Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1 | /* |
| 2 | * QEMU System Emulator |
| 3 | * |
| 4 | * Copyright (c) 2003-2008 Fabrice Bellard |
Juan Quintela | 76cc7b5 | 2015-05-08 13:20:21 +0200 | [diff] [blame] | 5 | * Copyright (c) 2011-2015 Red Hat Inc |
| 6 | * |
| 7 | * Authors: |
| 8 | * Juan Quintela <quintela@redhat.com> |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 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 | */ |
Peter Maydell | 1393a48 | 2016-01-26 18:16:54 +0000 | [diff] [blame^] | 28 | #include "qemu/osdep.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 29 | #include <zlib.h> |
Dr. David Alan Gilbert | 4addcd4 | 2015-12-16 11:47:36 +0000 | [diff] [blame] | 30 | #include "qapi-event.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 31 | #include "qemu/bitops.h" |
| 32 | #include "qemu/bitmap.h" |
Juan Quintela | 7205c9e | 2015-05-08 13:54:36 +0200 | [diff] [blame] | 33 | #include "qemu/timer.h" |
| 34 | #include "qemu/main-loop.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 35 | #include "migration/migration.h" |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 36 | #include "migration/postcopy-ram.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 37 | #include "exec/address-spaces.h" |
| 38 | #include "migration/page_cache.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 39 | #include "qemu/error-report.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 40 | #include "trace.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 41 | #include "exec/ram_addr.h" |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 42 | #include "qemu/rcu_queue.h" |
| 43 | |
| 44 | #ifdef DEBUG_MIGRATION_RAM |
| 45 | #define DPRINTF(fmt, ...) \ |
| 46 | do { fprintf(stdout, "migration_ram: " fmt, ## __VA_ARGS__); } while (0) |
| 47 | #else |
| 48 | #define DPRINTF(fmt, ...) \ |
| 49 | do { } while (0) |
| 50 | #endif |
| 51 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 52 | static int dirty_rate_high_cnt; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 53 | |
| 54 | static uint64_t bitmap_sync_count; |
| 55 | |
| 56 | /***********************************************************/ |
| 57 | /* ram save/restore */ |
| 58 | |
| 59 | #define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */ |
| 60 | #define RAM_SAVE_FLAG_COMPRESS 0x02 |
| 61 | #define RAM_SAVE_FLAG_MEM_SIZE 0x04 |
| 62 | #define RAM_SAVE_FLAG_PAGE 0x08 |
| 63 | #define RAM_SAVE_FLAG_EOS 0x10 |
| 64 | #define RAM_SAVE_FLAG_CONTINUE 0x20 |
| 65 | #define RAM_SAVE_FLAG_XBZRLE 0x40 |
| 66 | /* 0x80 is reserved in migration.h start with 0x100 next */ |
| 67 | #define RAM_SAVE_FLAG_COMPRESS_PAGE 0x100 |
| 68 | |
| 69 | static const uint8_t ZERO_TARGET_PAGE[TARGET_PAGE_SIZE]; |
| 70 | |
| 71 | static inline bool is_zero_range(uint8_t *p, uint64_t size) |
| 72 | { |
| 73 | return buffer_find_nonzero_offset(p, size) == size; |
| 74 | } |
| 75 | |
| 76 | /* struct contains XBZRLE cache and a static page |
| 77 | used by the compression */ |
| 78 | static struct { |
| 79 | /* buffer used for XBZRLE encoding */ |
| 80 | uint8_t *encoded_buf; |
| 81 | /* buffer for storing page content */ |
| 82 | uint8_t *current_buf; |
| 83 | /* Cache for XBZRLE, Protected by lock. */ |
| 84 | PageCache *cache; |
| 85 | QemuMutex lock; |
| 86 | } XBZRLE; |
| 87 | |
| 88 | /* buffer used for XBZRLE decoding */ |
| 89 | static uint8_t *xbzrle_decoded_buf; |
| 90 | |
| 91 | static void XBZRLE_cache_lock(void) |
| 92 | { |
| 93 | if (migrate_use_xbzrle()) |
| 94 | qemu_mutex_lock(&XBZRLE.lock); |
| 95 | } |
| 96 | |
| 97 | static void XBZRLE_cache_unlock(void) |
| 98 | { |
| 99 | if (migrate_use_xbzrle()) |
| 100 | qemu_mutex_unlock(&XBZRLE.lock); |
| 101 | } |
| 102 | |
| 103 | /* |
| 104 | * called from qmp_migrate_set_cache_size in main thread, possibly while |
| 105 | * a migration is in progress. |
| 106 | * A running migration maybe using the cache and might finish during this |
| 107 | * call, hence changes to the cache are protected by XBZRLE.lock(). |
| 108 | */ |
| 109 | int64_t xbzrle_cache_resize(int64_t new_size) |
| 110 | { |
| 111 | PageCache *new_cache; |
| 112 | int64_t ret; |
| 113 | |
| 114 | if (new_size < TARGET_PAGE_SIZE) { |
| 115 | return -1; |
| 116 | } |
| 117 | |
| 118 | XBZRLE_cache_lock(); |
| 119 | |
| 120 | if (XBZRLE.cache != NULL) { |
| 121 | if (pow2floor(new_size) == migrate_xbzrle_cache_size()) { |
| 122 | goto out_new_size; |
| 123 | } |
| 124 | new_cache = cache_init(new_size / TARGET_PAGE_SIZE, |
| 125 | TARGET_PAGE_SIZE); |
| 126 | if (!new_cache) { |
| 127 | error_report("Error creating cache"); |
| 128 | ret = -1; |
| 129 | goto out; |
| 130 | } |
| 131 | |
| 132 | cache_fini(XBZRLE.cache); |
| 133 | XBZRLE.cache = new_cache; |
| 134 | } |
| 135 | |
| 136 | out_new_size: |
| 137 | ret = pow2floor(new_size); |
| 138 | out: |
| 139 | XBZRLE_cache_unlock(); |
| 140 | return ret; |
| 141 | } |
| 142 | |
| 143 | /* accounting for migration statistics */ |
| 144 | typedef struct AccountingInfo { |
| 145 | uint64_t dup_pages; |
| 146 | uint64_t skipped_pages; |
| 147 | uint64_t norm_pages; |
| 148 | uint64_t iterations; |
| 149 | uint64_t xbzrle_bytes; |
| 150 | uint64_t xbzrle_pages; |
| 151 | uint64_t xbzrle_cache_miss; |
| 152 | double xbzrle_cache_miss_rate; |
| 153 | uint64_t xbzrle_overflows; |
| 154 | } AccountingInfo; |
| 155 | |
| 156 | static AccountingInfo acct_info; |
| 157 | |
| 158 | static void acct_clear(void) |
| 159 | { |
| 160 | memset(&acct_info, 0, sizeof(acct_info)); |
| 161 | } |
| 162 | |
| 163 | uint64_t dup_mig_bytes_transferred(void) |
| 164 | { |
| 165 | return acct_info.dup_pages * TARGET_PAGE_SIZE; |
| 166 | } |
| 167 | |
| 168 | uint64_t dup_mig_pages_transferred(void) |
| 169 | { |
| 170 | return acct_info.dup_pages; |
| 171 | } |
| 172 | |
| 173 | uint64_t skipped_mig_bytes_transferred(void) |
| 174 | { |
| 175 | return acct_info.skipped_pages * TARGET_PAGE_SIZE; |
| 176 | } |
| 177 | |
| 178 | uint64_t skipped_mig_pages_transferred(void) |
| 179 | { |
| 180 | return acct_info.skipped_pages; |
| 181 | } |
| 182 | |
| 183 | uint64_t norm_mig_bytes_transferred(void) |
| 184 | { |
| 185 | return acct_info.norm_pages * TARGET_PAGE_SIZE; |
| 186 | } |
| 187 | |
| 188 | uint64_t norm_mig_pages_transferred(void) |
| 189 | { |
| 190 | return acct_info.norm_pages; |
| 191 | } |
| 192 | |
| 193 | uint64_t xbzrle_mig_bytes_transferred(void) |
| 194 | { |
| 195 | return acct_info.xbzrle_bytes; |
| 196 | } |
| 197 | |
| 198 | uint64_t xbzrle_mig_pages_transferred(void) |
| 199 | { |
| 200 | return acct_info.xbzrle_pages; |
| 201 | } |
| 202 | |
| 203 | uint64_t xbzrle_mig_pages_cache_miss(void) |
| 204 | { |
| 205 | return acct_info.xbzrle_cache_miss; |
| 206 | } |
| 207 | |
| 208 | double xbzrle_mig_cache_miss_rate(void) |
| 209 | { |
| 210 | return acct_info.xbzrle_cache_miss_rate; |
| 211 | } |
| 212 | |
| 213 | uint64_t xbzrle_mig_pages_overflow(void) |
| 214 | { |
| 215 | return acct_info.xbzrle_overflows; |
| 216 | } |
| 217 | |
| 218 | /* This is the last block that we have visited serching for dirty pages |
| 219 | */ |
| 220 | static RAMBlock *last_seen_block; |
| 221 | /* This is the last block from where we have sent data */ |
| 222 | static RAMBlock *last_sent_block; |
| 223 | static ram_addr_t last_offset; |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 224 | static QemuMutex migration_bitmap_mutex; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 225 | static uint64_t migration_dirty_pages; |
| 226 | static uint32_t last_version; |
| 227 | static bool ram_bulk_stage; |
| 228 | |
Dr. David Alan Gilbert | b8fb8cb | 2015-09-23 15:27:10 +0100 | [diff] [blame] | 229 | /* used by the search for pages to send */ |
| 230 | struct PageSearchStatus { |
| 231 | /* Current block being searched */ |
| 232 | RAMBlock *block; |
| 233 | /* Current offset to search from */ |
| 234 | ram_addr_t offset; |
| 235 | /* Set once we wrap around */ |
| 236 | bool complete_round; |
| 237 | }; |
| 238 | typedef struct PageSearchStatus PageSearchStatus; |
| 239 | |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 240 | static struct BitmapRcu { |
| 241 | struct rcu_head rcu; |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 242 | /* Main migration bitmap */ |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 243 | unsigned long *bmap; |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 244 | /* bitmap of pages that haven't been sent even once |
| 245 | * only maintained and used in postcopy at the moment |
| 246 | * where it's used to send the dirtymap at the start |
| 247 | * of the postcopy phase |
| 248 | */ |
| 249 | unsigned long *unsentmap; |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 250 | } *migration_bitmap_rcu; |
| 251 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 252 | struct CompressParam { |
| 253 | bool start; |
| 254 | bool done; |
| 255 | QEMUFile *file; |
| 256 | QemuMutex mutex; |
| 257 | QemuCond cond; |
| 258 | RAMBlock *block; |
| 259 | ram_addr_t offset; |
| 260 | }; |
| 261 | typedef struct CompressParam CompressParam; |
| 262 | |
| 263 | struct DecompressParam { |
| 264 | bool start; |
| 265 | QemuMutex mutex; |
| 266 | QemuCond cond; |
| 267 | void *des; |
Peter Maydell | d341d9f | 2016-01-22 15:09:21 +0000 | [diff] [blame] | 268 | uint8_t *compbuf; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 269 | int len; |
| 270 | }; |
| 271 | typedef struct DecompressParam DecompressParam; |
| 272 | |
| 273 | static CompressParam *comp_param; |
| 274 | static QemuThread *compress_threads; |
| 275 | /* comp_done_cond is used to wake up the migration thread when |
| 276 | * one of the compression threads has finished the compression. |
| 277 | * comp_done_lock is used to co-work with comp_done_cond. |
| 278 | */ |
| 279 | static QemuMutex *comp_done_lock; |
| 280 | static QemuCond *comp_done_cond; |
| 281 | /* The empty QEMUFileOps will be used by file in CompressParam */ |
| 282 | static const QEMUFileOps empty_ops = { }; |
| 283 | |
| 284 | static bool compression_switch; |
| 285 | static bool quit_comp_thread; |
| 286 | static bool quit_decomp_thread; |
| 287 | static DecompressParam *decomp_param; |
| 288 | static QemuThread *decompress_threads; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 289 | |
| 290 | static int do_compress_ram_page(CompressParam *param); |
| 291 | |
| 292 | static void *do_data_compress(void *opaque) |
| 293 | { |
| 294 | CompressParam *param = opaque; |
| 295 | |
| 296 | while (!quit_comp_thread) { |
| 297 | qemu_mutex_lock(¶m->mutex); |
| 298 | /* Re-check the quit_comp_thread in case of |
| 299 | * terminate_compression_threads is called just before |
| 300 | * qemu_mutex_lock(¶m->mutex) and after |
| 301 | * while(!quit_comp_thread), re-check it here can make |
| 302 | * sure the compression thread terminate as expected. |
| 303 | */ |
| 304 | while (!param->start && !quit_comp_thread) { |
| 305 | qemu_cond_wait(¶m->cond, ¶m->mutex); |
| 306 | } |
| 307 | if (!quit_comp_thread) { |
| 308 | do_compress_ram_page(param); |
| 309 | } |
| 310 | param->start = false; |
| 311 | qemu_mutex_unlock(¶m->mutex); |
| 312 | |
| 313 | qemu_mutex_lock(comp_done_lock); |
| 314 | param->done = true; |
| 315 | qemu_cond_signal(comp_done_cond); |
| 316 | qemu_mutex_unlock(comp_done_lock); |
| 317 | } |
| 318 | |
| 319 | return NULL; |
| 320 | } |
| 321 | |
| 322 | static inline void terminate_compression_threads(void) |
| 323 | { |
| 324 | int idx, thread_count; |
| 325 | |
| 326 | thread_count = migrate_compress_threads(); |
| 327 | quit_comp_thread = true; |
| 328 | for (idx = 0; idx < thread_count; idx++) { |
| 329 | qemu_mutex_lock(&comp_param[idx].mutex); |
| 330 | qemu_cond_signal(&comp_param[idx].cond); |
| 331 | qemu_mutex_unlock(&comp_param[idx].mutex); |
| 332 | } |
| 333 | } |
| 334 | |
| 335 | void migrate_compress_threads_join(void) |
| 336 | { |
| 337 | int i, thread_count; |
| 338 | |
| 339 | if (!migrate_use_compression()) { |
| 340 | return; |
| 341 | } |
| 342 | terminate_compression_threads(); |
| 343 | thread_count = migrate_compress_threads(); |
| 344 | for (i = 0; i < thread_count; i++) { |
| 345 | qemu_thread_join(compress_threads + i); |
| 346 | qemu_fclose(comp_param[i].file); |
| 347 | qemu_mutex_destroy(&comp_param[i].mutex); |
| 348 | qemu_cond_destroy(&comp_param[i].cond); |
| 349 | } |
| 350 | qemu_mutex_destroy(comp_done_lock); |
| 351 | qemu_cond_destroy(comp_done_cond); |
| 352 | g_free(compress_threads); |
| 353 | g_free(comp_param); |
| 354 | g_free(comp_done_cond); |
| 355 | g_free(comp_done_lock); |
| 356 | compress_threads = NULL; |
| 357 | comp_param = NULL; |
| 358 | comp_done_cond = NULL; |
| 359 | comp_done_lock = NULL; |
| 360 | } |
| 361 | |
| 362 | void migrate_compress_threads_create(void) |
| 363 | { |
| 364 | int i, thread_count; |
| 365 | |
| 366 | if (!migrate_use_compression()) { |
| 367 | return; |
| 368 | } |
| 369 | quit_comp_thread = false; |
| 370 | compression_switch = true; |
| 371 | thread_count = migrate_compress_threads(); |
| 372 | compress_threads = g_new0(QemuThread, thread_count); |
| 373 | comp_param = g_new0(CompressParam, thread_count); |
| 374 | comp_done_cond = g_new0(QemuCond, 1); |
| 375 | comp_done_lock = g_new0(QemuMutex, 1); |
| 376 | qemu_cond_init(comp_done_cond); |
| 377 | qemu_mutex_init(comp_done_lock); |
| 378 | for (i = 0; i < thread_count; i++) { |
| 379 | /* com_param[i].file is just used as a dummy buffer to save data, set |
| 380 | * it's ops to empty. |
| 381 | */ |
| 382 | comp_param[i].file = qemu_fopen_ops(NULL, &empty_ops); |
| 383 | comp_param[i].done = true; |
| 384 | qemu_mutex_init(&comp_param[i].mutex); |
| 385 | qemu_cond_init(&comp_param[i].cond); |
| 386 | qemu_thread_create(compress_threads + i, "compress", |
| 387 | do_data_compress, comp_param + i, |
| 388 | QEMU_THREAD_JOINABLE); |
| 389 | } |
| 390 | } |
| 391 | |
| 392 | /** |
| 393 | * save_page_header: Write page header to wire |
| 394 | * |
| 395 | * If this is the 1st block, it also writes the block identification |
| 396 | * |
| 397 | * Returns: Number of bytes written |
| 398 | * |
| 399 | * @f: QEMUFile where to send the data |
| 400 | * @block: block that contains the page we want to send |
| 401 | * @offset: offset inside the block for the page |
| 402 | * in the lower bits, it contains flags |
| 403 | */ |
| 404 | static size_t save_page_header(QEMUFile *f, RAMBlock *block, ram_addr_t offset) |
| 405 | { |
Liang Li | 9f5f380 | 2015-07-13 17:34:10 +0800 | [diff] [blame] | 406 | size_t size, len; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 407 | |
| 408 | qemu_put_be64(f, offset); |
| 409 | size = 8; |
| 410 | |
| 411 | if (!(offset & RAM_SAVE_FLAG_CONTINUE)) { |
Liang Li | 9f5f380 | 2015-07-13 17:34:10 +0800 | [diff] [blame] | 412 | len = strlen(block->idstr); |
| 413 | qemu_put_byte(f, len); |
| 414 | qemu_put_buffer(f, (uint8_t *)block->idstr, len); |
| 415 | size += 1 + len; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 416 | } |
| 417 | return size; |
| 418 | } |
| 419 | |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 420 | /* Reduce amount of guest cpu execution to hopefully slow down memory writes. |
| 421 | * If guest dirty memory rate is reduced below the rate at which we can |
| 422 | * transfer pages to the destination then we should be able to complete |
| 423 | * migration. Some workloads dirty memory way too fast and will not effectively |
| 424 | * converge, even with auto-converge. |
| 425 | */ |
| 426 | static void mig_throttle_guest_down(void) |
| 427 | { |
| 428 | MigrationState *s = migrate_get_current(); |
| 429 | uint64_t pct_initial = |
| 430 | s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL]; |
| 431 | uint64_t pct_icrement = |
| 432 | s->parameters[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT]; |
| 433 | |
| 434 | /* We have not started throttling yet. Let's start it. */ |
| 435 | if (!cpu_throttle_active()) { |
| 436 | cpu_throttle_set(pct_initial); |
| 437 | } else { |
| 438 | /* Throttling already on, just increase the rate */ |
| 439 | cpu_throttle_set(cpu_throttle_get_percentage() + pct_icrement); |
| 440 | } |
| 441 | } |
| 442 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 443 | /* Update the xbzrle cache to reflect a page that's been sent as all 0. |
| 444 | * The important thing is that a stale (not-yet-0'd) page be replaced |
| 445 | * by the new data. |
| 446 | * As a bonus, if the page wasn't in the cache it gets added so that |
| 447 | * when a small write is made into the 0'd page it gets XBZRLE sent |
| 448 | */ |
| 449 | static void xbzrle_cache_zero_page(ram_addr_t current_addr) |
| 450 | { |
| 451 | if (ram_bulk_stage || !migrate_use_xbzrle()) { |
| 452 | return; |
| 453 | } |
| 454 | |
| 455 | /* We don't care if this fails to allocate a new cache page |
| 456 | * as long as it updated an old one */ |
| 457 | cache_insert(XBZRLE.cache, current_addr, ZERO_TARGET_PAGE, |
| 458 | bitmap_sync_count); |
| 459 | } |
| 460 | |
| 461 | #define ENCODING_FLAG_XBZRLE 0x1 |
| 462 | |
| 463 | /** |
| 464 | * save_xbzrle_page: compress and send current page |
| 465 | * |
| 466 | * Returns: 1 means that we wrote the page |
| 467 | * 0 means that page is identical to the one already sent |
| 468 | * -1 means that xbzrle would be longer than normal |
| 469 | * |
| 470 | * @f: QEMUFile where to send the data |
| 471 | * @current_data: |
| 472 | * @current_addr: |
| 473 | * @block: block that contains the page we want to send |
| 474 | * @offset: offset inside the block for the page |
| 475 | * @last_stage: if we are at the completion stage |
| 476 | * @bytes_transferred: increase it with the number of transferred bytes |
| 477 | */ |
| 478 | static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data, |
| 479 | ram_addr_t current_addr, RAMBlock *block, |
| 480 | ram_addr_t offset, bool last_stage, |
| 481 | uint64_t *bytes_transferred) |
| 482 | { |
| 483 | int encoded_len = 0, bytes_xbzrle; |
| 484 | uint8_t *prev_cached_page; |
| 485 | |
| 486 | if (!cache_is_cached(XBZRLE.cache, current_addr, bitmap_sync_count)) { |
| 487 | acct_info.xbzrle_cache_miss++; |
| 488 | if (!last_stage) { |
| 489 | if (cache_insert(XBZRLE.cache, current_addr, *current_data, |
| 490 | bitmap_sync_count) == -1) { |
| 491 | return -1; |
| 492 | } else { |
| 493 | /* update *current_data when the page has been |
| 494 | inserted into cache */ |
| 495 | *current_data = get_cached_data(XBZRLE.cache, current_addr); |
| 496 | } |
| 497 | } |
| 498 | return -1; |
| 499 | } |
| 500 | |
| 501 | prev_cached_page = get_cached_data(XBZRLE.cache, current_addr); |
| 502 | |
| 503 | /* save current buffer into memory */ |
| 504 | memcpy(XBZRLE.current_buf, *current_data, TARGET_PAGE_SIZE); |
| 505 | |
| 506 | /* XBZRLE encoding (if there is no overflow) */ |
| 507 | encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf, |
| 508 | TARGET_PAGE_SIZE, XBZRLE.encoded_buf, |
| 509 | TARGET_PAGE_SIZE); |
| 510 | if (encoded_len == 0) { |
| 511 | DPRINTF("Skipping unmodified page\n"); |
| 512 | return 0; |
| 513 | } else if (encoded_len == -1) { |
| 514 | DPRINTF("Overflow\n"); |
| 515 | acct_info.xbzrle_overflows++; |
| 516 | /* update data in the cache */ |
| 517 | if (!last_stage) { |
| 518 | memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE); |
| 519 | *current_data = prev_cached_page; |
| 520 | } |
| 521 | return -1; |
| 522 | } |
| 523 | |
| 524 | /* we need to update the data in the cache, in order to get the same data */ |
| 525 | if (!last_stage) { |
| 526 | memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); |
| 527 | } |
| 528 | |
| 529 | /* Send XBZRLE based compressed page */ |
| 530 | bytes_xbzrle = save_page_header(f, block, offset | RAM_SAVE_FLAG_XBZRLE); |
| 531 | qemu_put_byte(f, ENCODING_FLAG_XBZRLE); |
| 532 | qemu_put_be16(f, encoded_len); |
| 533 | qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len); |
| 534 | bytes_xbzrle += encoded_len + 1 + 2; |
| 535 | acct_info.xbzrle_pages++; |
| 536 | acct_info.xbzrle_bytes += bytes_xbzrle; |
| 537 | *bytes_transferred += bytes_xbzrle; |
| 538 | |
| 539 | return 1; |
| 540 | } |
| 541 | |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 542 | /* Called with rcu_read_lock() to protect migration_bitmap |
| 543 | * rb: The RAMBlock to search for dirty pages in |
| 544 | * start: Start address (typically so we can continue from previous page) |
| 545 | * ram_addr_abs: Pointer into which to store the address of the dirty page |
| 546 | * within the global ram_addr space |
| 547 | * |
| 548 | * Returns: byte offset within memory region of the start of a dirty page |
| 549 | */ |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 550 | static inline |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 551 | ram_addr_t migration_bitmap_find_dirty(RAMBlock *rb, |
| 552 | ram_addr_t start, |
| 553 | ram_addr_t *ram_addr_abs) |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 554 | { |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 555 | unsigned long base = rb->offset >> TARGET_PAGE_BITS; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 556 | unsigned long nr = base + (start >> TARGET_PAGE_BITS); |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 557 | uint64_t rb_size = rb->used_length; |
| 558 | unsigned long size = base + (rb_size >> TARGET_PAGE_BITS); |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 559 | unsigned long *bitmap; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 560 | |
| 561 | unsigned long next; |
| 562 | |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 563 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 564 | if (ram_bulk_stage && nr > base) { |
| 565 | next = nr + 1; |
| 566 | } else { |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 567 | next = find_next_bit(bitmap, size, nr); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 568 | } |
| 569 | |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 570 | *ram_addr_abs = next << TARGET_PAGE_BITS; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 571 | return (next - base) << TARGET_PAGE_BITS; |
| 572 | } |
| 573 | |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 574 | static inline bool migration_bitmap_clear_dirty(ram_addr_t addr) |
| 575 | { |
| 576 | bool ret; |
| 577 | int nr = addr >> TARGET_PAGE_BITS; |
| 578 | unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
| 579 | |
| 580 | ret = test_and_clear_bit(nr, bitmap); |
| 581 | |
| 582 | if (ret) { |
| 583 | migration_dirty_pages--; |
| 584 | } |
| 585 | return ret; |
| 586 | } |
| 587 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 588 | static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length) |
| 589 | { |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 590 | unsigned long *bitmap; |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 591 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 592 | migration_dirty_pages += |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 593 | cpu_physical_memory_sync_dirty_bitmap(bitmap, start, length); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 594 | } |
| 595 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 596 | /* Fix me: there are too many global variables used in migration process. */ |
| 597 | static int64_t start_time; |
| 598 | static int64_t bytes_xfer_prev; |
| 599 | static int64_t num_dirty_pages_period; |
| 600 | static uint64_t xbzrle_cache_miss_prev; |
| 601 | static uint64_t iterations_prev; |
| 602 | |
| 603 | static void migration_bitmap_sync_init(void) |
| 604 | { |
| 605 | start_time = 0; |
| 606 | bytes_xfer_prev = 0; |
| 607 | num_dirty_pages_period = 0; |
| 608 | xbzrle_cache_miss_prev = 0; |
| 609 | iterations_prev = 0; |
| 610 | } |
| 611 | |
| 612 | /* Called with iothread lock held, to protect ram_list.dirty_memory[] */ |
| 613 | static void migration_bitmap_sync(void) |
| 614 | { |
| 615 | RAMBlock *block; |
| 616 | uint64_t num_dirty_pages_init = migration_dirty_pages; |
| 617 | MigrationState *s = migrate_get_current(); |
| 618 | int64_t end_time; |
| 619 | int64_t bytes_xfer_now; |
| 620 | |
| 621 | bitmap_sync_count++; |
| 622 | |
| 623 | if (!bytes_xfer_prev) { |
| 624 | bytes_xfer_prev = ram_bytes_transferred(); |
| 625 | } |
| 626 | |
| 627 | if (!start_time) { |
| 628 | start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); |
| 629 | } |
| 630 | |
| 631 | trace_migration_bitmap_sync_start(); |
| 632 | address_space_sync_dirty_bitmap(&address_space_memory); |
| 633 | |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 634 | qemu_mutex_lock(&migration_bitmap_mutex); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 635 | rcu_read_lock(); |
| 636 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 637 | migration_bitmap_sync_range(block->offset, block->used_length); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 638 | } |
| 639 | rcu_read_unlock(); |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 640 | qemu_mutex_unlock(&migration_bitmap_mutex); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 641 | |
| 642 | trace_migration_bitmap_sync_end(migration_dirty_pages |
| 643 | - num_dirty_pages_init); |
| 644 | num_dirty_pages_period += migration_dirty_pages - num_dirty_pages_init; |
| 645 | end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); |
| 646 | |
| 647 | /* more than 1 second = 1000 millisecons */ |
| 648 | if (end_time > start_time + 1000) { |
| 649 | if (migrate_auto_converge()) { |
| 650 | /* The following detection logic can be refined later. For now: |
| 651 | Check to see if the dirtied bytes is 50% more than the approx. |
| 652 | amount of bytes that just got transferred since the last time we |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 653 | were in this routine. If that happens twice, start or increase |
| 654 | throttling */ |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 655 | bytes_xfer_now = ram_bytes_transferred(); |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 656 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 657 | if (s->dirty_pages_rate && |
| 658 | (num_dirty_pages_period * TARGET_PAGE_SIZE > |
| 659 | (bytes_xfer_now - bytes_xfer_prev)/2) && |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 660 | (dirty_rate_high_cnt++ >= 2)) { |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 661 | trace_migration_throttle(); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 662 | dirty_rate_high_cnt = 0; |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 663 | mig_throttle_guest_down(); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 664 | } |
| 665 | bytes_xfer_prev = bytes_xfer_now; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 666 | } |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 667 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 668 | if (migrate_use_xbzrle()) { |
| 669 | if (iterations_prev != acct_info.iterations) { |
| 670 | acct_info.xbzrle_cache_miss_rate = |
| 671 | (double)(acct_info.xbzrle_cache_miss - |
| 672 | xbzrle_cache_miss_prev) / |
| 673 | (acct_info.iterations - iterations_prev); |
| 674 | } |
| 675 | iterations_prev = acct_info.iterations; |
| 676 | xbzrle_cache_miss_prev = acct_info.xbzrle_cache_miss; |
| 677 | } |
| 678 | s->dirty_pages_rate = num_dirty_pages_period * 1000 |
| 679 | / (end_time - start_time); |
| 680 | s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE; |
| 681 | start_time = end_time; |
| 682 | num_dirty_pages_period = 0; |
| 683 | } |
| 684 | s->dirty_sync_count = bitmap_sync_count; |
Dr. David Alan Gilbert | 4addcd4 | 2015-12-16 11:47:36 +0000 | [diff] [blame] | 685 | if (migrate_use_events()) { |
| 686 | qapi_event_send_migration_pass(bitmap_sync_count, NULL); |
| 687 | } |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 688 | } |
| 689 | |
| 690 | /** |
| 691 | * save_zero_page: Send the zero page to the stream |
| 692 | * |
| 693 | * Returns: Number of pages written. |
| 694 | * |
| 695 | * @f: QEMUFile where to send the data |
| 696 | * @block: block that contains the page we want to send |
| 697 | * @offset: offset inside the block for the page |
| 698 | * @p: pointer to the page |
| 699 | * @bytes_transferred: increase it with the number of transferred bytes |
| 700 | */ |
| 701 | static int save_zero_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset, |
| 702 | uint8_t *p, uint64_t *bytes_transferred) |
| 703 | { |
| 704 | int pages = -1; |
| 705 | |
| 706 | if (is_zero_range(p, TARGET_PAGE_SIZE)) { |
| 707 | acct_info.dup_pages++; |
| 708 | *bytes_transferred += save_page_header(f, block, |
| 709 | offset | RAM_SAVE_FLAG_COMPRESS); |
| 710 | qemu_put_byte(f, 0); |
| 711 | *bytes_transferred += 1; |
| 712 | pages = 1; |
| 713 | } |
| 714 | |
| 715 | return pages; |
| 716 | } |
| 717 | |
| 718 | /** |
| 719 | * ram_save_page: Send the given page to the stream |
| 720 | * |
| 721 | * Returns: Number of pages written. |
Dr. David Alan Gilbert | 3fd3c4b | 2015-12-10 16:31:46 +0000 | [diff] [blame] | 722 | * < 0 - error |
| 723 | * >=0 - Number of pages written - this might legally be 0 |
| 724 | * if xbzrle noticed the page was the same. |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 725 | * |
| 726 | * @f: QEMUFile where to send the data |
| 727 | * @block: block that contains the page we want to send |
| 728 | * @offset: offset inside the block for the page |
| 729 | * @last_stage: if we are at the completion stage |
| 730 | * @bytes_transferred: increase it with the number of transferred bytes |
| 731 | */ |
| 732 | static int ram_save_page(QEMUFile *f, RAMBlock* block, ram_addr_t offset, |
| 733 | bool last_stage, uint64_t *bytes_transferred) |
| 734 | { |
| 735 | int pages = -1; |
| 736 | uint64_t bytes_xmit; |
| 737 | ram_addr_t current_addr; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 738 | uint8_t *p; |
| 739 | int ret; |
| 740 | bool send_async = true; |
| 741 | |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 742 | p = block->host + offset; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 743 | |
| 744 | /* In doubt sent page as normal */ |
| 745 | bytes_xmit = 0; |
| 746 | ret = ram_control_save_page(f, block->offset, |
| 747 | offset, TARGET_PAGE_SIZE, &bytes_xmit); |
| 748 | if (bytes_xmit) { |
| 749 | *bytes_transferred += bytes_xmit; |
| 750 | pages = 1; |
| 751 | } |
| 752 | |
| 753 | XBZRLE_cache_lock(); |
| 754 | |
| 755 | current_addr = block->offset + offset; |
| 756 | |
| 757 | if (block == last_sent_block) { |
| 758 | offset |= RAM_SAVE_FLAG_CONTINUE; |
| 759 | } |
| 760 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
| 761 | if (ret != RAM_SAVE_CONTROL_DELAYED) { |
| 762 | if (bytes_xmit > 0) { |
| 763 | acct_info.norm_pages++; |
| 764 | } else if (bytes_xmit == 0) { |
| 765 | acct_info.dup_pages++; |
| 766 | } |
| 767 | } |
| 768 | } else { |
| 769 | pages = save_zero_page(f, block, offset, p, bytes_transferred); |
| 770 | if (pages > 0) { |
| 771 | /* Must let xbzrle know, otherwise a previous (now 0'd) cached |
| 772 | * page would be stale |
| 773 | */ |
| 774 | xbzrle_cache_zero_page(current_addr); |
| 775 | } else if (!ram_bulk_stage && migrate_use_xbzrle()) { |
| 776 | pages = save_xbzrle_page(f, &p, current_addr, block, |
| 777 | offset, last_stage, bytes_transferred); |
| 778 | if (!last_stage) { |
| 779 | /* Can't send this cached data async, since the cache page |
| 780 | * might get updated before it gets to the wire |
| 781 | */ |
| 782 | send_async = false; |
| 783 | } |
| 784 | } |
| 785 | } |
| 786 | |
| 787 | /* XBZRLE overflow or normal page */ |
| 788 | if (pages == -1) { |
| 789 | *bytes_transferred += save_page_header(f, block, |
| 790 | offset | RAM_SAVE_FLAG_PAGE); |
| 791 | if (send_async) { |
| 792 | qemu_put_buffer_async(f, p, TARGET_PAGE_SIZE); |
| 793 | } else { |
| 794 | qemu_put_buffer(f, p, TARGET_PAGE_SIZE); |
| 795 | } |
| 796 | *bytes_transferred += TARGET_PAGE_SIZE; |
| 797 | pages = 1; |
| 798 | acct_info.norm_pages++; |
| 799 | } |
| 800 | |
| 801 | XBZRLE_cache_unlock(); |
| 802 | |
| 803 | return pages; |
| 804 | } |
| 805 | |
| 806 | static int do_compress_ram_page(CompressParam *param) |
| 807 | { |
| 808 | int bytes_sent, blen; |
| 809 | uint8_t *p; |
| 810 | RAMBlock *block = param->block; |
| 811 | ram_addr_t offset = param->offset; |
| 812 | |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 813 | p = block->host + (offset & TARGET_PAGE_MASK); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 814 | |
| 815 | bytes_sent = save_page_header(param->file, block, offset | |
| 816 | RAM_SAVE_FLAG_COMPRESS_PAGE); |
| 817 | blen = qemu_put_compression_data(param->file, p, TARGET_PAGE_SIZE, |
| 818 | migrate_compress_level()); |
| 819 | bytes_sent += blen; |
| 820 | |
| 821 | return bytes_sent; |
| 822 | } |
| 823 | |
| 824 | static inline void start_compression(CompressParam *param) |
| 825 | { |
| 826 | param->done = false; |
| 827 | qemu_mutex_lock(¶m->mutex); |
| 828 | param->start = true; |
| 829 | qemu_cond_signal(¶m->cond); |
| 830 | qemu_mutex_unlock(¶m->mutex); |
| 831 | } |
| 832 | |
| 833 | static inline void start_decompression(DecompressParam *param) |
| 834 | { |
| 835 | qemu_mutex_lock(¶m->mutex); |
| 836 | param->start = true; |
| 837 | qemu_cond_signal(¶m->cond); |
| 838 | qemu_mutex_unlock(¶m->mutex); |
| 839 | } |
| 840 | |
| 841 | static uint64_t bytes_transferred; |
| 842 | |
| 843 | static void flush_compressed_data(QEMUFile *f) |
| 844 | { |
| 845 | int idx, len, thread_count; |
| 846 | |
| 847 | if (!migrate_use_compression()) { |
| 848 | return; |
| 849 | } |
| 850 | thread_count = migrate_compress_threads(); |
| 851 | for (idx = 0; idx < thread_count; idx++) { |
| 852 | if (!comp_param[idx].done) { |
| 853 | qemu_mutex_lock(comp_done_lock); |
| 854 | while (!comp_param[idx].done && !quit_comp_thread) { |
| 855 | qemu_cond_wait(comp_done_cond, comp_done_lock); |
| 856 | } |
| 857 | qemu_mutex_unlock(comp_done_lock); |
| 858 | } |
| 859 | if (!quit_comp_thread) { |
| 860 | len = qemu_put_qemu_file(f, comp_param[idx].file); |
| 861 | bytes_transferred += len; |
| 862 | } |
| 863 | } |
| 864 | } |
| 865 | |
| 866 | static inline void set_compress_params(CompressParam *param, RAMBlock *block, |
| 867 | ram_addr_t offset) |
| 868 | { |
| 869 | param->block = block; |
| 870 | param->offset = offset; |
| 871 | } |
| 872 | |
| 873 | static int compress_page_with_multi_thread(QEMUFile *f, RAMBlock *block, |
| 874 | ram_addr_t offset, |
| 875 | uint64_t *bytes_transferred) |
| 876 | { |
| 877 | int idx, thread_count, bytes_xmit = -1, pages = -1; |
| 878 | |
| 879 | thread_count = migrate_compress_threads(); |
| 880 | qemu_mutex_lock(comp_done_lock); |
| 881 | while (true) { |
| 882 | for (idx = 0; idx < thread_count; idx++) { |
| 883 | if (comp_param[idx].done) { |
| 884 | bytes_xmit = qemu_put_qemu_file(f, comp_param[idx].file); |
| 885 | set_compress_params(&comp_param[idx], block, offset); |
| 886 | start_compression(&comp_param[idx]); |
| 887 | pages = 1; |
| 888 | acct_info.norm_pages++; |
| 889 | *bytes_transferred += bytes_xmit; |
| 890 | break; |
| 891 | } |
| 892 | } |
| 893 | if (pages > 0) { |
| 894 | break; |
| 895 | } else { |
| 896 | qemu_cond_wait(comp_done_cond, comp_done_lock); |
| 897 | } |
| 898 | } |
| 899 | qemu_mutex_unlock(comp_done_lock); |
| 900 | |
| 901 | return pages; |
| 902 | } |
| 903 | |
| 904 | /** |
| 905 | * ram_save_compressed_page: compress the given page and send it to the stream |
| 906 | * |
| 907 | * Returns: Number of pages written. |
| 908 | * |
| 909 | * @f: QEMUFile where to send the data |
| 910 | * @block: block that contains the page we want to send |
| 911 | * @offset: offset inside the block for the page |
| 912 | * @last_stage: if we are at the completion stage |
| 913 | * @bytes_transferred: increase it with the number of transferred bytes |
| 914 | */ |
| 915 | static int ram_save_compressed_page(QEMUFile *f, RAMBlock *block, |
| 916 | ram_addr_t offset, bool last_stage, |
| 917 | uint64_t *bytes_transferred) |
| 918 | { |
| 919 | int pages = -1; |
| 920 | uint64_t bytes_xmit; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 921 | uint8_t *p; |
| 922 | int ret; |
| 923 | |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 924 | p = block->host + offset; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 925 | |
| 926 | bytes_xmit = 0; |
| 927 | ret = ram_control_save_page(f, block->offset, |
| 928 | offset, TARGET_PAGE_SIZE, &bytes_xmit); |
| 929 | if (bytes_xmit) { |
| 930 | *bytes_transferred += bytes_xmit; |
| 931 | pages = 1; |
| 932 | } |
| 933 | if (block == last_sent_block) { |
| 934 | offset |= RAM_SAVE_FLAG_CONTINUE; |
| 935 | } |
| 936 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
| 937 | if (ret != RAM_SAVE_CONTROL_DELAYED) { |
| 938 | if (bytes_xmit > 0) { |
| 939 | acct_info.norm_pages++; |
| 940 | } else if (bytes_xmit == 0) { |
| 941 | acct_info.dup_pages++; |
| 942 | } |
| 943 | } |
| 944 | } else { |
| 945 | /* When starting the process of a new block, the first page of |
| 946 | * the block should be sent out before other pages in the same |
| 947 | * block, and all the pages in last block should have been sent |
| 948 | * out, keeping this order is important, because the 'cont' flag |
| 949 | * is used to avoid resending the block name. |
| 950 | */ |
| 951 | if (block != last_sent_block) { |
| 952 | flush_compressed_data(f); |
| 953 | pages = save_zero_page(f, block, offset, p, bytes_transferred); |
| 954 | if (pages == -1) { |
| 955 | set_compress_params(&comp_param[0], block, offset); |
| 956 | /* Use the qemu thread to compress the data to make sure the |
| 957 | * first page is sent out before other pages |
| 958 | */ |
| 959 | bytes_xmit = do_compress_ram_page(&comp_param[0]); |
| 960 | acct_info.norm_pages++; |
| 961 | qemu_put_qemu_file(f, comp_param[0].file); |
| 962 | *bytes_transferred += bytes_xmit; |
| 963 | pages = 1; |
| 964 | } |
| 965 | } else { |
| 966 | pages = save_zero_page(f, block, offset, p, bytes_transferred); |
| 967 | if (pages == -1) { |
| 968 | pages = compress_page_with_multi_thread(f, block, offset, |
| 969 | bytes_transferred); |
| 970 | } |
| 971 | } |
| 972 | } |
| 973 | |
| 974 | return pages; |
| 975 | } |
| 976 | |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 977 | /* |
| 978 | * Find the next dirty page and update any state associated with |
| 979 | * the search process. |
| 980 | * |
| 981 | * Returns: True if a page is found |
| 982 | * |
| 983 | * @f: Current migration stream. |
| 984 | * @pss: Data about the state of the current dirty page scan. |
| 985 | * @*again: Set to false if the search has scanned the whole of RAM |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 986 | * *ram_addr_abs: Pointer into which to store the address of the dirty page |
| 987 | * within the global ram_addr space |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 988 | */ |
| 989 | static bool find_dirty_block(QEMUFile *f, PageSearchStatus *pss, |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 990 | bool *again, ram_addr_t *ram_addr_abs) |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 991 | { |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 992 | pss->offset = migration_bitmap_find_dirty(pss->block, pss->offset, |
| 993 | ram_addr_abs); |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 994 | if (pss->complete_round && pss->block == last_seen_block && |
| 995 | pss->offset >= last_offset) { |
| 996 | /* |
| 997 | * We've been once around the RAM and haven't found anything. |
| 998 | * Give up. |
| 999 | */ |
| 1000 | *again = false; |
| 1001 | return false; |
| 1002 | } |
| 1003 | if (pss->offset >= pss->block->used_length) { |
| 1004 | /* Didn't find anything in this RAM Block */ |
| 1005 | pss->offset = 0; |
| 1006 | pss->block = QLIST_NEXT_RCU(pss->block, next); |
| 1007 | if (!pss->block) { |
| 1008 | /* Hit the end of the list */ |
| 1009 | pss->block = QLIST_FIRST_RCU(&ram_list.blocks); |
| 1010 | /* Flag that we've looped */ |
| 1011 | pss->complete_round = true; |
| 1012 | ram_bulk_stage = false; |
| 1013 | if (migrate_use_xbzrle()) { |
| 1014 | /* If xbzrle is on, stop using the data compression at this |
| 1015 | * point. In theory, xbzrle can do better than compression. |
| 1016 | */ |
| 1017 | flush_compressed_data(f); |
| 1018 | compression_switch = false; |
| 1019 | } |
| 1020 | } |
| 1021 | /* Didn't find anything this time, but try again on the new block */ |
| 1022 | *again = true; |
| 1023 | return false; |
| 1024 | } else { |
| 1025 | /* Can go around again, but... */ |
| 1026 | *again = true; |
| 1027 | /* We've found something so probably don't need to */ |
| 1028 | return true; |
| 1029 | } |
| 1030 | } |
| 1031 | |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1032 | /* |
| 1033 | * Helper for 'get_queued_page' - gets a page off the queue |
| 1034 | * ms: MigrationState in |
| 1035 | * *offset: Used to return the offset within the RAMBlock |
| 1036 | * ram_addr_abs: global offset in the dirty/sent bitmaps |
| 1037 | * |
| 1038 | * Returns: block (or NULL if none available) |
| 1039 | */ |
| 1040 | static RAMBlock *unqueue_page(MigrationState *ms, ram_addr_t *offset, |
| 1041 | ram_addr_t *ram_addr_abs) |
| 1042 | { |
| 1043 | RAMBlock *block = NULL; |
| 1044 | |
| 1045 | qemu_mutex_lock(&ms->src_page_req_mutex); |
| 1046 | if (!QSIMPLEQ_EMPTY(&ms->src_page_requests)) { |
| 1047 | struct MigrationSrcPageRequest *entry = |
| 1048 | QSIMPLEQ_FIRST(&ms->src_page_requests); |
| 1049 | block = entry->rb; |
| 1050 | *offset = entry->offset; |
| 1051 | *ram_addr_abs = (entry->offset + entry->rb->offset) & |
| 1052 | TARGET_PAGE_MASK; |
| 1053 | |
| 1054 | if (entry->len > TARGET_PAGE_SIZE) { |
| 1055 | entry->len -= TARGET_PAGE_SIZE; |
| 1056 | entry->offset += TARGET_PAGE_SIZE; |
| 1057 | } else { |
| 1058 | memory_region_unref(block->mr); |
| 1059 | QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req); |
| 1060 | g_free(entry); |
| 1061 | } |
| 1062 | } |
| 1063 | qemu_mutex_unlock(&ms->src_page_req_mutex); |
| 1064 | |
| 1065 | return block; |
| 1066 | } |
| 1067 | |
| 1068 | /* |
| 1069 | * Unqueue a page from the queue fed by postcopy page requests; skips pages |
| 1070 | * that are already sent (!dirty) |
| 1071 | * |
| 1072 | * ms: MigrationState in |
| 1073 | * pss: PageSearchStatus structure updated with found block/offset |
| 1074 | * ram_addr_abs: global offset in the dirty/sent bitmaps |
| 1075 | * |
| 1076 | * Returns: true if a queued page is found |
| 1077 | */ |
| 1078 | static bool get_queued_page(MigrationState *ms, PageSearchStatus *pss, |
| 1079 | ram_addr_t *ram_addr_abs) |
| 1080 | { |
| 1081 | RAMBlock *block; |
| 1082 | ram_addr_t offset; |
| 1083 | bool dirty; |
| 1084 | |
| 1085 | do { |
| 1086 | block = unqueue_page(ms, &offset, ram_addr_abs); |
| 1087 | /* |
| 1088 | * We're sending this page, and since it's postcopy nothing else |
| 1089 | * will dirty it, and we must make sure it doesn't get sent again |
| 1090 | * even if this queue request was received after the background |
| 1091 | * search already sent it. |
| 1092 | */ |
| 1093 | if (block) { |
| 1094 | unsigned long *bitmap; |
| 1095 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
| 1096 | dirty = test_bit(*ram_addr_abs >> TARGET_PAGE_BITS, bitmap); |
| 1097 | if (!dirty) { |
| 1098 | trace_get_queued_page_not_dirty( |
| 1099 | block->idstr, (uint64_t)offset, |
| 1100 | (uint64_t)*ram_addr_abs, |
| 1101 | test_bit(*ram_addr_abs >> TARGET_PAGE_BITS, |
| 1102 | atomic_rcu_read(&migration_bitmap_rcu)->unsentmap)); |
| 1103 | } else { |
| 1104 | trace_get_queued_page(block->idstr, |
| 1105 | (uint64_t)offset, |
| 1106 | (uint64_t)*ram_addr_abs); |
| 1107 | } |
| 1108 | } |
| 1109 | |
| 1110 | } while (block && !dirty); |
| 1111 | |
| 1112 | if (block) { |
| 1113 | /* |
| 1114 | * As soon as we start servicing pages out of order, then we have |
| 1115 | * to kill the bulk stage, since the bulk stage assumes |
| 1116 | * in (migration_bitmap_find_and_reset_dirty) that every page is |
| 1117 | * dirty, that's no longer true. |
| 1118 | */ |
| 1119 | ram_bulk_stage = false; |
| 1120 | |
| 1121 | /* |
| 1122 | * We want the background search to continue from the queued page |
| 1123 | * since the guest is likely to want other pages near to the page |
| 1124 | * it just requested. |
| 1125 | */ |
| 1126 | pss->block = block; |
| 1127 | pss->offset = offset; |
| 1128 | } |
| 1129 | |
| 1130 | return !!block; |
| 1131 | } |
| 1132 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1133 | /** |
Dr. David Alan Gilbert | 6c595cd | 2015-11-05 18:11:08 +0000 | [diff] [blame] | 1134 | * flush_page_queue: Flush any remaining pages in the ram request queue |
| 1135 | * it should be empty at the end anyway, but in error cases there may be |
| 1136 | * some left. |
| 1137 | * |
| 1138 | * ms: MigrationState |
| 1139 | */ |
| 1140 | void flush_page_queue(MigrationState *ms) |
| 1141 | { |
| 1142 | struct MigrationSrcPageRequest *mspr, *next_mspr; |
| 1143 | /* This queue generally should be empty - but in the case of a failed |
| 1144 | * migration might have some droppings in. |
| 1145 | */ |
| 1146 | rcu_read_lock(); |
| 1147 | QSIMPLEQ_FOREACH_SAFE(mspr, &ms->src_page_requests, next_req, next_mspr) { |
| 1148 | memory_region_unref(mspr->rb->mr); |
| 1149 | QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req); |
| 1150 | g_free(mspr); |
| 1151 | } |
| 1152 | rcu_read_unlock(); |
| 1153 | } |
| 1154 | |
| 1155 | /** |
| 1156 | * Queue the pages for transmission, e.g. a request from postcopy destination |
| 1157 | * ms: MigrationStatus in which the queue is held |
| 1158 | * rbname: The RAMBlock the request is for - may be NULL (to mean reuse last) |
| 1159 | * start: Offset from the start of the RAMBlock |
| 1160 | * len: Length (in bytes) to send |
| 1161 | * Return: 0 on success |
| 1162 | */ |
| 1163 | int ram_save_queue_pages(MigrationState *ms, const char *rbname, |
| 1164 | ram_addr_t start, ram_addr_t len) |
| 1165 | { |
| 1166 | RAMBlock *ramblock; |
| 1167 | |
| 1168 | rcu_read_lock(); |
| 1169 | if (!rbname) { |
| 1170 | /* Reuse last RAMBlock */ |
| 1171 | ramblock = ms->last_req_rb; |
| 1172 | |
| 1173 | if (!ramblock) { |
| 1174 | /* |
| 1175 | * Shouldn't happen, we can't reuse the last RAMBlock if |
| 1176 | * it's the 1st request. |
| 1177 | */ |
| 1178 | error_report("ram_save_queue_pages no previous block"); |
| 1179 | goto err; |
| 1180 | } |
| 1181 | } else { |
| 1182 | ramblock = qemu_ram_block_by_name(rbname); |
| 1183 | |
| 1184 | if (!ramblock) { |
| 1185 | /* We shouldn't be asked for a non-existent RAMBlock */ |
| 1186 | error_report("ram_save_queue_pages no block '%s'", rbname); |
| 1187 | goto err; |
| 1188 | } |
| 1189 | ms->last_req_rb = ramblock; |
| 1190 | } |
| 1191 | trace_ram_save_queue_pages(ramblock->idstr, start, len); |
| 1192 | if (start+len > ramblock->used_length) { |
Juan Quintela | 9458ad6 | 2015-11-10 17:42:05 +0100 | [diff] [blame] | 1193 | error_report("%s request overrun start=" RAM_ADDR_FMT " len=" |
| 1194 | RAM_ADDR_FMT " blocklen=" RAM_ADDR_FMT, |
Dr. David Alan Gilbert | 6c595cd | 2015-11-05 18:11:08 +0000 | [diff] [blame] | 1195 | __func__, start, len, ramblock->used_length); |
| 1196 | goto err; |
| 1197 | } |
| 1198 | |
| 1199 | struct MigrationSrcPageRequest *new_entry = |
| 1200 | g_malloc0(sizeof(struct MigrationSrcPageRequest)); |
| 1201 | new_entry->rb = ramblock; |
| 1202 | new_entry->offset = start; |
| 1203 | new_entry->len = len; |
| 1204 | |
| 1205 | memory_region_ref(ramblock->mr); |
| 1206 | qemu_mutex_lock(&ms->src_page_req_mutex); |
| 1207 | QSIMPLEQ_INSERT_TAIL(&ms->src_page_requests, new_entry, next_req); |
| 1208 | qemu_mutex_unlock(&ms->src_page_req_mutex); |
| 1209 | rcu_read_unlock(); |
| 1210 | |
| 1211 | return 0; |
| 1212 | |
| 1213 | err: |
| 1214 | rcu_read_unlock(); |
| 1215 | return -1; |
| 1216 | } |
| 1217 | |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1218 | /** |
| 1219 | * ram_save_target_page: Save one target page |
| 1220 | * |
| 1221 | * |
| 1222 | * @f: QEMUFile where to send the data |
| 1223 | * @block: pointer to block that contains the page we want to send |
| 1224 | * @offset: offset inside the block for the page; |
| 1225 | * @last_stage: if we are at the completion stage |
| 1226 | * @bytes_transferred: increase it with the number of transferred bytes |
| 1227 | * @dirty_ram_abs: Address of the start of the dirty page in ram_addr_t space |
| 1228 | * |
| 1229 | * Returns: Number of pages written. |
| 1230 | */ |
| 1231 | static int ram_save_target_page(MigrationState *ms, QEMUFile *f, |
| 1232 | RAMBlock *block, ram_addr_t offset, |
| 1233 | bool last_stage, |
| 1234 | uint64_t *bytes_transferred, |
| 1235 | ram_addr_t dirty_ram_abs) |
| 1236 | { |
| 1237 | int res = 0; |
| 1238 | |
| 1239 | /* Check the pages is dirty and if it is send it */ |
| 1240 | if (migration_bitmap_clear_dirty(dirty_ram_abs)) { |
| 1241 | unsigned long *unsentmap; |
| 1242 | if (compression_switch && migrate_use_compression()) { |
| 1243 | res = ram_save_compressed_page(f, block, offset, |
| 1244 | last_stage, |
| 1245 | bytes_transferred); |
| 1246 | } else { |
| 1247 | res = ram_save_page(f, block, offset, last_stage, |
| 1248 | bytes_transferred); |
| 1249 | } |
| 1250 | |
| 1251 | if (res < 0) { |
| 1252 | return res; |
| 1253 | } |
| 1254 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; |
| 1255 | if (unsentmap) { |
| 1256 | clear_bit(dirty_ram_abs >> TARGET_PAGE_BITS, unsentmap); |
| 1257 | } |
Dr. David Alan Gilbert | 3fd3c4b | 2015-12-10 16:31:46 +0000 | [diff] [blame] | 1258 | /* Only update last_sent_block if a block was actually sent; xbzrle |
| 1259 | * might have decided the page was identical so didn't bother writing |
| 1260 | * to the stream. |
| 1261 | */ |
| 1262 | if (res > 0) { |
| 1263 | last_sent_block = block; |
| 1264 | } |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1265 | } |
| 1266 | |
| 1267 | return res; |
| 1268 | } |
| 1269 | |
| 1270 | /** |
| 1271 | * ram_save_host_page: Starting at *offset send pages upto the end |
| 1272 | * of the current host page. It's valid for the initial |
| 1273 | * offset to point into the middle of a host page |
| 1274 | * in which case the remainder of the hostpage is sent. |
| 1275 | * Only dirty target pages are sent. |
| 1276 | * |
| 1277 | * Returns: Number of pages written. |
| 1278 | * |
| 1279 | * @f: QEMUFile where to send the data |
| 1280 | * @block: pointer to block that contains the page we want to send |
| 1281 | * @offset: offset inside the block for the page; updated to last target page |
| 1282 | * sent |
| 1283 | * @last_stage: if we are at the completion stage |
| 1284 | * @bytes_transferred: increase it with the number of transferred bytes |
| 1285 | * @dirty_ram_abs: Address of the start of the dirty page in ram_addr_t space |
| 1286 | */ |
| 1287 | static int ram_save_host_page(MigrationState *ms, QEMUFile *f, RAMBlock *block, |
| 1288 | ram_addr_t *offset, bool last_stage, |
| 1289 | uint64_t *bytes_transferred, |
| 1290 | ram_addr_t dirty_ram_abs) |
| 1291 | { |
| 1292 | int tmppages, pages = 0; |
| 1293 | do { |
| 1294 | tmppages = ram_save_target_page(ms, f, block, *offset, last_stage, |
| 1295 | bytes_transferred, dirty_ram_abs); |
| 1296 | if (tmppages < 0) { |
| 1297 | return tmppages; |
| 1298 | } |
| 1299 | |
| 1300 | pages += tmppages; |
| 1301 | *offset += TARGET_PAGE_SIZE; |
| 1302 | dirty_ram_abs += TARGET_PAGE_SIZE; |
| 1303 | } while (*offset & (qemu_host_page_size - 1)); |
| 1304 | |
| 1305 | /* The offset we leave with is the last one we looked at */ |
| 1306 | *offset -= TARGET_PAGE_SIZE; |
| 1307 | return pages; |
| 1308 | } |
Dr. David Alan Gilbert | 6c595cd | 2015-11-05 18:11:08 +0000 | [diff] [blame] | 1309 | |
| 1310 | /** |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1311 | * ram_find_and_save_block: Finds a dirty page and sends it to f |
| 1312 | * |
| 1313 | * Called within an RCU critical section. |
| 1314 | * |
| 1315 | * Returns: The number of pages written |
| 1316 | * 0 means no dirty pages |
| 1317 | * |
| 1318 | * @f: QEMUFile where to send the data |
| 1319 | * @last_stage: if we are at the completion stage |
| 1320 | * @bytes_transferred: increase it with the number of transferred bytes |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1321 | * |
| 1322 | * On systems where host-page-size > target-page-size it will send all the |
| 1323 | * pages in a host page that are dirty. |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1324 | */ |
| 1325 | |
| 1326 | static int ram_find_and_save_block(QEMUFile *f, bool last_stage, |
| 1327 | uint64_t *bytes_transferred) |
| 1328 | { |
Dr. David Alan Gilbert | b8fb8cb | 2015-09-23 15:27:10 +0100 | [diff] [blame] | 1329 | PageSearchStatus pss; |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1330 | MigrationState *ms = migrate_get_current(); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1331 | int pages = 0; |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 1332 | bool again, found; |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 1333 | ram_addr_t dirty_ram_abs; /* Address of the start of the dirty page in |
| 1334 | ram_addr_t space */ |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1335 | |
Dr. David Alan Gilbert | b8fb8cb | 2015-09-23 15:27:10 +0100 | [diff] [blame] | 1336 | pss.block = last_seen_block; |
| 1337 | pss.offset = last_offset; |
| 1338 | pss.complete_round = false; |
| 1339 | |
| 1340 | if (!pss.block) { |
| 1341 | pss.block = QLIST_FIRST_RCU(&ram_list.blocks); |
| 1342 | } |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1343 | |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 1344 | do { |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1345 | again = true; |
| 1346 | found = get_queued_page(ms, &pss, &dirty_ram_abs); |
| 1347 | |
| 1348 | if (!found) { |
| 1349 | /* priority queue empty, so just search for something dirty */ |
| 1350 | found = find_dirty_block(f, &pss, &again, &dirty_ram_abs); |
| 1351 | } |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 1352 | |
| 1353 | if (found) { |
Dr. David Alan Gilbert | a82d593 | 2015-11-05 18:11:09 +0000 | [diff] [blame] | 1354 | pages = ram_save_host_page(ms, f, pss.block, &pss.offset, |
| 1355 | last_stage, bytes_transferred, |
| 1356 | dirty_ram_abs); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1357 | } |
Dr. David Alan Gilbert | b9e6092 | 2015-09-23 15:27:11 +0100 | [diff] [blame] | 1358 | } while (!pages && again); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1359 | |
Dr. David Alan Gilbert | b8fb8cb | 2015-09-23 15:27:10 +0100 | [diff] [blame] | 1360 | last_seen_block = pss.block; |
| 1361 | last_offset = pss.offset; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1362 | |
| 1363 | return pages; |
| 1364 | } |
| 1365 | |
| 1366 | void acct_update_position(QEMUFile *f, size_t size, bool zero) |
| 1367 | { |
| 1368 | uint64_t pages = size / TARGET_PAGE_SIZE; |
| 1369 | if (zero) { |
| 1370 | acct_info.dup_pages += pages; |
| 1371 | } else { |
| 1372 | acct_info.norm_pages += pages; |
| 1373 | bytes_transferred += size; |
| 1374 | qemu_update_position(f, size); |
| 1375 | } |
| 1376 | } |
| 1377 | |
| 1378 | static ram_addr_t ram_save_remaining(void) |
| 1379 | { |
| 1380 | return migration_dirty_pages; |
| 1381 | } |
| 1382 | |
| 1383 | uint64_t ram_bytes_remaining(void) |
| 1384 | { |
| 1385 | return ram_save_remaining() * TARGET_PAGE_SIZE; |
| 1386 | } |
| 1387 | |
| 1388 | uint64_t ram_bytes_transferred(void) |
| 1389 | { |
| 1390 | return bytes_transferred; |
| 1391 | } |
| 1392 | |
| 1393 | uint64_t ram_bytes_total(void) |
| 1394 | { |
| 1395 | RAMBlock *block; |
| 1396 | uint64_t total = 0; |
| 1397 | |
| 1398 | rcu_read_lock(); |
| 1399 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) |
| 1400 | total += block->used_length; |
| 1401 | rcu_read_unlock(); |
| 1402 | return total; |
| 1403 | } |
| 1404 | |
| 1405 | void free_xbzrle_decoded_buf(void) |
| 1406 | { |
| 1407 | g_free(xbzrle_decoded_buf); |
| 1408 | xbzrle_decoded_buf = NULL; |
| 1409 | } |
| 1410 | |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1411 | static void migration_bitmap_free(struct BitmapRcu *bmap) |
| 1412 | { |
| 1413 | g_free(bmap->bmap); |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 1414 | g_free(bmap->unsentmap); |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1415 | g_free(bmap); |
| 1416 | } |
| 1417 | |
Liang Li | 6ad2a21 | 2015-11-02 15:37:03 +0800 | [diff] [blame] | 1418 | static void ram_migration_cleanup(void *opaque) |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1419 | { |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 1420 | /* caller have hold iothread lock or is in a bh, so there is |
| 1421 | * no writing race against this migration_bitmap |
| 1422 | */ |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1423 | struct BitmapRcu *bitmap = migration_bitmap_rcu; |
| 1424 | atomic_rcu_set(&migration_bitmap_rcu, NULL); |
Li Zhijian | 2ff6403 | 2015-07-02 20:18:05 +0800 | [diff] [blame] | 1425 | if (bitmap) { |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1426 | memory_global_dirty_log_stop(); |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1427 | call_rcu(bitmap, migration_bitmap_free, rcu); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1428 | } |
| 1429 | |
| 1430 | XBZRLE_cache_lock(); |
| 1431 | if (XBZRLE.cache) { |
| 1432 | cache_fini(XBZRLE.cache); |
| 1433 | g_free(XBZRLE.encoded_buf); |
| 1434 | g_free(XBZRLE.current_buf); |
| 1435 | XBZRLE.cache = NULL; |
| 1436 | XBZRLE.encoded_buf = NULL; |
| 1437 | XBZRLE.current_buf = NULL; |
| 1438 | } |
| 1439 | XBZRLE_cache_unlock(); |
| 1440 | } |
| 1441 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1442 | static void reset_ram_globals(void) |
| 1443 | { |
| 1444 | last_seen_block = NULL; |
| 1445 | last_sent_block = NULL; |
| 1446 | last_offset = 0; |
| 1447 | last_version = ram_list.version; |
| 1448 | ram_bulk_stage = true; |
| 1449 | } |
| 1450 | |
| 1451 | #define MAX_WAIT 50 /* ms, half buffered_file limit */ |
| 1452 | |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 1453 | void migration_bitmap_extend(ram_addr_t old, ram_addr_t new) |
| 1454 | { |
| 1455 | /* called in qemu main thread, so there is |
| 1456 | * no writing race against this migration_bitmap |
| 1457 | */ |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1458 | if (migration_bitmap_rcu) { |
| 1459 | struct BitmapRcu *old_bitmap = migration_bitmap_rcu, *bitmap; |
| 1460 | bitmap = g_new(struct BitmapRcu, 1); |
| 1461 | bitmap->bmap = bitmap_new(new); |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 1462 | |
| 1463 | /* prevent migration_bitmap content from being set bit |
| 1464 | * by migration_bitmap_sync_range() at the same time. |
| 1465 | * it is safe to migration if migration_bitmap is cleared bit |
| 1466 | * at the same time. |
| 1467 | */ |
| 1468 | qemu_mutex_lock(&migration_bitmap_mutex); |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1469 | bitmap_copy(bitmap->bmap, old_bitmap->bmap, old); |
| 1470 | bitmap_set(bitmap->bmap, old, new - old); |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 1471 | |
| 1472 | /* We don't have a way to safely extend the sentmap |
| 1473 | * with RCU; so mark it as missing, entry to postcopy |
| 1474 | * will fail. |
| 1475 | */ |
| 1476 | bitmap->unsentmap = NULL; |
| 1477 | |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1478 | atomic_rcu_set(&migration_bitmap_rcu, bitmap); |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 1479 | qemu_mutex_unlock(&migration_bitmap_mutex); |
| 1480 | migration_dirty_pages += new - old; |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1481 | call_rcu(old_bitmap, migration_bitmap_free, rcu); |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 1482 | } |
| 1483 | } |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1484 | |
Dr. David Alan Gilbert | 4f2e425 | 2015-11-05 18:10:38 +0000 | [diff] [blame] | 1485 | /* |
| 1486 | * 'expected' is the value you expect the bitmap mostly to be full |
| 1487 | * of; it won't bother printing lines that are all this value. |
| 1488 | * If 'todump' is null the migration bitmap is dumped. |
| 1489 | */ |
| 1490 | void ram_debug_dump_bitmap(unsigned long *todump, bool expected) |
| 1491 | { |
| 1492 | int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; |
| 1493 | |
| 1494 | int64_t cur; |
| 1495 | int64_t linelen = 128; |
| 1496 | char linebuf[129]; |
| 1497 | |
| 1498 | if (!todump) { |
| 1499 | todump = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
| 1500 | } |
| 1501 | |
| 1502 | for (cur = 0; cur < ram_pages; cur += linelen) { |
| 1503 | int64_t curb; |
| 1504 | bool found = false; |
| 1505 | /* |
| 1506 | * Last line; catch the case where the line length |
| 1507 | * is longer than remaining ram |
| 1508 | */ |
| 1509 | if (cur + linelen > ram_pages) { |
| 1510 | linelen = ram_pages - cur; |
| 1511 | } |
| 1512 | for (curb = 0; curb < linelen; curb++) { |
| 1513 | bool thisbit = test_bit(cur + curb, todump); |
| 1514 | linebuf[curb] = thisbit ? '1' : '.'; |
| 1515 | found = found || (thisbit != expected); |
| 1516 | } |
| 1517 | if (found) { |
| 1518 | linebuf[curb] = '\0'; |
| 1519 | fprintf(stderr, "0x%08" PRIx64 " : %s\n", cur, linebuf); |
| 1520 | } |
| 1521 | } |
| 1522 | } |
| 1523 | |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 1524 | /* **** functions for postcopy ***** */ |
| 1525 | |
| 1526 | /* |
| 1527 | * Callback from postcopy_each_ram_send_discard for each RAMBlock |
| 1528 | * Note: At this point the 'unsentmap' is the processed bitmap combined |
| 1529 | * with the dirtymap; so a '1' means it's either dirty or unsent. |
| 1530 | * start,length: Indexes into the bitmap for the first bit |
| 1531 | * representing the named block and length in target-pages |
| 1532 | */ |
| 1533 | static int postcopy_send_discard_bm_ram(MigrationState *ms, |
| 1534 | PostcopyDiscardState *pds, |
| 1535 | unsigned long start, |
| 1536 | unsigned long length) |
| 1537 | { |
| 1538 | unsigned long end = start + length; /* one after the end */ |
| 1539 | unsigned long current; |
| 1540 | unsigned long *unsentmap; |
| 1541 | |
| 1542 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; |
| 1543 | for (current = start; current < end; ) { |
| 1544 | unsigned long one = find_next_bit(unsentmap, end, current); |
| 1545 | |
| 1546 | if (one <= end) { |
| 1547 | unsigned long zero = find_next_zero_bit(unsentmap, end, one + 1); |
| 1548 | unsigned long discard_length; |
| 1549 | |
| 1550 | if (zero >= end) { |
| 1551 | discard_length = end - one; |
| 1552 | } else { |
| 1553 | discard_length = zero - one; |
| 1554 | } |
| 1555 | postcopy_discard_send_range(ms, pds, one, discard_length); |
| 1556 | current = one + discard_length; |
| 1557 | } else { |
| 1558 | current = one; |
| 1559 | } |
| 1560 | } |
| 1561 | |
| 1562 | return 0; |
| 1563 | } |
| 1564 | |
| 1565 | /* |
| 1566 | * Utility for the outgoing postcopy code. |
| 1567 | * Calls postcopy_send_discard_bm_ram for each RAMBlock |
| 1568 | * passing it bitmap indexes and name. |
| 1569 | * Returns: 0 on success |
| 1570 | * (qemu_ram_foreach_block ends up passing unscaled lengths |
| 1571 | * which would mean postcopy code would have to deal with target page) |
| 1572 | */ |
| 1573 | static int postcopy_each_ram_send_discard(MigrationState *ms) |
| 1574 | { |
| 1575 | struct RAMBlock *block; |
| 1576 | int ret; |
| 1577 | |
| 1578 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { |
| 1579 | unsigned long first = block->offset >> TARGET_PAGE_BITS; |
| 1580 | PostcopyDiscardState *pds = postcopy_discard_send_init(ms, |
| 1581 | first, |
| 1582 | block->idstr); |
| 1583 | |
| 1584 | /* |
| 1585 | * Postcopy sends chunks of bitmap over the wire, but it |
| 1586 | * just needs indexes at this point, avoids it having |
| 1587 | * target page specific code. |
| 1588 | */ |
| 1589 | ret = postcopy_send_discard_bm_ram(ms, pds, first, |
| 1590 | block->used_length >> TARGET_PAGE_BITS); |
| 1591 | postcopy_discard_send_finish(ms, pds); |
| 1592 | if (ret) { |
| 1593 | return ret; |
| 1594 | } |
| 1595 | } |
| 1596 | |
| 1597 | return 0; |
| 1598 | } |
| 1599 | |
| 1600 | /* |
Dr. David Alan Gilbert | 99e314e | 2015-11-05 18:11:15 +0000 | [diff] [blame] | 1601 | * Helper for postcopy_chunk_hostpages; it's called twice to cleanup |
| 1602 | * the two bitmaps, that are similar, but one is inverted. |
| 1603 | * |
| 1604 | * We search for runs of target-pages that don't start or end on a |
| 1605 | * host page boundary; |
| 1606 | * unsent_pass=true: Cleans up partially unsent host pages by searching |
| 1607 | * the unsentmap |
| 1608 | * unsent_pass=false: Cleans up partially dirty host pages by searching |
| 1609 | * the main migration bitmap |
| 1610 | * |
| 1611 | */ |
| 1612 | static void postcopy_chunk_hostpages_pass(MigrationState *ms, bool unsent_pass, |
| 1613 | RAMBlock *block, |
| 1614 | PostcopyDiscardState *pds) |
| 1615 | { |
| 1616 | unsigned long *bitmap; |
| 1617 | unsigned long *unsentmap; |
| 1618 | unsigned int host_ratio = qemu_host_page_size / TARGET_PAGE_SIZE; |
| 1619 | unsigned long first = block->offset >> TARGET_PAGE_BITS; |
| 1620 | unsigned long len = block->used_length >> TARGET_PAGE_BITS; |
| 1621 | unsigned long last = first + (len - 1); |
| 1622 | unsigned long run_start; |
| 1623 | |
| 1624 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
| 1625 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; |
| 1626 | |
| 1627 | if (unsent_pass) { |
| 1628 | /* Find a sent page */ |
| 1629 | run_start = find_next_zero_bit(unsentmap, last + 1, first); |
| 1630 | } else { |
| 1631 | /* Find a dirty page */ |
| 1632 | run_start = find_next_bit(bitmap, last + 1, first); |
| 1633 | } |
| 1634 | |
| 1635 | while (run_start <= last) { |
| 1636 | bool do_fixup = false; |
| 1637 | unsigned long fixup_start_addr; |
| 1638 | unsigned long host_offset; |
| 1639 | |
| 1640 | /* |
| 1641 | * If the start of this run of pages is in the middle of a host |
| 1642 | * page, then we need to fixup this host page. |
| 1643 | */ |
| 1644 | host_offset = run_start % host_ratio; |
| 1645 | if (host_offset) { |
| 1646 | do_fixup = true; |
| 1647 | run_start -= host_offset; |
| 1648 | fixup_start_addr = run_start; |
| 1649 | /* For the next pass */ |
| 1650 | run_start = run_start + host_ratio; |
| 1651 | } else { |
| 1652 | /* Find the end of this run */ |
| 1653 | unsigned long run_end; |
| 1654 | if (unsent_pass) { |
| 1655 | run_end = find_next_bit(unsentmap, last + 1, run_start + 1); |
| 1656 | } else { |
| 1657 | run_end = find_next_zero_bit(bitmap, last + 1, run_start + 1); |
| 1658 | } |
| 1659 | /* |
| 1660 | * If the end isn't at the start of a host page, then the |
| 1661 | * run doesn't finish at the end of a host page |
| 1662 | * and we need to discard. |
| 1663 | */ |
| 1664 | host_offset = run_end % host_ratio; |
| 1665 | if (host_offset) { |
| 1666 | do_fixup = true; |
| 1667 | fixup_start_addr = run_end - host_offset; |
| 1668 | /* |
| 1669 | * This host page has gone, the next loop iteration starts |
| 1670 | * from after the fixup |
| 1671 | */ |
| 1672 | run_start = fixup_start_addr + host_ratio; |
| 1673 | } else { |
| 1674 | /* |
| 1675 | * No discards on this iteration, next loop starts from |
| 1676 | * next sent/dirty page |
| 1677 | */ |
| 1678 | run_start = run_end + 1; |
| 1679 | } |
| 1680 | } |
| 1681 | |
| 1682 | if (do_fixup) { |
| 1683 | unsigned long page; |
| 1684 | |
| 1685 | /* Tell the destination to discard this page */ |
| 1686 | if (unsent_pass || !test_bit(fixup_start_addr, unsentmap)) { |
| 1687 | /* For the unsent_pass we: |
| 1688 | * discard partially sent pages |
| 1689 | * For the !unsent_pass (dirty) we: |
| 1690 | * discard partially dirty pages that were sent |
| 1691 | * (any partially sent pages were already discarded |
| 1692 | * by the previous unsent_pass) |
| 1693 | */ |
| 1694 | postcopy_discard_send_range(ms, pds, fixup_start_addr, |
| 1695 | host_ratio); |
| 1696 | } |
| 1697 | |
| 1698 | /* Clean up the bitmap */ |
| 1699 | for (page = fixup_start_addr; |
| 1700 | page < fixup_start_addr + host_ratio; page++) { |
| 1701 | /* All pages in this host page are now not sent */ |
| 1702 | set_bit(page, unsentmap); |
| 1703 | |
| 1704 | /* |
| 1705 | * Remark them as dirty, updating the count for any pages |
| 1706 | * that weren't previously dirty. |
| 1707 | */ |
| 1708 | migration_dirty_pages += !test_and_set_bit(page, bitmap); |
| 1709 | } |
| 1710 | } |
| 1711 | |
| 1712 | if (unsent_pass) { |
| 1713 | /* Find the next sent page for the next iteration */ |
| 1714 | run_start = find_next_zero_bit(unsentmap, last + 1, |
| 1715 | run_start); |
| 1716 | } else { |
| 1717 | /* Find the next dirty page for the next iteration */ |
| 1718 | run_start = find_next_bit(bitmap, last + 1, run_start); |
| 1719 | } |
| 1720 | } |
| 1721 | } |
| 1722 | |
| 1723 | /* |
| 1724 | * Utility for the outgoing postcopy code. |
| 1725 | * |
| 1726 | * Discard any partially sent host-page size chunks, mark any partially |
| 1727 | * dirty host-page size chunks as all dirty. |
| 1728 | * |
| 1729 | * Returns: 0 on success |
| 1730 | */ |
| 1731 | static int postcopy_chunk_hostpages(MigrationState *ms) |
| 1732 | { |
| 1733 | struct RAMBlock *block; |
| 1734 | |
| 1735 | if (qemu_host_page_size == TARGET_PAGE_SIZE) { |
| 1736 | /* Easy case - TPS==HPS - nothing to be done */ |
| 1737 | return 0; |
| 1738 | } |
| 1739 | |
| 1740 | /* Easiest way to make sure we don't resume in the middle of a host-page */ |
| 1741 | last_seen_block = NULL; |
| 1742 | last_sent_block = NULL; |
| 1743 | last_offset = 0; |
| 1744 | |
| 1745 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { |
| 1746 | unsigned long first = block->offset >> TARGET_PAGE_BITS; |
| 1747 | |
| 1748 | PostcopyDiscardState *pds = |
| 1749 | postcopy_discard_send_init(ms, first, block->idstr); |
| 1750 | |
| 1751 | /* First pass: Discard all partially sent host pages */ |
| 1752 | postcopy_chunk_hostpages_pass(ms, true, block, pds); |
| 1753 | /* |
| 1754 | * Second pass: Ensure that all partially dirty host pages are made |
| 1755 | * fully dirty. |
| 1756 | */ |
| 1757 | postcopy_chunk_hostpages_pass(ms, false, block, pds); |
| 1758 | |
| 1759 | postcopy_discard_send_finish(ms, pds); |
| 1760 | } /* ram_list loop */ |
| 1761 | |
| 1762 | return 0; |
| 1763 | } |
| 1764 | |
| 1765 | /* |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 1766 | * Transmit the set of pages to be discarded after precopy to the target |
| 1767 | * these are pages that: |
| 1768 | * a) Have been previously transmitted but are now dirty again |
| 1769 | * b) Pages that have never been transmitted, this ensures that |
| 1770 | * any pages on the destination that have been mapped by background |
| 1771 | * tasks get discarded (transparent huge pages is the specific concern) |
| 1772 | * Hopefully this is pretty sparse |
| 1773 | */ |
| 1774 | int ram_postcopy_send_discard_bitmap(MigrationState *ms) |
| 1775 | { |
| 1776 | int ret; |
| 1777 | unsigned long *bitmap, *unsentmap; |
| 1778 | |
| 1779 | rcu_read_lock(); |
| 1780 | |
| 1781 | /* This should be our last sync, the src is now paused */ |
| 1782 | migration_bitmap_sync(); |
| 1783 | |
| 1784 | unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap; |
| 1785 | if (!unsentmap) { |
| 1786 | /* We don't have a safe way to resize the sentmap, so |
| 1787 | * if the bitmap was resized it will be NULL at this |
| 1788 | * point. |
| 1789 | */ |
| 1790 | error_report("migration ram resized during precopy phase"); |
| 1791 | rcu_read_unlock(); |
| 1792 | return -EINVAL; |
| 1793 | } |
| 1794 | |
Dr. David Alan Gilbert | 99e314e | 2015-11-05 18:11:15 +0000 | [diff] [blame] | 1795 | /* Deal with TPS != HPS */ |
| 1796 | ret = postcopy_chunk_hostpages(ms); |
| 1797 | if (ret) { |
| 1798 | rcu_read_unlock(); |
| 1799 | return ret; |
| 1800 | } |
| 1801 | |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 1802 | /* |
| 1803 | * Update the unsentmap to be unsentmap = unsentmap | dirty |
| 1804 | */ |
| 1805 | bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap; |
| 1806 | bitmap_or(unsentmap, unsentmap, bitmap, |
| 1807 | last_ram_offset() >> TARGET_PAGE_BITS); |
| 1808 | |
| 1809 | |
| 1810 | trace_ram_postcopy_send_discard_bitmap(); |
| 1811 | #ifdef DEBUG_POSTCOPY |
| 1812 | ram_debug_dump_bitmap(unsentmap, true); |
| 1813 | #endif |
| 1814 | |
| 1815 | ret = postcopy_each_ram_send_discard(ms); |
| 1816 | rcu_read_unlock(); |
| 1817 | |
| 1818 | return ret; |
| 1819 | } |
| 1820 | |
| 1821 | /* |
| 1822 | * At the start of the postcopy phase of migration, any now-dirty |
| 1823 | * precopied pages are discarded. |
| 1824 | * |
| 1825 | * start, length describe a byte address range within the RAMBlock |
| 1826 | * |
| 1827 | * Returns 0 on success. |
| 1828 | */ |
| 1829 | int ram_discard_range(MigrationIncomingState *mis, |
| 1830 | const char *block_name, |
| 1831 | uint64_t start, size_t length) |
| 1832 | { |
| 1833 | int ret = -1; |
| 1834 | |
| 1835 | rcu_read_lock(); |
| 1836 | RAMBlock *rb = qemu_ram_block_by_name(block_name); |
| 1837 | |
| 1838 | if (!rb) { |
| 1839 | error_report("ram_discard_range: Failed to find block '%s'", |
| 1840 | block_name); |
| 1841 | goto err; |
| 1842 | } |
| 1843 | |
| 1844 | uint8_t *host_startaddr = rb->host + start; |
| 1845 | |
| 1846 | if ((uintptr_t)host_startaddr & (qemu_host_page_size - 1)) { |
| 1847 | error_report("ram_discard_range: Unaligned start address: %p", |
| 1848 | host_startaddr); |
| 1849 | goto err; |
| 1850 | } |
| 1851 | |
| 1852 | if ((start + length) <= rb->used_length) { |
| 1853 | uint8_t *host_endaddr = host_startaddr + length; |
| 1854 | if ((uintptr_t)host_endaddr & (qemu_host_page_size - 1)) { |
| 1855 | error_report("ram_discard_range: Unaligned end address: %p", |
| 1856 | host_endaddr); |
| 1857 | goto err; |
| 1858 | } |
| 1859 | ret = postcopy_ram_discard_range(mis, host_startaddr, length); |
| 1860 | } else { |
| 1861 | error_report("ram_discard_range: Overrun block '%s' (%" PRIu64 |
Juan Quintela | 9458ad6 | 2015-11-10 17:42:05 +0100 | [diff] [blame] | 1862 | "/%zx/" RAM_ADDR_FMT")", |
Dr. David Alan Gilbert | e0b266f | 2015-11-05 18:11:02 +0000 | [diff] [blame] | 1863 | block_name, start, length, rb->used_length); |
| 1864 | } |
| 1865 | |
| 1866 | err: |
| 1867 | rcu_read_unlock(); |
| 1868 | |
| 1869 | return ret; |
| 1870 | } |
| 1871 | |
| 1872 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1873 | /* Each of ram_save_setup, ram_save_iterate and ram_save_complete has |
| 1874 | * long-running RCU critical section. When rcu-reclaims in the code |
| 1875 | * start to become numerous it will be necessary to reduce the |
| 1876 | * granularity of these critical sections. |
| 1877 | */ |
| 1878 | |
| 1879 | static int ram_save_setup(QEMUFile *f, void *opaque) |
| 1880 | { |
| 1881 | RAMBlock *block; |
| 1882 | int64_t ram_bitmap_pages; /* Size of bitmap in pages, including gaps */ |
| 1883 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1884 | dirty_rate_high_cnt = 0; |
| 1885 | bitmap_sync_count = 0; |
| 1886 | migration_bitmap_sync_init(); |
Li Zhijian | dd63169 | 2015-07-02 20:18:06 +0800 | [diff] [blame] | 1887 | qemu_mutex_init(&migration_bitmap_mutex); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1888 | |
| 1889 | if (migrate_use_xbzrle()) { |
| 1890 | XBZRLE_cache_lock(); |
| 1891 | XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / |
| 1892 | TARGET_PAGE_SIZE, |
| 1893 | TARGET_PAGE_SIZE); |
| 1894 | if (!XBZRLE.cache) { |
| 1895 | XBZRLE_cache_unlock(); |
| 1896 | error_report("Error creating cache"); |
| 1897 | return -1; |
| 1898 | } |
| 1899 | XBZRLE_cache_unlock(); |
| 1900 | |
| 1901 | /* We prefer not to abort if there is no memory */ |
| 1902 | XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); |
| 1903 | if (!XBZRLE.encoded_buf) { |
| 1904 | error_report("Error allocating encoded_buf"); |
| 1905 | return -1; |
| 1906 | } |
| 1907 | |
| 1908 | XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); |
| 1909 | if (!XBZRLE.current_buf) { |
| 1910 | error_report("Error allocating current_buf"); |
| 1911 | g_free(XBZRLE.encoded_buf); |
| 1912 | XBZRLE.encoded_buf = NULL; |
| 1913 | return -1; |
| 1914 | } |
| 1915 | |
| 1916 | acct_clear(); |
| 1917 | } |
| 1918 | |
| 1919 | /* iothread lock needed for ram_list.dirty_memory[] */ |
| 1920 | qemu_mutex_lock_iothread(); |
| 1921 | qemu_mutex_lock_ramlist(); |
| 1922 | rcu_read_lock(); |
| 1923 | bytes_transferred = 0; |
| 1924 | reset_ram_globals(); |
| 1925 | |
| 1926 | ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS; |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 1927 | migration_bitmap_rcu = g_new0(struct BitmapRcu, 1); |
Denis V. Lunev | 60be634 | 2015-09-28 14:41:58 +0300 | [diff] [blame] | 1928 | migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages); |
| 1929 | bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1930 | |
Dr. David Alan Gilbert | f3f491f | 2015-11-05 18:11:01 +0000 | [diff] [blame] | 1931 | if (migrate_postcopy_ram()) { |
| 1932 | migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages); |
| 1933 | bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages); |
| 1934 | } |
| 1935 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1936 | /* |
| 1937 | * Count the total number of pages used by ram blocks not including any |
| 1938 | * gaps due to alignment or unplugs. |
| 1939 | */ |
| 1940 | migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS; |
| 1941 | |
| 1942 | memory_global_dirty_log_start(); |
| 1943 | migration_bitmap_sync(); |
| 1944 | qemu_mutex_unlock_ramlist(); |
| 1945 | qemu_mutex_unlock_iothread(); |
| 1946 | |
| 1947 | qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE); |
| 1948 | |
| 1949 | QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { |
| 1950 | qemu_put_byte(f, strlen(block->idstr)); |
| 1951 | qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); |
| 1952 | qemu_put_be64(f, block->used_length); |
| 1953 | } |
| 1954 | |
| 1955 | rcu_read_unlock(); |
| 1956 | |
| 1957 | ram_control_before_iterate(f, RAM_CONTROL_SETUP); |
| 1958 | ram_control_after_iterate(f, RAM_CONTROL_SETUP); |
| 1959 | |
| 1960 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
| 1961 | |
| 1962 | return 0; |
| 1963 | } |
| 1964 | |
| 1965 | static int ram_save_iterate(QEMUFile *f, void *opaque) |
| 1966 | { |
| 1967 | int ret; |
| 1968 | int i; |
| 1969 | int64_t t0; |
| 1970 | int pages_sent = 0; |
| 1971 | |
| 1972 | rcu_read_lock(); |
| 1973 | if (ram_list.version != last_version) { |
| 1974 | reset_ram_globals(); |
| 1975 | } |
| 1976 | |
| 1977 | /* Read version before ram_list.blocks */ |
| 1978 | smp_rmb(); |
| 1979 | |
| 1980 | ram_control_before_iterate(f, RAM_CONTROL_ROUND); |
| 1981 | |
| 1982 | t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); |
| 1983 | i = 0; |
| 1984 | while ((ret = qemu_file_rate_limit(f)) == 0) { |
| 1985 | int pages; |
| 1986 | |
| 1987 | pages = ram_find_and_save_block(f, false, &bytes_transferred); |
| 1988 | /* no more pages to sent */ |
| 1989 | if (pages == 0) { |
| 1990 | break; |
| 1991 | } |
| 1992 | pages_sent += pages; |
| 1993 | acct_info.iterations++; |
Jason J. Herne | 070afca | 2015-09-08 13:12:35 -0400 | [diff] [blame] | 1994 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 1995 | /* we want to check in the 1st loop, just in case it was the 1st time |
| 1996 | and we had to sync the dirty bitmap. |
| 1997 | qemu_get_clock_ns() is a bit expensive, so we only check each some |
| 1998 | iterations |
| 1999 | */ |
| 2000 | if ((i & 63) == 0) { |
| 2001 | uint64_t t1 = (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - t0) / 1000000; |
| 2002 | if (t1 > MAX_WAIT) { |
| 2003 | DPRINTF("big wait: %" PRIu64 " milliseconds, %d iterations\n", |
| 2004 | t1, i); |
| 2005 | break; |
| 2006 | } |
| 2007 | } |
| 2008 | i++; |
| 2009 | } |
| 2010 | flush_compressed_data(f); |
| 2011 | rcu_read_unlock(); |
| 2012 | |
| 2013 | /* |
| 2014 | * Must occur before EOS (or any QEMUFile operation) |
| 2015 | * because of RDMA protocol. |
| 2016 | */ |
| 2017 | ram_control_after_iterate(f, RAM_CONTROL_ROUND); |
| 2018 | |
| 2019 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
| 2020 | bytes_transferred += 8; |
| 2021 | |
| 2022 | ret = qemu_file_get_error(f); |
| 2023 | if (ret < 0) { |
| 2024 | return ret; |
| 2025 | } |
| 2026 | |
| 2027 | return pages_sent; |
| 2028 | } |
| 2029 | |
| 2030 | /* Called with iothread lock */ |
| 2031 | static int ram_save_complete(QEMUFile *f, void *opaque) |
| 2032 | { |
| 2033 | rcu_read_lock(); |
| 2034 | |
Dr. David Alan Gilbert | 663e6c1 | 2015-11-05 18:11:13 +0000 | [diff] [blame] | 2035 | if (!migration_in_postcopy(migrate_get_current())) { |
| 2036 | migration_bitmap_sync(); |
| 2037 | } |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2038 | |
| 2039 | ram_control_before_iterate(f, RAM_CONTROL_FINISH); |
| 2040 | |
| 2041 | /* try transferring iterative blocks of memory */ |
| 2042 | |
| 2043 | /* flush all remaining blocks regardless of rate limiting */ |
| 2044 | while (true) { |
| 2045 | int pages; |
| 2046 | |
| 2047 | pages = ram_find_and_save_block(f, true, &bytes_transferred); |
| 2048 | /* no more blocks to sent */ |
| 2049 | if (pages == 0) { |
| 2050 | break; |
| 2051 | } |
| 2052 | } |
| 2053 | |
| 2054 | flush_compressed_data(f); |
| 2055 | ram_control_after_iterate(f, RAM_CONTROL_FINISH); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2056 | |
| 2057 | rcu_read_unlock(); |
Paolo Bonzini | d09a6fd | 2015-07-09 08:47:58 +0200 | [diff] [blame] | 2058 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2059 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
| 2060 | |
| 2061 | return 0; |
| 2062 | } |
| 2063 | |
Dr. David Alan Gilbert | c31b098 | 2015-11-05 18:10:54 +0000 | [diff] [blame] | 2064 | static void ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size, |
| 2065 | uint64_t *non_postcopiable_pending, |
| 2066 | uint64_t *postcopiable_pending) |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2067 | { |
| 2068 | uint64_t remaining_size; |
| 2069 | |
| 2070 | remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; |
| 2071 | |
Dr. David Alan Gilbert | 663e6c1 | 2015-11-05 18:11:13 +0000 | [diff] [blame] | 2072 | if (!migration_in_postcopy(migrate_get_current()) && |
| 2073 | remaining_size < max_size) { |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2074 | qemu_mutex_lock_iothread(); |
| 2075 | rcu_read_lock(); |
| 2076 | migration_bitmap_sync(); |
| 2077 | rcu_read_unlock(); |
| 2078 | qemu_mutex_unlock_iothread(); |
| 2079 | remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; |
| 2080 | } |
Dr. David Alan Gilbert | c31b098 | 2015-11-05 18:10:54 +0000 | [diff] [blame] | 2081 | |
| 2082 | /* We can do postcopy, and all the data is postcopiable */ |
| 2083 | *postcopiable_pending += remaining_size; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2084 | } |
| 2085 | |
| 2086 | static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) |
| 2087 | { |
| 2088 | unsigned int xh_len; |
| 2089 | int xh_flags; |
Dr. David Alan Gilbert | 063e760 | 2015-12-16 11:47:37 +0000 | [diff] [blame] | 2090 | uint8_t *loaded_data; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2091 | |
| 2092 | if (!xbzrle_decoded_buf) { |
| 2093 | xbzrle_decoded_buf = g_malloc(TARGET_PAGE_SIZE); |
| 2094 | } |
Dr. David Alan Gilbert | 063e760 | 2015-12-16 11:47:37 +0000 | [diff] [blame] | 2095 | loaded_data = xbzrle_decoded_buf; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2096 | |
| 2097 | /* extract RLE header */ |
| 2098 | xh_flags = qemu_get_byte(f); |
| 2099 | xh_len = qemu_get_be16(f); |
| 2100 | |
| 2101 | if (xh_flags != ENCODING_FLAG_XBZRLE) { |
| 2102 | error_report("Failed to load XBZRLE page - wrong compression!"); |
| 2103 | return -1; |
| 2104 | } |
| 2105 | |
| 2106 | if (xh_len > TARGET_PAGE_SIZE) { |
| 2107 | error_report("Failed to load XBZRLE page - len overflow!"); |
| 2108 | return -1; |
| 2109 | } |
| 2110 | /* load data and decode */ |
Dr. David Alan Gilbert | 063e760 | 2015-12-16 11:47:37 +0000 | [diff] [blame] | 2111 | qemu_get_buffer_in_place(f, &loaded_data, xh_len); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2112 | |
| 2113 | /* decode RLE */ |
Dr. David Alan Gilbert | 063e760 | 2015-12-16 11:47:37 +0000 | [diff] [blame] | 2114 | if (xbzrle_decode_buffer(loaded_data, xh_len, host, |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2115 | TARGET_PAGE_SIZE) == -1) { |
| 2116 | error_report("Failed to load XBZRLE page - decode error!"); |
| 2117 | return -1; |
| 2118 | } |
| 2119 | |
| 2120 | return 0; |
| 2121 | } |
| 2122 | |
| 2123 | /* Must be called from within a rcu critical section. |
| 2124 | * Returns a pointer from within the RCU-protected ram_list. |
| 2125 | */ |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2126 | /* |
| 2127 | * Read a RAMBlock ID from the stream f, find the host address of the |
| 2128 | * start of that block and add on 'offset' |
| 2129 | * |
| 2130 | * f: Stream to read from |
| 2131 | * offset: Offset within the block |
| 2132 | * flags: Page flags (mostly to see if it's a continuation of previous block) |
| 2133 | */ |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2134 | static inline void *host_from_stream_offset(QEMUFile *f, |
| 2135 | ram_addr_t offset, |
| 2136 | int flags) |
| 2137 | { |
| 2138 | static RAMBlock *block = NULL; |
| 2139 | char id[256]; |
| 2140 | uint8_t len; |
| 2141 | |
| 2142 | if (flags & RAM_SAVE_FLAG_CONTINUE) { |
| 2143 | if (!block || block->max_length <= offset) { |
| 2144 | error_report("Ack, bad migration stream!"); |
| 2145 | return NULL; |
| 2146 | } |
| 2147 | |
Dr. David Alan Gilbert | 2f68e39 | 2015-08-13 11:51:30 +0100 | [diff] [blame] | 2148 | return block->host + offset; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2149 | } |
| 2150 | |
| 2151 | len = qemu_get_byte(f); |
| 2152 | qemu_get_buffer(f, (uint8_t *)id, len); |
| 2153 | id[len] = 0; |
| 2154 | |
Dr. David Alan Gilbert | e3dd749 | 2015-11-05 18:10:33 +0000 | [diff] [blame] | 2155 | block = qemu_ram_block_by_name(id); |
| 2156 | if (block && block->max_length > offset) { |
| 2157 | return block->host + offset; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2158 | } |
| 2159 | |
Dr. David Alan Gilbert | e3dd749 | 2015-11-05 18:10:33 +0000 | [diff] [blame] | 2160 | error_report("Can't find block %s", id); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2161 | return NULL; |
| 2162 | } |
| 2163 | |
| 2164 | /* |
| 2165 | * If a page (or a whole RDMA chunk) has been |
| 2166 | * determined to be zero, then zap it. |
| 2167 | */ |
| 2168 | void ram_handle_compressed(void *host, uint8_t ch, uint64_t size) |
| 2169 | { |
| 2170 | if (ch != 0 || !is_zero_range(host, size)) { |
| 2171 | memset(host, ch, size); |
| 2172 | } |
| 2173 | } |
| 2174 | |
| 2175 | static void *do_data_decompress(void *opaque) |
| 2176 | { |
| 2177 | DecompressParam *param = opaque; |
| 2178 | unsigned long pagesize; |
| 2179 | |
| 2180 | while (!quit_decomp_thread) { |
| 2181 | qemu_mutex_lock(¶m->mutex); |
| 2182 | while (!param->start && !quit_decomp_thread) { |
| 2183 | qemu_cond_wait(¶m->cond, ¶m->mutex); |
| 2184 | pagesize = TARGET_PAGE_SIZE; |
| 2185 | if (!quit_decomp_thread) { |
| 2186 | /* uncompress() will return failed in some case, especially |
| 2187 | * when the page is dirted when doing the compression, it's |
| 2188 | * not a problem because the dirty page will be retransferred |
| 2189 | * and uncompress() won't break the data in other pages. |
| 2190 | */ |
| 2191 | uncompress((Bytef *)param->des, &pagesize, |
| 2192 | (const Bytef *)param->compbuf, param->len); |
| 2193 | } |
| 2194 | param->start = false; |
| 2195 | } |
| 2196 | qemu_mutex_unlock(¶m->mutex); |
| 2197 | } |
| 2198 | |
| 2199 | return NULL; |
| 2200 | } |
| 2201 | |
| 2202 | void migrate_decompress_threads_create(void) |
| 2203 | { |
| 2204 | int i, thread_count; |
| 2205 | |
| 2206 | thread_count = migrate_decompress_threads(); |
| 2207 | decompress_threads = g_new0(QemuThread, thread_count); |
| 2208 | decomp_param = g_new0(DecompressParam, thread_count); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2209 | quit_decomp_thread = false; |
| 2210 | for (i = 0; i < thread_count; i++) { |
| 2211 | qemu_mutex_init(&decomp_param[i].mutex); |
| 2212 | qemu_cond_init(&decomp_param[i].cond); |
| 2213 | decomp_param[i].compbuf = g_malloc0(compressBound(TARGET_PAGE_SIZE)); |
| 2214 | qemu_thread_create(decompress_threads + i, "decompress", |
| 2215 | do_data_decompress, decomp_param + i, |
| 2216 | QEMU_THREAD_JOINABLE); |
| 2217 | } |
| 2218 | } |
| 2219 | |
| 2220 | void migrate_decompress_threads_join(void) |
| 2221 | { |
| 2222 | int i, thread_count; |
| 2223 | |
| 2224 | quit_decomp_thread = true; |
| 2225 | thread_count = migrate_decompress_threads(); |
| 2226 | for (i = 0; i < thread_count; i++) { |
| 2227 | qemu_mutex_lock(&decomp_param[i].mutex); |
| 2228 | qemu_cond_signal(&decomp_param[i].cond); |
| 2229 | qemu_mutex_unlock(&decomp_param[i].mutex); |
| 2230 | } |
| 2231 | for (i = 0; i < thread_count; i++) { |
| 2232 | qemu_thread_join(decompress_threads + i); |
| 2233 | qemu_mutex_destroy(&decomp_param[i].mutex); |
| 2234 | qemu_cond_destroy(&decomp_param[i].cond); |
| 2235 | g_free(decomp_param[i].compbuf); |
| 2236 | } |
| 2237 | g_free(decompress_threads); |
| 2238 | g_free(decomp_param); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2239 | decompress_threads = NULL; |
| 2240 | decomp_param = NULL; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2241 | } |
| 2242 | |
Dr. David Alan Gilbert | c1bc662 | 2015-12-16 11:47:38 +0000 | [diff] [blame] | 2243 | static void decompress_data_with_multi_threads(QEMUFile *f, |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2244 | void *host, int len) |
| 2245 | { |
| 2246 | int idx, thread_count; |
| 2247 | |
| 2248 | thread_count = migrate_decompress_threads(); |
| 2249 | while (true) { |
| 2250 | for (idx = 0; idx < thread_count; idx++) { |
| 2251 | if (!decomp_param[idx].start) { |
Dr. David Alan Gilbert | c1bc662 | 2015-12-16 11:47:38 +0000 | [diff] [blame] | 2252 | qemu_get_buffer(f, decomp_param[idx].compbuf, len); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2253 | decomp_param[idx].des = host; |
| 2254 | decomp_param[idx].len = len; |
| 2255 | start_decompression(&decomp_param[idx]); |
| 2256 | break; |
| 2257 | } |
| 2258 | } |
| 2259 | if (idx < thread_count) { |
| 2260 | break; |
| 2261 | } |
| 2262 | } |
| 2263 | } |
| 2264 | |
Dr. David Alan Gilbert | 1caddf8 | 2015-11-05 18:11:03 +0000 | [diff] [blame] | 2265 | /* |
| 2266 | * Allocate data structures etc needed by incoming migration with postcopy-ram |
| 2267 | * postcopy-ram's similarly names postcopy_ram_incoming_init does the work |
| 2268 | */ |
| 2269 | int ram_postcopy_incoming_init(MigrationIncomingState *mis) |
| 2270 | { |
| 2271 | size_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; |
| 2272 | |
| 2273 | return postcopy_ram_incoming_init(mis, ram_pages); |
| 2274 | } |
| 2275 | |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2276 | /* |
| 2277 | * Called in postcopy mode by ram_load(). |
| 2278 | * rcu_read_lock is taken prior to this being called. |
| 2279 | */ |
| 2280 | static int ram_load_postcopy(QEMUFile *f) |
| 2281 | { |
| 2282 | int flags = 0, ret = 0; |
| 2283 | bool place_needed = false; |
| 2284 | bool matching_page_sizes = qemu_host_page_size == TARGET_PAGE_SIZE; |
| 2285 | MigrationIncomingState *mis = migration_incoming_get_current(); |
| 2286 | /* Temporary page that is later 'placed' */ |
| 2287 | void *postcopy_host_page = postcopy_get_tmp_page(mis); |
Dr. David Alan Gilbert | c53b7dd | 2015-11-05 18:11:12 +0000 | [diff] [blame] | 2288 | void *last_host = NULL; |
Dr. David Alan Gilbert | a3b6ff6 | 2015-11-11 14:02:28 +0000 | [diff] [blame] | 2289 | bool all_zero = false; |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2290 | |
| 2291 | while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { |
| 2292 | ram_addr_t addr; |
| 2293 | void *host = NULL; |
| 2294 | void *page_buffer = NULL; |
| 2295 | void *place_source = NULL; |
| 2296 | uint8_t ch; |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2297 | |
| 2298 | addr = qemu_get_be64(f); |
| 2299 | flags = addr & ~TARGET_PAGE_MASK; |
| 2300 | addr &= TARGET_PAGE_MASK; |
| 2301 | |
| 2302 | trace_ram_load_postcopy_loop((uint64_t)addr, flags); |
| 2303 | place_needed = false; |
| 2304 | if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE)) { |
| 2305 | host = host_from_stream_offset(f, addr, flags); |
| 2306 | if (!host) { |
| 2307 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); |
| 2308 | ret = -EINVAL; |
| 2309 | break; |
| 2310 | } |
| 2311 | page_buffer = host; |
| 2312 | /* |
| 2313 | * Postcopy requires that we place whole host pages atomically. |
| 2314 | * To make it atomic, the data is read into a temporary page |
| 2315 | * that's moved into place later. |
| 2316 | * The migration protocol uses, possibly smaller, target-pages |
| 2317 | * however the source ensures it always sends all the components |
| 2318 | * of a host page in order. |
| 2319 | */ |
| 2320 | page_buffer = postcopy_host_page + |
| 2321 | ((uintptr_t)host & ~qemu_host_page_mask); |
| 2322 | /* If all TP are zero then we can optimise the place */ |
| 2323 | if (!((uintptr_t)host & ~qemu_host_page_mask)) { |
| 2324 | all_zero = true; |
Dr. David Alan Gilbert | c53b7dd | 2015-11-05 18:11:12 +0000 | [diff] [blame] | 2325 | } else { |
| 2326 | /* not the 1st TP within the HP */ |
| 2327 | if (host != (last_host + TARGET_PAGE_SIZE)) { |
Markus Armbruster | 9af9e0f | 2015-12-18 16:35:19 +0100 | [diff] [blame] | 2328 | error_report("Non-sequential target page %p/%p", |
Dr. David Alan Gilbert | c53b7dd | 2015-11-05 18:11:12 +0000 | [diff] [blame] | 2329 | host, last_host); |
| 2330 | ret = -EINVAL; |
| 2331 | break; |
| 2332 | } |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2333 | } |
| 2334 | |
Dr. David Alan Gilbert | c53b7dd | 2015-11-05 18:11:12 +0000 | [diff] [blame] | 2335 | |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2336 | /* |
| 2337 | * If it's the last part of a host page then we place the host |
| 2338 | * page |
| 2339 | */ |
| 2340 | place_needed = (((uintptr_t)host + TARGET_PAGE_SIZE) & |
| 2341 | ~qemu_host_page_mask) == 0; |
| 2342 | place_source = postcopy_host_page; |
| 2343 | } |
Dr. David Alan Gilbert | c53b7dd | 2015-11-05 18:11:12 +0000 | [diff] [blame] | 2344 | last_host = host; |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2345 | |
| 2346 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { |
| 2347 | case RAM_SAVE_FLAG_COMPRESS: |
| 2348 | ch = qemu_get_byte(f); |
| 2349 | memset(page_buffer, ch, TARGET_PAGE_SIZE); |
| 2350 | if (ch) { |
| 2351 | all_zero = false; |
| 2352 | } |
| 2353 | break; |
| 2354 | |
| 2355 | case RAM_SAVE_FLAG_PAGE: |
| 2356 | all_zero = false; |
| 2357 | if (!place_needed || !matching_page_sizes) { |
| 2358 | qemu_get_buffer(f, page_buffer, TARGET_PAGE_SIZE); |
| 2359 | } else { |
| 2360 | /* Avoids the qemu_file copy during postcopy, which is |
| 2361 | * going to do a copy later; can only do it when we |
| 2362 | * do this read in one go (matching page sizes) |
| 2363 | */ |
| 2364 | qemu_get_buffer_in_place(f, (uint8_t **)&place_source, |
| 2365 | TARGET_PAGE_SIZE); |
| 2366 | } |
| 2367 | break; |
| 2368 | case RAM_SAVE_FLAG_EOS: |
| 2369 | /* normal exit */ |
| 2370 | break; |
| 2371 | default: |
| 2372 | error_report("Unknown combination of migration flags: %#x" |
| 2373 | " (postcopy mode)", flags); |
| 2374 | ret = -EINVAL; |
| 2375 | } |
| 2376 | |
| 2377 | if (place_needed) { |
| 2378 | /* This gets called at the last target page in the host page */ |
| 2379 | if (all_zero) { |
| 2380 | ret = postcopy_place_page_zero(mis, |
| 2381 | host + TARGET_PAGE_SIZE - |
| 2382 | qemu_host_page_size); |
| 2383 | } else { |
| 2384 | ret = postcopy_place_page(mis, host + TARGET_PAGE_SIZE - |
| 2385 | qemu_host_page_size, |
| 2386 | place_source); |
| 2387 | } |
| 2388 | } |
| 2389 | if (!ret) { |
| 2390 | ret = qemu_file_get_error(f); |
| 2391 | } |
| 2392 | } |
| 2393 | |
| 2394 | return ret; |
| 2395 | } |
| 2396 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2397 | static int ram_load(QEMUFile *f, void *opaque, int version_id) |
| 2398 | { |
| 2399 | int flags = 0, ret = 0; |
| 2400 | static uint64_t seq_iter; |
| 2401 | int len = 0; |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2402 | /* |
| 2403 | * If system is running in postcopy mode, page inserts to host memory must |
| 2404 | * be atomic |
| 2405 | */ |
| 2406 | bool postcopy_running = postcopy_state_get() >= POSTCOPY_INCOMING_LISTENING; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2407 | |
| 2408 | seq_iter++; |
| 2409 | |
| 2410 | if (version_id != 4) { |
| 2411 | ret = -EINVAL; |
| 2412 | } |
| 2413 | |
| 2414 | /* This RCU critical section can be very long running. |
| 2415 | * When RCU reclaims in the code start to become numerous, |
| 2416 | * it will be necessary to reduce the granularity of this |
| 2417 | * critical section. |
| 2418 | */ |
| 2419 | rcu_read_lock(); |
Dr. David Alan Gilbert | a718087 | 2015-11-05 18:11:11 +0000 | [diff] [blame] | 2420 | |
| 2421 | if (postcopy_running) { |
| 2422 | ret = ram_load_postcopy(f); |
| 2423 | } |
| 2424 | |
| 2425 | while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) { |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2426 | ram_addr_t addr, total_ram_bytes; |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2427 | void *host = NULL; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2428 | uint8_t ch; |
| 2429 | |
| 2430 | addr = qemu_get_be64(f); |
| 2431 | flags = addr & ~TARGET_PAGE_MASK; |
| 2432 | addr &= TARGET_PAGE_MASK; |
| 2433 | |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2434 | if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE | |
| 2435 | RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) { |
| 2436 | host = host_from_stream_offset(f, addr, flags); |
| 2437 | if (!host) { |
| 2438 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); |
| 2439 | ret = -EINVAL; |
| 2440 | break; |
| 2441 | } |
| 2442 | } |
| 2443 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2444 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { |
| 2445 | case RAM_SAVE_FLAG_MEM_SIZE: |
| 2446 | /* Synchronize RAM block list */ |
| 2447 | total_ram_bytes = addr; |
| 2448 | while (!ret && total_ram_bytes) { |
| 2449 | RAMBlock *block; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2450 | char id[256]; |
| 2451 | ram_addr_t length; |
| 2452 | |
| 2453 | len = qemu_get_byte(f); |
| 2454 | qemu_get_buffer(f, (uint8_t *)id, len); |
| 2455 | id[len] = 0; |
| 2456 | length = qemu_get_be64(f); |
| 2457 | |
Dr. David Alan Gilbert | e3dd749 | 2015-11-05 18:10:33 +0000 | [diff] [blame] | 2458 | block = qemu_ram_block_by_name(id); |
| 2459 | if (block) { |
| 2460 | if (length != block->used_length) { |
| 2461 | Error *local_err = NULL; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2462 | |
Dr. David Alan Gilbert | e3dd749 | 2015-11-05 18:10:33 +0000 | [diff] [blame] | 2463 | ret = qemu_ram_resize(block->offset, length, |
| 2464 | &local_err); |
| 2465 | if (local_err) { |
| 2466 | error_report_err(local_err); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2467 | } |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2468 | } |
Dr. David Alan Gilbert | e3dd749 | 2015-11-05 18:10:33 +0000 | [diff] [blame] | 2469 | ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG, |
| 2470 | block->idstr); |
| 2471 | } else { |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2472 | error_report("Unknown ramblock \"%s\", cannot " |
| 2473 | "accept migration", id); |
| 2474 | ret = -EINVAL; |
| 2475 | } |
| 2476 | |
| 2477 | total_ram_bytes -= length; |
| 2478 | } |
| 2479 | break; |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2480 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2481 | case RAM_SAVE_FLAG_COMPRESS: |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2482 | ch = qemu_get_byte(f); |
| 2483 | ram_handle_compressed(host, ch, TARGET_PAGE_SIZE); |
| 2484 | break; |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2485 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2486 | case RAM_SAVE_FLAG_PAGE: |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2487 | qemu_get_buffer(f, host, TARGET_PAGE_SIZE); |
| 2488 | break; |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2489 | |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2490 | case RAM_SAVE_FLAG_COMPRESS_PAGE: |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2491 | len = qemu_get_be32(f); |
| 2492 | if (len < 0 || len > compressBound(TARGET_PAGE_SIZE)) { |
| 2493 | error_report("Invalid compressed data length: %d", len); |
| 2494 | ret = -EINVAL; |
| 2495 | break; |
| 2496 | } |
Dr. David Alan Gilbert | c1bc662 | 2015-12-16 11:47:38 +0000 | [diff] [blame] | 2497 | decompress_data_with_multi_threads(f, host, len); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2498 | break; |
Dr. David Alan Gilbert | a776aa1 | 2015-11-05 18:10:39 +0000 | [diff] [blame] | 2499 | |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2500 | case RAM_SAVE_FLAG_XBZRLE: |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2501 | if (load_xbzrle(f, addr, host) < 0) { |
| 2502 | error_report("Failed to decompress XBZRLE page at " |
| 2503 | RAM_ADDR_FMT, addr); |
| 2504 | ret = -EINVAL; |
| 2505 | break; |
| 2506 | } |
| 2507 | break; |
| 2508 | case RAM_SAVE_FLAG_EOS: |
| 2509 | /* normal exit */ |
| 2510 | break; |
| 2511 | default: |
| 2512 | if (flags & RAM_SAVE_FLAG_HOOK) { |
Dr. David Alan Gilbert | 632e3a5 | 2015-06-11 18:17:23 +0100 | [diff] [blame] | 2513 | ram_control_load_hook(f, RAM_CONTROL_HOOK, NULL); |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2514 | } else { |
| 2515 | error_report("Unknown combination of migration flags: %#x", |
| 2516 | flags); |
| 2517 | ret = -EINVAL; |
| 2518 | } |
| 2519 | } |
| 2520 | if (!ret) { |
| 2521 | ret = qemu_file_get_error(f); |
| 2522 | } |
| 2523 | } |
| 2524 | |
| 2525 | rcu_read_unlock(); |
| 2526 | DPRINTF("Completed load of VM with exit code %d seq iteration " |
| 2527 | "%" PRIu64 "\n", ret, seq_iter); |
| 2528 | return ret; |
| 2529 | } |
| 2530 | |
| 2531 | static SaveVMHandlers savevm_ram_handlers = { |
| 2532 | .save_live_setup = ram_save_setup, |
| 2533 | .save_live_iterate = ram_save_iterate, |
Dr. David Alan Gilbert | 763c906 | 2015-11-05 18:11:00 +0000 | [diff] [blame] | 2534 | .save_live_complete_postcopy = ram_save_complete, |
Dr. David Alan Gilbert | a3e06c3 | 2015-11-05 18:10:41 +0000 | [diff] [blame] | 2535 | .save_live_complete_precopy = ram_save_complete, |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2536 | .save_live_pending = ram_save_pending, |
| 2537 | .load_state = ram_load, |
Liang Li | 6ad2a21 | 2015-11-02 15:37:03 +0800 | [diff] [blame] | 2538 | .cleanup = ram_migration_cleanup, |
Juan Quintela | 56e93d2 | 2015-05-07 19:33:31 +0200 | [diff] [blame] | 2539 | }; |
| 2540 | |
| 2541 | void ram_mig_init(void) |
| 2542 | { |
| 2543 | qemu_mutex_init(&XBZRLE.lock); |
| 2544 | register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, NULL); |
| 2545 | } |