram_addr_t space |
a82d593b | 1311 | */ |
6f37bb8b | 1312 | static int ram_save_target_page(RAMState *rs, MigrationState *ms, QEMUFile *f, |
a08f6890 | 1313 | PageSearchStatus *pss, |
a82d593b DDAG |
1314 | bool last_stage, |
1315 | uint64_t *bytes_transferred, | |
1316 | ram_addr_t dirty_ram_abs) | |
1317 | { | |
1318 | int res = 0; | |
1319 | ||
1320 | /* Check the pages is dirty and if it is send it */ | |
1321 | if (migration_bitmap_clear_dirty(dirty_ram_abs)) { | |
1322 | unsigned long *unsentmap; | |
1323 | if (compression_switch && migrate_use_compression()) { | |
6f37bb8b | 1324 | res = ram_save_compressed_page(rs, ms, f, pss, |
a82d593b DDAG |
1325 | last_stage, |
1326 | bytes_transferred); | |
1327 | } else { | |
6f37bb8b | 1328 | res = ram_save_page(rs, ms, f, pss, last_stage, |
a82d593b DDAG |
1329 | bytes_transferred); |
1330 | } | |
1331 | ||
1332 | if (res < 0) { | |
1333 | return res; | |
1334 | } | |
1335 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; | |
1336 | if (unsentmap) { | |
1337 | clear_bit(dirty_ram_abs >> TARGET_PAGE_BITS, unsentmap); | |
1338 | } | |
3fd3c4b3 DDAG |
1339 | /* Only update last_sent_block if a block was actually sent; xbzrle |
1340 | * might have decided the page was identical so didn't bother writing | |
1341 | * to the stream. | |
1342 | */ | |
1343 | if (res > 0) { | |
6f37bb8b | 1344 | rs->last_sent_block = pss->block; |
3fd3c4b3 | 1345 | } |
a82d593b DDAG |
1346 | } |
1347 | ||
1348 | return res; | |
1349 | } | |
1350 | ||
1351 | /** | |
3d0684b2 | 1352 | * ram_save_host_page: save a whole host page |
a82d593b | 1353 | * |
3d0684b2 JQ |
1354 | * Starting at *offset send pages up to the end of the current host |
1355 | * page. It's valid for the initial offset to point into the middle of | |
1356 | * a host page in which case the remainder of the hostpage is sent. | |
1357 | * Only dirty target pages are sent. Note that the host page size may | |
1358 | * be a huge page for this block. | |
a82d593b | 1359 | * |
3d0684b2 JQ |
1360 | * Returns the number of pages written or negative on error |
1361 | * | |
6f37bb8b | 1362 | * @rs: current RAM state |
3d0684b2 | 1363 | * @ms: current migration state |
a82d593b | 1364 | * @f: QEMUFile where to send the data |
3d0684b2 | 1365 | * @pss: data about the page we want to send |
a82d593b DDAG |
1366 | * @last_stage: if we are at the completion stage |
1367 | * @bytes_transferred: increase it with the number of transferred bytes | |
1368 | * @dirty_ram_abs: Address of the start of the dirty page in ram_addr_t space | |
1369 | */ | |
6f37bb8b | 1370 | static int ram_save_host_page(RAMState *rs, MigrationState *ms, QEMUFile *f, |
a08f6890 HZ |
1371 | PageSearchStatus *pss, |
1372 | bool last_stage, | |
a82d593b DDAG |
1373 | uint64_t *bytes_transferred, |
1374 | ram_addr_t dirty_ram_abs) | |
1375 | { | |
1376 | int tmppages, pages = 0; | |
4c011c37 DDAG |
1377 | size_t pagesize = qemu_ram_pagesize(pss->block); |
1378 | ||
a82d593b | 1379 | do { |
6f37bb8b | 1380 | tmppages = ram_save_target_page(rs, ms, f, pss, last_stage, |
a82d593b DDAG |
1381 | bytes_transferred, dirty_ram_abs); |
1382 | if (tmppages < 0) { | |
1383 | return tmppages; | |
1384 | } | |
1385 | ||
1386 | pages += tmppages; | |
a08f6890 | 1387 | pss->offset += TARGET_PAGE_SIZE; |
a82d593b | 1388 | dirty_ram_abs += TARGET_PAGE_SIZE; |
4c011c37 | 1389 | } while (pss->offset & (pagesize - 1)); |
a82d593b DDAG |
1390 | |
1391 | /* The offset we leave with is the last one we looked at */ | |
a08f6890 | 1392 | pss->offset -= TARGET_PAGE_SIZE; |
a82d593b DDAG |
1393 | return pages; |
1394 | } | |
6c595cde | 1395 | |
56e93d26 | 1396 | /** |
3d0684b2 | 1397 | * ram_find_and_save_block: finds a dirty page and sends it to f |
56e93d26 JQ |
1398 | * |
1399 | * Called within an RCU critical section. | |
1400 | * | |
3d0684b2 | 1401 | * Returns the number of pages written where zero means no dirty pages |
56e93d26 | 1402 | * |
6f37bb8b | 1403 | * @rs: current RAM state |
56e93d26 JQ |
1404 | * @f: QEMUFile where to send the data |
1405 | * @last_stage: if we are at the completion stage | |
1406 | * @bytes_transferred: increase it with the number of transferred bytes | |
a82d593b DDAG |
1407 | * |
1408 | * On systems where host-page-size > target-page-size it will send all the | |
1409 | * pages in a host page that are dirty. | |
56e93d26 JQ |
1410 | */ |
1411 | ||
6f37bb8b | 1412 | static int ram_find_and_save_block(RAMState *rs, QEMUFile *f, bool last_stage, |
56e93d26 JQ |
1413 | uint64_t *bytes_transferred) |
1414 | { | |
b8fb8cb7 | 1415 | PageSearchStatus pss; |
a82d593b | 1416 | MigrationState *ms = migrate_get_current(); |
56e93d26 | 1417 | int pages = 0; |
b9e60928 | 1418 | bool again, found; |
f3f491fc DDAG |
1419 | ram_addr_t dirty_ram_abs; /* Address of the start of the dirty page in |
1420 | ram_addr_t space */ | |
56e93d26 | 1421 | |
0827b9e9 AA |
1422 | /* No dirty page as there is zero RAM */ |
1423 | if (!ram_bytes_total()) { | |
1424 | return pages; | |
1425 | } | |
1426 | ||
6f37bb8b JQ |
1427 | pss.block = rs->last_seen_block; |
1428 | pss.offset = rs->last_offset; | |
b8fb8cb7 DDAG |
1429 | pss.complete_round = false; |
1430 | ||
1431 | if (!pss.block) { | |
1432 | pss.block = QLIST_FIRST_RCU(&ram_list.blocks); | |
1433 | } | |
56e93d26 | 1434 | |
b9e60928 | 1435 | do { |
a82d593b | 1436 | again = true; |
6f37bb8b | 1437 | found = get_queued_page(rs, ms, &pss, &dirty_ram_abs); |
b9e60928 | 1438 | |
a82d593b DDAG |
1439 | if (!found) { |
1440 | /* priority queue empty, so just search for something dirty */ | |
6f37bb8b | 1441 | found = find_dirty_block(rs, f, &pss, &again, &dirty_ram_abs); |
a82d593b | 1442 | } |
f3f491fc | 1443 | |
a82d593b | 1444 | if (found) { |
6f37bb8b | 1445 | pages = ram_save_host_page(rs, ms, f, &pss, |
a82d593b DDAG |
1446 | last_stage, bytes_transferred, |
1447 | dirty_ram_abs); | |
56e93d26 | 1448 | } |
b9e60928 | 1449 | } while (!pages && again); |
56e93d26 | 1450 | |
6f37bb8b JQ |
1451 | rs->last_seen_block = pss.block; |
1452 | rs->last_offset = pss.offset; | |
56e93d26 JQ |
1453 | |
1454 | return pages; | |
1455 | } | |
1456 | ||
1457 | void acct_update_position(QEMUFile *f, size_t size, bool zero) | |
1458 | { | |
1459 | uint64_t pages = size / TARGET_PAGE_SIZE; | |
1460 | if (zero) { | |
1461 | acct_info.dup_pages += pages; | |
1462 | } else { | |
1463 | acct_info.norm_pages += pages; | |
1464 | bytes_transferred += size; | |
1465 | qemu_update_position(f, size); | |
1466 | } | |
1467 | } | |
1468 | ||
1469 | static ram_addr_t ram_save_remaining(void) | |
1470 | { | |
1471 | return migration_dirty_pages; | |
1472 | } | |
1473 | ||
1474 | uint64_t ram_bytes_remaining(void) | |
1475 | { | |
1476 | return ram_save_remaining() * TARGET_PAGE_SIZE; | |
1477 | } | |
1478 | ||
1479 | uint64_t ram_bytes_transferred(void) | |
1480 | { | |
1481 | return bytes_transferred; | |
1482 | } | |
1483 | ||
1484 | uint64_t ram_bytes_total(void) | |
1485 | { | |
1486 | RAMBlock *block; | |
1487 | uint64_t total = 0; | |
1488 | ||
1489 | rcu_read_lock(); | |
1490 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) | |
1491 | total += block->used_length; | |
1492 | rcu_read_unlock(); | |
1493 | return total; | |
1494 | } | |
1495 | ||
1496 | void free_xbzrle_decoded_buf(void) | |
1497 | { | |
1498 | g_free(xbzrle_decoded_buf); | |
1499 | xbzrle_decoded_buf = NULL; | |
1500 | } | |
1501 | ||
60be6340 DL |
1502 | static void migration_bitmap_free(struct BitmapRcu *bmap) |
1503 | { | |
1504 | g_free(bmap->bmap); | |
f3f491fc | 1505 | g_free(bmap->unsentmap); |
60be6340 DL |
1506 | g_free(bmap); |
1507 | } | |
1508 | ||
6ad2a215 | 1509 | static void ram_migration_cleanup(void *opaque) |
56e93d26 | 1510 | { |
2ff64038 LZ |
1511 | /* caller have hold iothread lock or is in a bh, so there is |
1512 | * no writing race against this migration_bitmap | |
1513 | */ | |
60be6340 DL |
1514 | struct BitmapRcu *bitmap = migration_bitmap_rcu; |
1515 | atomic_rcu_set(&migration_bitmap_rcu, NULL); | |
2ff64038 | 1516 | if (bitmap) { |
56e93d26 | 1517 | memory_global_dirty_log_stop(); |
60be6340 | 1518 | call_rcu(bitmap, migration_bitmap_free, rcu); |
56e93d26 JQ |
1519 | } |
1520 | ||
1521 | XBZRLE_cache_lock(); | |
1522 | if (XBZRLE.cache) { | |
1523 | cache_fini(XBZRLE.cache); | |
1524 | g_free(XBZRLE.encoded_buf); | |
1525 | g_free(XBZRLE.current_buf); | |
adb65dec | 1526 | g_free(ZERO_TARGET_PAGE); |
56e93d26 JQ |
1527 | XBZRLE.cache = NULL; |
1528 | XBZRLE.encoded_buf = NULL; | |
1529 | XBZRLE.current_buf = NULL; | |
1530 | } | |
1531 | XBZRLE_cache_unlock(); | |
1532 | } | |
1533 | ||
6f37bb8b | 1534 | static void ram_state_reset(RAMState *rs) |
56e93d26 | 1535 | { |
6f37bb8b JQ |
1536 | rs->last_seen_block = NULL; |
1537 | rs->last_sent_block = NULL; | |
1538 | rs->last_offset = 0; | |
1539 | rs->last_version = ram_list.version; | |
1540 | rs->ram_bulk_stage = true; | |
56e93d26 JQ |
1541 | } |
1542 | ||
1543 | #define MAX_WAIT 50 /* ms, half buffered_file limit */ | |
1544 | ||
dd631697 LZ |
1545 | void migration_bitmap_extend(ram_addr_t old, ram_addr_t new) |
1546 | { | |
1547 | /* called in qemu main thread, so there is | |
1548 | * no writing race against this migration_bitmap | |
1549 | */ | |
60be6340 DL |
1550 | if (migration_bitmap_rcu) { |
1551 | struct BitmapRcu *old_bitmap = migration_bitmap_rcu, *bitmap; | |
1552 | bitmap = g_new(struct BitmapRcu, 1); | |
1553 | bitmap->bmap = bitmap_new(new); | |
dd631697 LZ |
1554 | |
1555 | /* prevent migration_bitmap content from being set bit | |
1556 | * by migration_bitmap_sync_range() at the same time. | |
1557 | * it is safe to migration if migration_bitmap is cleared bit | |
1558 | * at the same time. | |
1559 | */ | |
1560 | qemu_mutex_lock(&migration_bitmap_mutex); | |
60be6340 DL |
1561 | bitmap_copy(bitmap->bmap, old_bitmap->bmap, old); |
1562 | bitmap_set(bitmap->bmap, old, new - old); | |
f3f491fc DDAG |
1563 | |
1564 | /* We don't have a way to safely extend the sentmap | |
1565 | * with RCU; so mark it as missing, entry to postcopy | |
1566 | * will fail. | |
1567 | */ | |
1568 | bitmap->unsentmap = NULL; | |
1569 | ||
60be6340 | 1570 | atomic_rcu_set(&migration_bitmap_rcu, bitmap); |
dd631697 LZ |
1571 | qemu_mutex_unlock(&migration_bitmap_mutex); |
1572 | migration_dirty_pages += new - old; | |
60be6340 | 1573 | call_rcu(old_bitmap, migration_bitmap_free, rcu); |
dd631697 LZ |
1574 | } |
1575 | } | |
56e93d26 | 1576 | |
4f2e4252 DDAG |
1577 | /* |
1578 | * 'expected' is the value you expect the bitmap mostly to be full | |
1579 | * of; it won't bother printing lines that are all this value. | |
1580 | * If 'todump' is null the migration bitmap is dumped. | |
1581 | */ | |
1582 | void ram_debug_dump_bitmap(unsigned long *todump, bool expected) | |
1583 | { | |
1584 | int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; | |
1585 | ||
1586 | int64_t cur; | |
1587 | int64_t linelen = 128; | |
1588 | char linebuf[129]; | |
1589 | ||
1590 | if (!todump) { | |
1591 | todump = atomic_rcu_read(&migration_bitmap_rcu)->bmap; | |
1592 | } | |
1593 | ||
1594 | for (cur = 0; cur < ram_pages; cur += linelen) { | |
1595 | int64_t curb; | |
1596 | bool found = false; | |
1597 | /* | |
1598 | * Last line; catch the case where the line length | |
1599 | * is longer than remaining ram | |
1600 | */ | |
1601 | if (cur + linelen > ram_pages) { | |
1602 | linelen = ram_pages - cur; | |
1603 | } | |
1604 | for (curb = 0; curb < linelen; curb++) { | |
1605 | bool thisbit = test_bit(cur + curb, todump); | |
1606 | linebuf[curb] = thisbit ? '1' : '.'; | |
1607 | found = found || (thisbit != expected); | |
1608 | } | |
1609 | if (found) { | |
1610 | linebuf[curb] = '\0'; | |
1611 | fprintf(stderr, "0x%08" PRIx64 " : %s\n", cur, linebuf); | |
1612 | } | |
1613 | } | |
1614 | } | |
1615 | ||
e0b266f0 DDAG |
1616 | /* **** functions for postcopy ***** */ |
1617 | ||
ced1c616 PB |
1618 | void ram_postcopy_migrated_memory_release(MigrationState *ms) |
1619 | { | |
1620 | struct RAMBlock *block; | |
1621 | unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; | |
1622 | ||
1623 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
1624 | unsigned long first = block->offset >> TARGET_PAGE_BITS; | |
1625 | unsigned long range = first + (block->used_length >> TARGET_PAGE_BITS); | |
1626 | unsigned long run_start = find_next_zero_bit(bitmap, range, first); | |
1627 | ||
1628 | while (run_start < range) { | |
1629 | unsigned long run_end = find_next_bit(bitmap, range, run_start + 1); | |
1630 | ram_discard_range(NULL, block->idstr, run_start << TARGET_PAGE_BITS, | |
1631 | (run_end - run_start) << TARGET_PAGE_BITS); | |
1632 | run_start = find_next_zero_bit(bitmap, range, run_end + 1); | |
1633 | } | |
1634 | } | |
1635 | } | |
1636 | ||
3d0684b2 JQ |
1637 | /** |
1638 | * postcopy_send_discard_bm_ram: discard a RAMBlock | |
1639 | * | |
1640 | * Returns zero on success | |
1641 | * | |
e0b266f0 DDAG |
1642 | * Callback from postcopy_each_ram_send_discard for each RAMBlock |
1643 | * Note: At this point the 'unsentmap' is the processed bitmap combined | |
1644 | * with the dirtymap; so a '1' means it's either dirty or unsent. | |
3d0684b2 JQ |
1645 | * |
1646 | * @ms: current migration state | |
1647 | * @pds: state for postcopy | |
1648 | * @start: RAMBlock starting page | |
1649 | * @length: RAMBlock size | |
e0b266f0 DDAG |
1650 | */ |
1651 | static int postcopy_send_discard_bm_ram(MigrationState *ms, | |
1652 | PostcopyDiscardState *pds, | |
1653 | unsigned long start, | |
1654 | unsigned long length) | |
1655 | { | |
1656 | unsigned long end = start + length; /* one after the end */ | |
1657 | unsigned long current; | |
1658 | unsigned long *unsentmap; | |
1659 | ||
1660 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; | |
1661 | for (current = start; current < end; ) { | |
1662 | unsigned long one = find_next_bit(unsentmap, end, current); | |
1663 | ||
1664 | if (one <= end) { | |
1665 | unsigned long zero = find_next_zero_bit(unsentmap, end, one + 1); | |
1666 | unsigned long discard_length; | |
1667 | ||
1668 | if (zero >= end) { | |
1669 | discard_length = end - one; | |
1670 | } else { | |
1671 | discard_length = zero - one; | |
1672 | } | |
d688c62d DDAG |
1673 | if (discard_length) { |
1674 | postcopy_discard_send_range(ms, pds, one, discard_length); | |
1675 | } | |
e0b266f0 DDAG |
1676 | current = one + discard_length; |
1677 | } else { | |
1678 | current = one; | |
1679 | } | |
1680 | } | |
1681 | ||
1682 | return 0; | |
1683 | } | |
1684 | ||
3d0684b2 JQ |
1685 | /** |
1686 | * postcopy_each_ram_send_discard: discard all RAMBlocks | |
1687 | * | |
1688 | * Returns 0 for success or negative for error | |
1689 | * | |
e0b266f0 DDAG |
1690 | * Utility for the outgoing postcopy code. |
1691 | * Calls postcopy_send_discard_bm_ram for each RAMBlock | |
1692 | * passing it bitmap indexes and name. | |
e0b266f0 DDAG |
1693 | * (qemu_ram_foreach_block ends up passing unscaled lengths |
1694 | * which would mean postcopy code would have to deal with target page) | |
3d0684b2 JQ |
1695 | * |
1696 | * @ms: current migration state | |
e0b266f0 DDAG |
1697 | */ |
1698 | static int postcopy_each_ram_send_discard(MigrationState *ms) | |
1699 | { | |
1700 | struct RAMBlock *block; | |
1701 | int ret; | |
1702 | ||
1703 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
1704 | unsigned long first = block->offset >> TARGET_PAGE_BITS; | |
1705 | PostcopyDiscardState *pds = postcopy_discard_send_init(ms, | |
1706 | first, | |
1707 | block->idstr); | |
1708 | ||
1709 | /* | |
1710 | * Postcopy sends chunks of bitmap over the wire, but it | |
1711 | * just needs indexes at this point, avoids it having | |
1712 | * target page specific code. | |
1713 | */ | |
1714 | ret = postcopy_send_discard_bm_ram(ms, pds, first, | |
1715 | block->used_length >> TARGET_PAGE_BITS); | |
1716 | postcopy_discard_send_finish(ms, pds); | |
1717 | if (ret) { | |
1718 | return ret; | |
1719 | } | |
1720 | } | |
1721 | ||
1722 | return 0; | |
1723 | } | |
1724 | ||
3d0684b2 JQ |
1725 | /** |
1726 | * postcopy_chunk_hostpages_pass: canocalize bitmap in hostpages | |
1727 | * | |
1728 | * Helper for postcopy_chunk_hostpages; it's called twice to | |
1729 | * canonicalize the two bitmaps, that are similar, but one is | |
1730 | * inverted. | |
99e314eb | 1731 | * |
3d0684b2 JQ |
1732 | * Postcopy requires that all target pages in a hostpage are dirty or |
1733 | * clean, not a mix. This function canonicalizes the bitmaps. | |
99e314eb | 1734 | * |
3d0684b2 JQ |
1735 | * @ms: current migration state |
1736 | * @unsent_pass: if true we need to canonicalize partially unsent host pages | |
1737 | * otherwise we need to canonicalize partially dirty host pages | |
1738 | * @block: block that contains the page we want to canonicalize | |
1739 | * @pds: state for postcopy | |
99e314eb DDAG |
1740 | */ |
1741 | static void postcopy_chunk_hostpages_pass(MigrationState *ms, bool unsent_pass, | |
1742 | RAMBlock *block, | |
1743 | PostcopyDiscardState *pds) | |
1744 | { | |
1745 | unsigned long *bitmap; | |
1746 | unsigned long *unsentmap; | |
29c59172 | 1747 | unsigned int host_ratio = block->page_size / TARGET_PAGE_SIZE; |
99e314eb DDAG |
1748 | unsigned long first = block->offset >> TARGET_PAGE_BITS; |
1749 | unsigned long len = block->used_length >> TARGET_PAGE_BITS; | |
1750 | unsigned long last = first + (len - 1); | |
1751 | unsigned long run_start; | |
1752 | ||
29c59172 DDAG |
1753 | if (block->page_size == TARGET_PAGE_SIZE) { |
1754 | /* Easy case - TPS==HPS for a non-huge page RAMBlock */ | |
1755 | return; | |
1756 | } | |
1757 | ||
99e314eb DDAG |
1758 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
1759 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; | |
1760 | ||
1761 | if (unsent_pass) { | |
1762 | /* Find a sent page */ | |
1763 | run_start = find_next_zero_bit(unsentmap, last + 1, first); | |
1764 | } else { | |
1765 | /* Find a dirty page */ | |
1766 | run_start = find_next_bit(bitmap, last + 1, first); | |
1767 | } | |
1768 | ||
1769 | while (run_start <= last) { | |
1770 | bool do_fixup = false; | |
1771 | unsigned long fixup_start_addr; | |
1772 | unsigned long host_offset; | |
1773 | ||
1774 | /* | |
1775 | * If the start of this run of pages is in the middle of a host | |
1776 | * page, then we need to fixup this host page. | |
1777 | */ | |
1778 | host_offset = run_start % host_ratio; | |
1779 | if (host_offset) { | |
1780 | do_fixup = true; | |
1781 | run_start -= host_offset; | |
1782 | fixup_start_addr = run_start; | |
1783 | /* For the next pass */ | |
1784 | run_start = run_start + host_ratio; | |
1785 | } else { | |
1786 | /* Find the end of this run */ | |
1787 | unsigned long run_end; | |
1788 | if (unsent_pass) { | |
1789 | run_end = find_next_bit(unsentmap, last + 1, run_start + 1); | |
1790 | } else { | |
1791 | run_end = find_next_zero_bit(bitmap, last + 1, run_start + 1); | |
1792 | } | |
1793 | /* | |
1794 | * If the end isn't at the start of a host page, then the | |
1795 | * run doesn't finish at the end of a host page | |
1796 | * and we need to discard. | |
1797 | */ | |
1798 | host_offset = run_end % host_ratio; | |
1799 | if (host_offset) { | |
1800 | do_fixup = true; | |
1801 | fixup_start_addr = run_end - host_offset; | |
1802 | /* | |
1803 | * This host page has gone, the next loop iteration starts | |
1804 | * from after the fixup | |
1805 | */ | |
1806 | run_start = fixup_start_addr + host_ratio; | |
1807 | } else { | |
1808 | /* | |
1809 | * No discards on this iteration, next loop starts from | |
1810 | * next sent/dirty page | |
1811 | */ | |
1812 | run_start = run_end + 1; | |
1813 | } | |
1814 | } | |
1815 | ||
1816 | if (do_fixup) { | |
1817 | unsigned long page; | |
1818 | ||
1819 | /* Tell the destination to discard this page */ | |
1820 | if (unsent_pass || !test_bit(fixup_start_addr, unsentmap)) { | |
1821 | /* For the unsent_pass we: | |
1822 | * discard partially sent pages | |
1823 | * For the !unsent_pass (dirty) we: | |
1824 | * discard partially dirty pages that were sent | |
1825 | * (any partially sent pages were already discarded | |
1826 | * by the previous unsent_pass) | |
1827 | */ | |
1828 | postcopy_discard_send_range(ms, pds, fixup_start_addr, | |
1829 | host_ratio); | |
1830 | } | |
1831 | ||
1832 | /* Clean up the bitmap */ | |
1833 | for (page = fixup_start_addr; | |
1834 | page < fixup_start_addr + host_ratio; page++) { | |
1835 | /* All pages in this host page are now not sent */ | |
1836 | set_bit(page, unsentmap); | |
1837 | ||
1838 | /* | |
1839 | * Remark them as dirty, updating the count for any pages | |
1840 | * that weren't previously dirty. | |
1841 | */ | |
1842 | migration_dirty_pages += !test_and_set_bit(page, bitmap); | |
1843 | } | |
1844 | } | |
1845 | ||
1846 | if (unsent_pass) { | |
1847 | /* Find the next sent page for the next iteration */ | |
1848 | run_start = find_next_zero_bit(unsentmap, last + 1, | |
1849 | run_start); | |
1850 | } else { | |
1851 | /* Find the next dirty page for the next iteration */ | |
1852 | run_start = find_next_bit(bitmap, last + 1, run_start); | |
1853 | } | |
1854 | } | |
1855 | } | |
1856 | ||
3d0684b2 JQ |
1857 | /** |
1858 | * postcopy_chuck_hostpages: discrad any partially sent host page | |
1859 | * | |
99e314eb DDAG |
1860 | * Utility for the outgoing postcopy code. |
1861 | * | |
1862 | * Discard any partially sent host-page size chunks, mark any partially | |
29c59172 DDAG |
1863 | * dirty host-page size chunks as all dirty. In this case the host-page |
1864 | * is the host-page for the particular RAMBlock, i.e. it might be a huge page | |
99e314eb | 1865 | * |
3d0684b2 JQ |
1866 | * Returns zero on success |
1867 | * | |
1868 | * @ms: current migration state | |
99e314eb DDAG |
1869 | */ |
1870 | static int postcopy_chunk_hostpages(MigrationState *ms) | |
1871 | { | |
6f37bb8b | 1872 | RAMState *rs = &ram_state; |
99e314eb DDAG |
1873 | struct RAMBlock *block; |
1874 | ||
99e314eb | 1875 | /* Easiest way to make sure we don't resume in the middle of a host-page */ |
6f37bb8b JQ |
1876 | rs->last_seen_block = NULL; |
1877 | rs->last_sent_block = NULL; | |
1878 | rs->last_offset = 0; | |
99e314eb DDAG |
1879 | |
1880 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
1881 | unsigned long first = block->offset >> TARGET_PAGE_BITS; | |
1882 | ||
1883 | PostcopyDiscardState *pds = | |
1884 | postcopy_discard_send_init(ms, first, block->idstr); | |
1885 | ||
1886 | /* First pass: Discard all partially sent host pages */ | |
1887 | postcopy_chunk_hostpages_pass(ms, true, block, pds); | |
1888 | /* | |
1889 | * Second pass: Ensure that all partially dirty host pages are made | |
1890 | * fully dirty. | |
1891 | */ | |
1892 | postcopy_chunk_hostpages_pass(ms, false, block, pds); | |
1893 | ||
1894 | postcopy_discard_send_finish(ms, pds); | |
1895 | } /* ram_list loop */ | |
1896 | ||
1897 | return 0; | |
1898 | } | |
1899 | ||
3d0684b2 JQ |
1900 | /** |
1901 | * ram_postcopy_send_discard_bitmap: transmit the discard bitmap | |
1902 | * | |
1903 | * Returns zero on success | |
1904 | * | |
e0b266f0 DDAG |
1905 | * Transmit the set of pages to be discarded after precopy to the target |
1906 | * these are pages that: | |
1907 | * a) Have been previously transmitted but are now dirty again | |
1908 | * b) Pages that have never been transmitted, this ensures that | |
1909 | * any pages on the destination that have been mapped by background | |
1910 | * tasks get discarded (transparent huge pages is the specific concern) | |
1911 | * Hopefully this is pretty sparse | |
3d0684b2 JQ |
1912 | * |
1913 | * @ms: current migration state | |
e0b266f0 DDAG |
1914 | */ |
1915 | int ram_postcopy_send_discard_bitmap(MigrationState *ms) | |
1916 | { | |
1917 | int ret; | |
1918 | unsigned long *bitmap, *unsentmap; | |
1919 | ||
1920 | rcu_read_lock(); | |
1921 | ||
1922 | /* This should be our last sync, the src is now paused */ | |
1923 | migration_bitmap_sync(); | |
1924 | ||
1925 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; | |
1926 | if (!unsentmap) { | |
1927 | /* We don't have a safe way to resize the sentmap, so | |
1928 | * if the bitmap was resized it will be NULL at this | |
1929 | * point. | |
1930 | */ | |
1931 | error_report("migration ram resized during precopy phase"); | |
1932 | rcu_read_unlock(); | |
1933 | return -EINVAL; | |
1934 | } | |
1935 | ||
29c59172 | 1936 | /* Deal with TPS != HPS and huge pages */ |
99e314eb DDAG |
1937 | ret = postcopy_chunk_hostpages(ms); |
1938 | if (ret) { | |
1939 | rcu_read_unlock(); | |
1940 | return ret; | |
1941 | } | |
1942 | ||
e0b266f0 DDAG |
1943 | /* |
1944 | * Update the unsentmap to be unsentmap = unsentmap | dirty | |
1945 | */ | |
1946 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; | |
1947 | bitmap_or(unsentmap, unsentmap, bitmap, | |
1948 | last_ram_offset() >> TARGET_PAGE_BITS); | |
1949 | ||
1950 | ||
1951 | trace_ram_postcopy_send_discard_bitmap(); | |
1952 | #ifdef DEBUG_POSTCOPY | |
1953 | ram_debug_dump_bitmap(unsentmap, true); | |
1954 | #endif | |
1955 | ||
1956 | ret = postcopy_each_ram_send_discard(ms); | |
1957 | rcu_read_unlock(); | |
1958 | ||
1959 | return ret; | |
1960 | } | |
1961 | ||
3d0684b2 JQ |
1962 | /** |
1963 | * ram_discard_range: discard dirtied pages at the beginning of postcopy | |
e0b266f0 | 1964 | * |
3d0684b2 | 1965 | * Returns zero on success |
e0b266f0 | 1966 | * |
3d0684b2 | 1967 | * @mis: current migration incoming state |
36449157 JQ |
1968 | * @rbname: name of the RAMBlock of the request. NULL means the |
1969 | * same that last one. | |
3d0684b2 JQ |
1970 | * @start: RAMBlock starting page |
1971 | * @length: RAMBlock size | |
e0b266f0 DDAG |
1972 | */ |
1973 | int ram_discard_range(MigrationIncomingState *mis, | |
36449157 | 1974 | const char *rbname, |
e0b266f0 DDAG |
1975 | uint64_t start, size_t length) |
1976 | { | |
1977 | int ret = -1; | |
1978 | ||
36449157 | 1979 | trace_ram_discard_range(rbname, start, length); |
d3a5038c | 1980 | |
e0b266f0 | 1981 | rcu_read_lock(); |
36449157 | 1982 | RAMBlock *rb = qemu_ram_block_by_name(rbname); |
e0b266f0 DDAG |
1983 | |
1984 | if (!rb) { | |
36449157 | 1985 | error_report("ram_discard_range: Failed to find block '%s'", rbname); |
e0b266f0 DDAG |
1986 | goto err; |
1987 | } | |
1988 | ||
d3a5038c | 1989 | ret = ram_block_discard_range(rb, start, length); |
e0b266f0 DDAG |
1990 | |
1991 | err: | |
1992 | rcu_read_unlock(); | |
1993 | ||
1994 | return ret; | |
1995 | } | |
1996 | ||
6f37bb8b | 1997 | static int ram_save_init_globals(RAMState *rs) |
56e93d26 | 1998 | { |
56e93d26 JQ |
1999 | int64_t ram_bitmap_pages; /* Size of bitmap in pages, including gaps */ |
2000 | ||
56e93d26 JQ |
2001 | dirty_rate_high_cnt = 0; |
2002 | bitmap_sync_count = 0; | |
2003 | migration_bitmap_sync_init(); | |
dd631697 | 2004 | qemu_mutex_init(&migration_bitmap_mutex); |
56e93d26 JQ |
2005 | |
2006 | if (migrate_use_xbzrle()) { | |
2007 | XBZRLE_cache_lock(); | |
adb65dec | 2008 | ZERO_TARGET_PAGE = g_malloc0(TARGET_PAGE_SIZE); |
56e93d26 JQ |
2009 | XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / |
2010 | TARGET_PAGE_SIZE, | |
2011 | TARGET_PAGE_SIZE); | |
2012 | if (!XBZRLE.cache) { | |
2013 | XBZRLE_cache_unlock(); | |
2014 | error_report("Error creating cache"); | |
2015 | return -1; | |
2016 | } | |
2017 | XBZRLE_cache_unlock(); | |
2018 | ||
2019 | /* We prefer not to abort if there is no memory */ | |
2020 | XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); | |
2021 | if (!XBZRLE.encoded_buf) { | |
2022 | error_report("Error allocating encoded_buf"); | |
2023 | return -1; | |
2024 | } | |
2025 | ||
2026 | XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); | |
2027 | if (!XBZRLE.current_buf) { | |
2028 | error_report("Error allocating current_buf"); | |
2029 | g_free(XBZRLE.encoded_buf); | |
2030 | XBZRLE.encoded_buf = NULL; | |
2031 | return -1; | |
2032 | } | |
2033 | ||
2034 | acct_clear(); | |
2035 | } | |
2036 | ||
49877834 PB |
2037 | /* For memory_global_dirty_log_start below. */ |
2038 | qemu_mutex_lock_iothread(); | |
2039 | ||
56e93d26 JQ |
2040 | qemu_mutex_lock_ramlist(); |
2041 | rcu_read_lock(); | |
2042 | bytes_transferred = 0; | |
6f37bb8b | 2043 | ram_state_reset(rs); |
56e93d26 | 2044 | |
f3f491fc | 2045 | migration_bitmap_rcu = g_new0(struct BitmapRcu, 1); |
0827b9e9 AA |
2046 | /* Skip setting bitmap if there is no RAM */ |
2047 | if (ram_bytes_total()) { | |
2048 | ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS; | |
2049 | migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages); | |
2050 | bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages); | |
2051 | ||
2052 | if (migrate_postcopy_ram()) { | |
2053 | migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages); | |
2054 | bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages); | |
2055 | } | |
f3f491fc DDAG |
2056 | } |
2057 | ||
56e93d26 JQ |
2058 | /* |
2059 | * Count the total number of pages used by ram blocks not including any | |
2060 | * gaps due to alignment or unplugs. | |
2061 | */ | |
2062 | migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS; | |
2063 | ||
2064 | memory_global_dirty_log_start(); | |
2065 | migration_bitmap_sync(); | |
2066 | qemu_mutex_unlock_ramlist(); | |
49877834 | 2067 | qemu_mutex_unlock_iothread(); |
a91246c9 HZ |
2068 | rcu_read_unlock(); |
2069 | ||
2070 | return 0; | |
2071 | } | |
2072 | ||
3d0684b2 JQ |
2073 | /* |
2074 | * Each of ram_save_setup, ram_save_iterate and ram_save_complete has | |
a91246c9 HZ |
2075 | * long-running RCU critical section. When rcu-reclaims in the code |
2076 | * start to become numerous it will be necessary to reduce the | |
2077 | * granularity of these critical sections. | |
2078 | */ | |
2079 | ||
3d0684b2 JQ |
2080 | /** |
2081 | * ram_save_setup: Setup RAM for migration | |
2082 | * | |
2083 | * Returns zero to indicate success and negative for error | |
2084 | * | |
2085 | * @f: QEMUFile where to send the data | |
2086 | * @opaque: RAMState pointer | |
2087 | */ | |
a91246c9 HZ |
2088 | static int ram_save_setup(QEMUFile *f, void *opaque) |
2089 | { | |
6f37bb8b | 2090 | RAMState *rs = opaque; |
a91246c9 HZ |
2091 | RAMBlock *block; |
2092 | ||
2093 | /* migration has already setup the bitmap, reuse it. */ | |
2094 | if (!migration_in_colo_state()) { | |
6f37bb8b | 2095 | if (ram_save_init_globals(rs) < 0) { |
a91246c9 HZ |
2096 | return -1; |
2097 | } | |
2098 | } | |
2099 | ||
2100 | rcu_read_lock(); | |
56e93d26 JQ |
2101 | |
2102 | qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE); | |
2103 | ||
2104 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { | |
2105 | qemu_put_byte(f, strlen(block->idstr)); | |
2106 | qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); | |
2107 | qemu_put_be64(f, block->used_length); | |
ef08fb38 DDAG |
2108 | if (migrate_postcopy_ram() && block->page_size != qemu_host_page_size) { |
2109 | qemu_put_be64(f, block->page_size); | |
2110 | } | |
56e93d26 JQ |
2111 | } |
2112 | ||
2113 | rcu_read_unlock(); | |
2114 | ||
2115 | ram_control_before_iterate(f, RAM_CONTROL_SETUP); | |
2116 | ram_control_after_iterate(f, RAM_CONTROL_SETUP); | |
2117 | ||
2118 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); | |
2119 | ||
2120 | return 0; | |
2121 | } | |
2122 | ||
3d0684b2 JQ |
2123 | /** |
2124 | * ram_save_iterate: iterative stage for migration | |
2125 | * | |
2126 | * Returns zero to indicate success and negative for error | |
2127 | * | |
2128 | * @f: QEMUFile where to send the data | |
2129 | * @opaque: RAMState pointer | |
2130 | */ | |
56e93d26 JQ |
2131 | static int ram_save_iterate(QEMUFile *f, void *opaque) |
2132 | { | |
6f37bb8b | 2133 | RAMState *rs = opaque; |
56e93d26 JQ |
2134 | int ret; |
2135 | int i; | |
2136 | int64_t t0; | |
5c90308f | 2137 | int done = 0; |
56e93d26 JQ |
2138 | |
2139 | rcu_read_lock(); | |
6f37bb8b JQ |
2140 | if (ram_list.version != rs->last_version) { |
2141 | ram_state_reset(rs); | |
56e93d26 JQ |
2142 | } |
2143 | ||
2144 | /* Read version before ram_list.blocks */ | |
2145 | smp_rmb(); | |
2146 | ||
2147 | ram_control_before_iterate(f, RAM_CONTROL_ROUND); | |
2148 | ||
2149 | t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); | |
2150 | i = 0; | |
2151 | while ((ret = qemu_file_rate_limit(f)) == 0) { | |
2152 | int pages; | |
2153 | ||
6f37bb8b | 2154 | pages = ram_find_and_save_block(rs, f, false, &bytes_transferred); |
56e93d26 JQ |
2155 | /* no more pages to sent */ |
2156 | if (pages == 0) { | |
5c90308f | 2157 | done = 1; |
56e93d26 JQ |
2158 | break; |
2159 | } | |
56e93d26 | 2160 | acct_info.iterations++; |
070afca2 | 2161 | |
56e93d26 JQ |
2162 | /* we want to check in the 1st loop, just in case it was the 1st time |
2163 | and we had to sync the dirty bitmap. | |
2164 | qemu_get_clock_ns() is a bit expensive, so we only check each some | |
2165 | iterations | |
2166 | */ | |
2167 | if ((i & 63) == 0) { | |
2168 | uint64_t t1 = (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - t0) / 1000000; | |
2169 | if (t1 > MAX_WAIT) { | |
55c4446b | 2170 | trace_ram_save_iterate_big_wait(t1, i); |
56e93d26 JQ |
2171 | break; |
2172 | } | |
2173 | } | |
2174 | i++; | |
2175 | } | |
2176 | flush_compressed_data(f); | |
2177 | rcu_read_unlock(); | |
2178 | ||
2179 | /* | |
2180 | * Must occur before EOS (or any QEMUFile operation) | |
2181 | * because of RDMA protocol. | |
2182 | */ | |
2183 | ram_control_after_iterate(f, RAM_CONTROL_ROUND); | |
2184 | ||
2185 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); | |
2186 | bytes_transferred += 8; | |
2187 | ||
2188 | ret = qemu_file_get_error(f); | |
2189 | if (ret < 0) { | |
2190 | return ret; | |
2191 | } | |
2192 | ||
5c90308f | 2193 | return done; |
56e93d26 JQ |
2194 | } |
2195 | ||
3d0684b2 JQ |
2196 | /** |
2197 | * ram_save_complete: function called to send the remaining amount of ram | |
2198 | * | |
2199 | * Returns zero to indicate success | |
2200 | * | |
2201 | * Called with iothread lock | |
2202 | * | |
2203 | * @f: QEMUFile where to send the data | |
2204 | * @opaque: RAMState pointer | |
2205 | */ | |
56e93d26 JQ |
2206 | static int ram_save_complete(QEMUFile *f, void *opaque) |
2207 | { | |
6f37bb8b JQ |
2208 | RAMState *rs = opaque; |
2209 | ||
56e93d26 JQ |
2210 | rcu_read_lock(); |
2211 | ||
663e6c1d DDAG |
2212 | if (!migration_in_postcopy(migrate_get_current())) { |
2213 | migration_bitmap_sync(); | |
2214 | } | |
56e93d26 JQ |
2215 | |
2216 | ram_control_before_iterate(f, RAM_CONTROL_FINISH); | |
2217 | ||
2218 | /* try transferring iterative blocks of memory */ | |
2219 | ||
2220 | /* flush all remaining blocks regardless of rate limiting */ | |
2221 | while (true) { | |
2222 | int pages; | |
2223 | ||
6f37bb8b | 2224 | pages = ram_find_and_save_block(rs, f, !migration_in_colo_state(), |
a91246c9 | 2225 | &bytes_transferred); |
56e93d26 JQ |
2226 | /* no more blocks to sent */ |
2227 | if (pages == 0) { | |
2228 | break; | |
2229 | } | |
2230 | } | |
2231 | ||
2232 | flush_compressed_data(f); | |
2233 | ram_control_after_iterate(f, RAM_CONTROL_FINISH); | |
56e93d26 JQ |
2234 | |
2235 | rcu_read_unlock(); | |
d09a6fde | 2236 | |
56e93d26 JQ |
2237 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
2238 | ||
2239 | return 0; | |
2240 | } | |
2241 | ||
c31b098f DDAG |
2242 | static void ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size, |
2243 | uint64_t *non_postcopiable_pending, | |
2244 | uint64_t *postcopiable_pending) | |
56e93d26 JQ |
2245 | { |
2246 | uint64_t remaining_size; | |
2247 | ||
2248 | remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; | |
2249 | ||
663e6c1d DDAG |
2250 | if (!migration_in_postcopy(migrate_get_current()) && |
2251 | remaining_size < max_size) { | |
56e93d26 JQ |
2252 | qemu_mutex_lock_iothread(); |
2253 | rcu_read_lock(); | |
2254 | migration_bitmap_sync(); | |
2255 | rcu_read_unlock(); | |
2256 | qemu_mutex_unlock_iothread(); | |
2257 | remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; | |
2258 | } | |
c31b098f DDAG |
2259 | |
2260 | /* We can do postcopy, and all the data is postcopiable */ | |
2261 | *postcopiable_pending += remaining_size; | |
56e93d26 JQ |
2262 | } |
2263 | ||
2264 | static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) | |
2265 | { | |
2266 | unsigned int xh_len; | |
2267 | int xh_flags; | |
063e760a | 2268 | uint8_t *loaded_data; |
56e93d26 JQ |
2269 | |
2270 | if (!xbzrle_decoded_buf) { | |
2271 | xbzrle_decoded_buf = g_malloc(TARGET_PAGE_SIZE); | |
2272 | } | |
063e760a | 2273 | loaded_data = xbzrle_decoded_buf; |
56e93d26 JQ |
2274 | |
2275 | /* extract RLE header */ | |
2276 | xh_flags = qemu_get_byte(f); | |
2277 | xh_len = qemu_get_be16(f); | |
2278 | ||
2279 | if (xh_flags != ENCODING_FLAG_XBZRLE) { | |
2280 | error_report("Failed to load XBZRLE page - wrong compression!"); | |
2281 | return -1; | |
2282 | } | |
2283 | ||
2284 | if (xh_len > TARGET_PAGE_SIZE) { | |
2285 | error_report("Failed to load XBZRLE page - len overflow!"); | |
2286 | return -1; | |
2287 | } | |
2288 | /* load data and decode */ | |
063e760a | 2289 | qemu_get_buffer_in_place(f, &loaded_data, xh_len); |
56e93d26 JQ |
2290 | |
2291 | /* decode RLE */ | |
063e760a | 2292 | if (xbzrle_decode_buffer(loaded_data, xh_len, host, |
56e93d26 JQ |
2293 | TARGET_PAGE_SIZE) == -1) { |
2294 | error_report("Failed to load XBZRLE page - decode error!"); | |
2295 | return -1; | |
2296 | } | |
2297 | ||
2298 | return 0; | |
2299 | } | |
2300 | ||
3d0684b2 JQ |
2301 | /** |
2302 | * ram_block_from_stream: read a RAMBlock id from the migration stream | |
2303 | * | |
2304 | * Must be called from within a rcu critical section. | |
2305 | * | |
56e93d26 | 2306 | * Returns a pointer from within the RCU-protected ram_list. |
a7180877 | 2307 | * |
3d0684b2 JQ |
2308 | * @f: QEMUFile where to read the data from |
2309 | * @flags: Page flags (mostly to see if it's a continuation of previous block) | |
a7180877 | 2310 | */ |
3d0684b2 | 2311 | static inline RAMBlock *ram_block_from_stream(QEMUFile *f, int flags) |
56e93d26 JQ |
2312 | { |
2313 | static RAMBlock *block = NULL; | |
2314 | char id[256]; | |
2315 | uint8_t len; | |
2316 | ||
2317 | if (flags & RAM_SAVE_FLAG_CONTINUE) { | |
4c4bad48 | 2318 | if (!block) { |
56e93d26 JQ |
2319 | error_report("Ack, bad migration stream!"); |
2320 | return NULL; | |
2321 | } | |
4c4bad48 | 2322 | return block; |
56e93d26 JQ |
2323 | } |
2324 | ||
2325 | len = qemu_get_byte(f); | |
2326 | qemu_get_buffer(f, (uint8_t *)id, len); | |
2327 | id[len] = 0; | |
2328 | ||
e3dd7493 | 2329 | block = qemu_ram_block_by_name(id); |
4c4bad48 HZ |
2330 | if (!block) { |
2331 | error_report("Can't find block %s", id); | |
2332 | return NULL; | |
56e93d26 JQ |
2333 | } |
2334 | ||
4c4bad48 HZ |
2335 | return block; |
2336 | } | |
2337 | ||
2338 | static inline void *host_from_ram_block_offset(RAMBlock *block, | |
2339 | ram_addr_t offset) | |
2340 | { | |
2341 | if (!offset_in_ramblock(block, offset)) { | |
2342 | return NULL; | |
2343 | } | |
2344 | ||
2345 | return block->host + offset; | |
56e93d26 JQ |
2346 | } |
2347 | ||
3d0684b2 JQ |
2348 | /** |
2349 | * ram_handle_compressed: handle the zero page case | |
2350 | * | |
56e93d26 JQ |
2351 | * If a page (or a whole RDMA chunk) has been |
2352 | * determined to be zero, then zap it. | |
3d0684b2 JQ |
2353 | * |
2354 | * @host: host address for the zero page | |
2355 | * @ch: what the page is filled from. We only support zero | |
2356 | * @size: size of the zero page | |
56e93d26 JQ |
2357 | */ |
2358 | void ram_handle_compressed(void *host, uint8_t ch, uint64_t size) | |
2359 | { | |
2360 | if (ch != 0 || !is_zero_range(host, size)) { | |
2361 | memset(host, ch, size); | |
2362 | } | |
2363 | } | |
2364 | ||
2365 | static void *do_data_decompress(void *opaque) | |
2366 | { | |
2367 | DecompressParam *param = opaque; | |
2368 | unsigned long pagesize; | |
33d151f4 LL |
2369 | uint8_t *des; |
2370 | int len; | |
56e93d26 | 2371 | |
33d151f4 | 2372 | qemu_mutex_lock(¶m->mutex); |
90e56fb4 | 2373 | while (!param->quit) { |
33d151f4 LL |
2374 | if (param->des) { |
2375 | des = param->des; | |
2376 | len = param->len; | |
2377 | param->des = 0; | |
2378 | qemu_mutex_unlock(¶m->mutex); | |
2379 | ||
56e93d26 | 2380 | pagesize = TARGET_PAGE_SIZE; |
73a8912b LL |
2381 | /* uncompress() will return failed in some case, especially |
2382 | * when the page is dirted when doing the compression, it's | |
2383 | * not a problem because the dirty page will be retransferred | |
2384 | * and uncompress() won't break the data in other pages. | |
2385 | */ | |
33d151f4 LL |
2386 | uncompress((Bytef *)des, &pagesize, |
2387 | (const Bytef *)param->compbuf, len); | |
73a8912b | 2388 | |
33d151f4 LL |
2389 | qemu_mutex_lock(&decomp_done_lock); |
2390 | param->done = true; | |
2391 | qemu_cond_signal(&decomp_done_cond); | |
2392 | qemu_mutex_unlock(&decomp_done_lock); | |
2393 | ||
2394 | qemu_mutex_lock(¶m->mutex); | |
2395 | } else { | |
2396 | qemu_cond_wait(¶m->cond, ¶m->mutex); | |
2397 | } | |
56e93d26 | 2398 | } |
33d151f4 | 2399 | qemu_mutex_unlock(¶m->mutex); |
56e93d26 JQ |
2400 | |
2401 | return NULL; | |
2402 | } | |
2403 | ||
5533b2e9 LL |
2404 | static void wait_for_decompress_done(void) |
2405 | { | |
2406 | int idx, thread_count; | |
2407 | ||
2408 | if (!migrate_use_compression()) { | |
2409 | return; | |
2410 | } | |
2411 | ||
2412 | thread_count = migrate_decompress_threads(); | |
2413 | qemu_mutex_lock(&decomp_done_lock); | |
2414 | for (idx = 0; idx < thread_count; idx++) { | |
2415 | while (!decomp_param[idx].done) { | |
2416 | qemu_cond_wait(&decomp_done_cond, &decomp_done_lock); | |
2417 | } | |
2418 | } | |
2419 | qemu_mutex_unlock(&decomp_done_lock); | |
2420 | } | |
2421 | ||
56e93d26 JQ |
2422 | void migrate_decompress_threads_create(void) |
2423 | { | |
2424 | int i, thread_count; | |
2425 | ||
2426 | thread_count = migrate_decompress_threads(); | |
2427 | decompress_threads = g_new0(QemuThread, thread_count); | |
2428 | decomp_param = g_new0(DecompressParam, thread_count); | |
73a8912b LL |
2429 | qemu_mutex_init(&decomp_done_lock); |
2430 | qemu_cond_init(&decomp_done_cond); | |
56e93d26 JQ |
2431 | for (i = 0; i < thread_count; i++) { |
2432 | qemu_mutex_init(&decomp_param[i].mutex); | |
2433 | qemu_cond_init(&decomp_param[i].cond); | |
2434 | decomp_param[i].compbuf = g_malloc0(compressBound(TARGET_PAGE_SIZE)); | |
73a8912b | 2435 | decomp_param[i].done = true; |
90e56fb4 | 2436 | decomp_param[i].quit = false; |
56e93d26 JQ |
2437 | qemu_thread_create(decompress_threads + i, "decompress", |
2438 | do_data_decompress, decomp_param + i, | |
2439 | QEMU_THREAD_JOINABLE); | |
2440 | } | |
2441 | } | |
2442 | ||
2443 | void migrate_decompress_threads_join(void) | |
2444 | { | |
2445 | int i, thread_count; | |
2446 | ||
56e93d26 JQ |
2447 | thread_count = migrate_decompress_threads(); |
2448 | for (i = 0; i < thread_count; i++) { | |
2449 | qemu_mutex_lock(&decomp_param[i].mutex); | |
90e56fb4 | 2450 | decomp_param[i].quit = true; |
56e93d26 JQ |
2451 | qemu_cond_signal(&decomp_param[i].cond); |
2452 | qemu_mutex_unlock(&decomp_param[i].mutex); | |
2453 | } | |
2454 | for (i = 0; i < thread_count; i++) { | |
2455 | qemu_thread_join(decompress_threads + i); | |
2456 | qemu_mutex_destroy(&decomp_param[i].mutex); | |
2457 | qemu_cond_destroy(&decomp_param[i].cond); | |
2458 | g_free(decomp_param[i].compbuf); | |
2459 | } | |
2460 | g_free(decompress_threads); | |
2461 | g_free(decomp_param); | |
56e93d26 JQ |
2462 | decompress_threads = NULL; |
2463 | decomp_param = NULL; | |
56e93d26 JQ |
2464 | } |
2465 | ||
c1bc6626 | 2466 | static void decompress_data_with_multi_threads(QEMUFile *f, |
56e93d26 JQ |
2467 | void *host, int len) |
2468 | { | |
2469 | int idx, thread_count; | |
2470 | ||
2471 | thread_count = migrate_decompress_threads(); | |
73a8912b | 2472 | qemu_mutex_lock(&decomp_done_lock); |
56e93d26 JQ |
2473 | while (true) { |
2474 | for (idx = 0; idx < thread_count; idx++) { | |
73a8912b | 2475 | if (decomp_param[idx].done) { |
33d151f4 LL |
2476 | decomp_param[idx].done = false; |
2477 | qemu_mutex_lock(&decomp_param[idx].mutex); | |
c1bc6626 | 2478 | qemu_get_buffer(f, decomp_param[idx].compbuf, len); |
56e93d26 JQ |
2479 | decomp_param[idx].des = host; |
2480 | decomp_param[idx].len = len; | |
33d151f4 LL |
2481 | qemu_cond_signal(&decomp_param[idx].cond); |
2482 | qemu_mutex_unlock(&decomp_param[idx].mutex); | |
56e93d26 JQ |
2483 | break; |
2484 | } | |
2485 | } | |
2486 | if (idx < thread_count) { | |
2487 | break; | |
73a8912b LL |
2488 | } else { |
2489 | qemu_cond_wait(&decomp_done_cond, &decomp_done_lock); | |
56e93d26 JQ |
2490 | } |
2491 | } | |
73a8912b | 2492 | qemu_mutex_unlock(&decomp_done_lock); |
56e93d26 JQ |
2493 | } |
2494 | ||
3d0684b2 JQ |
2495 | /** |
2496 | * ram_postcopy_incoming_init: allocate postcopy data structures | |
2497 | * | |
2498 | * Returns 0 for success and negative if there was one error | |
2499 | * | |
2500 | * @mis: current migration incoming state | |
2501 | * | |
2502 | * Allocate data structures etc needed by incoming migration with | |
2503 | * postcopy-ram. postcopy-ram's similarly names | |
2504 | * postcopy_ram_incoming_init does the work. | |
1caddf8a DDAG |
2505 | */ |
2506 | int ram_postcopy_incoming_init(MigrationIncomingState *mis) | |
2507 | { | |
2508 | size_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; | |
2509 | ||
2510 | return postcopy_ram_incoming_init(mis, ram_pages); | |
2511 | } | |
2512 | ||
3d0684b2 JQ |
2513 | /** |
2514 | * ram_load_postcopy: load a page in postcopy case | |
2515 | * | |
2516 | * Returns 0 for success or -errno in case of error | |
2517 | * | |
a7180877 DDAG |
2518 | * Called in postcopy mode by ram_load(). |
2519 | * rcu_read_lock is taken prior to this being called. | |
3d0684b2 JQ |
2520 | * |
2521 | * @f: QEMUFile where to send the data | |
a7180877 DDAG |
2522 | */ |
2523 | static int ram_load_postcopy(QEMUFile *f) | |
2524 | { | |
2525 | int flags = 0, ret = 0; | |
2526 | bool place_needed = false; | |
28abd200 | 2527 | bool matching_page_sizes = false; |
a7180877 DDAG |
2528 | MigrationIncomingState *mis = migration_incoming_get_current(); |
2529 | /* Temporary page that is later 'placed' */ | |
2530 | void *postcopy_host_page = postcopy_get_tmp_page(mis); | |
c53b7ddc | 2531 | void *last_host = NULL; |
a3b6ff6d | 2532 | bool all_zero = false; |
a7180877 DDAG |
2533 | |
2534 | while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { | |
2535 | ram_addr_t addr; | |
2536 | void *host = NULL; | |
2537 | void *page_buffer = NULL; | |
2538 | void *place_source = NULL; | |
df9ff5e1 | 2539 | RAMBlock *block = NULL; |
a7180877 | 2540 | uint8_t ch; |
a7180877 DDAG |
2541 | |
2542 | addr = qemu_get_be64(f); | |
2543 | flags = addr & ~TARGET_PAGE_MASK; | |
2544 | addr &= TARGET_PAGE_MASK; | |
2545 | ||
2546 | trace_ram_load_postcopy_loop((uint64_t)addr, flags); | |
2547 | place_needed = false; | |
2548 | if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE)) { | |
df9ff5e1 | 2549 | block = ram_block_from_stream(f, flags); |
4c4bad48 HZ |
2550 | |
2551 | host = host_from_ram_block_offset(block, addr); | |
a7180877 DDAG |
2552 | if (!host) { |
2553 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); | |
2554 | ret = -EINVAL; | |
2555 | break; | |
2556 | } | |
28abd200 | 2557 | matching_page_sizes = block->page_size == TARGET_PAGE_SIZE; |
a7180877 | 2558 | /* |
28abd200 DDAG |
2559 | * Postcopy requires that we place whole host pages atomically; |
2560 | * these may be huge pages for RAMBlocks that are backed by | |
2561 | * hugetlbfs. | |
a7180877 DDAG |
2562 | * To make it atomic, the data is read into a temporary page |
2563 | * that's moved into place later. | |
2564 | * The migration protocol uses, possibly smaller, target-pages | |
2565 | * however the source ensures it always sends all the components | |
2566 | * of a host page in order. | |
2567 | */ | |
2568 | page_buffer = postcopy_host_page + | |
28abd200 | 2569 | ((uintptr_t)host & (block->page_size - 1)); |
a7180877 | 2570 | /* If all TP are zero then we can optimise the place */ |
28abd200 | 2571 | if (!((uintptr_t)host & (block->page_size - 1))) { |
a7180877 | 2572 | all_zero = true; |
c53b7ddc DDAG |
2573 | } else { |
2574 | /* not the 1st TP within the HP */ | |
2575 | if (host != (last_host + TARGET_PAGE_SIZE)) { | |
9af9e0fe | 2576 | error_report("Non-sequential target page %p/%p", |
c53b7ddc DDAG |
2577 | host, last_host); |
2578 | ret = -EINVAL; | |
2579 | break; | |
2580 | } | |
a7180877 DDAG |
2581 | } |
2582 | ||
c53b7ddc | 2583 | |
a7180877 DDAG |
2584 | /* |
2585 | * If it's the last part of a host page then we place the host | |
2586 | * page | |
2587 | */ | |
2588 | place_needed = (((uintptr_t)host + TARGET_PAGE_SIZE) & | |
28abd200 | 2589 | (block->page_size - 1)) == 0; |
a7180877 DDAG |
2590 | place_source = postcopy_host_page; |
2591 | } | |
c53b7ddc | 2592 | last_host = host; |
a7180877 DDAG |
2593 | |
2594 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { | |
2595 | case RAM_SAVE_FLAG_COMPRESS: | |
2596 | ch = qemu_get_byte(f); | |
2597 | memset(page_buffer, ch, TARGET_PAGE_SIZE); | |
2598 | if (ch) { | |
2599 | all_zero = false; | |
2600 | } | |
2601 | break; | |
2602 | ||
2603 | case RAM_SAVE_FLAG_PAGE: | |
2604 | all_zero = false; | |
2605 | if (!place_needed || !matching_page_sizes) { | |
2606 | qemu_get_buffer(f, page_buffer, TARGET_PAGE_SIZE); | |
2607 | } else { | |
2608 | /* Avoids the qemu_file copy during postcopy, which is | |
2609 | * going to do a copy later; can only do it when we | |
2610 | * do this read in one go (matching page sizes) | |
2611 | */ | |
2612 | qemu_get_buffer_in_place(f, (uint8_t **)&place_source, | |
2613 | TARGET_PAGE_SIZE); | |
2614 | } | |
2615 | break; | |
2616 | case RAM_SAVE_FLAG_EOS: | |
2617 | /* normal exit */ | |
2618 | break; | |
2619 | default: | |
2620 | error_report("Unknown combination of migration flags: %#x" | |
2621 | " (postcopy mode)", flags); | |
2622 | ret = -EINVAL; | |
2623 | } | |
2624 | ||
2625 | if (place_needed) { | |
2626 | /* This gets called at the last target page in the host page */ | |
df9ff5e1 DDAG |
2627 | void *place_dest = host + TARGET_PAGE_SIZE - block->page_size; |
2628 | ||
a7180877 | 2629 | if (all_zero) { |
df9ff5e1 DDAG |
2630 | ret = postcopy_place_page_zero(mis, place_dest, |
2631 | block->page_size); | |
a7180877 | 2632 | } else { |
df9ff5e1 DDAG |
2633 | ret = postcopy_place_page(mis, place_dest, |
2634 | place_source, block->page_size); | |
a7180877 DDAG |
2635 | } |
2636 | } | |
2637 | if (!ret) { | |
2638 | ret = qemu_file_get_error(f); | |
2639 | } | |
2640 | } | |
2641 | ||
2642 | return ret; | |
2643 | } | |
2644 | ||
56e93d26 JQ |
2645 | static int ram_load(QEMUFile *f, void *opaque, int version_id) |
2646 | { | |
2647 | int flags = 0, ret = 0; | |
2648 | static uint64_t seq_iter; | |
2649 | int len = 0; | |
a7180877 DDAG |
2650 | /* |
2651 | * If system is running in postcopy mode, page inserts to host memory must | |
2652 | * be atomic | |
2653 | */ | |
2654 | bool postcopy_running = postcopy_state_get() >= POSTCOPY_INCOMING_LISTENING; | |
ef08fb38 DDAG |
2655 | /* ADVISE is earlier, it shows the source has the postcopy capability on */ |
2656 | bool postcopy_advised = postcopy_state_get() >= POSTCOPY_INCOMING_ADVISE; | |
56e93d26 JQ |
2657 | |
2658 | seq_iter++; | |
2659 | ||
2660 | if (version_id != 4) { | |
2661 | ret = -EINVAL; | |
2662 | } | |
2663 | ||
2664 | /* This RCU critical section can be very long running. | |
2665 | * When RCU reclaims in the code start to become numerous, | |
2666 | * it will be necessary to reduce the granularity of this | |
2667 | * critical section. | |
2668 | */ | |
2669 | rcu_read_lock(); | |
a7180877 DDAG |
2670 | |
2671 | if (postcopy_running) { | |
2672 | ret = ram_load_postcopy(f); | |
2673 | } | |
2674 | ||
2675 | while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) { | |
56e93d26 | 2676 | ram_addr_t addr, total_ram_bytes; |
a776aa15 | 2677 | void *host = NULL; |
56e93d26 JQ |
2678 | uint8_t ch; |
2679 | ||
2680 | addr = qemu_get_be64(f); | |
2681 | flags = addr & ~TARGET_PAGE_MASK; | |
2682 | addr &= TARGET_PAGE_MASK; | |
2683 | ||
a776aa15 DDAG |
2684 | if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE | |
2685 | RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) { | |
4c4bad48 HZ |
2686 | RAMBlock *block = ram_block_from_stream(f, flags); |
2687 | ||
2688 | host = host_from_ram_block_offset(block, addr); | |
a776aa15 DDAG |
2689 | if (!host) { |
2690 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); | |
2691 | ret = -EINVAL; | |
2692 | break; | |
2693 | } | |
2694 | } | |
2695 | ||
56e93d26 JQ |
2696 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { |
2697 | case RAM_SAVE_FLAG_MEM_SIZE: | |
2698 | /* Synchronize RAM block list */ | |
2699 | total_ram_bytes = addr; | |
2700 | while (!ret && total_ram_bytes) { | |
2701 | RAMBlock *block; | |
56e93d26 JQ |
2702 | char id[256]; |
2703 | ram_addr_t length; | |
2704 | ||
2705 | len = qemu_get_byte(f); | |
2706 | qemu_get_buffer(f, (uint8_t *)id, len); | |
2707 | id[len] = 0; | |
2708 | length = qemu_get_be64(f); | |
2709 | ||
e3dd7493 DDAG |
2710 | block = qemu_ram_block_by_name(id); |
2711 | if (block) { | |
2712 | if (length != block->used_length) { | |
2713 | Error *local_err = NULL; | |
56e93d26 | 2714 | |
fa53a0e5 | 2715 | ret = qemu_ram_resize(block, length, |
e3dd7493 DDAG |
2716 | &local_err); |
2717 | if (local_err) { | |
2718 | error_report_err(local_err); | |
56e93d26 | 2719 | } |
56e93d26 | 2720 | } |
ef08fb38 DDAG |
2721 | /* For postcopy we need to check hugepage sizes match */ |
2722 | if (postcopy_advised && | |
2723 | block->page_size != qemu_host_page_size) { | |
2724 | uint64_t remote_page_size = qemu_get_be64(f); | |
2725 | if (remote_page_size != block->page_size) { | |
2726 | error_report("Mismatched RAM page size %s " | |
2727 | "(local) %zd != %" PRId64, | |
2728 | id, block->page_size, | |
2729 | remote_page_size); | |
2730 | ret = -EINVAL; | |
2731 | } | |
2732 | } | |
e3dd7493 DDAG |
2733 | ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG, |
2734 | block->idstr); | |
2735 | } else { | |
56e93d26 JQ |
2736 | error_report("Unknown ramblock \"%s\", cannot " |
2737 | "accept migration", id); | |
2738 | ret = -EINVAL; | |
2739 | } | |
2740 | ||
2741 | total_ram_bytes -= length; | |
2742 | } | |
2743 | break; | |
a776aa15 | 2744 | |
56e93d26 | 2745 | case RAM_SAVE_FLAG_COMPRESS: |
56e93d26 JQ |
2746 | ch = qemu_get_byte(f); |
2747 | ram_handle_compressed(host, ch, TARGET_PAGE_SIZE); | |
2748 | break; | |
a776aa15 | 2749 | |
56e93d26 | 2750 | case RAM_SAVE_FLAG_PAGE: |
56e93d26 JQ |
2751 | qemu_get_buffer(f, host, TARGET_PAGE_SIZE); |
2752 | break; | |
56e93d26 | 2753 | |
a776aa15 | 2754 | case RAM_SAVE_FLAG_COMPRESS_PAGE: |
56e93d26 JQ |
2755 | len = qemu_get_be32(f); |
2756 | if (len < 0 || len > compressBound(TARGET_PAGE_SIZE)) { | |
2757 | error_report("Invalid compressed data length: %d", len); | |
2758 | ret = -EINVAL; | |
2759 | break; | |
2760 | } | |
c1bc6626 | 2761 | decompress_data_with_multi_threads(f, host, len); |
56e93d26 | 2762 | break; |
a776aa15 | 2763 | |
56e93d26 | 2764 | case RAM_SAVE_FLAG_XBZRLE: |
56e93d26 JQ |
2765 | if (load_xbzrle(f, addr, host) < 0) { |
2766 | error_report("Failed to decompress XBZRLE page at " | |
2767 | RAM_ADDR_FMT, addr); | |
2768 | ret = -EINVAL; | |
2769 | break; | |
2770 | } | |
2771 | break; | |
2772 | case RAM_SAVE_FLAG_EOS: | |
2773 | /* normal exit */ | |
2774 | break; | |
2775 | default: | |
2776 | if (flags & RAM_SAVE_FLAG_HOOK) { | |
632e3a5c | 2777 | ram_control_load_hook(f, RAM_CONTROL_HOOK, NULL); |
56e93d26 JQ |
2778 | } else { |
2779 | error_report("Unknown combination of migration flags: %#x", | |
2780 | flags); | |
2781 | ret = -EINVAL; | |
2782 | } | |
2783 | } | |
2784 | if (!ret) { | |
2785 | ret = qemu_file_get_error(f); | |
2786 | } | |
2787 | } | |
2788 | ||
5533b2e9 | 2789 | wait_for_decompress_done(); |
56e93d26 | 2790 | rcu_read_unlock(); |
55c4446b | 2791 | trace_ram_load_complete(ret, seq_iter); |
56e93d26 JQ |
2792 | return ret; |
2793 | } | |
2794 | ||
2795 | static SaveVMHandlers savevm_ram_handlers = { | |
2796 | .save_live_setup = ram_save_setup, | |
2797 | .save_live_iterate = ram_save_iterate, | |
763c906b | 2798 | .save_live_complete_postcopy = ram_save_complete, |
a3e06c3d | 2799 | .save_live_complete_precopy = ram_save_complete, |
56e93d26 JQ |
2800 | .save_live_pending = ram_save_pending, |
2801 | .load_state = ram_load, | |
6ad2a215 | 2802 | .cleanup = ram_migration_cleanup, |
56e93d26 JQ |
2803 | }; |
2804 | ||
2805 | void ram_mig_init(void) | |
2806 | { | |
2807 | qemu_mutex_init(&XBZRLE.lock); | |
6f37bb8b | 2808 | register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, &ram_state); |
56e93d26 | 2809 | } |