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Commit | Line | Data |
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56e93d26 JQ |
1 | /* |
2 | * QEMU System Emulator | |
3 | * | |
4 | * Copyright (c) 2003-2008 Fabrice Bellard | |
76cc7b58 JQ |
5 | * Copyright (c) 2011-2015 Red Hat Inc |
6 | * | |
7 | * Authors: | |
8 | * Juan Quintela <quintela@redhat.com> | |
56e93d26 JQ |
9 | * |
10 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
11 | * of this software and associated documentation files (the "Software"), to deal | |
12 | * in the Software without restriction, including without limitation the rights | |
13 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
14 | * copies of the Software, and to permit persons to whom the Software is | |
15 | * furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice shall be included in | |
18 | * all copies or substantial portions of the Software. | |
19 | * | |
20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
23 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
24 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
25 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
26 | * THE SOFTWARE. | |
27 | */ | |
e688df6b | 28 | |
1393a485 | 29 | #include "qemu/osdep.h" |
f348b6d1 | 30 | #include "qemu/cutils.h" |
56e93d26 JQ |
31 | #include "qemu/bitops.h" |
32 | #include "qemu/bitmap.h" | |
b85ea5fa | 33 | #include "qemu/madvise.h" |
7205c9ec | 34 | #include "qemu/main-loop.h" |
c0e0825c | 35 | #include "io/channel-null.h" |
709e3fe8 | 36 | #include "xbzrle.h" |
7b1e1a22 | 37 | #include "ram.h" |
6666c96a | 38 | #include "migration.h" |
f2a8f0a6 | 39 | #include "migration/register.h" |
7b1e1a22 | 40 | #include "migration/misc.h" |
08a0aee1 | 41 | #include "qemu-file.h" |
be07b0ac | 42 | #include "postcopy-ram.h" |
53d37d36 | 43 | #include "page_cache.h" |
56e93d26 | 44 | #include "qemu/error-report.h" |
e688df6b | 45 | #include "qapi/error.h" |
ab7cbb0b | 46 | #include "qapi/qapi-types-migration.h" |
9af23989 | 47 | #include "qapi/qapi-events-migration.h" |
8acabf69 | 48 | #include "qapi/qmp/qerror.h" |
56e93d26 | 49 | #include "trace.h" |
56e93d26 | 50 | #include "exec/ram_addr.h" |
f9494614 | 51 | #include "exec/target_page.h" |
56e93d26 | 52 | #include "qemu/rcu_queue.h" |
a91246c9 | 53 | #include "migration/colo.h" |
53d37d36 | 54 | #include "block.h" |
b0c3cf94 | 55 | #include "sysemu/cpu-throttle.h" |
edd090c7 | 56 | #include "savevm.h" |
b9ee2f7d | 57 | #include "qemu/iov.h" |
d32ca5ad | 58 | #include "multifd.h" |
278e2f55 AG |
59 | #include "sysemu/runstate.h" |
60 | ||
e5fdf920 LS |
61 | #include "hw/boards.h" /* for machine_dump_guest_core() */ |
62 | ||
278e2f55 AG |
63 | #if defined(__linux__) |
64 | #include "qemu/userfaultfd.h" | |
65 | #endif /* defined(__linux__) */ | |
56e93d26 | 66 | |
56e93d26 JQ |
67 | /***********************************************************/ |
68 | /* ram save/restore */ | |
69 | ||
7b548761 JQ |
70 | /* |
71 | * RAM_SAVE_FLAG_ZERO used to be named RAM_SAVE_FLAG_COMPRESS, it | |
72 | * worked for pages that were filled with the same char. We switched | |
bb890ed5 | 73 | * it to only search for the zero value. And to avoid confusion with |
7b548761 | 74 | * RAM_SAVE_FLAG_COMPRESS_PAGE just rename it. |
bb890ed5 | 75 | */ |
7b548761 JQ |
76 | /* |
77 | * RAM_SAVE_FLAG_FULL was obsoleted in 2009, it can be reused now | |
78 | */ | |
79 | #define RAM_SAVE_FLAG_FULL 0x01 | |
bb890ed5 | 80 | #define RAM_SAVE_FLAG_ZERO 0x02 |
56e93d26 JQ |
81 | #define RAM_SAVE_FLAG_MEM_SIZE 0x04 |
82 | #define RAM_SAVE_FLAG_PAGE 0x08 | |
83 | #define RAM_SAVE_FLAG_EOS 0x10 | |
84 | #define RAM_SAVE_FLAG_CONTINUE 0x20 | |
85 | #define RAM_SAVE_FLAG_XBZRLE 0x40 | |
7b548761 | 86 | /* 0x80 is reserved in qemu-file.h for RAM_SAVE_FLAG_HOOK */ |
56e93d26 | 87 | #define RAM_SAVE_FLAG_COMPRESS_PAGE 0x100 |
7b548761 | 88 | /* We can't use any flag that is bigger than 0x200 */ |
56e93d26 | 89 | |
04ffce13 | 90 | int (*xbzrle_encode_buffer_func)(uint8_t *, uint8_t *, int, |
91 | uint8_t *, int) = xbzrle_encode_buffer; | |
92 | #if defined(CONFIG_AVX512BW_OPT) | |
93 | #include "qemu/cpuid.h" | |
94 | static void __attribute__((constructor)) init_cpu_flag(void) | |
95 | { | |
96 | unsigned max = __get_cpuid_max(0, NULL); | |
97 | int a, b, c, d; | |
98 | if (max >= 1) { | |
99 | __cpuid(1, a, b, c, d); | |
100 | /* We must check that AVX is not just available, but usable. */ | |
101 | if ((c & bit_OSXSAVE) && (c & bit_AVX) && max >= 7) { | |
102 | int bv; | |
103 | __asm("xgetbv" : "=a"(bv), "=d"(d) : "c"(0)); | |
104 | __cpuid_count(7, 0, a, b, c, d); | |
105 | /* 0xe6: | |
106 | * XCR0[7:5] = 111b (OPMASK state, upper 256-bit of ZMM0-ZMM15 | |
107 | * and ZMM16-ZMM31 state are enabled by OS) | |
108 | * XCR0[2:1] = 11b (XMM state and YMM state are enabled by OS) | |
109 | */ | |
110 | if ((bv & 0xe6) == 0xe6 && (b & bit_AVX512BW)) { | |
111 | xbzrle_encode_buffer_func = xbzrle_encode_buffer_avx512; | |
112 | } | |
113 | } | |
114 | } | |
115 | } | |
116 | #endif | |
117 | ||
9360447d JQ |
118 | XBZRLECacheStats xbzrle_counters; |
119 | ||
f1668764 PX |
120 | /* used by the search for pages to send */ |
121 | struct PageSearchStatus { | |
122 | /* The migration channel used for a specific host page */ | |
123 | QEMUFile *pss_channel; | |
ec6f3ab9 PX |
124 | /* Last block from where we have sent data */ |
125 | RAMBlock *last_sent_block; | |
f1668764 PX |
126 | /* Current block being searched */ |
127 | RAMBlock *block; | |
128 | /* Current page to search from */ | |
129 | unsigned long page; | |
130 | /* Set once we wrap around */ | |
131 | bool complete_round; | |
f1668764 PX |
132 | /* Whether we're sending a host page */ |
133 | bool host_page_sending; | |
134 | /* The start/end of current host page. Invalid if host_page_sending==false */ | |
135 | unsigned long host_page_start; | |
136 | unsigned long host_page_end; | |
137 | }; | |
138 | typedef struct PageSearchStatus PageSearchStatus; | |
139 | ||
56e93d26 JQ |
140 | /* struct contains XBZRLE cache and a static page |
141 | used by the compression */ | |
142 | static struct { | |
143 | /* buffer used for XBZRLE encoding */ | |
144 | uint8_t *encoded_buf; | |
145 | /* buffer for storing page content */ | |
146 | uint8_t *current_buf; | |
147 | /* Cache for XBZRLE, Protected by lock. */ | |
148 | PageCache *cache; | |
149 | QemuMutex lock; | |
c00e0928 JQ |
150 | /* it will store a page full of zeros */ |
151 | uint8_t *zero_target_page; | |
f265e0e4 JQ |
152 | /* buffer used for XBZRLE decoding */ |
153 | uint8_t *decoded_buf; | |
56e93d26 JQ |
154 | } XBZRLE; |
155 | ||
56e93d26 JQ |
156 | static void XBZRLE_cache_lock(void) |
157 | { | |
f4c51a6b | 158 | if (migrate_use_xbzrle()) { |
56e93d26 | 159 | qemu_mutex_lock(&XBZRLE.lock); |
f4c51a6b | 160 | } |
56e93d26 JQ |
161 | } |
162 | ||
163 | static void XBZRLE_cache_unlock(void) | |
164 | { | |
f4c51a6b | 165 | if (migrate_use_xbzrle()) { |
56e93d26 | 166 | qemu_mutex_unlock(&XBZRLE.lock); |
f4c51a6b | 167 | } |
56e93d26 JQ |
168 | } |
169 | ||
3d0684b2 JQ |
170 | /** |
171 | * xbzrle_cache_resize: resize the xbzrle cache | |
172 | * | |
cbde7be9 | 173 | * This function is called from migrate_params_apply in main |
3d0684b2 JQ |
174 | * thread, possibly while a migration is in progress. A running |
175 | * migration may be using the cache and might finish during this call, | |
176 | * hence changes to the cache are protected by XBZRLE.lock(). | |
177 | * | |
c9dede2d | 178 | * Returns 0 for success or -1 for error |
3d0684b2 JQ |
179 | * |
180 | * @new_size: new cache size | |
8acabf69 | 181 | * @errp: set *errp if the check failed, with reason |
56e93d26 | 182 | */ |
8b9407a0 | 183 | int xbzrle_cache_resize(uint64_t new_size, Error **errp) |
56e93d26 JQ |
184 | { |
185 | PageCache *new_cache; | |
c9dede2d | 186 | int64_t ret = 0; |
56e93d26 | 187 | |
8acabf69 JQ |
188 | /* Check for truncation */ |
189 | if (new_size != (size_t)new_size) { | |
190 | error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size", | |
191 | "exceeding address space"); | |
192 | return -1; | |
193 | } | |
194 | ||
2a313e5c JQ |
195 | if (new_size == migrate_xbzrle_cache_size()) { |
196 | /* nothing to do */ | |
c9dede2d | 197 | return 0; |
2a313e5c JQ |
198 | } |
199 | ||
56e93d26 JQ |
200 | XBZRLE_cache_lock(); |
201 | ||
202 | if (XBZRLE.cache != NULL) { | |
80f8dfde | 203 | new_cache = cache_init(new_size, TARGET_PAGE_SIZE, errp); |
56e93d26 | 204 | if (!new_cache) { |
56e93d26 JQ |
205 | ret = -1; |
206 | goto out; | |
207 | } | |
208 | ||
209 | cache_fini(XBZRLE.cache); | |
210 | XBZRLE.cache = new_cache; | |
211 | } | |
56e93d26 JQ |
212 | out: |
213 | XBZRLE_cache_unlock(); | |
214 | return ret; | |
215 | } | |
216 | ||
20123ee1 PX |
217 | static bool postcopy_preempt_active(void) |
218 | { | |
219 | return migrate_postcopy_preempt() && migration_in_postcopy(); | |
220 | } | |
221 | ||
3ded54b1 | 222 | bool ramblock_is_ignored(RAMBlock *block) |
fbd162e6 YK |
223 | { |
224 | return !qemu_ram_is_migratable(block) || | |
225 | (migrate_ignore_shared() && qemu_ram_is_shared(block)); | |
226 | } | |
227 | ||
343f632c DDAG |
228 | #undef RAMBLOCK_FOREACH |
229 | ||
fbd162e6 YK |
230 | int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque) |
231 | { | |
232 | RAMBlock *block; | |
233 | int ret = 0; | |
234 | ||
89ac5a1d DDAG |
235 | RCU_READ_LOCK_GUARD(); |
236 | ||
fbd162e6 YK |
237 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
238 | ret = func(block, opaque); | |
239 | if (ret) { | |
240 | break; | |
241 | } | |
242 | } | |
fbd162e6 YK |
243 | return ret; |
244 | } | |
245 | ||
f9494614 AP |
246 | static void ramblock_recv_map_init(void) |
247 | { | |
248 | RAMBlock *rb; | |
249 | ||
fbd162e6 | 250 | RAMBLOCK_FOREACH_NOT_IGNORED(rb) { |
f9494614 AP |
251 | assert(!rb->receivedmap); |
252 | rb->receivedmap = bitmap_new(rb->max_length >> qemu_target_page_bits()); | |
253 | } | |
254 | } | |
255 | ||
256 | int ramblock_recv_bitmap_test(RAMBlock *rb, void *host_addr) | |
257 | { | |
258 | return test_bit(ramblock_recv_bitmap_offset(host_addr, rb), | |
259 | rb->receivedmap); | |
260 | } | |
261 | ||
1cba9f6e DDAG |
262 | bool ramblock_recv_bitmap_test_byte_offset(RAMBlock *rb, uint64_t byte_offset) |
263 | { | |
264 | return test_bit(byte_offset >> TARGET_PAGE_BITS, rb->receivedmap); | |
265 | } | |
266 | ||
f9494614 AP |
267 | void ramblock_recv_bitmap_set(RAMBlock *rb, void *host_addr) |
268 | { | |
269 | set_bit_atomic(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap); | |
270 | } | |
271 | ||
272 | void ramblock_recv_bitmap_set_range(RAMBlock *rb, void *host_addr, | |
273 | size_t nr) | |
274 | { | |
275 | bitmap_set_atomic(rb->receivedmap, | |
276 | ramblock_recv_bitmap_offset(host_addr, rb), | |
277 | nr); | |
278 | } | |
279 | ||
a335debb PX |
280 | #define RAMBLOCK_RECV_BITMAP_ENDING (0x0123456789abcdefULL) |
281 | ||
282 | /* | |
283 | * Format: bitmap_size (8 bytes) + whole_bitmap (N bytes). | |
284 | * | |
285 | * Returns >0 if success with sent bytes, or <0 if error. | |
286 | */ | |
287 | int64_t ramblock_recv_bitmap_send(QEMUFile *file, | |
288 | const char *block_name) | |
289 | { | |
290 | RAMBlock *block = qemu_ram_block_by_name(block_name); | |
291 | unsigned long *le_bitmap, nbits; | |
292 | uint64_t size; | |
293 | ||
294 | if (!block) { | |
295 | error_report("%s: invalid block name: %s", __func__, block_name); | |
296 | return -1; | |
297 | } | |
298 | ||
898ba906 | 299 | nbits = block->postcopy_length >> TARGET_PAGE_BITS; |
a335debb PX |
300 | |
301 | /* | |
302 | * Make sure the tmp bitmap buffer is big enough, e.g., on 32bit | |
303 | * machines we may need 4 more bytes for padding (see below | |
304 | * comment). So extend it a bit before hand. | |
305 | */ | |
306 | le_bitmap = bitmap_new(nbits + BITS_PER_LONG); | |
307 | ||
308 | /* | |
309 | * Always use little endian when sending the bitmap. This is | |
310 | * required that when source and destination VMs are not using the | |
3a4452d8 | 311 | * same endianness. (Note: big endian won't work.) |
a335debb PX |
312 | */ |
313 | bitmap_to_le(le_bitmap, block->receivedmap, nbits); | |
314 | ||
315 | /* Size of the bitmap, in bytes */ | |
a725ef9f | 316 | size = DIV_ROUND_UP(nbits, 8); |
a335debb PX |
317 | |
318 | /* | |
319 | * size is always aligned to 8 bytes for 64bit machines, but it | |
320 | * may not be true for 32bit machines. We need this padding to | |
321 | * make sure the migration can survive even between 32bit and | |
322 | * 64bit machines. | |
323 | */ | |
324 | size = ROUND_UP(size, 8); | |
325 | ||
326 | qemu_put_be64(file, size); | |
327 | qemu_put_buffer(file, (const uint8_t *)le_bitmap, size); | |
328 | /* | |
329 | * Mark as an end, in case the middle part is screwed up due to | |
3a4452d8 | 330 | * some "mysterious" reason. |
a335debb PX |
331 | */ |
332 | qemu_put_be64(file, RAMBLOCK_RECV_BITMAP_ENDING); | |
333 | qemu_fflush(file); | |
334 | ||
bf269906 | 335 | g_free(le_bitmap); |
a335debb PX |
336 | |
337 | if (qemu_file_get_error(file)) { | |
338 | return qemu_file_get_error(file); | |
339 | } | |
340 | ||
341 | return size + sizeof(size); | |
342 | } | |
343 | ||
ec481c6c JQ |
344 | /* |
345 | * An outstanding page request, on the source, having been received | |
346 | * and queued | |
347 | */ | |
348 | struct RAMSrcPageRequest { | |
349 | RAMBlock *rb; | |
350 | hwaddr offset; | |
351 | hwaddr len; | |
352 | ||
353 | QSIMPLEQ_ENTRY(RAMSrcPageRequest) next_req; | |
354 | }; | |
355 | ||
6f37bb8b JQ |
356 | /* State of RAM for migration */ |
357 | struct RAMState { | |
f1668764 PX |
358 | /* |
359 | * PageSearchStatus structures for the channels when send pages. | |
360 | * Protected by the bitmap_mutex. | |
361 | */ | |
362 | PageSearchStatus pss[RAM_CHANNEL_MAX]; | |
278e2f55 AG |
363 | /* UFFD file descriptor, used in 'write-tracking' migration */ |
364 | int uffdio_fd; | |
8d80e195 JQ |
365 | /* total ram size in bytes */ |
366 | uint64_t ram_bytes_total; | |
6f37bb8b JQ |
367 | /* Last block that we have visited searching for dirty pages */ |
368 | RAMBlock *last_seen_block; | |
269ace29 JQ |
369 | /* Last dirty target page we have sent */ |
370 | ram_addr_t last_page; | |
6f37bb8b JQ |
371 | /* last ram version we have seen */ |
372 | uint32_t last_version; | |
8d820d6f JQ |
373 | /* How many times we have dirty too many pages */ |
374 | int dirty_rate_high_cnt; | |
f664da80 JQ |
375 | /* these variables are used for bitmap sync */ |
376 | /* last time we did a full bitmap_sync */ | |
377 | int64_t time_last_bitmap_sync; | |
eac74159 | 378 | /* bytes transferred at start_time */ |
c4bdf0cf | 379 | uint64_t bytes_xfer_prev; |
a66cd90c | 380 | /* number of dirty pages since start_time */ |
68908ed6 | 381 | uint64_t num_dirty_pages_period; |
b5833fde JQ |
382 | /* xbzrle misses since the beginning of the period */ |
383 | uint64_t xbzrle_cache_miss_prev; | |
e460a4b1 WW |
384 | /* Amount of xbzrle pages since the beginning of the period */ |
385 | uint64_t xbzrle_pages_prev; | |
386 | /* Amount of xbzrle encoded bytes since the beginning of the period */ | |
387 | uint64_t xbzrle_bytes_prev; | |
1a373522 DH |
388 | /* Start using XBZRLE (e.g., after the first round). */ |
389 | bool xbzrle_enabled; | |
05931ec5 JQ |
390 | /* Are we on the last stage of migration */ |
391 | bool last_stage; | |
76e03000 XG |
392 | /* compression statistics since the beginning of the period */ |
393 | /* amount of count that no free thread to compress data */ | |
394 | uint64_t compress_thread_busy_prev; | |
395 | /* amount bytes after compression */ | |
396 | uint64_t compressed_size_prev; | |
397 | /* amount of compressed pages */ | |
398 | uint64_t compress_pages_prev; | |
399 | ||
be8b02ed XG |
400 | /* total handled target pages at the beginning of period */ |
401 | uint64_t target_page_count_prev; | |
402 | /* total handled target pages since start */ | |
403 | uint64_t target_page_count; | |
9360447d | 404 | /* number of dirty bits in the bitmap */ |
2dfaf12e | 405 | uint64_t migration_dirty_pages; |
f1668764 PX |
406 | /* |
407 | * Protects: | |
408 | * - dirty/clear bitmap | |
409 | * - migration_dirty_pages | |
410 | * - pss structures | |
411 | */ | |
108cfae0 | 412 | QemuMutex bitmap_mutex; |
68a098f3 JQ |
413 | /* The RAMBlock used in the last src_page_requests */ |
414 | RAMBlock *last_req_rb; | |
ec481c6c JQ |
415 | /* Queue of outstanding page requests from the destination */ |
416 | QemuMutex src_page_req_mutex; | |
b58deb34 | 417 | QSIMPLEQ_HEAD(, RAMSrcPageRequest) src_page_requests; |
6f37bb8b JQ |
418 | }; |
419 | typedef struct RAMState RAMState; | |
420 | ||
53518d94 | 421 | static RAMState *ram_state; |
6f37bb8b | 422 | |
bd227060 WW |
423 | static NotifierWithReturnList precopy_notifier_list; |
424 | ||
a1fe28df PX |
425 | /* Whether postcopy has queued requests? */ |
426 | static bool postcopy_has_request(RAMState *rs) | |
427 | { | |
428 | return !QSIMPLEQ_EMPTY_ATOMIC(&rs->src_page_requests); | |
429 | } | |
430 | ||
bd227060 WW |
431 | void precopy_infrastructure_init(void) |
432 | { | |
433 | notifier_with_return_list_init(&precopy_notifier_list); | |
434 | } | |
435 | ||
436 | void precopy_add_notifier(NotifierWithReturn *n) | |
437 | { | |
438 | notifier_with_return_list_add(&precopy_notifier_list, n); | |
439 | } | |
440 | ||
441 | void precopy_remove_notifier(NotifierWithReturn *n) | |
442 | { | |
443 | notifier_with_return_remove(n); | |
444 | } | |
445 | ||
446 | int precopy_notify(PrecopyNotifyReason reason, Error **errp) | |
447 | { | |
448 | PrecopyNotifyData pnd; | |
449 | pnd.reason = reason; | |
450 | pnd.errp = errp; | |
451 | ||
452 | return notifier_with_return_list_notify(&precopy_notifier_list, &pnd); | |
453 | } | |
454 | ||
9edabd4d | 455 | uint64_t ram_bytes_remaining(void) |
2f4fde93 | 456 | { |
bae416e5 DDAG |
457 | return ram_state ? (ram_state->migration_dirty_pages * TARGET_PAGE_SIZE) : |
458 | 0; | |
2f4fde93 JQ |
459 | } |
460 | ||
abce5fa1 | 461 | RAMStats ram_counters; |
96506894 | 462 | |
26a26069 | 463 | void ram_transferred_add(uint64_t bytes) |
4c2d0f6d | 464 | { |
ae680668 DE |
465 | if (runstate_is_running()) { |
466 | ram_counters.precopy_bytes += bytes; | |
467 | } else if (migration_in_postcopy()) { | |
abce5fa1 | 468 | stat64_add(&ram_counters.postcopy_bytes, bytes); |
ae680668 DE |
469 | } else { |
470 | ram_counters.downtime_bytes += bytes; | |
471 | } | |
abce5fa1 | 472 | stat64_add(&ram_counters.transferred, bytes); |
4c2d0f6d DE |
473 | } |
474 | ||
4010ba38 JQ |
475 | struct MigrationOps { |
476 | int (*ram_save_target_page)(RAMState *rs, PageSearchStatus *pss); | |
477 | }; | |
478 | typedef struct MigrationOps MigrationOps; | |
479 | ||
480 | MigrationOps *migration_ops; | |
481 | ||
76e03000 XG |
482 | CompressionStats compression_counters; |
483 | ||
56e93d26 | 484 | struct CompressParam { |
56e93d26 | 485 | bool done; |
90e56fb4 | 486 | bool quit; |
5e5fdcff | 487 | bool zero_page; |
56e93d26 JQ |
488 | QEMUFile *file; |
489 | QemuMutex mutex; | |
490 | QemuCond cond; | |
491 | RAMBlock *block; | |
492 | ram_addr_t offset; | |
34ab9e97 XG |
493 | |
494 | /* internally used fields */ | |
dcaf446e | 495 | z_stream stream; |
34ab9e97 | 496 | uint8_t *originbuf; |
56e93d26 JQ |
497 | }; |
498 | typedef struct CompressParam CompressParam; | |
499 | ||
500 | struct DecompressParam { | |
73a8912b | 501 | bool done; |
90e56fb4 | 502 | bool quit; |
56e93d26 JQ |
503 | QemuMutex mutex; |
504 | QemuCond cond; | |
505 | void *des; | |
d341d9f3 | 506 | uint8_t *compbuf; |
56e93d26 | 507 | int len; |
797ca154 | 508 | z_stream stream; |
56e93d26 JQ |
509 | }; |
510 | typedef struct DecompressParam DecompressParam; | |
511 | ||
512 | static CompressParam *comp_param; | |
513 | static QemuThread *compress_threads; | |
514 | /* comp_done_cond is used to wake up the migration thread when | |
515 | * one of the compression threads has finished the compression. | |
516 | * comp_done_lock is used to co-work with comp_done_cond. | |
517 | */ | |
0d9f9a5c LL |
518 | static QemuMutex comp_done_lock; |
519 | static QemuCond comp_done_cond; | |
56e93d26 | 520 | |
34ab9e97 | 521 | static QEMUFile *decomp_file; |
56e93d26 JQ |
522 | static DecompressParam *decomp_param; |
523 | static QemuThread *decompress_threads; | |
73a8912b LL |
524 | static QemuMutex decomp_done_lock; |
525 | static QemuCond decomp_done_cond; | |
56e93d26 | 526 | |
93589827 PX |
527 | static int ram_save_host_page_urgent(PageSearchStatus *pss); |
528 | ||
5e5fdcff | 529 | static bool do_compress_ram_page(QEMUFile *f, z_stream *stream, RAMBlock *block, |
6ef3771c | 530 | ram_addr_t offset, uint8_t *source_buf); |
56e93d26 | 531 | |
ebd88a49 PX |
532 | /* NOTE: page is the PFN not real ram_addr_t. */ |
533 | static void pss_init(PageSearchStatus *pss, RAMBlock *rb, ram_addr_t page) | |
534 | { | |
535 | pss->block = rb; | |
536 | pss->page = page; | |
537 | pss->complete_round = false; | |
538 | } | |
539 | ||
93589827 PX |
540 | /* |
541 | * Check whether two PSSs are actively sending the same page. Return true | |
542 | * if it is, false otherwise. | |
543 | */ | |
544 | static bool pss_overlap(PageSearchStatus *pss1, PageSearchStatus *pss2) | |
545 | { | |
546 | return pss1->host_page_sending && pss2->host_page_sending && | |
547 | (pss1->host_page_start == pss2->host_page_start); | |
548 | } | |
549 | ||
56e93d26 JQ |
550 | static void *do_data_compress(void *opaque) |
551 | { | |
552 | CompressParam *param = opaque; | |
a7a9a88f LL |
553 | RAMBlock *block; |
554 | ram_addr_t offset; | |
5e5fdcff | 555 | bool zero_page; |
56e93d26 | 556 | |
a7a9a88f | 557 | qemu_mutex_lock(¶m->mutex); |
90e56fb4 | 558 | while (!param->quit) { |
a7a9a88f LL |
559 | if (param->block) { |
560 | block = param->block; | |
561 | offset = param->offset; | |
562 | param->block = NULL; | |
563 | qemu_mutex_unlock(¶m->mutex); | |
564 | ||
5e5fdcff XG |
565 | zero_page = do_compress_ram_page(param->file, ¶m->stream, |
566 | block, offset, param->originbuf); | |
a7a9a88f | 567 | |
0d9f9a5c | 568 | qemu_mutex_lock(&comp_done_lock); |
a7a9a88f | 569 | param->done = true; |
5e5fdcff | 570 | param->zero_page = zero_page; |
0d9f9a5c LL |
571 | qemu_cond_signal(&comp_done_cond); |
572 | qemu_mutex_unlock(&comp_done_lock); | |
a7a9a88f LL |
573 | |
574 | qemu_mutex_lock(¶m->mutex); | |
575 | } else { | |
56e93d26 JQ |
576 | qemu_cond_wait(¶m->cond, ¶m->mutex); |
577 | } | |
56e93d26 | 578 | } |
a7a9a88f | 579 | qemu_mutex_unlock(¶m->mutex); |
56e93d26 JQ |
580 | |
581 | return NULL; | |
582 | } | |
583 | ||
f0afa331 | 584 | static void compress_threads_save_cleanup(void) |
56e93d26 JQ |
585 | { |
586 | int i, thread_count; | |
587 | ||
05306935 | 588 | if (!migrate_use_compression() || !comp_param) { |
56e93d26 JQ |
589 | return; |
590 | } | |
05306935 | 591 | |
56e93d26 JQ |
592 | thread_count = migrate_compress_threads(); |
593 | for (i = 0; i < thread_count; i++) { | |
dcaf446e XG |
594 | /* |
595 | * we use it as a indicator which shows if the thread is | |
596 | * properly init'd or not | |
597 | */ | |
598 | if (!comp_param[i].file) { | |
599 | break; | |
600 | } | |
05306935 FL |
601 | |
602 | qemu_mutex_lock(&comp_param[i].mutex); | |
603 | comp_param[i].quit = true; | |
604 | qemu_cond_signal(&comp_param[i].cond); | |
605 | qemu_mutex_unlock(&comp_param[i].mutex); | |
606 | ||
56e93d26 | 607 | qemu_thread_join(compress_threads + i); |
56e93d26 JQ |
608 | qemu_mutex_destroy(&comp_param[i].mutex); |
609 | qemu_cond_destroy(&comp_param[i].cond); | |
dcaf446e | 610 | deflateEnd(&comp_param[i].stream); |
34ab9e97 | 611 | g_free(comp_param[i].originbuf); |
dcaf446e XG |
612 | qemu_fclose(comp_param[i].file); |
613 | comp_param[i].file = NULL; | |
56e93d26 | 614 | } |
0d9f9a5c LL |
615 | qemu_mutex_destroy(&comp_done_lock); |
616 | qemu_cond_destroy(&comp_done_cond); | |
56e93d26 JQ |
617 | g_free(compress_threads); |
618 | g_free(comp_param); | |
56e93d26 JQ |
619 | compress_threads = NULL; |
620 | comp_param = NULL; | |
56e93d26 JQ |
621 | } |
622 | ||
dcaf446e | 623 | static int compress_threads_save_setup(void) |
56e93d26 JQ |
624 | { |
625 | int i, thread_count; | |
626 | ||
627 | if (!migrate_use_compression()) { | |
dcaf446e | 628 | return 0; |
56e93d26 | 629 | } |
56e93d26 JQ |
630 | thread_count = migrate_compress_threads(); |
631 | compress_threads = g_new0(QemuThread, thread_count); | |
632 | comp_param = g_new0(CompressParam, thread_count); | |
0d9f9a5c LL |
633 | qemu_cond_init(&comp_done_cond); |
634 | qemu_mutex_init(&comp_done_lock); | |
56e93d26 | 635 | for (i = 0; i < thread_count; i++) { |
34ab9e97 XG |
636 | comp_param[i].originbuf = g_try_malloc(TARGET_PAGE_SIZE); |
637 | if (!comp_param[i].originbuf) { | |
638 | goto exit; | |
639 | } | |
640 | ||
dcaf446e XG |
641 | if (deflateInit(&comp_param[i].stream, |
642 | migrate_compress_level()) != Z_OK) { | |
34ab9e97 | 643 | g_free(comp_param[i].originbuf); |
dcaf446e XG |
644 | goto exit; |
645 | } | |
646 | ||
e110aa91 C |
647 | /* comp_param[i].file is just used as a dummy buffer to save data, |
648 | * set its ops to empty. | |
56e93d26 | 649 | */ |
77ef2dc1 | 650 | comp_param[i].file = qemu_file_new_output( |
c0e0825c | 651 | QIO_CHANNEL(qio_channel_null_new())); |
56e93d26 | 652 | comp_param[i].done = true; |
90e56fb4 | 653 | comp_param[i].quit = false; |
56e93d26 JQ |
654 | qemu_mutex_init(&comp_param[i].mutex); |
655 | qemu_cond_init(&comp_param[i].cond); | |
656 | qemu_thread_create(compress_threads + i, "compress", | |
657 | do_data_compress, comp_param + i, | |
658 | QEMU_THREAD_JOINABLE); | |
659 | } | |
dcaf446e XG |
660 | return 0; |
661 | ||
662 | exit: | |
663 | compress_threads_save_cleanup(); | |
664 | return -1; | |
56e93d26 JQ |
665 | } |
666 | ||
667 | /** | |
3d0684b2 | 668 | * save_page_header: write page header to wire |
56e93d26 JQ |
669 | * |
670 | * If this is the 1st block, it also writes the block identification | |
671 | * | |
3d0684b2 | 672 | * Returns the number of bytes written |
56e93d26 | 673 | * |
ec6f3ab9 | 674 | * @pss: current PSS channel status |
56e93d26 JQ |
675 | * @block: block that contains the page we want to send |
676 | * @offset: offset inside the block for the page | |
677 | * in the lower bits, it contains flags | |
678 | */ | |
37502df3 LS |
679 | static size_t save_page_header(PageSearchStatus *pss, QEMUFile *f, |
680 | RAMBlock *block, ram_addr_t offset) | |
56e93d26 | 681 | { |
9f5f380b | 682 | size_t size, len; |
ec6f3ab9 | 683 | bool same_block = (block == pss->last_sent_block); |
56e93d26 | 684 | |
10661f11 | 685 | if (same_block) { |
24795694 JQ |
686 | offset |= RAM_SAVE_FLAG_CONTINUE; |
687 | } | |
2bf3aa85 | 688 | qemu_put_be64(f, offset); |
56e93d26 JQ |
689 | size = 8; |
690 | ||
10661f11 | 691 | if (!same_block) { |
9f5f380b | 692 | len = strlen(block->idstr); |
2bf3aa85 JQ |
693 | qemu_put_byte(f, len); |
694 | qemu_put_buffer(f, (uint8_t *)block->idstr, len); | |
9f5f380b | 695 | size += 1 + len; |
ec6f3ab9 | 696 | pss->last_sent_block = block; |
56e93d26 JQ |
697 | } |
698 | return size; | |
699 | } | |
700 | ||
3d0684b2 | 701 | /** |
179a8080 | 702 | * mig_throttle_guest_down: throttle down the guest |
3d0684b2 JQ |
703 | * |
704 | * Reduce amount of guest cpu execution to hopefully slow down memory | |
705 | * writes. If guest dirty memory rate is reduced below the rate at | |
706 | * which we can transfer pages to the destination then we should be | |
707 | * able to complete migration. Some workloads dirty memory way too | |
708 | * fast and will not effectively converge, even with auto-converge. | |
070afca2 | 709 | */ |
cbbf8182 KZ |
710 | static void mig_throttle_guest_down(uint64_t bytes_dirty_period, |
711 | uint64_t bytes_dirty_threshold) | |
070afca2 JH |
712 | { |
713 | MigrationState *s = migrate_get_current(); | |
2594f56d | 714 | uint64_t pct_initial = s->parameters.cpu_throttle_initial; |
cbbf8182 KZ |
715 | uint64_t pct_increment = s->parameters.cpu_throttle_increment; |
716 | bool pct_tailslow = s->parameters.cpu_throttle_tailslow; | |
4cbc9c7f | 717 | int pct_max = s->parameters.max_cpu_throttle; |
070afca2 | 718 | |
cbbf8182 KZ |
719 | uint64_t throttle_now = cpu_throttle_get_percentage(); |
720 | uint64_t cpu_now, cpu_ideal, throttle_inc; | |
721 | ||
070afca2 JH |
722 | /* We have not started throttling yet. Let's start it. */ |
723 | if (!cpu_throttle_active()) { | |
724 | cpu_throttle_set(pct_initial); | |
725 | } else { | |
726 | /* Throttling already on, just increase the rate */ | |
cbbf8182 KZ |
727 | if (!pct_tailslow) { |
728 | throttle_inc = pct_increment; | |
729 | } else { | |
730 | /* Compute the ideal CPU percentage used by Guest, which may | |
731 | * make the dirty rate match the dirty rate threshold. */ | |
732 | cpu_now = 100 - throttle_now; | |
733 | cpu_ideal = cpu_now * (bytes_dirty_threshold * 1.0 / | |
734 | bytes_dirty_period); | |
735 | throttle_inc = MIN(cpu_now - cpu_ideal, pct_increment); | |
736 | } | |
737 | cpu_throttle_set(MIN(throttle_now + throttle_inc, pct_max)); | |
070afca2 JH |
738 | } |
739 | } | |
740 | ||
91fe9a8d RL |
741 | void mig_throttle_counter_reset(void) |
742 | { | |
743 | RAMState *rs = ram_state; | |
744 | ||
745 | rs->time_last_bitmap_sync = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); | |
746 | rs->num_dirty_pages_period = 0; | |
abce5fa1 | 747 | rs->bytes_xfer_prev = stat64_get(&ram_counters.transferred); |
91fe9a8d RL |
748 | } |
749 | ||
3d0684b2 JQ |
750 | /** |
751 | * xbzrle_cache_zero_page: insert a zero page in the XBZRLE cache | |
752 | * | |
6f37bb8b | 753 | * @rs: current RAM state |
3d0684b2 JQ |
754 | * @current_addr: address for the zero page |
755 | * | |
756 | * Update the xbzrle cache to reflect a page that's been sent as all 0. | |
56e93d26 JQ |
757 | * The important thing is that a stale (not-yet-0'd) page be replaced |
758 | * by the new data. | |
759 | * As a bonus, if the page wasn't in the cache it gets added so that | |
3d0684b2 | 760 | * when a small write is made into the 0'd page it gets XBZRLE sent. |
56e93d26 | 761 | */ |
6f37bb8b | 762 | static void xbzrle_cache_zero_page(RAMState *rs, ram_addr_t current_addr) |
56e93d26 | 763 | { |
56e93d26 JQ |
764 | /* We don't care if this fails to allocate a new cache page |
765 | * as long as it updated an old one */ | |
c00e0928 | 766 | cache_insert(XBZRLE.cache, current_addr, XBZRLE.zero_target_page, |
9360447d | 767 | ram_counters.dirty_sync_count); |
56e93d26 JQ |
768 | } |
769 | ||
770 | #define ENCODING_FLAG_XBZRLE 0x1 | |
771 | ||
772 | /** | |
773 | * save_xbzrle_page: compress and send current page | |
774 | * | |
775 | * Returns: 1 means that we wrote the page | |
776 | * 0 means that page is identical to the one already sent | |
777 | * -1 means that xbzrle would be longer than normal | |
778 | * | |
5a987738 | 779 | * @rs: current RAM state |
ec6f3ab9 | 780 | * @pss: current PSS channel |
3d0684b2 JQ |
781 | * @current_data: pointer to the address of the page contents |
782 | * @current_addr: addr of the page | |
56e93d26 JQ |
783 | * @block: block that contains the page we want to send |
784 | * @offset: offset inside the block for the page | |
56e93d26 | 785 | */ |
ec6f3ab9 | 786 | static int save_xbzrle_page(RAMState *rs, PageSearchStatus *pss, |
61717ea9 PX |
787 | uint8_t **current_data, ram_addr_t current_addr, |
788 | RAMBlock *block, ram_addr_t offset) | |
56e93d26 JQ |
789 | { |
790 | int encoded_len = 0, bytes_xbzrle; | |
791 | uint8_t *prev_cached_page; | |
ec6f3ab9 | 792 | QEMUFile *file = pss->pss_channel; |
56e93d26 | 793 | |
9360447d JQ |
794 | if (!cache_is_cached(XBZRLE.cache, current_addr, |
795 | ram_counters.dirty_sync_count)) { | |
796 | xbzrle_counters.cache_miss++; | |
05931ec5 | 797 | if (!rs->last_stage) { |
56e93d26 | 798 | if (cache_insert(XBZRLE.cache, current_addr, *current_data, |
9360447d | 799 | ram_counters.dirty_sync_count) == -1) { |
56e93d26 JQ |
800 | return -1; |
801 | } else { | |
802 | /* update *current_data when the page has been | |
803 | inserted into cache */ | |
804 | *current_data = get_cached_data(XBZRLE.cache, current_addr); | |
805 | } | |
806 | } | |
807 | return -1; | |
808 | } | |
809 | ||
e460a4b1 WW |
810 | /* |
811 | * Reaching here means the page has hit the xbzrle cache, no matter what | |
812 | * encoding result it is (normal encoding, overflow or skipping the page), | |
3a4452d8 | 813 | * count the page as encoded. This is used to calculate the encoding rate. |
e460a4b1 WW |
814 | * |
815 | * Example: 2 pages (8KB) being encoded, first page encoding generates 2KB, | |
816 | * 2nd page turns out to be skipped (i.e. no new bytes written to the | |
817 | * page), the overall encoding rate will be 8KB / 2KB = 4, which has the | |
818 | * skipped page included. In this way, the encoding rate can tell if the | |
819 | * guest page is good for xbzrle encoding. | |
820 | */ | |
821 | xbzrle_counters.pages++; | |
56e93d26 JQ |
822 | prev_cached_page = get_cached_data(XBZRLE.cache, current_addr); |
823 | ||
824 | /* save current buffer into memory */ | |
825 | memcpy(XBZRLE.current_buf, *current_data, TARGET_PAGE_SIZE); | |
826 | ||
827 | /* XBZRLE encoding (if there is no overflow) */ | |
04ffce13 | 828 | encoded_len = xbzrle_encode_buffer_func(prev_cached_page, XBZRLE.current_buf, |
829 | TARGET_PAGE_SIZE, XBZRLE.encoded_buf, | |
830 | TARGET_PAGE_SIZE); | |
ca353803 WY |
831 | |
832 | /* | |
833 | * Update the cache contents, so that it corresponds to the data | |
834 | * sent, in all cases except where we skip the page. | |
835 | */ | |
05931ec5 | 836 | if (!rs->last_stage && encoded_len != 0) { |
ca353803 WY |
837 | memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); |
838 | /* | |
839 | * In the case where we couldn't compress, ensure that the caller | |
840 | * sends the data from the cache, since the guest might have | |
841 | * changed the RAM since we copied it. | |
842 | */ | |
843 | *current_data = prev_cached_page; | |
844 | } | |
845 | ||
56e93d26 | 846 | if (encoded_len == 0) { |
55c4446b | 847 | trace_save_xbzrle_page_skipping(); |
56e93d26 JQ |
848 | return 0; |
849 | } else if (encoded_len == -1) { | |
55c4446b | 850 | trace_save_xbzrle_page_overflow(); |
9360447d | 851 | xbzrle_counters.overflow++; |
e460a4b1 | 852 | xbzrle_counters.bytes += TARGET_PAGE_SIZE; |
56e93d26 JQ |
853 | return -1; |
854 | } | |
855 | ||
56e93d26 | 856 | /* Send XBZRLE based compressed page */ |
37502df3 | 857 | bytes_xbzrle = save_page_header(pss, pss->pss_channel, block, |
204b88b8 | 858 | offset | RAM_SAVE_FLAG_XBZRLE); |
61717ea9 PX |
859 | qemu_put_byte(file, ENCODING_FLAG_XBZRLE); |
860 | qemu_put_be16(file, encoded_len); | |
861 | qemu_put_buffer(file, XBZRLE.encoded_buf, encoded_len); | |
56e93d26 | 862 | bytes_xbzrle += encoded_len + 1 + 2; |
e460a4b1 WW |
863 | /* |
864 | * Like compressed_size (please see update_compress_thread_counts), | |
865 | * the xbzrle encoded bytes don't count the 8 byte header with | |
866 | * RAM_SAVE_FLAG_CONTINUE. | |
867 | */ | |
868 | xbzrle_counters.bytes += bytes_xbzrle - 8; | |
4c2d0f6d | 869 | ram_transferred_add(bytes_xbzrle); |
56e93d26 JQ |
870 | |
871 | return 1; | |
872 | } | |
873 | ||
3d0684b2 | 874 | /** |
d9e474ea | 875 | * pss_find_next_dirty: find the next dirty page of current ramblock |
f3f491fc | 876 | * |
d9e474ea PX |
877 | * This function updates pss->page to point to the next dirty page index |
878 | * within the ramblock to migrate, or the end of ramblock when nothing | |
879 | * found. Note that when pss->host_page_sending==true it means we're | |
880 | * during sending a host page, so we won't look for dirty page that is | |
881 | * outside the host page boundary. | |
3d0684b2 | 882 | * |
d9e474ea | 883 | * @pss: the current page search status |
f3f491fc | 884 | */ |
d9e474ea | 885 | static void pss_find_next_dirty(PageSearchStatus *pss) |
56e93d26 | 886 | { |
d9e474ea | 887 | RAMBlock *rb = pss->block; |
6b6712ef JQ |
888 | unsigned long size = rb->used_length >> TARGET_PAGE_BITS; |
889 | unsigned long *bitmap = rb->bmap; | |
56e93d26 | 890 | |
fbd162e6 | 891 | if (ramblock_is_ignored(rb)) { |
d9e474ea PX |
892 | /* Points directly to the end, so we know no dirty page */ |
893 | pss->page = size; | |
894 | return; | |
895 | } | |
896 | ||
897 | /* | |
898 | * If during sending a host page, only look for dirty pages within the | |
899 | * current host page being send. | |
900 | */ | |
901 | if (pss->host_page_sending) { | |
902 | assert(pss->host_page_end); | |
903 | size = MIN(size, pss->host_page_end); | |
b895de50 CLG |
904 | } |
905 | ||
d9e474ea | 906 | pss->page = find_next_bit(bitmap, size, pss->page); |
56e93d26 JQ |
907 | } |
908 | ||
1230a25f | 909 | static void migration_clear_memory_region_dirty_bitmap(RAMBlock *rb, |
3143577d WW |
910 | unsigned long page) |
911 | { | |
912 | uint8_t shift; | |
913 | hwaddr size, start; | |
914 | ||
915 | if (!rb->clear_bmap || !clear_bmap_test_and_clear(rb, page)) { | |
916 | return; | |
917 | } | |
918 | ||
919 | shift = rb->clear_bmap_shift; | |
920 | /* | |
921 | * CLEAR_BITMAP_SHIFT_MIN should always guarantee this... this | |
922 | * can make things easier sometimes since then start address | |
923 | * of the small chunk will always be 64 pages aligned so the | |
924 | * bitmap will always be aligned to unsigned long. We should | |
925 | * even be able to remove this restriction but I'm simply | |
926 | * keeping it. | |
927 | */ | |
928 | assert(shift >= 6); | |
929 | ||
930 | size = 1ULL << (TARGET_PAGE_BITS + shift); | |
7648297d | 931 | start = QEMU_ALIGN_DOWN((ram_addr_t)page << TARGET_PAGE_BITS, size); |
3143577d WW |
932 | trace_migration_bitmap_clear_dirty(rb->idstr, start, size, page); |
933 | memory_region_clear_dirty_bitmap(rb->mr, start, size); | |
934 | } | |
935 | ||
936 | static void | |
1230a25f | 937 | migration_clear_memory_region_dirty_bitmap_range(RAMBlock *rb, |
3143577d WW |
938 | unsigned long start, |
939 | unsigned long npages) | |
940 | { | |
941 | unsigned long i, chunk_pages = 1UL << rb->clear_bmap_shift; | |
942 | unsigned long chunk_start = QEMU_ALIGN_DOWN(start, chunk_pages); | |
943 | unsigned long chunk_end = QEMU_ALIGN_UP(start + npages, chunk_pages); | |
944 | ||
945 | /* | |
946 | * Clear pages from start to start + npages - 1, so the end boundary is | |
947 | * exclusive. | |
948 | */ | |
949 | for (i = chunk_start; i < chunk_end; i += chunk_pages) { | |
1230a25f | 950 | migration_clear_memory_region_dirty_bitmap(rb, i); |
3143577d WW |
951 | } |
952 | } | |
953 | ||
a6a83cef RL |
954 | /* |
955 | * colo_bitmap_find_diry:find contiguous dirty pages from start | |
956 | * | |
957 | * Returns the page offset within memory region of the start of the contiguout | |
958 | * dirty page | |
959 | * | |
960 | * @rs: current RAM state | |
961 | * @rb: RAMBlock where to search for dirty pages | |
962 | * @start: page where we start the search | |
963 | * @num: the number of contiguous dirty pages | |
964 | */ | |
965 | static inline | |
966 | unsigned long colo_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, | |
967 | unsigned long start, unsigned long *num) | |
968 | { | |
969 | unsigned long size = rb->used_length >> TARGET_PAGE_BITS; | |
970 | unsigned long *bitmap = rb->bmap; | |
971 | unsigned long first, next; | |
972 | ||
973 | *num = 0; | |
974 | ||
975 | if (ramblock_is_ignored(rb)) { | |
976 | return size; | |
977 | } | |
978 | ||
979 | first = find_next_bit(bitmap, size, start); | |
980 | if (first >= size) { | |
981 | return first; | |
982 | } | |
983 | next = find_next_zero_bit(bitmap, size, first + 1); | |
984 | assert(next >= first); | |
985 | *num = next - first; | |
986 | return first; | |
987 | } | |
988 | ||
06b10688 | 989 | static inline bool migration_bitmap_clear_dirty(RAMState *rs, |
f20e2865 JQ |
990 | RAMBlock *rb, |
991 | unsigned long page) | |
a82d593b DDAG |
992 | { |
993 | bool ret; | |
a82d593b | 994 | |
002cad6b PX |
995 | /* |
996 | * Clear dirty bitmap if needed. This _must_ be called before we | |
997 | * send any of the page in the chunk because we need to make sure | |
998 | * we can capture further page content changes when we sync dirty | |
999 | * log the next time. So as long as we are going to send any of | |
1000 | * the page in the chunk we clear the remote dirty bitmap for all. | |
1001 | * Clearing it earlier won't be a problem, but too late will. | |
1002 | */ | |
1230a25f | 1003 | migration_clear_memory_region_dirty_bitmap(rb, page); |
002cad6b | 1004 | |
6b6712ef | 1005 | ret = test_and_clear_bit(page, rb->bmap); |
a82d593b | 1006 | if (ret) { |
0d8ec885 | 1007 | rs->migration_dirty_pages--; |
a82d593b | 1008 | } |
386a907b | 1009 | |
a82d593b DDAG |
1010 | return ret; |
1011 | } | |
1012 | ||
be39b4cd DH |
1013 | static void dirty_bitmap_clear_section(MemoryRegionSection *section, |
1014 | void *opaque) | |
1015 | { | |
1016 | const hwaddr offset = section->offset_within_region; | |
1017 | const hwaddr size = int128_get64(section->size); | |
1018 | const unsigned long start = offset >> TARGET_PAGE_BITS; | |
1019 | const unsigned long npages = size >> TARGET_PAGE_BITS; | |
1020 | RAMBlock *rb = section->mr->ram_block; | |
1021 | uint64_t *cleared_bits = opaque; | |
1022 | ||
1023 | /* | |
1024 | * We don't grab ram_state->bitmap_mutex because we expect to run | |
1025 | * only when starting migration or during postcopy recovery where | |
1026 | * we don't have concurrent access. | |
1027 | */ | |
1028 | if (!migration_in_postcopy() && !migrate_background_snapshot()) { | |
1029 | migration_clear_memory_region_dirty_bitmap_range(rb, start, npages); | |
1030 | } | |
1031 | *cleared_bits += bitmap_count_one_with_offset(rb->bmap, start, npages); | |
1032 | bitmap_clear(rb->bmap, start, npages); | |
1033 | } | |
1034 | ||
1035 | /* | |
1036 | * Exclude all dirty pages from migration that fall into a discarded range as | |
1037 | * managed by a RamDiscardManager responsible for the mapped memory region of | |
1038 | * the RAMBlock. Clear the corresponding bits in the dirty bitmaps. | |
1039 | * | |
1040 | * Discarded pages ("logically unplugged") have undefined content and must | |
1041 | * not get migrated, because even reading these pages for migration might | |
1042 | * result in undesired behavior. | |
1043 | * | |
1044 | * Returns the number of cleared bits in the RAMBlock dirty bitmap. | |
1045 | * | |
1046 | * Note: The result is only stable while migrating (precopy/postcopy). | |
1047 | */ | |
1048 | static uint64_t ramblock_dirty_bitmap_clear_discarded_pages(RAMBlock *rb) | |
1049 | { | |
1050 | uint64_t cleared_bits = 0; | |
1051 | ||
1052 | if (rb->mr && rb->bmap && memory_region_has_ram_discard_manager(rb->mr)) { | |
1053 | RamDiscardManager *rdm = memory_region_get_ram_discard_manager(rb->mr); | |
1054 | MemoryRegionSection section = { | |
1055 | .mr = rb->mr, | |
1056 | .offset_within_region = 0, | |
1057 | .size = int128_make64(qemu_ram_get_used_length(rb)), | |
1058 | }; | |
1059 | ||
1060 | ram_discard_manager_replay_discarded(rdm, §ion, | |
1061 | dirty_bitmap_clear_section, | |
1062 | &cleared_bits); | |
1063 | } | |
1064 | return cleared_bits; | |
1065 | } | |
1066 | ||
9470c5e0 DH |
1067 | /* |
1068 | * Check if a host-page aligned page falls into a discarded range as managed by | |
1069 | * a RamDiscardManager responsible for the mapped memory region of the RAMBlock. | |
1070 | * | |
1071 | * Note: The result is only stable while migrating (precopy/postcopy). | |
1072 | */ | |
1073 | bool ramblock_page_is_discarded(RAMBlock *rb, ram_addr_t start) | |
1074 | { | |
1075 | if (rb->mr && memory_region_has_ram_discard_manager(rb->mr)) { | |
1076 | RamDiscardManager *rdm = memory_region_get_ram_discard_manager(rb->mr); | |
1077 | MemoryRegionSection section = { | |
1078 | .mr = rb->mr, | |
1079 | .offset_within_region = start, | |
1080 | .size = int128_make64(qemu_ram_pagesize(rb)), | |
1081 | }; | |
1082 | ||
1083 | return !ram_discard_manager_is_populated(rdm, §ion); | |
1084 | } | |
1085 | return false; | |
1086 | } | |
1087 | ||
267691b6 | 1088 | /* Called with RCU critical section */ |
7a3e9571 | 1089 | static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb) |
56e93d26 | 1090 | { |
fb613580 KZ |
1091 | uint64_t new_dirty_pages = |
1092 | cpu_physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length); | |
1093 | ||
1094 | rs->migration_dirty_pages += new_dirty_pages; | |
1095 | rs->num_dirty_pages_period += new_dirty_pages; | |
56e93d26 JQ |
1096 | } |
1097 | ||
3d0684b2 JQ |
1098 | /** |
1099 | * ram_pagesize_summary: calculate all the pagesizes of a VM | |
1100 | * | |
1101 | * Returns a summary bitmap of the page sizes of all RAMBlocks | |
1102 | * | |
1103 | * For VMs with just normal pages this is equivalent to the host page | |
1104 | * size. If it's got some huge pages then it's the OR of all the | |
1105 | * different page sizes. | |
e8ca1db2 DDAG |
1106 | */ |
1107 | uint64_t ram_pagesize_summary(void) | |
1108 | { | |
1109 | RAMBlock *block; | |
1110 | uint64_t summary = 0; | |
1111 | ||
fbd162e6 | 1112 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
e8ca1db2 DDAG |
1113 | summary |= block->page_size; |
1114 | } | |
1115 | ||
1116 | return summary; | |
1117 | } | |
1118 | ||
aecbfe9c XG |
1119 | uint64_t ram_get_total_transferred_pages(void) |
1120 | { | |
abce5fa1 JQ |
1121 | return stat64_get(&ram_counters.normal) + |
1122 | stat64_get(&ram_counters.duplicate) + | |
23b7576d | 1123 | compression_counters.pages + xbzrle_counters.pages; |
aecbfe9c XG |
1124 | } |
1125 | ||
b734035b XG |
1126 | static void migration_update_rates(RAMState *rs, int64_t end_time) |
1127 | { | |
be8b02ed | 1128 | uint64_t page_count = rs->target_page_count - rs->target_page_count_prev; |
76e03000 | 1129 | double compressed_size; |
b734035b XG |
1130 | |
1131 | /* calculate period counters */ | |
1132 | ram_counters.dirty_pages_rate = rs->num_dirty_pages_period * 1000 | |
1133 | / (end_time - rs->time_last_bitmap_sync); | |
1134 | ||
be8b02ed | 1135 | if (!page_count) { |
b734035b XG |
1136 | return; |
1137 | } | |
1138 | ||
1139 | if (migrate_use_xbzrle()) { | |
e460a4b1 WW |
1140 | double encoded_size, unencoded_size; |
1141 | ||
b734035b | 1142 | xbzrle_counters.cache_miss_rate = (double)(xbzrle_counters.cache_miss - |
be8b02ed | 1143 | rs->xbzrle_cache_miss_prev) / page_count; |
b734035b | 1144 | rs->xbzrle_cache_miss_prev = xbzrle_counters.cache_miss; |
e460a4b1 WW |
1145 | unencoded_size = (xbzrle_counters.pages - rs->xbzrle_pages_prev) * |
1146 | TARGET_PAGE_SIZE; | |
1147 | encoded_size = xbzrle_counters.bytes - rs->xbzrle_bytes_prev; | |
92271402 | 1148 | if (xbzrle_counters.pages == rs->xbzrle_pages_prev || !encoded_size) { |
e460a4b1 | 1149 | xbzrle_counters.encoding_rate = 0; |
e460a4b1 WW |
1150 | } else { |
1151 | xbzrle_counters.encoding_rate = unencoded_size / encoded_size; | |
1152 | } | |
1153 | rs->xbzrle_pages_prev = xbzrle_counters.pages; | |
1154 | rs->xbzrle_bytes_prev = xbzrle_counters.bytes; | |
b734035b | 1155 | } |
76e03000 XG |
1156 | |
1157 | if (migrate_use_compression()) { | |
1158 | compression_counters.busy_rate = (double)(compression_counters.busy - | |
1159 | rs->compress_thread_busy_prev) / page_count; | |
1160 | rs->compress_thread_busy_prev = compression_counters.busy; | |
1161 | ||
1162 | compressed_size = compression_counters.compressed_size - | |
1163 | rs->compressed_size_prev; | |
1164 | if (compressed_size) { | |
1165 | double uncompressed_size = (compression_counters.pages - | |
1166 | rs->compress_pages_prev) * TARGET_PAGE_SIZE; | |
1167 | ||
1168 | /* Compression-Ratio = Uncompressed-size / Compressed-size */ | |
1169 | compression_counters.compression_rate = | |
1170 | uncompressed_size / compressed_size; | |
1171 | ||
1172 | rs->compress_pages_prev = compression_counters.pages; | |
1173 | rs->compressed_size_prev = compression_counters.compressed_size; | |
1174 | } | |
1175 | } | |
b734035b XG |
1176 | } |
1177 | ||
dc14a470 KZ |
1178 | static void migration_trigger_throttle(RAMState *rs) |
1179 | { | |
1180 | MigrationState *s = migrate_get_current(); | |
1181 | uint64_t threshold = s->parameters.throttle_trigger_threshold; | |
23b7576d | 1182 | uint64_t bytes_xfer_period = |
abce5fa1 | 1183 | stat64_get(&ram_counters.transferred) - rs->bytes_xfer_prev; |
dc14a470 KZ |
1184 | uint64_t bytes_dirty_period = rs->num_dirty_pages_period * TARGET_PAGE_SIZE; |
1185 | uint64_t bytes_dirty_threshold = bytes_xfer_period * threshold / 100; | |
1186 | ||
1187 | /* During block migration the auto-converge logic incorrectly detects | |
1188 | * that ram migration makes no progress. Avoid this by disabling the | |
1189 | * throttling logic during the bulk phase of block migration. */ | |
1190 | if (migrate_auto_converge() && !blk_mig_bulk_active()) { | |
1191 | /* The following detection logic can be refined later. For now: | |
1192 | Check to see if the ratio between dirtied bytes and the approx. | |
1193 | amount of bytes that just got transferred since the last time | |
1194 | we were in this routine reaches the threshold. If that happens | |
1195 | twice, start or increase throttling. */ | |
1196 | ||
1197 | if ((bytes_dirty_period > bytes_dirty_threshold) && | |
1198 | (++rs->dirty_rate_high_cnt >= 2)) { | |
1199 | trace_migration_throttle(); | |
1200 | rs->dirty_rate_high_cnt = 0; | |
cbbf8182 KZ |
1201 | mig_throttle_guest_down(bytes_dirty_period, |
1202 | bytes_dirty_threshold); | |
dc14a470 KZ |
1203 | } |
1204 | } | |
1205 | } | |
1206 | ||
8d820d6f | 1207 | static void migration_bitmap_sync(RAMState *rs) |
56e93d26 JQ |
1208 | { |
1209 | RAMBlock *block; | |
56e93d26 | 1210 | int64_t end_time; |
56e93d26 | 1211 | |
9360447d | 1212 | ram_counters.dirty_sync_count++; |
56e93d26 | 1213 | |
f664da80 JQ |
1214 | if (!rs->time_last_bitmap_sync) { |
1215 | rs->time_last_bitmap_sync = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); | |
56e93d26 JQ |
1216 | } |
1217 | ||
1218 | trace_migration_bitmap_sync_start(); | |
9c1f8f44 | 1219 | memory_global_dirty_log_sync(); |
56e93d26 | 1220 | |
108cfae0 | 1221 | qemu_mutex_lock(&rs->bitmap_mutex); |
89ac5a1d DDAG |
1222 | WITH_RCU_READ_LOCK_GUARD() { |
1223 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
1224 | ramblock_sync_dirty_bitmap(rs, block); | |
1225 | } | |
1226 | ram_counters.remaining = ram_bytes_remaining(); | |
56e93d26 | 1227 | } |
108cfae0 | 1228 | qemu_mutex_unlock(&rs->bitmap_mutex); |
56e93d26 | 1229 | |
9458a9a1 | 1230 | memory_global_after_dirty_log_sync(); |
a66cd90c | 1231 | trace_migration_bitmap_sync_end(rs->num_dirty_pages_period); |
1ffb5dfd | 1232 | |
56e93d26 JQ |
1233 | end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); |
1234 | ||
1235 | /* more than 1 second = 1000 millisecons */ | |
f664da80 | 1236 | if (end_time > rs->time_last_bitmap_sync + 1000) { |
dc14a470 | 1237 | migration_trigger_throttle(rs); |
070afca2 | 1238 | |
b734035b XG |
1239 | migration_update_rates(rs, end_time); |
1240 | ||
be8b02ed | 1241 | rs->target_page_count_prev = rs->target_page_count; |
d693c6f1 FF |
1242 | |
1243 | /* reset period counters */ | |
f664da80 | 1244 | rs->time_last_bitmap_sync = end_time; |
a66cd90c | 1245 | rs->num_dirty_pages_period = 0; |
abce5fa1 | 1246 | rs->bytes_xfer_prev = stat64_get(&ram_counters.transferred); |
56e93d26 | 1247 | } |
4addcd4f | 1248 | if (migrate_use_events()) { |
3ab72385 | 1249 | qapi_event_send_migration_pass(ram_counters.dirty_sync_count); |
4addcd4f | 1250 | } |
56e93d26 JQ |
1251 | } |
1252 | ||
bd227060 WW |
1253 | static void migration_bitmap_sync_precopy(RAMState *rs) |
1254 | { | |
1255 | Error *local_err = NULL; | |
1256 | ||
1257 | /* | |
1258 | * The current notifier usage is just an optimization to migration, so we | |
1259 | * don't stop the normal migration process in the error case. | |
1260 | */ | |
1261 | if (precopy_notify(PRECOPY_NOTIFY_BEFORE_BITMAP_SYNC, &local_err)) { | |
1262 | error_report_err(local_err); | |
b4a1733c | 1263 | local_err = NULL; |
bd227060 WW |
1264 | } |
1265 | ||
1266 | migration_bitmap_sync(rs); | |
1267 | ||
1268 | if (precopy_notify(PRECOPY_NOTIFY_AFTER_BITMAP_SYNC, &local_err)) { | |
1269 | error_report_err(local_err); | |
1270 | } | |
1271 | } | |
1272 | ||
a4dbaf8e | 1273 | void ram_release_page(const char *rbname, uint64_t offset) |
47fe16ff JQ |
1274 | { |
1275 | if (!migrate_release_ram() || !migration_in_postcopy()) { | |
1276 | return; | |
1277 | } | |
1278 | ||
1279 | ram_discard_range(rbname, offset, TARGET_PAGE_SIZE); | |
1280 | } | |
1281 | ||
6c97ec5f XG |
1282 | /** |
1283 | * save_zero_page_to_file: send the zero page to the file | |
1284 | * | |
1285 | * Returns the size of data written to the file, 0 means the page is not | |
1286 | * a zero page | |
1287 | * | |
ec6f3ab9 | 1288 | * @pss: current PSS channel |
6c97ec5f XG |
1289 | * @block: block that contains the page we want to send |
1290 | * @offset: offset inside the block for the page | |
1291 | */ | |
37502df3 | 1292 | static int save_zero_page_to_file(PageSearchStatus *pss, QEMUFile *file, |
6c97ec5f XG |
1293 | RAMBlock *block, ram_addr_t offset) |
1294 | { | |
1295 | uint8_t *p = block->host + offset; | |
1296 | int len = 0; | |
1297 | ||
bad452a7 | 1298 | if (buffer_is_zero(p, TARGET_PAGE_SIZE)) { |
37502df3 | 1299 | len += save_page_header(pss, file, block, offset | RAM_SAVE_FLAG_ZERO); |
6c97ec5f XG |
1300 | qemu_put_byte(file, 0); |
1301 | len += 1; | |
47fe16ff | 1302 | ram_release_page(block->idstr, offset); |
6c97ec5f XG |
1303 | } |
1304 | return len; | |
1305 | } | |
1306 | ||
56e93d26 | 1307 | /** |
3d0684b2 | 1308 | * save_zero_page: send the zero page to the stream |
56e93d26 | 1309 | * |
3d0684b2 | 1310 | * Returns the number of pages written. |
56e93d26 | 1311 | * |
ec6f3ab9 | 1312 | * @pss: current PSS channel |
56e93d26 JQ |
1313 | * @block: block that contains the page we want to send |
1314 | * @offset: offset inside the block for the page | |
56e93d26 | 1315 | */ |
37502df3 | 1316 | static int save_zero_page(PageSearchStatus *pss, QEMUFile *f, RAMBlock *block, |
61717ea9 | 1317 | ram_addr_t offset) |
56e93d26 | 1318 | { |
37502df3 | 1319 | int len = save_zero_page_to_file(pss, f, block, offset); |
56e93d26 | 1320 | |
6c97ec5f | 1321 | if (len) { |
abce5fa1 | 1322 | stat64_add(&ram_counters.duplicate, 1); |
4c2d0f6d | 1323 | ram_transferred_add(len); |
6c97ec5f | 1324 | return 1; |
56e93d26 | 1325 | } |
6c97ec5f | 1326 | return -1; |
56e93d26 JQ |
1327 | } |
1328 | ||
059ff0fb XG |
1329 | /* |
1330 | * @pages: the number of pages written by the control path, | |
1331 | * < 0 - error | |
1332 | * > 0 - number of pages written | |
1333 | * | |
1334 | * Return true if the pages has been saved, otherwise false is returned. | |
1335 | */ | |
61717ea9 PX |
1336 | static bool control_save_page(PageSearchStatus *pss, RAMBlock *block, |
1337 | ram_addr_t offset, int *pages) | |
059ff0fb XG |
1338 | { |
1339 | uint64_t bytes_xmit = 0; | |
1340 | int ret; | |
1341 | ||
1342 | *pages = -1; | |
61717ea9 PX |
1343 | ret = ram_control_save_page(pss->pss_channel, block->offset, offset, |
1344 | TARGET_PAGE_SIZE, &bytes_xmit); | |
059ff0fb XG |
1345 | if (ret == RAM_SAVE_CONTROL_NOT_SUPP) { |
1346 | return false; | |
1347 | } | |
1348 | ||
1349 | if (bytes_xmit) { | |
4c2d0f6d | 1350 | ram_transferred_add(bytes_xmit); |
059ff0fb XG |
1351 | *pages = 1; |
1352 | } | |
1353 | ||
1354 | if (ret == RAM_SAVE_CONTROL_DELAYED) { | |
1355 | return true; | |
1356 | } | |
1357 | ||
1358 | if (bytes_xmit > 0) { | |
abce5fa1 | 1359 | stat64_add(&ram_counters.normal, 1); |
059ff0fb | 1360 | } else if (bytes_xmit == 0) { |
abce5fa1 | 1361 | stat64_add(&ram_counters.duplicate, 1); |
059ff0fb XG |
1362 | } |
1363 | ||
1364 | return true; | |
1365 | } | |
1366 | ||
65dacaa0 XG |
1367 | /* |
1368 | * directly send the page to the stream | |
1369 | * | |
1370 | * Returns the number of pages written. | |
1371 | * | |
ec6f3ab9 | 1372 | * @pss: current PSS channel |
65dacaa0 XG |
1373 | * @block: block that contains the page we want to send |
1374 | * @offset: offset inside the block for the page | |
1375 | * @buf: the page to be sent | |
1376 | * @async: send to page asyncly | |
1377 | */ | |
ec6f3ab9 | 1378 | static int save_normal_page(PageSearchStatus *pss, RAMBlock *block, |
61717ea9 | 1379 | ram_addr_t offset, uint8_t *buf, bool async) |
65dacaa0 | 1380 | { |
ec6f3ab9 PX |
1381 | QEMUFile *file = pss->pss_channel; |
1382 | ||
37502df3 | 1383 | ram_transferred_add(save_page_header(pss, pss->pss_channel, block, |
4c2d0f6d | 1384 | offset | RAM_SAVE_FLAG_PAGE)); |
65dacaa0 | 1385 | if (async) { |
61717ea9 | 1386 | qemu_put_buffer_async(file, buf, TARGET_PAGE_SIZE, |
f912ec5b | 1387 | migrate_release_ram() && |
65dacaa0 XG |
1388 | migration_in_postcopy()); |
1389 | } else { | |
61717ea9 | 1390 | qemu_put_buffer(file, buf, TARGET_PAGE_SIZE); |
65dacaa0 | 1391 | } |
4c2d0f6d | 1392 | ram_transferred_add(TARGET_PAGE_SIZE); |
abce5fa1 | 1393 | stat64_add(&ram_counters.normal, 1); |
65dacaa0 XG |
1394 | return 1; |
1395 | } | |
1396 | ||
56e93d26 | 1397 | /** |
3d0684b2 | 1398 | * ram_save_page: send the given page to the stream |
56e93d26 | 1399 | * |
3d0684b2 | 1400 | * Returns the number of pages written. |
3fd3c4b3 DDAG |
1401 | * < 0 - error |
1402 | * >=0 - Number of pages written - this might legally be 0 | |
1403 | * if xbzrle noticed the page was the same. | |
56e93d26 | 1404 | * |
6f37bb8b | 1405 | * @rs: current RAM state |
56e93d26 JQ |
1406 | * @block: block that contains the page we want to send |
1407 | * @offset: offset inside the block for the page | |
56e93d26 | 1408 | */ |
05931ec5 | 1409 | static int ram_save_page(RAMState *rs, PageSearchStatus *pss) |
56e93d26 JQ |
1410 | { |
1411 | int pages = -1; | |
56e93d26 | 1412 | uint8_t *p; |
56e93d26 | 1413 | bool send_async = true; |
a08f6890 | 1414 | RAMBlock *block = pss->block; |
8bba004c | 1415 | ram_addr_t offset = ((ram_addr_t)pss->page) << TARGET_PAGE_BITS; |
059ff0fb | 1416 | ram_addr_t current_addr = block->offset + offset; |
56e93d26 | 1417 | |
2f68e399 | 1418 | p = block->host + offset; |
1db9d8e5 | 1419 | trace_ram_save_page(block->idstr, (uint64_t)offset, p); |
56e93d26 | 1420 | |
56e93d26 | 1421 | XBZRLE_cache_lock(); |
1a373522 | 1422 | if (rs->xbzrle_enabled && !migration_in_postcopy()) { |
ec6f3ab9 | 1423 | pages = save_xbzrle_page(rs, pss, &p, current_addr, |
61717ea9 | 1424 | block, offset); |
05931ec5 | 1425 | if (!rs->last_stage) { |
059ff0fb XG |
1426 | /* Can't send this cached data async, since the cache page |
1427 | * might get updated before it gets to the wire | |
56e93d26 | 1428 | */ |
059ff0fb | 1429 | send_async = false; |
56e93d26 JQ |
1430 | } |
1431 | } | |
1432 | ||
1433 | /* XBZRLE overflow or normal page */ | |
1434 | if (pages == -1) { | |
ec6f3ab9 | 1435 | pages = save_normal_page(pss, block, offset, p, send_async); |
56e93d26 JQ |
1436 | } |
1437 | ||
1438 | XBZRLE_cache_unlock(); | |
1439 | ||
1440 | return pages; | |
1441 | } | |
1442 | ||
61717ea9 | 1443 | static int ram_save_multifd_page(QEMUFile *file, RAMBlock *block, |
b9ee2f7d JQ |
1444 | ram_addr_t offset) |
1445 | { | |
61717ea9 | 1446 | if (multifd_queue_page(file, block, offset) < 0) { |
713f762a IR |
1447 | return -1; |
1448 | } | |
abce5fa1 | 1449 | stat64_add(&ram_counters.normal, 1); |
b9ee2f7d JQ |
1450 | |
1451 | return 1; | |
1452 | } | |
1453 | ||
5e5fdcff | 1454 | static bool do_compress_ram_page(QEMUFile *f, z_stream *stream, RAMBlock *block, |
6ef3771c | 1455 | ram_addr_t offset, uint8_t *source_buf) |
56e93d26 | 1456 | { |
53518d94 | 1457 | RAMState *rs = ram_state; |
ec6f3ab9 | 1458 | PageSearchStatus *pss = &rs->pss[RAM_CHANNEL_PRECOPY]; |
20d549cb | 1459 | uint8_t *p = block->host + offset; |
6ef3771c | 1460 | int ret; |
56e93d26 | 1461 | |
37502df3 | 1462 | if (save_zero_page_to_file(pss, f, block, offset)) { |
e7f2e190 | 1463 | return true; |
5e5fdcff XG |
1464 | } |
1465 | ||
37502df3 | 1466 | save_page_header(pss, f, block, offset | RAM_SAVE_FLAG_COMPRESS_PAGE); |
34ab9e97 XG |
1467 | |
1468 | /* | |
1469 | * copy it to a internal buffer to avoid it being modified by VM | |
1470 | * so that we can catch up the error during compression and | |
1471 | * decompression | |
1472 | */ | |
1473 | memcpy(source_buf, p, TARGET_PAGE_SIZE); | |
6ef3771c XG |
1474 | ret = qemu_put_compression_data(f, stream, source_buf, TARGET_PAGE_SIZE); |
1475 | if (ret < 0) { | |
1476 | qemu_file_set_error(migrate_get_current()->to_dst_file, ret); | |
b3be2896 | 1477 | error_report("compressed data failed!"); |
b3be2896 | 1478 | } |
e7f2e190 | 1479 | return false; |
5e5fdcff XG |
1480 | } |
1481 | ||
1482 | static void | |
1483 | update_compress_thread_counts(const CompressParam *param, int bytes_xmit) | |
1484 | { | |
4c2d0f6d | 1485 | ram_transferred_add(bytes_xmit); |
76e03000 | 1486 | |
5e5fdcff | 1487 | if (param->zero_page) { |
abce5fa1 | 1488 | stat64_add(&ram_counters.duplicate, 1); |
76e03000 | 1489 | return; |
5e5fdcff | 1490 | } |
76e03000 XG |
1491 | |
1492 | /* 8 means a header with RAM_SAVE_FLAG_CONTINUE. */ | |
1493 | compression_counters.compressed_size += bytes_xmit - 8; | |
1494 | compression_counters.pages++; | |
56e93d26 JQ |
1495 | } |
1496 | ||
32b05495 XG |
1497 | static bool save_page_use_compression(RAMState *rs); |
1498 | ||
ce25d337 | 1499 | static void flush_compressed_data(RAMState *rs) |
56e93d26 | 1500 | { |
eaa238ab | 1501 | MigrationState *ms = migrate_get_current(); |
56e93d26 JQ |
1502 | int idx, len, thread_count; |
1503 | ||
32b05495 | 1504 | if (!save_page_use_compression(rs)) { |
56e93d26 JQ |
1505 | return; |
1506 | } | |
1507 | thread_count = migrate_compress_threads(); | |
a7a9a88f | 1508 | |
0d9f9a5c | 1509 | qemu_mutex_lock(&comp_done_lock); |
56e93d26 | 1510 | for (idx = 0; idx < thread_count; idx++) { |
a7a9a88f | 1511 | while (!comp_param[idx].done) { |
0d9f9a5c | 1512 | qemu_cond_wait(&comp_done_cond, &comp_done_lock); |
56e93d26 | 1513 | } |
a7a9a88f | 1514 | } |
0d9f9a5c | 1515 | qemu_mutex_unlock(&comp_done_lock); |
a7a9a88f LL |
1516 | |
1517 | for (idx = 0; idx < thread_count; idx++) { | |
1518 | qemu_mutex_lock(&comp_param[idx].mutex); | |
90e56fb4 | 1519 | if (!comp_param[idx].quit) { |
eaa238ab | 1520 | len = qemu_put_qemu_file(ms->to_dst_file, comp_param[idx].file); |
5e5fdcff XG |
1521 | /* |
1522 | * it's safe to fetch zero_page without holding comp_done_lock | |
1523 | * as there is no further request submitted to the thread, | |
1524 | * i.e, the thread should be waiting for a request at this point. | |
1525 | */ | |
1526 | update_compress_thread_counts(&comp_param[idx], len); | |
56e93d26 | 1527 | } |
a7a9a88f | 1528 | qemu_mutex_unlock(&comp_param[idx].mutex); |
56e93d26 JQ |
1529 | } |
1530 | } | |
1531 | ||
1532 | static inline void set_compress_params(CompressParam *param, RAMBlock *block, | |
1533 | ram_addr_t offset) | |
1534 | { | |
1535 | param->block = block; | |
1536 | param->offset = offset; | |
1537 | } | |
1538 | ||
eaa238ab | 1539 | static int compress_page_with_multi_thread(RAMBlock *block, ram_addr_t offset) |
56e93d26 JQ |
1540 | { |
1541 | int idx, thread_count, bytes_xmit = -1, pages = -1; | |
1d58872a | 1542 | bool wait = migrate_compress_wait_thread(); |
eaa238ab | 1543 | MigrationState *ms = migrate_get_current(); |
56e93d26 JQ |
1544 | |
1545 | thread_count = migrate_compress_threads(); | |
0d9f9a5c | 1546 | qemu_mutex_lock(&comp_done_lock); |
1d58872a XG |
1547 | retry: |
1548 | for (idx = 0; idx < thread_count; idx++) { | |
1549 | if (comp_param[idx].done) { | |
1550 | comp_param[idx].done = false; | |
eaa238ab PX |
1551 | bytes_xmit = qemu_put_qemu_file(ms->to_dst_file, |
1552 | comp_param[idx].file); | |
1d58872a XG |
1553 | qemu_mutex_lock(&comp_param[idx].mutex); |
1554 | set_compress_params(&comp_param[idx], block, offset); | |
1555 | qemu_cond_signal(&comp_param[idx].cond); | |
1556 | qemu_mutex_unlock(&comp_param[idx].mutex); | |
1557 | pages = 1; | |
5e5fdcff | 1558 | update_compress_thread_counts(&comp_param[idx], bytes_xmit); |
56e93d26 | 1559 | break; |
56e93d26 JQ |
1560 | } |
1561 | } | |
1d58872a XG |
1562 | |
1563 | /* | |
1564 | * wait for the free thread if the user specifies 'compress-wait-thread', | |
1565 | * otherwise we will post the page out in the main thread as normal page. | |
1566 | */ | |
1567 | if (pages < 0 && wait) { | |
1568 | qemu_cond_wait(&comp_done_cond, &comp_done_lock); | |
1569 | goto retry; | |
1570 | } | |
0d9f9a5c | 1571 | qemu_mutex_unlock(&comp_done_lock); |
56e93d26 JQ |
1572 | |
1573 | return pages; | |
1574 | } | |
1575 | ||
31e2ac74 JQ |
1576 | #define PAGE_ALL_CLEAN 0 |
1577 | #define PAGE_TRY_AGAIN 1 | |
1578 | #define PAGE_DIRTY_FOUND 2 | |
3d0684b2 JQ |
1579 | /** |
1580 | * find_dirty_block: find the next dirty page and update any state | |
1581 | * associated with the search process. | |
b9e60928 | 1582 | * |
31e2ac74 JQ |
1583 | * Returns: |
1584 | * PAGE_ALL_CLEAN: no dirty page found, give up | |
1585 | * PAGE_TRY_AGAIN: no dirty page found, retry for next block | |
1586 | * PAGE_DIRTY_FOUND: dirty page found | |
b9e60928 | 1587 | * |
6f37bb8b | 1588 | * @rs: current RAM state |
3d0684b2 JQ |
1589 | * @pss: data about the state of the current dirty page scan |
1590 | * @again: set to false if the search has scanned the whole of RAM | |
b9e60928 | 1591 | */ |
31e2ac74 | 1592 | static int find_dirty_block(RAMState *rs, PageSearchStatus *pss) |
b9e60928 | 1593 | { |
d9e474ea PX |
1594 | /* Update pss->page for the next dirty bit in ramblock */ |
1595 | pss_find_next_dirty(pss); | |
1596 | ||
6f37bb8b | 1597 | if (pss->complete_round && pss->block == rs->last_seen_block && |
a935e30f | 1598 | pss->page >= rs->last_page) { |
b9e60928 DDAG |
1599 | /* |
1600 | * We've been once around the RAM and haven't found anything. | |
1601 | * Give up. | |
1602 | */ | |
31e2ac74 | 1603 | return PAGE_ALL_CLEAN; |
b9e60928 | 1604 | } |
542147f4 DH |
1605 | if (!offset_in_ramblock(pss->block, |
1606 | ((ram_addr_t)pss->page) << TARGET_PAGE_BITS)) { | |
b9e60928 | 1607 | /* Didn't find anything in this RAM Block */ |
a935e30f | 1608 | pss->page = 0; |
b9e60928 DDAG |
1609 | pss->block = QLIST_NEXT_RCU(pss->block, next); |
1610 | if (!pss->block) { | |
48df9d80 XG |
1611 | /* |
1612 | * If memory migration starts over, we will meet a dirtied page | |
1613 | * which may still exists in compression threads's ring, so we | |
1614 | * should flush the compressed data to make sure the new page | |
1615 | * is not overwritten by the old one in the destination. | |
1616 | * | |
1617 | * Also If xbzrle is on, stop using the data compression at this | |
1618 | * point. In theory, xbzrle can do better than compression. | |
1619 | */ | |
1620 | flush_compressed_data(rs); | |
1621 | ||
b9e60928 DDAG |
1622 | /* Hit the end of the list */ |
1623 | pss->block = QLIST_FIRST_RCU(&ram_list.blocks); | |
1624 | /* Flag that we've looped */ | |
1625 | pss->complete_round = true; | |
1a373522 DH |
1626 | /* After the first round, enable XBZRLE. */ |
1627 | if (migrate_use_xbzrle()) { | |
1628 | rs->xbzrle_enabled = true; | |
1629 | } | |
b9e60928 DDAG |
1630 | } |
1631 | /* Didn't find anything this time, but try again on the new block */ | |
31e2ac74 | 1632 | return PAGE_TRY_AGAIN; |
b9e60928 | 1633 | } else { |
31e2ac74 JQ |
1634 | /* We've found something */ |
1635 | return PAGE_DIRTY_FOUND; | |
b9e60928 DDAG |
1636 | } |
1637 | } | |
1638 | ||
3d0684b2 JQ |
1639 | /** |
1640 | * unqueue_page: gets a page of the queue | |
1641 | * | |
a82d593b | 1642 | * Helper for 'get_queued_page' - gets a page off the queue |
a82d593b | 1643 | * |
3d0684b2 JQ |
1644 | * Returns the block of the page (or NULL if none available) |
1645 | * | |
ec481c6c | 1646 | * @rs: current RAM state |
3d0684b2 | 1647 | * @offset: used to return the offset within the RAMBlock |
a82d593b | 1648 | */ |
f20e2865 | 1649 | static RAMBlock *unqueue_page(RAMState *rs, ram_addr_t *offset) |
a82d593b | 1650 | { |
a1fe28df | 1651 | struct RAMSrcPageRequest *entry; |
a82d593b DDAG |
1652 | RAMBlock *block = NULL; |
1653 | ||
a1fe28df | 1654 | if (!postcopy_has_request(rs)) { |
ae526e32 XG |
1655 | return NULL; |
1656 | } | |
1657 | ||
6e8a355d | 1658 | QEMU_LOCK_GUARD(&rs->src_page_req_mutex); |
a1fe28df PX |
1659 | |
1660 | /* | |
1661 | * This should _never_ change even after we take the lock, because no one | |
1662 | * should be taking anything off the request list other than us. | |
1663 | */ | |
1664 | assert(postcopy_has_request(rs)); | |
1665 | ||
1666 | entry = QSIMPLEQ_FIRST(&rs->src_page_requests); | |
1667 | block = entry->rb; | |
1668 | *offset = entry->offset; | |
1669 | ||
777f53c7 TH |
1670 | if (entry->len > TARGET_PAGE_SIZE) { |
1671 | entry->len -= TARGET_PAGE_SIZE; | |
1672 | entry->offset += TARGET_PAGE_SIZE; | |
a1fe28df PX |
1673 | } else { |
1674 | memory_region_unref(block->mr); | |
1675 | QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req); | |
1676 | g_free(entry); | |
1677 | migration_consume_urgent_request(); | |
a82d593b | 1678 | } |
a82d593b DDAG |
1679 | |
1680 | return block; | |
1681 | } | |
1682 | ||
278e2f55 AG |
1683 | #if defined(__linux__) |
1684 | /** | |
1685 | * poll_fault_page: try to get next UFFD write fault page and, if pending fault | |
1686 | * is found, return RAM block pointer and page offset | |
1687 | * | |
1688 | * Returns pointer to the RAMBlock containing faulting page, | |
1689 | * NULL if no write faults are pending | |
1690 | * | |
1691 | * @rs: current RAM state | |
1692 | * @offset: page offset from the beginning of the block | |
1693 | */ | |
1694 | static RAMBlock *poll_fault_page(RAMState *rs, ram_addr_t *offset) | |
1695 | { | |
1696 | struct uffd_msg uffd_msg; | |
1697 | void *page_address; | |
82ea3e3b | 1698 | RAMBlock *block; |
278e2f55 AG |
1699 | int res; |
1700 | ||
1701 | if (!migrate_background_snapshot()) { | |
1702 | return NULL; | |
1703 | } | |
1704 | ||
1705 | res = uffd_read_events(rs->uffdio_fd, &uffd_msg, 1); | |
1706 | if (res <= 0) { | |
1707 | return NULL; | |
1708 | } | |
1709 | ||
1710 | page_address = (void *)(uintptr_t) uffd_msg.arg.pagefault.address; | |
82ea3e3b AG |
1711 | block = qemu_ram_block_from_host(page_address, false, offset); |
1712 | assert(block && (block->flags & RAM_UF_WRITEPROTECT) != 0); | |
1713 | return block; | |
278e2f55 AG |
1714 | } |
1715 | ||
1716 | /** | |
1717 | * ram_save_release_protection: release UFFD write protection after | |
1718 | * a range of pages has been saved | |
1719 | * | |
1720 | * @rs: current RAM state | |
1721 | * @pss: page-search-status structure | |
1722 | * @start_page: index of the first page in the range relative to pss->block | |
1723 | * | |
1724 | * Returns 0 on success, negative value in case of an error | |
1725 | */ | |
1726 | static int ram_save_release_protection(RAMState *rs, PageSearchStatus *pss, | |
1727 | unsigned long start_page) | |
1728 | { | |
1729 | int res = 0; | |
1730 | ||
1731 | /* Check if page is from UFFD-managed region. */ | |
1732 | if (pss->block->flags & RAM_UF_WRITEPROTECT) { | |
1733 | void *page_address = pss->block->host + (start_page << TARGET_PAGE_BITS); | |
258f5c98 | 1734 | uint64_t run_length = (pss->page - start_page) << TARGET_PAGE_BITS; |
278e2f55 AG |
1735 | |
1736 | /* Flush async buffers before un-protect. */ | |
61717ea9 | 1737 | qemu_fflush(pss->pss_channel); |
278e2f55 AG |
1738 | /* Un-protect memory range. */ |
1739 | res = uffd_change_protection(rs->uffdio_fd, page_address, run_length, | |
1740 | false, false); | |
1741 | } | |
1742 | ||
1743 | return res; | |
1744 | } | |
1745 | ||
1746 | /* ram_write_tracking_available: check if kernel supports required UFFD features | |
1747 | * | |
1748 | * Returns true if supports, false otherwise | |
1749 | */ | |
1750 | bool ram_write_tracking_available(void) | |
1751 | { | |
1752 | uint64_t uffd_features; | |
1753 | int res; | |
1754 | ||
1755 | res = uffd_query_features(&uffd_features); | |
1756 | return (res == 0 && | |
1757 | (uffd_features & UFFD_FEATURE_PAGEFAULT_FLAG_WP) != 0); | |
1758 | } | |
1759 | ||
1760 | /* ram_write_tracking_compatible: check if guest configuration is | |
1761 | * compatible with 'write-tracking' | |
1762 | * | |
1763 | * Returns true if compatible, false otherwise | |
1764 | */ | |
1765 | bool ram_write_tracking_compatible(void) | |
1766 | { | |
1767 | const uint64_t uffd_ioctls_mask = BIT(_UFFDIO_WRITEPROTECT); | |
1768 | int uffd_fd; | |
82ea3e3b | 1769 | RAMBlock *block; |
278e2f55 AG |
1770 | bool ret = false; |
1771 | ||
1772 | /* Open UFFD file descriptor */ | |
1773 | uffd_fd = uffd_create_fd(UFFD_FEATURE_PAGEFAULT_FLAG_WP, false); | |
1774 | if (uffd_fd < 0) { | |
1775 | return false; | |
1776 | } | |
1777 | ||
1778 | RCU_READ_LOCK_GUARD(); | |
1779 | ||
82ea3e3b | 1780 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
278e2f55 AG |
1781 | uint64_t uffd_ioctls; |
1782 | ||
1783 | /* Nothing to do with read-only and MMIO-writable regions */ | |
82ea3e3b | 1784 | if (block->mr->readonly || block->mr->rom_device) { |
278e2f55 AG |
1785 | continue; |
1786 | } | |
1787 | /* Try to register block memory via UFFD-IO to track writes */ | |
82ea3e3b | 1788 | if (uffd_register_memory(uffd_fd, block->host, block->max_length, |
278e2f55 AG |
1789 | UFFDIO_REGISTER_MODE_WP, &uffd_ioctls)) { |
1790 | goto out; | |
1791 | } | |
1792 | if ((uffd_ioctls & uffd_ioctls_mask) != uffd_ioctls_mask) { | |
1793 | goto out; | |
1794 | } | |
1795 | } | |
1796 | ret = true; | |
1797 | ||
1798 | out: | |
1799 | uffd_close_fd(uffd_fd); | |
1800 | return ret; | |
1801 | } | |
1802 | ||
f7b9dcfb DH |
1803 | static inline void populate_read_range(RAMBlock *block, ram_addr_t offset, |
1804 | ram_addr_t size) | |
1805 | { | |
5f19a449 DH |
1806 | const ram_addr_t end = offset + size; |
1807 | ||
f7b9dcfb DH |
1808 | /* |
1809 | * We read one byte of each page; this will preallocate page tables if | |
1810 | * required and populate the shared zeropage on MAP_PRIVATE anonymous memory | |
1811 | * where no page was populated yet. This might require adaption when | |
1812 | * supporting other mappings, like shmem. | |
1813 | */ | |
5f19a449 | 1814 | for (; offset < end; offset += block->page_size) { |
f7b9dcfb DH |
1815 | char tmp = *((char *)block->host + offset); |
1816 | ||
1817 | /* Don't optimize the read out */ | |
1818 | asm volatile("" : "+r" (tmp)); | |
1819 | } | |
1820 | } | |
1821 | ||
6fee3a1f DH |
1822 | static inline int populate_read_section(MemoryRegionSection *section, |
1823 | void *opaque) | |
1824 | { | |
1825 | const hwaddr size = int128_get64(section->size); | |
1826 | hwaddr offset = section->offset_within_region; | |
1827 | RAMBlock *block = section->mr->ram_block; | |
1828 | ||
1829 | populate_read_range(block, offset, size); | |
1830 | return 0; | |
1831 | } | |
1832 | ||
eeccb99c | 1833 | /* |
f7b9dcfb DH |
1834 | * ram_block_populate_read: preallocate page tables and populate pages in the |
1835 | * RAM block by reading a byte of each page. | |
eeccb99c AG |
1836 | * |
1837 | * Since it's solely used for userfault_fd WP feature, here we just | |
1838 | * hardcode page size to qemu_real_host_page_size. | |
1839 | * | |
82ea3e3b | 1840 | * @block: RAM block to populate |
eeccb99c | 1841 | */ |
6fee3a1f | 1842 | static void ram_block_populate_read(RAMBlock *rb) |
eeccb99c | 1843 | { |
6fee3a1f DH |
1844 | /* |
1845 | * Skip populating all pages that fall into a discarded range as managed by | |
1846 | * a RamDiscardManager responsible for the mapped memory region of the | |
1847 | * RAMBlock. Such discarded ("logically unplugged") parts of a RAMBlock | |
1848 | * must not get populated automatically. We don't have to track | |
1849 | * modifications via userfaultfd WP reliably, because these pages will | |
1850 | * not be part of the migration stream either way -- see | |
1851 | * ramblock_dirty_bitmap_exclude_discarded_pages(). | |
1852 | * | |
1853 | * Note: The result is only stable while migrating (precopy/postcopy). | |
1854 | */ | |
1855 | if (rb->mr && memory_region_has_ram_discard_manager(rb->mr)) { | |
1856 | RamDiscardManager *rdm = memory_region_get_ram_discard_manager(rb->mr); | |
1857 | MemoryRegionSection section = { | |
1858 | .mr = rb->mr, | |
1859 | .offset_within_region = 0, | |
1860 | .size = rb->mr->size, | |
1861 | }; | |
1862 | ||
1863 | ram_discard_manager_replay_populated(rdm, §ion, | |
1864 | populate_read_section, NULL); | |
1865 | } else { | |
1866 | populate_read_range(rb, 0, rb->used_length); | |
1867 | } | |
eeccb99c AG |
1868 | } |
1869 | ||
1870 | /* | |
1871 | * ram_write_tracking_prepare: prepare for UFFD-WP memory tracking | |
1872 | */ | |
1873 | void ram_write_tracking_prepare(void) | |
1874 | { | |
82ea3e3b | 1875 | RAMBlock *block; |
eeccb99c AG |
1876 | |
1877 | RCU_READ_LOCK_GUARD(); | |
1878 | ||
82ea3e3b | 1879 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
eeccb99c | 1880 | /* Nothing to do with read-only and MMIO-writable regions */ |
82ea3e3b | 1881 | if (block->mr->readonly || block->mr->rom_device) { |
eeccb99c AG |
1882 | continue; |
1883 | } | |
1884 | ||
1885 | /* | |
1886 | * Populate pages of the RAM block before enabling userfault_fd | |
1887 | * write protection. | |
1888 | * | |
1889 | * This stage is required since ioctl(UFFDIO_WRITEPROTECT) with | |
1890 | * UFFDIO_WRITEPROTECT_MODE_WP mode setting would silently skip | |
1891 | * pages with pte_none() entries in page table. | |
1892 | */ | |
f7b9dcfb | 1893 | ram_block_populate_read(block); |
eeccb99c AG |
1894 | } |
1895 | } | |
1896 | ||
e41c5770 DH |
1897 | static inline int uffd_protect_section(MemoryRegionSection *section, |
1898 | void *opaque) | |
1899 | { | |
1900 | const hwaddr size = int128_get64(section->size); | |
1901 | const hwaddr offset = section->offset_within_region; | |
1902 | RAMBlock *rb = section->mr->ram_block; | |
1903 | int uffd_fd = (uintptr_t)opaque; | |
1904 | ||
1905 | return uffd_change_protection(uffd_fd, rb->host + offset, size, true, | |
1906 | false); | |
1907 | } | |
1908 | ||
1909 | static int ram_block_uffd_protect(RAMBlock *rb, int uffd_fd) | |
1910 | { | |
1911 | assert(rb->flags & RAM_UF_WRITEPROTECT); | |
1912 | ||
1913 | /* See ram_block_populate_read() */ | |
1914 | if (rb->mr && memory_region_has_ram_discard_manager(rb->mr)) { | |
1915 | RamDiscardManager *rdm = memory_region_get_ram_discard_manager(rb->mr); | |
1916 | MemoryRegionSection section = { | |
1917 | .mr = rb->mr, | |
1918 | .offset_within_region = 0, | |
1919 | .size = rb->mr->size, | |
1920 | }; | |
1921 | ||
1922 | return ram_discard_manager_replay_populated(rdm, §ion, | |
1923 | uffd_protect_section, | |
1924 | (void *)(uintptr_t)uffd_fd); | |
1925 | } | |
1926 | return uffd_change_protection(uffd_fd, rb->host, | |
1927 | rb->used_length, true, false); | |
1928 | } | |
1929 | ||
278e2f55 AG |
1930 | /* |
1931 | * ram_write_tracking_start: start UFFD-WP memory tracking | |
1932 | * | |
1933 | * Returns 0 for success or negative value in case of error | |
1934 | */ | |
1935 | int ram_write_tracking_start(void) | |
1936 | { | |
1937 | int uffd_fd; | |
1938 | RAMState *rs = ram_state; | |
82ea3e3b | 1939 | RAMBlock *block; |
278e2f55 AG |
1940 | |
1941 | /* Open UFFD file descriptor */ | |
1942 | uffd_fd = uffd_create_fd(UFFD_FEATURE_PAGEFAULT_FLAG_WP, true); | |
1943 | if (uffd_fd < 0) { | |
1944 | return uffd_fd; | |
1945 | } | |
1946 | rs->uffdio_fd = uffd_fd; | |
1947 | ||
1948 | RCU_READ_LOCK_GUARD(); | |
1949 | ||
82ea3e3b | 1950 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
278e2f55 | 1951 | /* Nothing to do with read-only and MMIO-writable regions */ |
82ea3e3b | 1952 | if (block->mr->readonly || block->mr->rom_device) { |
278e2f55 AG |
1953 | continue; |
1954 | } | |
1955 | ||
1956 | /* Register block memory with UFFD to track writes */ | |
82ea3e3b AG |
1957 | if (uffd_register_memory(rs->uffdio_fd, block->host, |
1958 | block->max_length, UFFDIO_REGISTER_MODE_WP, NULL)) { | |
278e2f55 AG |
1959 | goto fail; |
1960 | } | |
72ef3a37 DH |
1961 | block->flags |= RAM_UF_WRITEPROTECT; |
1962 | memory_region_ref(block->mr); | |
1963 | ||
278e2f55 | 1964 | /* Apply UFFD write protection to the block memory range */ |
e41c5770 | 1965 | if (ram_block_uffd_protect(block, uffd_fd)) { |
278e2f55 AG |
1966 | goto fail; |
1967 | } | |
278e2f55 | 1968 | |
82ea3e3b AG |
1969 | trace_ram_write_tracking_ramblock_start(block->idstr, block->page_size, |
1970 | block->host, block->max_length); | |
278e2f55 AG |
1971 | } |
1972 | ||
1973 | return 0; | |
1974 | ||
1975 | fail: | |
1976 | error_report("ram_write_tracking_start() failed: restoring initial memory state"); | |
1977 | ||
82ea3e3b AG |
1978 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
1979 | if ((block->flags & RAM_UF_WRITEPROTECT) == 0) { | |
278e2f55 AG |
1980 | continue; |
1981 | } | |
82ea3e3b | 1982 | uffd_unregister_memory(rs->uffdio_fd, block->host, block->max_length); |
278e2f55 | 1983 | /* Cleanup flags and remove reference */ |
82ea3e3b AG |
1984 | block->flags &= ~RAM_UF_WRITEPROTECT; |
1985 | memory_region_unref(block->mr); | |
278e2f55 AG |
1986 | } |
1987 | ||
1988 | uffd_close_fd(uffd_fd); | |
1989 | rs->uffdio_fd = -1; | |
1990 | return -1; | |
1991 | } | |
1992 | ||
1993 | /** | |
1994 | * ram_write_tracking_stop: stop UFFD-WP memory tracking and remove protection | |
1995 | */ | |
1996 | void ram_write_tracking_stop(void) | |
1997 | { | |
1998 | RAMState *rs = ram_state; | |
82ea3e3b | 1999 | RAMBlock *block; |
278e2f55 AG |
2000 | |
2001 | RCU_READ_LOCK_GUARD(); | |
2002 | ||
82ea3e3b AG |
2003 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
2004 | if ((block->flags & RAM_UF_WRITEPROTECT) == 0) { | |
278e2f55 AG |
2005 | continue; |
2006 | } | |
82ea3e3b | 2007 | uffd_unregister_memory(rs->uffdio_fd, block->host, block->max_length); |
278e2f55 | 2008 | |
82ea3e3b AG |
2009 | trace_ram_write_tracking_ramblock_stop(block->idstr, block->page_size, |
2010 | block->host, block->max_length); | |
278e2f55 AG |
2011 | |
2012 | /* Cleanup flags and remove reference */ | |
82ea3e3b AG |
2013 | block->flags &= ~RAM_UF_WRITEPROTECT; |
2014 | memory_region_unref(block->mr); | |
278e2f55 AG |
2015 | } |
2016 | ||
2017 | /* Finally close UFFD file descriptor */ | |
2018 | uffd_close_fd(rs->uffdio_fd); | |
2019 | rs->uffdio_fd = -1; | |
2020 | } | |
2021 | ||
2022 | #else | |
2023 | /* No target OS support, stubs just fail or ignore */ | |
2024 | ||
2025 | static RAMBlock *poll_fault_page(RAMState *rs, ram_addr_t *offset) | |
2026 | { | |
2027 | (void) rs; | |
2028 | (void) offset; | |
2029 | ||
2030 | return NULL; | |
2031 | } | |
2032 | ||
2033 | static int ram_save_release_protection(RAMState *rs, PageSearchStatus *pss, | |
2034 | unsigned long start_page) | |
2035 | { | |
2036 | (void) rs; | |
2037 | (void) pss; | |
2038 | (void) start_page; | |
2039 | ||
2040 | return 0; | |
2041 | } | |
2042 | ||
2043 | bool ram_write_tracking_available(void) | |
2044 | { | |
2045 | return false; | |
2046 | } | |
2047 | ||
2048 | bool ram_write_tracking_compatible(void) | |
2049 | { | |
2050 | assert(0); | |
2051 | return false; | |
2052 | } | |
2053 | ||
2054 | int ram_write_tracking_start(void) | |
2055 | { | |
2056 | assert(0); | |
2057 | return -1; | |
2058 | } | |
2059 | ||
2060 | void ram_write_tracking_stop(void) | |
2061 | { | |
2062 | assert(0); | |
2063 | } | |
2064 | #endif /* defined(__linux__) */ | |
2065 | ||
3d0684b2 | 2066 | /** |
ff1543af | 2067 | * get_queued_page: unqueue a page from the postcopy requests |
3d0684b2 JQ |
2068 | * |
2069 | * Skips pages that are already sent (!dirty) | |
a82d593b | 2070 | * |
a5f7b1a6 | 2071 | * Returns true if a queued page is found |
a82d593b | 2072 | * |
6f37bb8b | 2073 | * @rs: current RAM state |
3d0684b2 | 2074 | * @pss: data about the state of the current dirty page scan |
a82d593b | 2075 | */ |
f20e2865 | 2076 | static bool get_queued_page(RAMState *rs, PageSearchStatus *pss) |
a82d593b DDAG |
2077 | { |
2078 | RAMBlock *block; | |
2079 | ram_addr_t offset; | |
777f53c7 TH |
2080 | bool dirty; |
2081 | ||
2082 | do { | |
2083 | block = unqueue_page(rs, &offset); | |
2084 | /* | |
2085 | * We're sending this page, and since it's postcopy nothing else | |
2086 | * will dirty it, and we must make sure it doesn't get sent again | |
2087 | * even if this queue request was received after the background | |
2088 | * search already sent it. | |
2089 | */ | |
2090 | if (block) { | |
2091 | unsigned long page; | |
2092 | ||
2093 | page = offset >> TARGET_PAGE_BITS; | |
2094 | dirty = test_bit(page, block->bmap); | |
2095 | if (!dirty) { | |
2096 | trace_get_queued_page_not_dirty(block->idstr, (uint64_t)offset, | |
2097 | page); | |
2098 | } else { | |
2099 | trace_get_queued_page(block->idstr, (uint64_t)offset, page); | |
2100 | } | |
2101 | } | |
a82d593b | 2102 | |
777f53c7 | 2103 | } while (block && !dirty); |
a82d593b | 2104 | |
b062106d | 2105 | if (!block) { |
278e2f55 AG |
2106 | /* |
2107 | * Poll write faults too if background snapshot is enabled; that's | |
2108 | * when we have vcpus got blocked by the write protected pages. | |
2109 | */ | |
2110 | block = poll_fault_page(rs, &offset); | |
2111 | } | |
2112 | ||
a82d593b | 2113 | if (block) { |
a82d593b DDAG |
2114 | /* |
2115 | * We want the background search to continue from the queued page | |
2116 | * since the guest is likely to want other pages near to the page | |
2117 | * it just requested. | |
2118 | */ | |
2119 | pss->block = block; | |
a935e30f | 2120 | pss->page = offset >> TARGET_PAGE_BITS; |
422314e7 WY |
2121 | |
2122 | /* | |
2123 | * This unqueued page would break the "one round" check, even is | |
2124 | * really rare. | |
2125 | */ | |
2126 | pss->complete_round = false; | |
a82d593b DDAG |
2127 | } |
2128 | ||
2129 | return !!block; | |
2130 | } | |
2131 | ||
6c595cde | 2132 | /** |
5e58f968 JQ |
2133 | * migration_page_queue_free: drop any remaining pages in the ram |
2134 | * request queue | |
6c595cde | 2135 | * |
3d0684b2 JQ |
2136 | * It should be empty at the end anyway, but in error cases there may |
2137 | * be some left. in case that there is any page left, we drop it. | |
2138 | * | |
6c595cde | 2139 | */ |
83c13382 | 2140 | static void migration_page_queue_free(RAMState *rs) |
6c595cde | 2141 | { |
ec481c6c | 2142 | struct RAMSrcPageRequest *mspr, *next_mspr; |
6c595cde DDAG |
2143 | /* This queue generally should be empty - but in the case of a failed |
2144 | * migration might have some droppings in. | |
2145 | */ | |
89ac5a1d | 2146 | RCU_READ_LOCK_GUARD(); |
ec481c6c | 2147 | QSIMPLEQ_FOREACH_SAFE(mspr, &rs->src_page_requests, next_req, next_mspr) { |
6c595cde | 2148 | memory_region_unref(mspr->rb->mr); |
ec481c6c | 2149 | QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req); |
6c595cde DDAG |
2150 | g_free(mspr); |
2151 | } | |
6c595cde DDAG |
2152 | } |
2153 | ||
2154 | /** | |
3d0684b2 JQ |
2155 | * ram_save_queue_pages: queue the page for transmission |
2156 | * | |
2157 | * A request from postcopy destination for example. | |
2158 | * | |
2159 | * Returns zero on success or negative on error | |
2160 | * | |
3d0684b2 JQ |
2161 | * @rbname: Name of the RAMBLock of the request. NULL means the |
2162 | * same that last one. | |
2163 | * @start: starting address from the start of the RAMBlock | |
2164 | * @len: length (in bytes) to send | |
6c595cde | 2165 | */ |
96506894 | 2166 | int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len) |
6c595cde DDAG |
2167 | { |
2168 | RAMBlock *ramblock; | |
53518d94 | 2169 | RAMState *rs = ram_state; |
6c595cde | 2170 | |
9360447d | 2171 | ram_counters.postcopy_requests++; |
89ac5a1d DDAG |
2172 | RCU_READ_LOCK_GUARD(); |
2173 | ||
6c595cde DDAG |
2174 | if (!rbname) { |
2175 | /* Reuse last RAMBlock */ | |
68a098f3 | 2176 | ramblock = rs->last_req_rb; |
6c595cde DDAG |
2177 | |
2178 | if (!ramblock) { | |
2179 | /* | |
2180 | * Shouldn't happen, we can't reuse the last RAMBlock if | |
2181 | * it's the 1st request. | |
2182 | */ | |
2183 | error_report("ram_save_queue_pages no previous block"); | |
03acb4e9 | 2184 | return -1; |
6c595cde DDAG |
2185 | } |
2186 | } else { | |
2187 | ramblock = qemu_ram_block_by_name(rbname); | |
2188 | ||
2189 | if (!ramblock) { | |
2190 | /* We shouldn't be asked for a non-existent RAMBlock */ | |
2191 | error_report("ram_save_queue_pages no block '%s'", rbname); | |
03acb4e9 | 2192 | return -1; |
6c595cde | 2193 | } |
68a098f3 | 2194 | rs->last_req_rb = ramblock; |
6c595cde DDAG |
2195 | } |
2196 | trace_ram_save_queue_pages(ramblock->idstr, start, len); | |
542147f4 | 2197 | if (!offset_in_ramblock(ramblock, start + len - 1)) { |
9458ad6b JQ |
2198 | error_report("%s request overrun start=" RAM_ADDR_FMT " len=" |
2199 | RAM_ADDR_FMT " blocklen=" RAM_ADDR_FMT, | |
6c595cde | 2200 | __func__, start, len, ramblock->used_length); |
03acb4e9 | 2201 | return -1; |
6c595cde DDAG |
2202 | } |
2203 | ||
93589827 PX |
2204 | /* |
2205 | * When with postcopy preempt, we send back the page directly in the | |
2206 | * rp-return thread. | |
2207 | */ | |
2208 | if (postcopy_preempt_active()) { | |
2209 | ram_addr_t page_start = start >> TARGET_PAGE_BITS; | |
2210 | size_t page_size = qemu_ram_pagesize(ramblock); | |
2211 | PageSearchStatus *pss = &ram_state->pss[RAM_CHANNEL_POSTCOPY]; | |
2212 | int ret = 0; | |
2213 | ||
2214 | qemu_mutex_lock(&rs->bitmap_mutex); | |
2215 | ||
2216 | pss_init(pss, ramblock, page_start); | |
2217 | /* | |
2218 | * Always use the preempt channel, and make sure it's there. It's | |
2219 | * safe to access without lock, because when rp-thread is running | |
2220 | * we should be the only one who operates on the qemufile | |
2221 | */ | |
2222 | pss->pss_channel = migrate_get_current()->postcopy_qemufile_src; | |
93589827 PX |
2223 | assert(pss->pss_channel); |
2224 | ||
2225 | /* | |
2226 | * It must be either one or multiple of host page size. Just | |
2227 | * assert; if something wrong we're mostly split brain anyway. | |
2228 | */ | |
2229 | assert(len % page_size == 0); | |
2230 | while (len) { | |
2231 | if (ram_save_host_page_urgent(pss)) { | |
2232 | error_report("%s: ram_save_host_page_urgent() failed: " | |
2233 | "ramblock=%s, start_addr=0x"RAM_ADDR_FMT, | |
2234 | __func__, ramblock->idstr, start); | |
2235 | ret = -1; | |
2236 | break; | |
2237 | } | |
2238 | /* | |
2239 | * NOTE: after ram_save_host_page_urgent() succeeded, pss->page | |
2240 | * will automatically be moved and point to the next host page | |
2241 | * we're going to send, so no need to update here. | |
2242 | * | |
2243 | * Normally QEMU never sends >1 host page in requests, so | |
2244 | * logically we don't even need that as the loop should only | |
2245 | * run once, but just to be consistent. | |
2246 | */ | |
2247 | len -= page_size; | |
2248 | }; | |
2249 | qemu_mutex_unlock(&rs->bitmap_mutex); | |
2250 | ||
2251 | return ret; | |
2252 | } | |
2253 | ||
ec481c6c | 2254 | struct RAMSrcPageRequest *new_entry = |
b21e2380 | 2255 | g_new0(struct RAMSrcPageRequest, 1); |
6c595cde DDAG |
2256 | new_entry->rb = ramblock; |
2257 | new_entry->offset = start; | |
2258 | new_entry->len = len; | |
2259 | ||
2260 | memory_region_ref(ramblock->mr); | |
ec481c6c JQ |
2261 | qemu_mutex_lock(&rs->src_page_req_mutex); |
2262 | QSIMPLEQ_INSERT_TAIL(&rs->src_page_requests, new_entry, next_req); | |
e03a34f8 | 2263 | migration_make_urgent_request(); |
ec481c6c | 2264 | qemu_mutex_unlock(&rs->src_page_req_mutex); |
6c595cde DDAG |
2265 | |
2266 | return 0; | |
6c595cde DDAG |
2267 | } |
2268 | ||
d7400a34 XG |
2269 | static bool save_page_use_compression(RAMState *rs) |
2270 | { | |
2271 | if (!migrate_use_compression()) { | |
2272 | return false; | |
2273 | } | |
2274 | ||
2275 | /* | |
1a373522 DH |
2276 | * If xbzrle is enabled (e.g., after first round of migration), stop |
2277 | * using the data compression. In theory, xbzrle can do better than | |
2278 | * compression. | |
d7400a34 | 2279 | */ |
1a373522 DH |
2280 | if (rs->xbzrle_enabled) { |
2281 | return false; | |
d7400a34 XG |
2282 | } |
2283 | ||
1a373522 | 2284 | return true; |
d7400a34 XG |
2285 | } |
2286 | ||
5e5fdcff XG |
2287 | /* |
2288 | * try to compress the page before posting it out, return true if the page | |
2289 | * has been properly handled by compression, otherwise needs other | |
2290 | * paths to handle it | |
2291 | */ | |
ec6f3ab9 PX |
2292 | static bool save_compress_page(RAMState *rs, PageSearchStatus *pss, |
2293 | RAMBlock *block, ram_addr_t offset) | |
5e5fdcff XG |
2294 | { |
2295 | if (!save_page_use_compression(rs)) { | |
2296 | return false; | |
2297 | } | |
2298 | ||
2299 | /* | |
2300 | * When starting the process of a new block, the first page of | |
2301 | * the block should be sent out before other pages in the same | |
2302 | * block, and all the pages in last block should have been sent | |
2303 | * out, keeping this order is important, because the 'cont' flag | |
2304 | * is used to avoid resending the block name. | |
2305 | * | |
2306 | * We post the fist page as normal page as compression will take | |
2307 | * much CPU resource. | |
2308 | */ | |
ec6f3ab9 | 2309 | if (block != pss->last_sent_block) { |
5e5fdcff XG |
2310 | flush_compressed_data(rs); |
2311 | return false; | |
2312 | } | |
2313 | ||
eaa238ab | 2314 | if (compress_page_with_multi_thread(block, offset) > 0) { |
5e5fdcff XG |
2315 | return true; |
2316 | } | |
2317 | ||
76e03000 | 2318 | compression_counters.busy++; |
5e5fdcff XG |
2319 | return false; |
2320 | } | |
2321 | ||
a82d593b | 2322 | /** |
4010ba38 | 2323 | * ram_save_target_page_legacy: save one target page |
a82d593b | 2324 | * |
3d0684b2 | 2325 | * Returns the number of pages written |
a82d593b | 2326 | * |
6f37bb8b | 2327 | * @rs: current RAM state |
3d0684b2 | 2328 | * @pss: data about the page we want to send |
a82d593b | 2329 | */ |
4010ba38 | 2330 | static int ram_save_target_page_legacy(RAMState *rs, PageSearchStatus *pss) |
a82d593b | 2331 | { |
a8ec91f9 | 2332 | RAMBlock *block = pss->block; |
8bba004c | 2333 | ram_addr_t offset = ((ram_addr_t)pss->page) << TARGET_PAGE_BITS; |
a8ec91f9 XG |
2334 | int res; |
2335 | ||
61717ea9 | 2336 | if (control_save_page(pss, block, offset, &res)) { |
a8ec91f9 XG |
2337 | return res; |
2338 | } | |
2339 | ||
ec6f3ab9 | 2340 | if (save_compress_page(rs, pss, block, offset)) { |
5e5fdcff | 2341 | return 1; |
d7400a34 XG |
2342 | } |
2343 | ||
37502df3 | 2344 | res = save_zero_page(pss, pss->pss_channel, block, offset); |
d7400a34 XG |
2345 | if (res > 0) { |
2346 | /* Must let xbzrle know, otherwise a previous (now 0'd) cached | |
2347 | * page would be stale | |
2348 | */ | |
ef5c3d13 | 2349 | if (rs->xbzrle_enabled) { |
d7400a34 XG |
2350 | XBZRLE_cache_lock(); |
2351 | xbzrle_cache_zero_page(rs, block->offset + offset); | |
2352 | XBZRLE_cache_unlock(); | |
2353 | } | |
d7400a34 XG |
2354 | return res; |
2355 | } | |
2356 | ||
da3f56cb | 2357 | /* |
6f39c90b PX |
2358 | * Do not use multifd in postcopy as one whole host page should be |
2359 | * placed. Meanwhile postcopy requires atomic update of pages, so even | |
2360 | * if host page size == guest page size the dest guest during run may | |
2361 | * still see partially copied pages which is data corruption. | |
da3f56cb | 2362 | */ |
6f39c90b | 2363 | if (migrate_use_multifd() && !migration_in_postcopy()) { |
61717ea9 | 2364 | return ram_save_multifd_page(pss->pss_channel, block, offset); |
a82d593b DDAG |
2365 | } |
2366 | ||
05931ec5 | 2367 | return ram_save_page(rs, pss); |
a82d593b DDAG |
2368 | } |
2369 | ||
d9e474ea PX |
2370 | /* Should be called before sending a host page */ |
2371 | static void pss_host_page_prepare(PageSearchStatus *pss) | |
2372 | { | |
2373 | /* How many guest pages are there in one host page? */ | |
2374 | size_t guest_pfns = qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS; | |
2375 | ||
2376 | pss->host_page_sending = true; | |
301d7ffe PX |
2377 | if (guest_pfns <= 1) { |
2378 | /* | |
2379 | * This covers both when guest psize == host psize, or when guest | |
2380 | * has larger psize than the host (guest_pfns==0). | |
2381 | * | |
2382 | * For the latter, we always send one whole guest page per | |
2383 | * iteration of the host page (example: an Alpha VM on x86 host | |
2384 | * will have guest psize 8K while host psize 4K). | |
2385 | */ | |
2386 | pss->host_page_start = pss->page; | |
2387 | pss->host_page_end = pss->page + 1; | |
2388 | } else { | |
2389 | /* | |
2390 | * The host page spans over multiple guest pages, we send them | |
2391 | * within the same host page iteration. | |
2392 | */ | |
2393 | pss->host_page_start = ROUND_DOWN(pss->page, guest_pfns); | |
2394 | pss->host_page_end = ROUND_UP(pss->page + 1, guest_pfns); | |
2395 | } | |
d9e474ea PX |
2396 | } |
2397 | ||
2398 | /* | |
2399 | * Whether the page pointed by PSS is within the host page being sent. | |
2400 | * Must be called after a previous pss_host_page_prepare(). | |
2401 | */ | |
2402 | static bool pss_within_range(PageSearchStatus *pss) | |
2403 | { | |
2404 | ram_addr_t ram_addr; | |
2405 | ||
2406 | assert(pss->host_page_sending); | |
2407 | ||
2408 | /* Over host-page boundary? */ | |
2409 | if (pss->page >= pss->host_page_end) { | |
2410 | return false; | |
2411 | } | |
2412 | ||
2413 | ram_addr = ((ram_addr_t)pss->page) << TARGET_PAGE_BITS; | |
2414 | ||
2415 | return offset_in_ramblock(pss->block, ram_addr); | |
2416 | } | |
2417 | ||
2418 | static void pss_host_page_finish(PageSearchStatus *pss) | |
2419 | { | |
2420 | pss->host_page_sending = false; | |
2421 | /* This is not needed, but just to reset it */ | |
2422 | pss->host_page_start = pss->host_page_end = 0; | |
2423 | } | |
2424 | ||
93589827 PX |
2425 | /* |
2426 | * Send an urgent host page specified by `pss'. Need to be called with | |
2427 | * bitmap_mutex held. | |
2428 | * | |
2429 | * Returns 0 if save host page succeeded, false otherwise. | |
2430 | */ | |
2431 | static int ram_save_host_page_urgent(PageSearchStatus *pss) | |
2432 | { | |
2433 | bool page_dirty, sent = false; | |
2434 | RAMState *rs = ram_state; | |
2435 | int ret = 0; | |
2436 | ||
2437 | trace_postcopy_preempt_send_host_page(pss->block->idstr, pss->page); | |
2438 | pss_host_page_prepare(pss); | |
2439 | ||
2440 | /* | |
2441 | * If precopy is sending the same page, let it be done in precopy, or | |
2442 | * we could send the same page in two channels and none of them will | |
2443 | * receive the whole page. | |
2444 | */ | |
2445 | if (pss_overlap(pss, &ram_state->pss[RAM_CHANNEL_PRECOPY])) { | |
2446 | trace_postcopy_preempt_hit(pss->block->idstr, | |
2447 | pss->page << TARGET_PAGE_BITS); | |
2448 | return 0; | |
2449 | } | |
2450 | ||
2451 | do { | |
2452 | page_dirty = migration_bitmap_clear_dirty(rs, pss->block, pss->page); | |
2453 | ||
2454 | if (page_dirty) { | |
2455 | /* Be strict to return code; it must be 1, or what else? */ | |
4010ba38 | 2456 | if (migration_ops->ram_save_target_page(rs, pss) != 1) { |
93589827 PX |
2457 | error_report_once("%s: ram_save_target_page failed", __func__); |
2458 | ret = -1; | |
2459 | goto out; | |
2460 | } | |
2461 | sent = true; | |
2462 | } | |
2463 | pss_find_next_dirty(pss); | |
2464 | } while (pss_within_range(pss)); | |
2465 | out: | |
2466 | pss_host_page_finish(pss); | |
2467 | /* For urgent requests, flush immediately if sent */ | |
2468 | if (sent) { | |
2469 | qemu_fflush(pss->pss_channel); | |
2470 | } | |
2471 | return ret; | |
2472 | } | |
2473 | ||
a82d593b | 2474 | /** |
3d0684b2 | 2475 | * ram_save_host_page: save a whole host page |
a82d593b | 2476 | * |
3d0684b2 JQ |
2477 | * Starting at *offset send pages up to the end of the current host |
2478 | * page. It's valid for the initial offset to point into the middle of | |
2479 | * a host page in which case the remainder of the hostpage is sent. | |
2480 | * Only dirty target pages are sent. Note that the host page size may | |
2481 | * be a huge page for this block. | |
f3321554 | 2482 | * |
1eb3fc0a DDAG |
2483 | * The saving stops at the boundary of the used_length of the block |
2484 | * if the RAMBlock isn't a multiple of the host page size. | |
a82d593b | 2485 | * |
f3321554 PX |
2486 | * The caller must be with ram_state.bitmap_mutex held to call this |
2487 | * function. Note that this function can temporarily release the lock, but | |
2488 | * when the function is returned it'll make sure the lock is still held. | |
2489 | * | |
3d0684b2 JQ |
2490 | * Returns the number of pages written or negative on error |
2491 | * | |
6f37bb8b | 2492 | * @rs: current RAM state |
3d0684b2 | 2493 | * @pss: data about the page we want to send |
a82d593b | 2494 | */ |
05931ec5 | 2495 | static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss) |
a82d593b | 2496 | { |
f3321554 | 2497 | bool page_dirty, preempt_active = postcopy_preempt_active(); |
a82d593b | 2498 | int tmppages, pages = 0; |
a935e30f JQ |
2499 | size_t pagesize_bits = |
2500 | qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS; | |
278e2f55 AG |
2501 | unsigned long start_page = pss->page; |
2502 | int res; | |
4c011c37 | 2503 | |
fbd162e6 | 2504 | if (ramblock_is_ignored(pss->block)) { |
b895de50 CLG |
2505 | error_report("block %s should not be migrated !", pss->block->idstr); |
2506 | return 0; | |
2507 | } | |
2508 | ||
d9e474ea PX |
2509 | /* Update host page boundary information */ |
2510 | pss_host_page_prepare(pss); | |
2511 | ||
a82d593b | 2512 | do { |
f3321554 | 2513 | page_dirty = migration_bitmap_clear_dirty(rs, pss->block, pss->page); |
a82d593b | 2514 | |
f3321554 PX |
2515 | /* Check the pages is dirty and if it is send it */ |
2516 | if (page_dirty) { | |
ba1b7c81 | 2517 | /* |
f3321554 PX |
2518 | * Properly yield the lock only in postcopy preempt mode |
2519 | * because both migration thread and rp-return thread can | |
2520 | * operate on the bitmaps. | |
ba1b7c81 | 2521 | */ |
f3321554 PX |
2522 | if (preempt_active) { |
2523 | qemu_mutex_unlock(&rs->bitmap_mutex); | |
ba1b7c81 | 2524 | } |
4010ba38 | 2525 | tmppages = migration_ops->ram_save_target_page(rs, pss); |
f3321554 PX |
2526 | if (tmppages >= 0) { |
2527 | pages += tmppages; | |
2528 | /* | |
2529 | * Allow rate limiting to happen in the middle of huge pages if | |
2530 | * something is sent in the current iteration. | |
2531 | */ | |
2532 | if (pagesize_bits > 1 && tmppages > 0) { | |
2533 | migration_rate_limit(); | |
2534 | } | |
2535 | } | |
2536 | if (preempt_active) { | |
2537 | qemu_mutex_lock(&rs->bitmap_mutex); | |
2538 | } | |
2539 | } else { | |
2540 | tmppages = 0; | |
23feba90 | 2541 | } |
f3321554 PX |
2542 | |
2543 | if (tmppages < 0) { | |
d9e474ea | 2544 | pss_host_page_finish(pss); |
f3321554 PX |
2545 | return tmppages; |
2546 | } | |
2547 | ||
d9e474ea PX |
2548 | pss_find_next_dirty(pss); |
2549 | } while (pss_within_range(pss)); | |
2550 | ||
2551 | pss_host_page_finish(pss); | |
278e2f55 AG |
2552 | |
2553 | res = ram_save_release_protection(rs, pss, start_page); | |
2554 | return (res < 0 ? res : pages); | |
a82d593b | 2555 | } |
6c595cde | 2556 | |
56e93d26 | 2557 | /** |
3d0684b2 | 2558 | * ram_find_and_save_block: finds a dirty page and sends it to f |
56e93d26 JQ |
2559 | * |
2560 | * Called within an RCU critical section. | |
2561 | * | |
e8f3735f XG |
2562 | * Returns the number of pages written where zero means no dirty pages, |
2563 | * or negative on error | |
56e93d26 | 2564 | * |
6f37bb8b | 2565 | * @rs: current RAM state |
a82d593b DDAG |
2566 | * |
2567 | * On systems where host-page-size > target-page-size it will send all the | |
2568 | * pages in a host page that are dirty. | |
56e93d26 | 2569 | */ |
05931ec5 | 2570 | static int ram_find_and_save_block(RAMState *rs) |
56e93d26 | 2571 | { |
f1668764 | 2572 | PageSearchStatus *pss = &rs->pss[RAM_CHANNEL_PRECOPY]; |
56e93d26 | 2573 | int pages = 0; |
56e93d26 | 2574 | |
0827b9e9 | 2575 | /* No dirty page as there is zero RAM */ |
8d80e195 | 2576 | if (!rs->ram_bytes_total) { |
0827b9e9 AA |
2577 | return pages; |
2578 | } | |
2579 | ||
4934a5dd PX |
2580 | /* |
2581 | * Always keep last_seen_block/last_page valid during this procedure, | |
2582 | * because find_dirty_block() relies on these values (e.g., we compare | |
2583 | * last_seen_block with pss.block to see whether we searched all the | |
2584 | * ramblocks) to detect the completion of migration. Having NULL value | |
2585 | * of last_seen_block can conditionally cause below loop to run forever. | |
2586 | */ | |
2587 | if (!rs->last_seen_block) { | |
2588 | rs->last_seen_block = QLIST_FIRST_RCU(&ram_list.blocks); | |
2589 | rs->last_page = 0; | |
2590 | } | |
2591 | ||
f1668764 | 2592 | pss_init(pss, rs->last_seen_block, rs->last_page); |
b8fb8cb7 | 2593 | |
31e2ac74 | 2594 | while (true){ |
51efd36f | 2595 | if (!get_queued_page(rs, pss)) { |
b062106d | 2596 | /* priority queue empty, so just search for something dirty */ |
31e2ac74 JQ |
2597 | int res = find_dirty_block(rs, pss); |
2598 | if (res != PAGE_DIRTY_FOUND) { | |
2599 | if (res == PAGE_ALL_CLEAN) { | |
51efd36f | 2600 | break; |
31e2ac74 JQ |
2601 | } else if (res == PAGE_TRY_AGAIN) { |
2602 | continue; | |
51efd36f JQ |
2603 | } |
2604 | } | |
56e93d26 | 2605 | } |
51efd36f | 2606 | pages = ram_save_host_page(rs, pss); |
31e2ac74 JQ |
2607 | if (pages) { |
2608 | break; | |
2609 | } | |
2610 | } | |
56e93d26 | 2611 | |
f1668764 PX |
2612 | rs->last_seen_block = pss->block; |
2613 | rs->last_page = pss->page; | |
56e93d26 JQ |
2614 | |
2615 | return pages; | |
2616 | } | |
2617 | ||
2618 | void acct_update_position(QEMUFile *f, size_t size, bool zero) | |
2619 | { | |
2620 | uint64_t pages = size / TARGET_PAGE_SIZE; | |
f7ccd61b | 2621 | |
56e93d26 | 2622 | if (zero) { |
abce5fa1 | 2623 | stat64_add(&ram_counters.duplicate, pages); |
56e93d26 | 2624 | } else { |
abce5fa1 | 2625 | stat64_add(&ram_counters.normal, pages); |
4c2d0f6d | 2626 | ram_transferred_add(size); |
1a93bd2f | 2627 | qemu_file_credit_transfer(f, size); |
56e93d26 JQ |
2628 | } |
2629 | } | |
2630 | ||
8008a272 | 2631 | static uint64_t ram_bytes_total_with_ignored(void) |
56e93d26 JQ |
2632 | { |
2633 | RAMBlock *block; | |
2634 | uint64_t total = 0; | |
2635 | ||
89ac5a1d DDAG |
2636 | RCU_READ_LOCK_GUARD(); |
2637 | ||
8008a272 JQ |
2638 | RAMBLOCK_FOREACH_MIGRATABLE(block) { |
2639 | total += block->used_length; | |
99e15582 | 2640 | } |
56e93d26 JQ |
2641 | return total; |
2642 | } | |
2643 | ||
fbd162e6 YK |
2644 | uint64_t ram_bytes_total(void) |
2645 | { | |
8008a272 JQ |
2646 | RAMBlock *block; |
2647 | uint64_t total = 0; | |
2648 | ||
2649 | RCU_READ_LOCK_GUARD(); | |
2650 | ||
2651 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
2652 | total += block->used_length; | |
2653 | } | |
2654 | return total; | |
fbd162e6 YK |
2655 | } |
2656 | ||
f265e0e4 | 2657 | static void xbzrle_load_setup(void) |
56e93d26 | 2658 | { |
f265e0e4 | 2659 | XBZRLE.decoded_buf = g_malloc(TARGET_PAGE_SIZE); |
56e93d26 JQ |
2660 | } |
2661 | ||
f265e0e4 JQ |
2662 | static void xbzrle_load_cleanup(void) |
2663 | { | |
2664 | g_free(XBZRLE.decoded_buf); | |
2665 | XBZRLE.decoded_buf = NULL; | |
2666 | } | |
2667 | ||
7d7c96be PX |
2668 | static void ram_state_cleanup(RAMState **rsp) |
2669 | { | |
b9ccaf6d DDAG |
2670 | if (*rsp) { |
2671 | migration_page_queue_free(*rsp); | |
2672 | qemu_mutex_destroy(&(*rsp)->bitmap_mutex); | |
2673 | qemu_mutex_destroy(&(*rsp)->src_page_req_mutex); | |
2674 | g_free(*rsp); | |
2675 | *rsp = NULL; | |
2676 | } | |
7d7c96be PX |
2677 | } |
2678 | ||
84593a08 PX |
2679 | static void xbzrle_cleanup(void) |
2680 | { | |
2681 | XBZRLE_cache_lock(); | |
2682 | if (XBZRLE.cache) { | |
2683 | cache_fini(XBZRLE.cache); | |
2684 | g_free(XBZRLE.encoded_buf); | |
2685 | g_free(XBZRLE.current_buf); | |
2686 | g_free(XBZRLE.zero_target_page); | |
2687 | XBZRLE.cache = NULL; | |
2688 | XBZRLE.encoded_buf = NULL; | |
2689 | XBZRLE.current_buf = NULL; | |
2690 | XBZRLE.zero_target_page = NULL; | |
2691 | } | |
2692 | XBZRLE_cache_unlock(); | |
2693 | } | |
2694 | ||
f265e0e4 | 2695 | static void ram_save_cleanup(void *opaque) |
56e93d26 | 2696 | { |
53518d94 | 2697 | RAMState **rsp = opaque; |
6b6712ef | 2698 | RAMBlock *block; |
eb859c53 | 2699 | |
278e2f55 AG |
2700 | /* We don't use dirty log with background snapshots */ |
2701 | if (!migrate_background_snapshot()) { | |
2702 | /* caller have hold iothread lock or is in a bh, so there is | |
2703 | * no writing race against the migration bitmap | |
2704 | */ | |
63b41db4 HH |
2705 | if (global_dirty_tracking & GLOBAL_DIRTY_MIGRATION) { |
2706 | /* | |
2707 | * do not stop dirty log without starting it, since | |
2708 | * memory_global_dirty_log_stop will assert that | |
2709 | * memory_global_dirty_log_start/stop used in pairs | |
2710 | */ | |
2711 | memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION); | |
2712 | } | |
278e2f55 | 2713 | } |
6b6712ef | 2714 | |
fbd162e6 | 2715 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
002cad6b PX |
2716 | g_free(block->clear_bmap); |
2717 | block->clear_bmap = NULL; | |
6b6712ef JQ |
2718 | g_free(block->bmap); |
2719 | block->bmap = NULL; | |
56e93d26 JQ |
2720 | } |
2721 | ||
84593a08 | 2722 | xbzrle_cleanup(); |
f0afa331 | 2723 | compress_threads_save_cleanup(); |
7d7c96be | 2724 | ram_state_cleanup(rsp); |
4010ba38 JQ |
2725 | g_free(migration_ops); |
2726 | migration_ops = NULL; | |
56e93d26 JQ |
2727 | } |
2728 | ||
6f37bb8b | 2729 | static void ram_state_reset(RAMState *rs) |
56e93d26 | 2730 | { |
ec6f3ab9 PX |
2731 | int i; |
2732 | ||
2733 | for (i = 0; i < RAM_CHANNEL_MAX; i++) { | |
2734 | rs->pss[i].last_sent_block = NULL; | |
2735 | } | |
2736 | ||
6f37bb8b | 2737 | rs->last_seen_block = NULL; |
269ace29 | 2738 | rs->last_page = 0; |
6f37bb8b | 2739 | rs->last_version = ram_list.version; |
1a373522 | 2740 | rs->xbzrle_enabled = false; |
56e93d26 JQ |
2741 | } |
2742 | ||
2743 | #define MAX_WAIT 50 /* ms, half buffered_file limit */ | |
2744 | ||
e0b266f0 DDAG |
2745 | /* **** functions for postcopy ***** */ |
2746 | ||
ced1c616 PB |
2747 | void ram_postcopy_migrated_memory_release(MigrationState *ms) |
2748 | { | |
2749 | struct RAMBlock *block; | |
ced1c616 | 2750 | |
fbd162e6 | 2751 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
6b6712ef JQ |
2752 | unsigned long *bitmap = block->bmap; |
2753 | unsigned long range = block->used_length >> TARGET_PAGE_BITS; | |
2754 | unsigned long run_start = find_next_zero_bit(bitmap, range, 0); | |
ced1c616 PB |
2755 | |
2756 | while (run_start < range) { | |
2757 | unsigned long run_end = find_next_bit(bitmap, range, run_start + 1); | |
8bba004c AR |
2758 | ram_discard_range(block->idstr, |
2759 | ((ram_addr_t)run_start) << TARGET_PAGE_BITS, | |
2760 | ((ram_addr_t)(run_end - run_start)) | |
2761 | << TARGET_PAGE_BITS); | |
ced1c616 PB |
2762 | run_start = find_next_zero_bit(bitmap, range, run_end + 1); |
2763 | } | |
2764 | } | |
2765 | } | |
2766 | ||
3d0684b2 JQ |
2767 | /** |
2768 | * postcopy_send_discard_bm_ram: discard a RAMBlock | |
2769 | * | |
e0b266f0 | 2770 | * Callback from postcopy_each_ram_send_discard for each RAMBlock |
3d0684b2 JQ |
2771 | * |
2772 | * @ms: current migration state | |
89dab31b | 2773 | * @block: RAMBlock to discard |
e0b266f0 | 2774 | */ |
9e7d1223 | 2775 | static void postcopy_send_discard_bm_ram(MigrationState *ms, RAMBlock *block) |
e0b266f0 | 2776 | { |
6b6712ef | 2777 | unsigned long end = block->used_length >> TARGET_PAGE_BITS; |
e0b266f0 | 2778 | unsigned long current; |
1e7cf8c3 | 2779 | unsigned long *bitmap = block->bmap; |
e0b266f0 | 2780 | |
6b6712ef | 2781 | for (current = 0; current < end; ) { |
1e7cf8c3 | 2782 | unsigned long one = find_next_bit(bitmap, end, current); |
33a5cb62 | 2783 | unsigned long zero, discard_length; |
e0b266f0 | 2784 | |
33a5cb62 WY |
2785 | if (one >= end) { |
2786 | break; | |
2787 | } | |
e0b266f0 | 2788 | |
1e7cf8c3 | 2789 | zero = find_next_zero_bit(bitmap, end, one + 1); |
33a5cb62 WY |
2790 | |
2791 | if (zero >= end) { | |
2792 | discard_length = end - one; | |
e0b266f0 | 2793 | } else { |
33a5cb62 WY |
2794 | discard_length = zero - one; |
2795 | } | |
810cf2bb | 2796 | postcopy_discard_send_range(ms, one, discard_length); |
33a5cb62 | 2797 | current = one + discard_length; |
e0b266f0 | 2798 | } |
e0b266f0 DDAG |
2799 | } |
2800 | ||
f30c2e5b PX |
2801 | static void postcopy_chunk_hostpages_pass(MigrationState *ms, RAMBlock *block); |
2802 | ||
3d0684b2 JQ |
2803 | /** |
2804 | * postcopy_each_ram_send_discard: discard all RAMBlocks | |
2805 | * | |
e0b266f0 DDAG |
2806 | * Utility for the outgoing postcopy code. |
2807 | * Calls postcopy_send_discard_bm_ram for each RAMBlock | |
2808 | * passing it bitmap indexes and name. | |
e0b266f0 DDAG |
2809 | * (qemu_ram_foreach_block ends up passing unscaled lengths |
2810 | * which would mean postcopy code would have to deal with target page) | |
3d0684b2 JQ |
2811 | * |
2812 | * @ms: current migration state | |
e0b266f0 | 2813 | */ |
739fcc1b | 2814 | static void postcopy_each_ram_send_discard(MigrationState *ms) |
e0b266f0 DDAG |
2815 | { |
2816 | struct RAMBlock *block; | |
e0b266f0 | 2817 | |
fbd162e6 | 2818 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
810cf2bb | 2819 | postcopy_discard_send_init(ms, block->idstr); |
e0b266f0 | 2820 | |
f30c2e5b PX |
2821 | /* |
2822 | * Deal with TPS != HPS and huge pages. It discard any partially sent | |
2823 | * host-page size chunks, mark any partially dirty host-page size | |
2824 | * chunks as all dirty. In this case the host-page is the host-page | |
2825 | * for the particular RAMBlock, i.e. it might be a huge page. | |
2826 | */ | |
2827 | postcopy_chunk_hostpages_pass(ms, block); | |
2828 | ||
e0b266f0 DDAG |
2829 | /* |
2830 | * Postcopy sends chunks of bitmap over the wire, but it | |
2831 | * just needs indexes at this point, avoids it having | |
2832 | * target page specific code. | |
2833 | */ | |
739fcc1b | 2834 | postcopy_send_discard_bm_ram(ms, block); |
810cf2bb | 2835 | postcopy_discard_send_finish(ms); |
e0b266f0 | 2836 | } |
e0b266f0 DDAG |
2837 | } |
2838 | ||
3d0684b2 | 2839 | /** |
8324ef86 | 2840 | * postcopy_chunk_hostpages_pass: canonicalize bitmap in hostpages |
3d0684b2 JQ |
2841 | * |
2842 | * Helper for postcopy_chunk_hostpages; it's called twice to | |
2843 | * canonicalize the two bitmaps, that are similar, but one is | |
2844 | * inverted. | |
99e314eb | 2845 | * |
3d0684b2 JQ |
2846 | * Postcopy requires that all target pages in a hostpage are dirty or |
2847 | * clean, not a mix. This function canonicalizes the bitmaps. | |
99e314eb | 2848 | * |
3d0684b2 | 2849 | * @ms: current migration state |
3d0684b2 | 2850 | * @block: block that contains the page we want to canonicalize |
99e314eb | 2851 | */ |
1e7cf8c3 | 2852 | static void postcopy_chunk_hostpages_pass(MigrationState *ms, RAMBlock *block) |
99e314eb | 2853 | { |
53518d94 | 2854 | RAMState *rs = ram_state; |
6b6712ef | 2855 | unsigned long *bitmap = block->bmap; |
29c59172 | 2856 | unsigned int host_ratio = block->page_size / TARGET_PAGE_SIZE; |
6b6712ef | 2857 | unsigned long pages = block->used_length >> TARGET_PAGE_BITS; |
99e314eb DDAG |
2858 | unsigned long run_start; |
2859 | ||
29c59172 DDAG |
2860 | if (block->page_size == TARGET_PAGE_SIZE) { |
2861 | /* Easy case - TPS==HPS for a non-huge page RAMBlock */ | |
2862 | return; | |
2863 | } | |
2864 | ||
1e7cf8c3 WY |
2865 | /* Find a dirty page */ |
2866 | run_start = find_next_bit(bitmap, pages, 0); | |
99e314eb | 2867 | |
6b6712ef | 2868 | while (run_start < pages) { |
99e314eb DDAG |
2869 | |
2870 | /* | |
2871 | * If the start of this run of pages is in the middle of a host | |
2872 | * page, then we need to fixup this host page. | |
2873 | */ | |
9dec3cc3 | 2874 | if (QEMU_IS_ALIGNED(run_start, host_ratio)) { |
99e314eb | 2875 | /* Find the end of this run */ |
1e7cf8c3 | 2876 | run_start = find_next_zero_bit(bitmap, pages, run_start + 1); |
99e314eb DDAG |
2877 | /* |
2878 | * If the end isn't at the start of a host page, then the | |
2879 | * run doesn't finish at the end of a host page | |
2880 | * and we need to discard. | |
2881 | */ | |
99e314eb DDAG |
2882 | } |
2883 | ||
9dec3cc3 | 2884 | if (!QEMU_IS_ALIGNED(run_start, host_ratio)) { |
99e314eb | 2885 | unsigned long page; |
dad45ab2 WY |
2886 | unsigned long fixup_start_addr = QEMU_ALIGN_DOWN(run_start, |
2887 | host_ratio); | |
2888 | run_start = QEMU_ALIGN_UP(run_start, host_ratio); | |
99e314eb | 2889 | |
99e314eb DDAG |
2890 | /* Clean up the bitmap */ |
2891 | for (page = fixup_start_addr; | |
2892 | page < fixup_start_addr + host_ratio; page++) { | |
99e314eb DDAG |
2893 | /* |
2894 | * Remark them as dirty, updating the count for any pages | |
2895 | * that weren't previously dirty. | |
2896 | */ | |
0d8ec885 | 2897 | rs->migration_dirty_pages += !test_and_set_bit(page, bitmap); |
99e314eb DDAG |
2898 | } |
2899 | } | |
2900 | ||
1e7cf8c3 WY |
2901 | /* Find the next dirty page for the next iteration */ |
2902 | run_start = find_next_bit(bitmap, pages, run_start); | |
99e314eb DDAG |
2903 | } |
2904 | } | |
2905 | ||
3d0684b2 JQ |
2906 | /** |
2907 | * ram_postcopy_send_discard_bitmap: transmit the discard bitmap | |
2908 | * | |
e0b266f0 DDAG |
2909 | * Transmit the set of pages to be discarded after precopy to the target |
2910 | * these are pages that: | |
2911 | * a) Have been previously transmitted but are now dirty again | |
2912 | * b) Pages that have never been transmitted, this ensures that | |
2913 | * any pages on the destination that have been mapped by background | |
2914 | * tasks get discarded (transparent huge pages is the specific concern) | |
2915 | * Hopefully this is pretty sparse | |
3d0684b2 JQ |
2916 | * |
2917 | * @ms: current migration state | |
e0b266f0 | 2918 | */ |
739fcc1b | 2919 | void ram_postcopy_send_discard_bitmap(MigrationState *ms) |
e0b266f0 | 2920 | { |
53518d94 | 2921 | RAMState *rs = ram_state; |
e0b266f0 | 2922 | |
89ac5a1d | 2923 | RCU_READ_LOCK_GUARD(); |
e0b266f0 DDAG |
2924 | |
2925 | /* This should be our last sync, the src is now paused */ | |
eb859c53 | 2926 | migration_bitmap_sync(rs); |
e0b266f0 | 2927 | |
6b6712ef | 2928 | /* Easiest way to make sure we don't resume in the middle of a host-page */ |
ec6f3ab9 | 2929 | rs->pss[RAM_CHANNEL_PRECOPY].last_sent_block = NULL; |
6b6712ef | 2930 | rs->last_seen_block = NULL; |
6b6712ef | 2931 | rs->last_page = 0; |
e0b266f0 | 2932 | |
739fcc1b | 2933 | postcopy_each_ram_send_discard(ms); |
e0b266f0 | 2934 | |
739fcc1b | 2935 | trace_ram_postcopy_send_discard_bitmap(); |
e0b266f0 DDAG |
2936 | } |
2937 | ||
3d0684b2 JQ |
2938 | /** |
2939 | * ram_discard_range: discard dirtied pages at the beginning of postcopy | |
e0b266f0 | 2940 | * |
3d0684b2 | 2941 | * Returns zero on success |
e0b266f0 | 2942 | * |
36449157 JQ |
2943 | * @rbname: name of the RAMBlock of the request. NULL means the |
2944 | * same that last one. | |
3d0684b2 JQ |
2945 | * @start: RAMBlock starting page |
2946 | * @length: RAMBlock size | |
e0b266f0 | 2947 | */ |
aaa2064c | 2948 | int ram_discard_range(const char *rbname, uint64_t start, size_t length) |
e0b266f0 | 2949 | { |
36449157 | 2950 | trace_ram_discard_range(rbname, start, length); |
d3a5038c | 2951 | |
89ac5a1d | 2952 | RCU_READ_LOCK_GUARD(); |
36449157 | 2953 | RAMBlock *rb = qemu_ram_block_by_name(rbname); |
e0b266f0 DDAG |
2954 | |
2955 | if (!rb) { | |
36449157 | 2956 | error_report("ram_discard_range: Failed to find block '%s'", rbname); |
03acb4e9 | 2957 | return -1; |
e0b266f0 DDAG |
2958 | } |
2959 | ||
814bb08f PX |
2960 | /* |
2961 | * On source VM, we don't need to update the received bitmap since | |
2962 | * we don't even have one. | |
2963 | */ | |
2964 | if (rb->receivedmap) { | |
2965 | bitmap_clear(rb->receivedmap, start >> qemu_target_page_bits(), | |
2966 | length >> qemu_target_page_bits()); | |
2967 | } | |
2968 | ||
03acb4e9 | 2969 | return ram_block_discard_range(rb, start, length); |
e0b266f0 DDAG |
2970 | } |
2971 | ||
84593a08 PX |
2972 | /* |
2973 | * For every allocation, we will try not to crash the VM if the | |
2974 | * allocation failed. | |
2975 | */ | |
2976 | static int xbzrle_init(void) | |
2977 | { | |
2978 | Error *local_err = NULL; | |
2979 | ||
2980 | if (!migrate_use_xbzrle()) { | |
2981 | return 0; | |
2982 | } | |
2983 | ||
2984 | XBZRLE_cache_lock(); | |
2985 | ||
2986 | XBZRLE.zero_target_page = g_try_malloc0(TARGET_PAGE_SIZE); | |
2987 | if (!XBZRLE.zero_target_page) { | |
2988 | error_report("%s: Error allocating zero page", __func__); | |
2989 | goto err_out; | |
2990 | } | |
2991 | ||
2992 | XBZRLE.cache = cache_init(migrate_xbzrle_cache_size(), | |
2993 | TARGET_PAGE_SIZE, &local_err); | |
2994 | if (!XBZRLE.cache) { | |
2995 | error_report_err(local_err); | |
2996 | goto free_zero_page; | |
2997 | } | |
2998 | ||
2999 | XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); | |
3000 | if (!XBZRLE.encoded_buf) { | |
3001 | error_report("%s: Error allocating encoded_buf", __func__); | |
3002 | goto free_cache; | |
3003 | } | |
3004 | ||
3005 | XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); | |
3006 | if (!XBZRLE.current_buf) { | |
3007 | error_report("%s: Error allocating current_buf", __func__); | |
3008 | goto free_encoded_buf; | |
3009 | } | |
3010 | ||
3011 | /* We are all good */ | |
3012 | XBZRLE_cache_unlock(); | |
3013 | return 0; | |
3014 | ||
3015 | free_encoded_buf: | |
3016 | g_free(XBZRLE.encoded_buf); | |
3017 | XBZRLE.encoded_buf = NULL; | |
3018 | free_cache: | |
3019 | cache_fini(XBZRLE.cache); | |
3020 | XBZRLE.cache = NULL; | |
3021 | free_zero_page: | |
3022 | g_free(XBZRLE.zero_target_page); | |
3023 | XBZRLE.zero_target_page = NULL; | |
3024 | err_out: | |
3025 | XBZRLE_cache_unlock(); | |
3026 | return -ENOMEM; | |
3027 | } | |
3028 | ||
53518d94 | 3029 | static int ram_state_init(RAMState **rsp) |
56e93d26 | 3030 | { |
7d00ee6a PX |
3031 | *rsp = g_try_new0(RAMState, 1); |
3032 | ||
3033 | if (!*rsp) { | |
3034 | error_report("%s: Init ramstate fail", __func__); | |
3035 | return -1; | |
3036 | } | |
53518d94 JQ |
3037 | |
3038 | qemu_mutex_init(&(*rsp)->bitmap_mutex); | |
3039 | qemu_mutex_init(&(*rsp)->src_page_req_mutex); | |
3040 | QSIMPLEQ_INIT(&(*rsp)->src_page_requests); | |
8d80e195 | 3041 | (*rsp)->ram_bytes_total = ram_bytes_total(); |
56e93d26 | 3042 | |
7d00ee6a | 3043 | /* |
40c4d4a8 IR |
3044 | * Count the total number of pages used by ram blocks not including any |
3045 | * gaps due to alignment or unplugs. | |
03158519 | 3046 | * This must match with the initial values of dirty bitmap. |
7d00ee6a | 3047 | */ |
8d80e195 | 3048 | (*rsp)->migration_dirty_pages = (*rsp)->ram_bytes_total >> TARGET_PAGE_BITS; |
7d00ee6a PX |
3049 | ram_state_reset(*rsp); |
3050 | ||
3051 | return 0; | |
3052 | } | |
3053 | ||
d6eff5d7 | 3054 | static void ram_list_init_bitmaps(void) |
7d00ee6a | 3055 | { |
002cad6b | 3056 | MigrationState *ms = migrate_get_current(); |
d6eff5d7 PX |
3057 | RAMBlock *block; |
3058 | unsigned long pages; | |
002cad6b | 3059 | uint8_t shift; |
56e93d26 | 3060 | |
0827b9e9 AA |
3061 | /* Skip setting bitmap if there is no RAM */ |
3062 | if (ram_bytes_total()) { | |
002cad6b PX |
3063 | shift = ms->clear_bitmap_shift; |
3064 | if (shift > CLEAR_BITMAP_SHIFT_MAX) { | |
3065 | error_report("clear_bitmap_shift (%u) too big, using " | |
3066 | "max value (%u)", shift, CLEAR_BITMAP_SHIFT_MAX); | |
3067 | shift = CLEAR_BITMAP_SHIFT_MAX; | |
3068 | } else if (shift < CLEAR_BITMAP_SHIFT_MIN) { | |
3069 | error_report("clear_bitmap_shift (%u) too small, using " | |
3070 | "min value (%u)", shift, CLEAR_BITMAP_SHIFT_MIN); | |
3071 | shift = CLEAR_BITMAP_SHIFT_MIN; | |
3072 | } | |
3073 | ||
fbd162e6 | 3074 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
d6eff5d7 | 3075 | pages = block->max_length >> TARGET_PAGE_BITS; |
03158519 WY |
3076 | /* |
3077 | * The initial dirty bitmap for migration must be set with all | |
3078 | * ones to make sure we'll migrate every guest RAM page to | |
3079 | * destination. | |
40c4d4a8 IR |
3080 | * Here we set RAMBlock.bmap all to 1 because when rebegin a |
3081 | * new migration after a failed migration, ram_list. | |
3082 | * dirty_memory[DIRTY_MEMORY_MIGRATION] don't include the whole | |
3083 | * guest memory. | |
03158519 | 3084 | */ |
6b6712ef | 3085 | block->bmap = bitmap_new(pages); |
40c4d4a8 | 3086 | bitmap_set(block->bmap, 0, pages); |
002cad6b PX |
3087 | block->clear_bmap_shift = shift; |
3088 | block->clear_bmap = bitmap_new(clear_bmap_size(pages, shift)); | |
0827b9e9 | 3089 | } |
f3f491fc | 3090 | } |
d6eff5d7 PX |
3091 | } |
3092 | ||
be39b4cd DH |
3093 | static void migration_bitmap_clear_discarded_pages(RAMState *rs) |
3094 | { | |
3095 | unsigned long pages; | |
3096 | RAMBlock *rb; | |
3097 | ||
3098 | RCU_READ_LOCK_GUARD(); | |
3099 | ||
3100 | RAMBLOCK_FOREACH_NOT_IGNORED(rb) { | |
3101 | pages = ramblock_dirty_bitmap_clear_discarded_pages(rb); | |
3102 | rs->migration_dirty_pages -= pages; | |
3103 | } | |
3104 | } | |
3105 | ||
d6eff5d7 PX |
3106 | static void ram_init_bitmaps(RAMState *rs) |
3107 | { | |
3108 | /* For memory_global_dirty_log_start below. */ | |
3109 | qemu_mutex_lock_iothread(); | |
3110 | qemu_mutex_lock_ramlist(); | |
f3f491fc | 3111 | |
89ac5a1d DDAG |
3112 | WITH_RCU_READ_LOCK_GUARD() { |
3113 | ram_list_init_bitmaps(); | |
278e2f55 AG |
3114 | /* We don't use dirty log with background snapshots */ |
3115 | if (!migrate_background_snapshot()) { | |
63b41db4 | 3116 | memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION); |
278e2f55 AG |
3117 | migration_bitmap_sync_precopy(rs); |
3118 | } | |
89ac5a1d | 3119 | } |
56e93d26 | 3120 | qemu_mutex_unlock_ramlist(); |
49877834 | 3121 | qemu_mutex_unlock_iothread(); |
be39b4cd DH |
3122 | |
3123 | /* | |
3124 | * After an eventual first bitmap sync, fixup the initial bitmap | |
3125 | * containing all 1s to exclude any discarded pages from migration. | |
3126 | */ | |
3127 | migration_bitmap_clear_discarded_pages(rs); | |
d6eff5d7 PX |
3128 | } |
3129 | ||
3130 | static int ram_init_all(RAMState **rsp) | |
3131 | { | |
3132 | if (ram_state_init(rsp)) { | |
3133 | return -1; | |
3134 | } | |
3135 | ||
3136 | if (xbzrle_init()) { | |
3137 | ram_state_cleanup(rsp); | |
3138 | return -1; | |
3139 | } | |
3140 | ||
3141 | ram_init_bitmaps(*rsp); | |
a91246c9 HZ |
3142 | |
3143 | return 0; | |
3144 | } | |
3145 | ||
08614f34 PX |
3146 | static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out) |
3147 | { | |
3148 | RAMBlock *block; | |
3149 | uint64_t pages = 0; | |
3150 | ||
3151 | /* | |
3152 | * Postcopy is not using xbzrle/compression, so no need for that. | |
3153 | * Also, since source are already halted, we don't need to care | |
3154 | * about dirty page logging as well. | |
3155 | */ | |
3156 | ||
fbd162e6 | 3157 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
08614f34 PX |
3158 | pages += bitmap_count_one(block->bmap, |
3159 | block->used_length >> TARGET_PAGE_BITS); | |
3160 | } | |
3161 | ||
3162 | /* This may not be aligned with current bitmaps. Recalculate. */ | |
3163 | rs->migration_dirty_pages = pages; | |
3164 | ||
1a373522 | 3165 | ram_state_reset(rs); |
08614f34 PX |
3166 | |
3167 | /* Update RAMState cache of output QEMUFile */ | |
7f401b80 | 3168 | rs->pss[RAM_CHANNEL_PRECOPY].pss_channel = out; |
08614f34 PX |
3169 | |
3170 | trace_ram_state_resume_prepare(pages); | |
3171 | } | |
3172 | ||
6bcb05fc WW |
3173 | /* |
3174 | * This function clears bits of the free pages reported by the caller from the | |
3175 | * migration dirty bitmap. @addr is the host address corresponding to the | |
3176 | * start of the continuous guest free pages, and @len is the total bytes of | |
3177 | * those pages. | |
3178 | */ | |
3179 | void qemu_guest_free_page_hint(void *addr, size_t len) | |
3180 | { | |
3181 | RAMBlock *block; | |
3182 | ram_addr_t offset; | |
3183 | size_t used_len, start, npages; | |
3184 | MigrationState *s = migrate_get_current(); | |
3185 | ||
3186 | /* This function is currently expected to be used during live migration */ | |
3187 | if (!migration_is_setup_or_active(s->state)) { | |
3188 | return; | |
3189 | } | |
3190 | ||
3191 | for (; len > 0; len -= used_len, addr += used_len) { | |
3192 | block = qemu_ram_block_from_host(addr, false, &offset); | |
3193 | if (unlikely(!block || offset >= block->used_length)) { | |
3194 | /* | |
3195 | * The implementation might not support RAMBlock resize during | |
3196 | * live migration, but it could happen in theory with future | |
3197 | * updates. So we add a check here to capture that case. | |
3198 | */ | |
3199 | error_report_once("%s unexpected error", __func__); | |
3200 | return; | |
3201 | } | |
3202 | ||
3203 | if (len <= block->used_length - offset) { | |
3204 | used_len = len; | |
3205 | } else { | |
3206 | used_len = block->used_length - offset; | |
3207 | } | |
3208 | ||
3209 | start = offset >> TARGET_PAGE_BITS; | |
3210 | npages = used_len >> TARGET_PAGE_BITS; | |
3211 | ||
3212 | qemu_mutex_lock(&ram_state->bitmap_mutex); | |
3143577d WW |
3213 | /* |
3214 | * The skipped free pages are equavalent to be sent from clear_bmap's | |
3215 | * perspective, so clear the bits from the memory region bitmap which | |
3216 | * are initially set. Otherwise those skipped pages will be sent in | |
3217 | * the next round after syncing from the memory region bitmap. | |
3218 | */ | |
1230a25f | 3219 | migration_clear_memory_region_dirty_bitmap_range(block, start, npages); |
6bcb05fc WW |
3220 | ram_state->migration_dirty_pages -= |
3221 | bitmap_count_one_with_offset(block->bmap, start, npages); | |
3222 | bitmap_clear(block->bmap, start, npages); | |
3223 | qemu_mutex_unlock(&ram_state->bitmap_mutex); | |
3224 | } | |
3225 | } | |
3226 | ||
3d0684b2 JQ |
3227 | /* |
3228 | * Each of ram_save_setup, ram_save_iterate and ram_save_complete has | |
a91246c9 HZ |
3229 | * long-running RCU critical section. When rcu-reclaims in the code |
3230 | * start to become numerous it will be necessary to reduce the | |
3231 | * granularity of these critical sections. | |
3232 | */ | |
3233 | ||
3d0684b2 JQ |
3234 | /** |
3235 | * ram_save_setup: Setup RAM for migration | |
3236 | * | |
3237 | * Returns zero to indicate success and negative for error | |
3238 | * | |
3239 | * @f: QEMUFile where to send the data | |
3240 | * @opaque: RAMState pointer | |
3241 | */ | |
a91246c9 HZ |
3242 | static int ram_save_setup(QEMUFile *f, void *opaque) |
3243 | { | |
53518d94 | 3244 | RAMState **rsp = opaque; |
a91246c9 | 3245 | RAMBlock *block; |
33d70973 | 3246 | int ret; |
a91246c9 | 3247 | |
dcaf446e XG |
3248 | if (compress_threads_save_setup()) { |
3249 | return -1; | |
3250 | } | |
3251 | ||
a91246c9 HZ |
3252 | /* migration has already setup the bitmap, reuse it. */ |
3253 | if (!migration_in_colo_state()) { | |
7d00ee6a | 3254 | if (ram_init_all(rsp) != 0) { |
dcaf446e | 3255 | compress_threads_save_cleanup(); |
a91246c9 | 3256 | return -1; |
53518d94 | 3257 | } |
a91246c9 | 3258 | } |
7f401b80 | 3259 | (*rsp)->pss[RAM_CHANNEL_PRECOPY].pss_channel = f; |
a91246c9 | 3260 | |
0e6ebd48 | 3261 | WITH_RCU_READ_LOCK_GUARD() { |
8008a272 JQ |
3262 | qemu_put_be64(f, ram_bytes_total_with_ignored() |
3263 | | RAM_SAVE_FLAG_MEM_SIZE); | |
56e93d26 | 3264 | |
0e6ebd48 DDAG |
3265 | RAMBLOCK_FOREACH_MIGRATABLE(block) { |
3266 | qemu_put_byte(f, strlen(block->idstr)); | |
3267 | qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); | |
3268 | qemu_put_be64(f, block->used_length); | |
3269 | if (migrate_postcopy_ram() && block->page_size != | |
3270 | qemu_host_page_size) { | |
3271 | qemu_put_be64(f, block->page_size); | |
3272 | } | |
3273 | if (migrate_ignore_shared()) { | |
3274 | qemu_put_be64(f, block->mr->addr); | |
3275 | } | |
fbd162e6 | 3276 | } |
56e93d26 JQ |
3277 | } |
3278 | ||
56e93d26 JQ |
3279 | ram_control_before_iterate(f, RAM_CONTROL_SETUP); |
3280 | ram_control_after_iterate(f, RAM_CONTROL_SETUP); | |
3281 | ||
4010ba38 JQ |
3282 | migration_ops = g_malloc0(sizeof(MigrationOps)); |
3283 | migration_ops->ram_save_target_page = ram_save_target_page_legacy; | |
8ebb6ecc | 3284 | ret = multifd_send_sync_main(f); |
33d70973 LB |
3285 | if (ret < 0) { |
3286 | return ret; | |
3287 | } | |
3288 | ||
56e93d26 | 3289 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
35374cbd | 3290 | qemu_fflush(f); |
56e93d26 JQ |
3291 | |
3292 | return 0; | |
3293 | } | |
3294 | ||
3d0684b2 JQ |
3295 | /** |
3296 | * ram_save_iterate: iterative stage for migration | |
3297 | * | |
3298 | * Returns zero to indicate success and negative for error | |
3299 | * | |
3300 | * @f: QEMUFile where to send the data | |
3301 | * @opaque: RAMState pointer | |
3302 | */ | |
56e93d26 JQ |
3303 | static int ram_save_iterate(QEMUFile *f, void *opaque) |
3304 | { | |
53518d94 JQ |
3305 | RAMState **temp = opaque; |
3306 | RAMState *rs = *temp; | |
3d4095b2 | 3307 | int ret = 0; |
56e93d26 JQ |
3308 | int i; |
3309 | int64_t t0; | |
5c90308f | 3310 | int done = 0; |
56e93d26 | 3311 | |
b2557345 PL |
3312 | if (blk_mig_bulk_active()) { |
3313 | /* Avoid transferring ram during bulk phase of block migration as | |
3314 | * the bulk phase will usually take a long time and transferring | |
3315 | * ram updates during that time is pointless. */ | |
3316 | goto out; | |
3317 | } | |
3318 | ||
63268c49 PX |
3319 | /* |
3320 | * We'll take this lock a little bit long, but it's okay for two reasons. | |
3321 | * Firstly, the only possible other thread to take it is who calls | |
3322 | * qemu_guest_free_page_hint(), which should be rare; secondly, see | |
3323 | * MAX_WAIT (if curious, further see commit 4508bd9ed8053ce) below, which | |
3324 | * guarantees that we'll at least released it in a regular basis. | |
3325 | */ | |
3326 | qemu_mutex_lock(&rs->bitmap_mutex); | |
89ac5a1d DDAG |
3327 | WITH_RCU_READ_LOCK_GUARD() { |
3328 | if (ram_list.version != rs->last_version) { | |
3329 | ram_state_reset(rs); | |
3330 | } | |
56e93d26 | 3331 | |
89ac5a1d DDAG |
3332 | /* Read version before ram_list.blocks */ |
3333 | smp_rmb(); | |
56e93d26 | 3334 | |
89ac5a1d | 3335 | ram_control_before_iterate(f, RAM_CONTROL_ROUND); |
56e93d26 | 3336 | |
89ac5a1d DDAG |
3337 | t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); |
3338 | i = 0; | |
3339 | while ((ret = qemu_file_rate_limit(f)) == 0 || | |
a1fe28df | 3340 | postcopy_has_request(rs)) { |
89ac5a1d | 3341 | int pages; |
e03a34f8 | 3342 | |
89ac5a1d DDAG |
3343 | if (qemu_file_get_error(f)) { |
3344 | break; | |
3345 | } | |
e8f3735f | 3346 | |
05931ec5 | 3347 | pages = ram_find_and_save_block(rs); |
89ac5a1d DDAG |
3348 | /* no more pages to sent */ |
3349 | if (pages == 0) { | |
3350 | done = 1; | |
3351 | break; | |
3352 | } | |
e8f3735f | 3353 | |
89ac5a1d DDAG |
3354 | if (pages < 0) { |
3355 | qemu_file_set_error(f, pages); | |
56e93d26 JQ |
3356 | break; |
3357 | } | |
89ac5a1d DDAG |
3358 | |
3359 | rs->target_page_count += pages; | |
3360 | ||
644acf99 WY |
3361 | /* |
3362 | * During postcopy, it is necessary to make sure one whole host | |
3363 | * page is sent in one chunk. | |
3364 | */ | |
3365 | if (migrate_postcopy_ram()) { | |
3366 | flush_compressed_data(rs); | |
3367 | } | |
3368 | ||
89ac5a1d DDAG |
3369 | /* |
3370 | * we want to check in the 1st loop, just in case it was the 1st | |
3371 | * time and we had to sync the dirty bitmap. | |
3372 | * qemu_clock_get_ns() is a bit expensive, so we only check each | |
3373 | * some iterations | |
3374 | */ | |
3375 | if ((i & 63) == 0) { | |
3376 | uint64_t t1 = (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - t0) / | |
3377 | 1000000; | |
3378 | if (t1 > MAX_WAIT) { | |
3379 | trace_ram_save_iterate_big_wait(t1, i); | |
3380 | break; | |
3381 | } | |
3382 | } | |
3383 | i++; | |
56e93d26 | 3384 | } |
56e93d26 | 3385 | } |
63268c49 | 3386 | qemu_mutex_unlock(&rs->bitmap_mutex); |
56e93d26 JQ |
3387 | |
3388 | /* | |
3389 | * Must occur before EOS (or any QEMUFile operation) | |
3390 | * because of RDMA protocol. | |
3391 | */ | |
3392 | ram_control_after_iterate(f, RAM_CONTROL_ROUND); | |
3393 | ||
b2557345 | 3394 | out: |
b69a0227 JQ |
3395 | if (ret >= 0 |
3396 | && migration_is_setup_or_active(migrate_get_current()->state)) { | |
7f401b80 | 3397 | ret = multifd_send_sync_main(rs->pss[RAM_CHANNEL_PRECOPY].pss_channel); |
33d70973 LB |
3398 | if (ret < 0) { |
3399 | return ret; | |
3400 | } | |
3401 | ||
3d4095b2 JQ |
3402 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); |
3403 | qemu_fflush(f); | |
4c2d0f6d | 3404 | ram_transferred_add(8); |
56e93d26 | 3405 | |
3d4095b2 JQ |
3406 | ret = qemu_file_get_error(f); |
3407 | } | |
56e93d26 JQ |
3408 | if (ret < 0) { |
3409 | return ret; | |
3410 | } | |
3411 | ||
5c90308f | 3412 | return done; |
56e93d26 JQ |
3413 | } |
3414 | ||
3d0684b2 JQ |
3415 | /** |
3416 | * ram_save_complete: function called to send the remaining amount of ram | |
3417 | * | |
e8f3735f | 3418 | * Returns zero to indicate success or negative on error |
3d0684b2 JQ |
3419 | * |
3420 | * Called with iothread lock | |
3421 | * | |
3422 | * @f: QEMUFile where to send the data | |
3423 | * @opaque: RAMState pointer | |
3424 | */ | |
56e93d26 JQ |
3425 | static int ram_save_complete(QEMUFile *f, void *opaque) |
3426 | { | |
53518d94 JQ |
3427 | RAMState **temp = opaque; |
3428 | RAMState *rs = *temp; | |
e8f3735f | 3429 | int ret = 0; |
6f37bb8b | 3430 | |
05931ec5 JQ |
3431 | rs->last_stage = !migration_in_colo_state(); |
3432 | ||
89ac5a1d DDAG |
3433 | WITH_RCU_READ_LOCK_GUARD() { |
3434 | if (!migration_in_postcopy()) { | |
3435 | migration_bitmap_sync_precopy(rs); | |
3436 | } | |
56e93d26 | 3437 | |
89ac5a1d | 3438 | ram_control_before_iterate(f, RAM_CONTROL_FINISH); |
56e93d26 | 3439 | |
89ac5a1d | 3440 | /* try transferring iterative blocks of memory */ |
56e93d26 | 3441 | |
89ac5a1d | 3442 | /* flush all remaining blocks regardless of rate limiting */ |
c13221b5 | 3443 | qemu_mutex_lock(&rs->bitmap_mutex); |
89ac5a1d DDAG |
3444 | while (true) { |
3445 | int pages; | |
56e93d26 | 3446 | |
05931ec5 | 3447 | pages = ram_find_and_save_block(rs); |
89ac5a1d DDAG |
3448 | /* no more blocks to sent */ |
3449 | if (pages == 0) { | |
3450 | break; | |
3451 | } | |
3452 | if (pages < 0) { | |
3453 | ret = pages; | |
3454 | break; | |
3455 | } | |
e8f3735f | 3456 | } |
c13221b5 | 3457 | qemu_mutex_unlock(&rs->bitmap_mutex); |
56e93d26 | 3458 | |
89ac5a1d DDAG |
3459 | flush_compressed_data(rs); |
3460 | ram_control_after_iterate(f, RAM_CONTROL_FINISH); | |
3461 | } | |
d09a6fde | 3462 | |
33d70973 LB |
3463 | if (ret < 0) { |
3464 | return ret; | |
3d4095b2 | 3465 | } |
56e93d26 | 3466 | |
7f401b80 | 3467 | ret = multifd_send_sync_main(rs->pss[RAM_CHANNEL_PRECOPY].pss_channel); |
33d70973 LB |
3468 | if (ret < 0) { |
3469 | return ret; | |
3470 | } | |
3471 | ||
3472 | qemu_put_be64(f, RAM_SAVE_FLAG_EOS); | |
3473 | qemu_fflush(f); | |
3474 | ||
3475 | return 0; | |
56e93d26 JQ |
3476 | } |
3477 | ||
24beea4e JQ |
3478 | static void ram_state_pending_estimate(void *opaque, uint64_t *must_precopy, |
3479 | uint64_t *can_postcopy) | |
56e93d26 | 3480 | { |
53518d94 JQ |
3481 | RAMState **temp = opaque; |
3482 | RAMState *rs = *temp; | |
56e93d26 | 3483 | |
c8df4a7a | 3484 | uint64_t remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE; |
56e93d26 | 3485 | |
c8df4a7a JQ |
3486 | if (migrate_postcopy_ram()) { |
3487 | /* We can do postcopy, and all the data is postcopiable */ | |
24beea4e | 3488 | *can_postcopy += remaining_size; |
c8df4a7a | 3489 | } else { |
24beea4e | 3490 | *must_precopy += remaining_size; |
c8df4a7a JQ |
3491 | } |
3492 | } | |
3493 | ||
24beea4e JQ |
3494 | static void ram_state_pending_exact(void *opaque, uint64_t *must_precopy, |
3495 | uint64_t *can_postcopy) | |
c8df4a7a | 3496 | { |
28ef5339 | 3497 | MigrationState *s = migrate_get_current(); |
c8df4a7a JQ |
3498 | RAMState **temp = opaque; |
3499 | RAMState *rs = *temp; | |
3500 | ||
3501 | uint64_t remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE; | |
3502 | ||
28ef5339 | 3503 | if (!migration_in_postcopy() && remaining_size < s->threshold_size) { |
56e93d26 | 3504 | qemu_mutex_lock_iothread(); |
89ac5a1d DDAG |
3505 | WITH_RCU_READ_LOCK_GUARD() { |
3506 | migration_bitmap_sync_precopy(rs); | |
3507 | } | |
56e93d26 | 3508 | qemu_mutex_unlock_iothread(); |
9edabd4d | 3509 | remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE; |
56e93d26 | 3510 | } |
c31b098f | 3511 | |
86e1167e VSO |
3512 | if (migrate_postcopy_ram()) { |
3513 | /* We can do postcopy, and all the data is postcopiable */ | |
24beea4e | 3514 | *can_postcopy += remaining_size; |
86e1167e | 3515 | } else { |
24beea4e | 3516 | *must_precopy += remaining_size; |
86e1167e | 3517 | } |
56e93d26 JQ |
3518 | } |
3519 | ||
3520 | static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) | |
3521 | { | |
3522 | unsigned int xh_len; | |
3523 | int xh_flags; | |
063e760a | 3524 | uint8_t *loaded_data; |
56e93d26 | 3525 | |
56e93d26 JQ |
3526 | /* extract RLE header */ |
3527 | xh_flags = qemu_get_byte(f); | |
3528 | xh_len = qemu_get_be16(f); | |
3529 | ||
3530 | if (xh_flags != ENCODING_FLAG_XBZRLE) { | |
3531 | error_report("Failed to load XBZRLE page - wrong compression!"); | |
3532 | return -1; | |
3533 | } | |
3534 | ||
3535 | if (xh_len > TARGET_PAGE_SIZE) { | |
3536 | error_report("Failed to load XBZRLE page - len overflow!"); | |
3537 | return -1; | |
3538 | } | |
f265e0e4 | 3539 | loaded_data = XBZRLE.decoded_buf; |
56e93d26 | 3540 | /* load data and decode */ |
f265e0e4 | 3541 | /* it can change loaded_data to point to an internal buffer */ |
063e760a | 3542 | qemu_get_buffer_in_place(f, &loaded_data, xh_len); |
56e93d26 JQ |
3543 | |
3544 | /* decode RLE */ | |
063e760a | 3545 | if (xbzrle_decode_buffer(loaded_data, xh_len, host, |
56e93d26 JQ |
3546 | TARGET_PAGE_SIZE) == -1) { |
3547 | error_report("Failed to load XBZRLE page - decode error!"); | |
3548 | return -1; | |
3549 | } | |
3550 | ||
3551 | return 0; | |
3552 | } | |
3553 | ||
3d0684b2 JQ |
3554 | /** |
3555 | * ram_block_from_stream: read a RAMBlock id from the migration stream | |
3556 | * | |
3557 | * Must be called from within a rcu critical section. | |
3558 | * | |
56e93d26 | 3559 | * Returns a pointer from within the RCU-protected ram_list. |
a7180877 | 3560 | * |
755e8d7c | 3561 | * @mis: the migration incoming state pointer |
3d0684b2 JQ |
3562 | * @f: QEMUFile where to read the data from |
3563 | * @flags: Page flags (mostly to see if it's a continuation of previous block) | |
c01b16ed | 3564 | * @channel: the channel we're using |
a7180877 | 3565 | */ |
755e8d7c | 3566 | static inline RAMBlock *ram_block_from_stream(MigrationIncomingState *mis, |
c01b16ed PX |
3567 | QEMUFile *f, int flags, |
3568 | int channel) | |
56e93d26 | 3569 | { |
c01b16ed | 3570 | RAMBlock *block = mis->last_recv_block[channel]; |
56e93d26 JQ |
3571 | char id[256]; |
3572 | uint8_t len; | |
3573 | ||
3574 | if (flags & RAM_SAVE_FLAG_CONTINUE) { | |
4c4bad48 | 3575 | if (!block) { |
56e93d26 JQ |
3576 | error_report("Ack, bad migration stream!"); |
3577 | return NULL; | |
3578 | } | |
4c4bad48 | 3579 | return block; |
56e93d26 JQ |
3580 | } |
3581 | ||
3582 | len = qemu_get_byte(f); | |
3583 | qemu_get_buffer(f, (uint8_t *)id, len); | |
3584 | id[len] = 0; | |
3585 | ||
e3dd7493 | 3586 | block = qemu_ram_block_by_name(id); |
4c4bad48 HZ |
3587 | if (!block) { |
3588 | error_report("Can't find block %s", id); | |
3589 | return NULL; | |
56e93d26 JQ |
3590 | } |
3591 | ||
fbd162e6 | 3592 | if (ramblock_is_ignored(block)) { |
b895de50 CLG |
3593 | error_report("block %s should not be migrated !", id); |
3594 | return NULL; | |
3595 | } | |
3596 | ||
c01b16ed | 3597 | mis->last_recv_block[channel] = block; |
755e8d7c | 3598 | |
4c4bad48 HZ |
3599 | return block; |
3600 | } | |
3601 | ||
3602 | static inline void *host_from_ram_block_offset(RAMBlock *block, | |
3603 | ram_addr_t offset) | |
3604 | { | |
3605 | if (!offset_in_ramblock(block, offset)) { | |
3606 | return NULL; | |
3607 | } | |
3608 | ||
3609 | return block->host + offset; | |
56e93d26 JQ |
3610 | } |
3611 | ||
6a23f639 DH |
3612 | static void *host_page_from_ram_block_offset(RAMBlock *block, |
3613 | ram_addr_t offset) | |
3614 | { | |
3615 | /* Note: Explicitly no check against offset_in_ramblock(). */ | |
3616 | return (void *)QEMU_ALIGN_DOWN((uintptr_t)(block->host + offset), | |
3617 | block->page_size); | |
3618 | } | |
3619 | ||
3620 | static ram_addr_t host_page_offset_from_ram_block_offset(RAMBlock *block, | |
3621 | ram_addr_t offset) | |
3622 | { | |
3623 | return ((uintptr_t)block->host + offset) & (block->page_size - 1); | |
3624 | } | |
3625 | ||
13af18f2 | 3626 | static inline void *colo_cache_from_block_offset(RAMBlock *block, |
8af66371 | 3627 | ram_addr_t offset, bool record_bitmap) |
13af18f2 ZC |
3628 | { |
3629 | if (!offset_in_ramblock(block, offset)) { | |
3630 | return NULL; | |
3631 | } | |
3632 | if (!block->colo_cache) { | |
3633 | error_report("%s: colo_cache is NULL in block :%s", | |
3634 | __func__, block->idstr); | |
3635 | return NULL; | |
3636 | } | |
7d9acafa ZC |
3637 | |
3638 | /* | |
3639 | * During colo checkpoint, we need bitmap of these migrated pages. | |
3640 | * It help us to decide which pages in ram cache should be flushed | |
3641 | * into VM's RAM later. | |
3642 | */ | |
8af66371 HZ |
3643 | if (record_bitmap && |
3644 | !test_and_set_bit(offset >> TARGET_PAGE_BITS, block->bmap)) { | |
7d9acafa ZC |
3645 | ram_state->migration_dirty_pages++; |
3646 | } | |
13af18f2 ZC |
3647 | return block->colo_cache + offset; |
3648 | } | |
3649 | ||
3d0684b2 JQ |
3650 | /** |
3651 | * ram_handle_compressed: handle the zero page case | |
3652 | * | |
56e93d26 JQ |
3653 | * If a page (or a whole RDMA chunk) has been |
3654 | * determined to be zero, then zap it. | |
3d0684b2 JQ |
3655 | * |
3656 | * @host: host address for the zero page | |
3657 | * @ch: what the page is filled from. We only support zero | |
3658 | * @size: size of the zero page | |
56e93d26 JQ |
3659 | */ |
3660 | void ram_handle_compressed(void *host, uint8_t ch, uint64_t size) | |
3661 | { | |
bad452a7 | 3662 | if (ch != 0 || !buffer_is_zero(host, size)) { |
56e93d26 JQ |
3663 | memset(host, ch, size); |
3664 | } | |
3665 | } | |
3666 | ||
797ca154 XG |
3667 | /* return the size after decompression, or negative value on error */ |
3668 | static int | |
3669 | qemu_uncompress_data(z_stream *stream, uint8_t *dest, size_t dest_len, | |
3670 | const uint8_t *source, size_t source_len) | |
3671 | { | |
3672 | int err; | |
3673 | ||
3674 | err = inflateReset(stream); | |
3675 | if (err != Z_OK) { | |
3676 | return -1; | |
3677 | } | |
3678 | ||
3679 | stream->avail_in = source_len; | |
3680 | stream->next_in = (uint8_t *)source; | |
3681 | stream->avail_out = dest_len; | |
3682 | stream->next_out = dest; | |
3683 | ||
3684 | err = inflate(stream, Z_NO_FLUSH); | |
3685 | if (err != Z_STREAM_END) { | |
3686 | return -1; | |
3687 | } | |
3688 | ||
3689 | return stream->total_out; | |
3690 | } | |
3691 | ||
56e93d26 JQ |
3692 | static void *do_data_decompress(void *opaque) |
3693 | { | |
3694 | DecompressParam *param = opaque; | |
3695 | unsigned long pagesize; | |
33d151f4 | 3696 | uint8_t *des; |
34ab9e97 | 3697 | int len, ret; |
56e93d26 | 3698 | |
33d151f4 | 3699 | qemu_mutex_lock(¶m->mutex); |
90e56fb4 | 3700 | while (!param->quit) { |
33d151f4 LL |
3701 | if (param->des) { |
3702 | des = param->des; | |
3703 | len = param->len; | |
3704 | param->des = 0; | |
3705 | qemu_mutex_unlock(¶m->mutex); | |
3706 | ||
56e93d26 | 3707 | pagesize = TARGET_PAGE_SIZE; |
34ab9e97 XG |
3708 | |
3709 | ret = qemu_uncompress_data(¶m->stream, des, pagesize, | |
3710 | param->compbuf, len); | |
f548222c | 3711 | if (ret < 0 && migrate_get_current()->decompress_error_check) { |
34ab9e97 XG |
3712 | error_report("decompress data failed"); |
3713 | qemu_file_set_error(decomp_file, ret); | |
3714 | } | |
73a8912b | 3715 | |
33d151f4 LL |
3716 | qemu_mutex_lock(&decomp_done_lock); |
3717 | param->done = true; | |
3718 | qemu_cond_signal(&decomp_done_cond); | |
3719 | qemu_mutex_unlock(&decomp_done_lock); | |
3720 | ||
3721 | qemu_mutex_lock(¶m->mutex); | |
3722 | } else { | |
3723 | qemu_cond_wait(¶m->cond, ¶m->mutex); | |
3724 | } | |
56e93d26 | 3725 | } |
33d151f4 | 3726 | qemu_mutex_unlock(¶m->mutex); |
56e93d26 JQ |
3727 | |
3728 | return NULL; | |
3729 | } | |
3730 | ||
34ab9e97 | 3731 | static int wait_for_decompress_done(void) |
5533b2e9 LL |
3732 | { |
3733 | int idx, thread_count; | |
3734 | ||
3735 | if (!migrate_use_compression()) { | |
34ab9e97 | 3736 | return 0; |
5533b2e9 LL |
3737 | } |
3738 | ||
3739 | thread_count = migrate_decompress_threads(); | |
3740 | qemu_mutex_lock(&decomp_done_lock); | |
3741 | for (idx = 0; idx < thread_count; idx++) { | |
3742 | while (!decomp_param[idx].done) { | |
3743 | qemu_cond_wait(&decomp_done_cond, &decomp_done_lock); | |
3744 | } | |
3745 | } | |
3746 | qemu_mutex_unlock(&decomp_done_lock); | |
34ab9e97 | 3747 | return qemu_file_get_error(decomp_file); |
5533b2e9 LL |
3748 | } |
3749 | ||
f0afa331 | 3750 | static void compress_threads_load_cleanup(void) |
56e93d26 JQ |
3751 | { |
3752 | int i, thread_count; | |
3753 | ||
3416ab5b JQ |
3754 | if (!migrate_use_compression()) { |
3755 | return; | |
3756 | } | |
56e93d26 JQ |
3757 | thread_count = migrate_decompress_threads(); |
3758 | for (i = 0; i < thread_count; i++) { | |
797ca154 XG |
3759 | /* |
3760 | * we use it as a indicator which shows if the thread is | |
3761 | * properly init'd or not | |
3762 | */ | |
3763 | if (!decomp_param[i].compbuf) { | |
3764 | break; | |
3765 | } | |
3766 | ||
56e93d26 | 3767 | qemu_mutex_lock(&decomp_param[i].mutex); |
90e56fb4 | 3768 | decomp_param[i].quit = true; |
56e93d26 JQ |
3769 | qemu_cond_signal(&decomp_param[i].cond); |
3770 | qemu_mutex_unlock(&decomp_param[i].mutex); | |
3771 | } | |
3772 | for (i = 0; i < thread_count; i++) { | |
797ca154 XG |
3773 | if (!decomp_param[i].compbuf) { |
3774 | break; | |
3775 | } | |
3776 | ||
56e93d26 JQ |
3777 | qemu_thread_join(decompress_threads + i); |
3778 | qemu_mutex_destroy(&decomp_param[i].mutex); | |
3779 | qemu_cond_destroy(&decomp_param[i].cond); | |
797ca154 | 3780 | inflateEnd(&decomp_param[i].stream); |
56e93d26 | 3781 | g_free(decomp_param[i].compbuf); |
797ca154 | 3782 | decomp_param[i].compbuf = NULL; |
56e93d26 JQ |
3783 | } |
3784 | g_free(decompress_threads); | |
3785 | g_free(decomp_param); | |
56e93d26 JQ |
3786 | decompress_threads = NULL; |
3787 | decomp_param = NULL; | |
34ab9e97 | 3788 | decomp_file = NULL; |
56e93d26 JQ |
3789 | } |
3790 | ||
34ab9e97 | 3791 | static int compress_threads_load_setup(QEMUFile *f) |
797ca154 XG |
3792 | { |
3793 | int i, thread_count; | |
3794 | ||
3795 | if (!migrate_use_compression()) { | |
3796 | return 0; | |
3797 | } | |
3798 | ||
3799 | thread_count = migrate_decompress_threads(); | |
3800 | decompress_threads = g_new0(QemuThread, thread_count); | |
3801 | decomp_param = g_new0(DecompressParam, thread_count); | |
3802 | qemu_mutex_init(&decomp_done_lock); | |
3803 | qemu_cond_init(&decomp_done_cond); | |
34ab9e97 | 3804 | decomp_file = f; |
797ca154 XG |
3805 | for (i = 0; i < thread_count; i++) { |
3806 | if (inflateInit(&decomp_param[i].stream) != Z_OK) { | |
3807 | goto exit; | |
3808 | } | |
3809 | ||
3810 | decomp_param[i].compbuf = g_malloc0(compressBound(TARGET_PAGE_SIZE)); | |
3811 | qemu_mutex_init(&decomp_param[i].mutex); | |
3812 | qemu_cond_init(&decomp_param[i].cond); | |
3813 | decomp_param[i].done = true; | |
3814 | decomp_param[i].quit = false; | |
3815 | qemu_thread_create(decompress_threads + i, "decompress", | |
3816 | do_data_decompress, decomp_param + i, | |
3817 | QEMU_THREAD_JOINABLE); | |
3818 | } | |
3819 | return 0; | |
3820 | exit: | |
3821 | compress_threads_load_cleanup(); | |
3822 | return -1; | |
3823 | } | |
3824 | ||
c1bc6626 | 3825 | static void decompress_data_with_multi_threads(QEMUFile *f, |
56e93d26 JQ |
3826 | void *host, int len) |
3827 | { | |
3828 | int idx, thread_count; | |
3829 | ||
3830 | thread_count = migrate_decompress_threads(); | |
37396950 | 3831 | QEMU_LOCK_GUARD(&decomp_done_lock); |
56e93d26 JQ |
3832 | while (true) { |
3833 | for (idx = 0; idx < thread_count; idx++) { | |
73a8912b | 3834 | if (decomp_param[idx].done) { |
33d151f4 LL |
3835 | decomp_param[idx].done = false; |
3836 | qemu_mutex_lock(&decomp_param[idx].mutex); | |
c1bc6626 | 3837 | qemu_get_buffer(f, decomp_param[idx].compbuf, len); |
56e93d26 JQ |
3838 | decomp_param[idx].des = host; |
3839 | decomp_param[idx].len = len; | |
33d151f4 LL |
3840 | qemu_cond_signal(&decomp_param[idx].cond); |
3841 | qemu_mutex_unlock(&decomp_param[idx].mutex); | |
56e93d26 JQ |
3842 | break; |
3843 | } | |
3844 | } | |
3845 | if (idx < thread_count) { | |
3846 | break; | |
73a8912b LL |
3847 | } else { |
3848 | qemu_cond_wait(&decomp_done_cond, &decomp_done_lock); | |
56e93d26 JQ |
3849 | } |
3850 | } | |
3851 | } | |
3852 | ||
b70cb3b4 RL |
3853 | static void colo_init_ram_state(void) |
3854 | { | |
3855 | ram_state_init(&ram_state); | |
b70cb3b4 RL |
3856 | } |
3857 | ||
13af18f2 ZC |
3858 | /* |
3859 | * colo cache: this is for secondary VM, we cache the whole | |
3860 | * memory of the secondary VM, it is need to hold the global lock | |
3861 | * to call this helper. | |
3862 | */ | |
3863 | int colo_init_ram_cache(void) | |
3864 | { | |
3865 | RAMBlock *block; | |
3866 | ||
44901b5a PB |
3867 | WITH_RCU_READ_LOCK_GUARD() { |
3868 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
3869 | block->colo_cache = qemu_anon_ram_alloc(block->used_length, | |
8dbe22c6 | 3870 | NULL, false, false); |
44901b5a PB |
3871 | if (!block->colo_cache) { |
3872 | error_report("%s: Can't alloc memory for COLO cache of block %s," | |
3873 | "size 0x" RAM_ADDR_FMT, __func__, block->idstr, | |
3874 | block->used_length); | |
3875 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
3876 | if (block->colo_cache) { | |
3877 | qemu_anon_ram_free(block->colo_cache, block->used_length); | |
3878 | block->colo_cache = NULL; | |
3879 | } | |
89ac5a1d | 3880 | } |
44901b5a | 3881 | return -errno; |
89ac5a1d | 3882 | } |
e5fdf920 LS |
3883 | if (!machine_dump_guest_core(current_machine)) { |
3884 | qemu_madvise(block->colo_cache, block->used_length, | |
3885 | QEMU_MADV_DONTDUMP); | |
3886 | } | |
13af18f2 | 3887 | } |
13af18f2 | 3888 | } |
44901b5a | 3889 | |
7d9acafa ZC |
3890 | /* |
3891 | * Record the dirty pages that sent by PVM, we use this dirty bitmap together | |
3892 | * with to decide which page in cache should be flushed into SVM's RAM. Here | |
3893 | * we use the same name 'ram_bitmap' as for migration. | |
3894 | */ | |
3895 | if (ram_bytes_total()) { | |
3896 | RAMBlock *block; | |
3897 | ||
fbd162e6 | 3898 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
7d9acafa | 3899 | unsigned long pages = block->max_length >> TARGET_PAGE_BITS; |
7d9acafa | 3900 | block->bmap = bitmap_new(pages); |
7d9acafa ZC |
3901 | } |
3902 | } | |
7d9acafa | 3903 | |
b70cb3b4 | 3904 | colo_init_ram_state(); |
13af18f2 | 3905 | return 0; |
13af18f2 ZC |
3906 | } |
3907 | ||
0393031a HZ |
3908 | /* TODO: duplicated with ram_init_bitmaps */ |
3909 | void colo_incoming_start_dirty_log(void) | |
3910 | { | |
3911 | RAMBlock *block = NULL; | |
3912 | /* For memory_global_dirty_log_start below. */ | |
3913 | qemu_mutex_lock_iothread(); | |
3914 | qemu_mutex_lock_ramlist(); | |
3915 | ||
3916 | memory_global_dirty_log_sync(); | |
3917 | WITH_RCU_READ_LOCK_GUARD() { | |
3918 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
3919 | ramblock_sync_dirty_bitmap(ram_state, block); | |
3920 | /* Discard this dirty bitmap record */ | |
3921 | bitmap_zero(block->bmap, block->max_length >> TARGET_PAGE_BITS); | |
3922 | } | |
63b41db4 | 3923 | memory_global_dirty_log_start(GLOBAL_DIRTY_MIGRATION); |
0393031a HZ |
3924 | } |
3925 | ram_state->migration_dirty_pages = 0; | |
3926 | qemu_mutex_unlock_ramlist(); | |
3927 | qemu_mutex_unlock_iothread(); | |
3928 | } | |
3929 | ||
13af18f2 ZC |
3930 | /* It is need to hold the global lock to call this helper */ |
3931 | void colo_release_ram_cache(void) | |
3932 | { | |
3933 | RAMBlock *block; | |
3934 | ||
63b41db4 | 3935 | memory_global_dirty_log_stop(GLOBAL_DIRTY_MIGRATION); |
fbd162e6 | 3936 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
7d9acafa ZC |
3937 | g_free(block->bmap); |
3938 | block->bmap = NULL; | |
3939 | } | |
3940 | ||
89ac5a1d DDAG |
3941 | WITH_RCU_READ_LOCK_GUARD() { |
3942 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
3943 | if (block->colo_cache) { | |
3944 | qemu_anon_ram_free(block->colo_cache, block->used_length); | |
3945 | block->colo_cache = NULL; | |
3946 | } | |
13af18f2 ZC |
3947 | } |
3948 | } | |
0393031a | 3949 | ram_state_cleanup(&ram_state); |
13af18f2 ZC |
3950 | } |
3951 | ||
f265e0e4 JQ |
3952 | /** |
3953 | * ram_load_setup: Setup RAM for migration incoming side | |
3954 | * | |
3955 | * Returns zero to indicate success and negative for error | |
3956 | * | |
3957 | * @f: QEMUFile where to receive the data | |
3958 | * @opaque: RAMState pointer | |
3959 | */ | |
3960 | static int ram_load_setup(QEMUFile *f, void *opaque) | |
3961 | { | |
34ab9e97 | 3962 | if (compress_threads_load_setup(f)) { |
797ca154 XG |
3963 | return -1; |
3964 | } | |
3965 | ||
f265e0e4 | 3966 | xbzrle_load_setup(); |
f9494614 | 3967 | ramblock_recv_map_init(); |
13af18f2 | 3968 | |
f265e0e4 JQ |
3969 | return 0; |
3970 | } | |
3971 | ||
3972 | static int ram_load_cleanup(void *opaque) | |
3973 | { | |
f9494614 | 3974 | RAMBlock *rb; |
56eb90af | 3975 | |
fbd162e6 | 3976 | RAMBLOCK_FOREACH_NOT_IGNORED(rb) { |
bd108a44 | 3977 | qemu_ram_block_writeback(rb); |
56eb90af JH |
3978 | } |
3979 | ||
f265e0e4 | 3980 | xbzrle_load_cleanup(); |
f0afa331 | 3981 | compress_threads_load_cleanup(); |
f9494614 | 3982 | |
fbd162e6 | 3983 | RAMBLOCK_FOREACH_NOT_IGNORED(rb) { |
f9494614 AP |
3984 | g_free(rb->receivedmap); |
3985 | rb->receivedmap = NULL; | |
3986 | } | |
13af18f2 | 3987 | |
f265e0e4 JQ |
3988 | return 0; |
3989 | } | |
3990 | ||
3d0684b2 JQ |
3991 | /** |
3992 | * ram_postcopy_incoming_init: allocate postcopy data structures | |
3993 | * | |
3994 | * Returns 0 for success and negative if there was one error | |
3995 | * | |
3996 | * @mis: current migration incoming state | |
3997 | * | |
3998 | * Allocate data structures etc needed by incoming migration with | |
3999 | * postcopy-ram. postcopy-ram's similarly names | |
4000 | * postcopy_ram_incoming_init does the work. | |
1caddf8a DDAG |
4001 | */ |
4002 | int ram_postcopy_incoming_init(MigrationIncomingState *mis) | |
4003 | { | |
c136180c | 4004 | return postcopy_ram_incoming_init(mis); |
1caddf8a DDAG |
4005 | } |
4006 | ||
3d0684b2 JQ |
4007 | /** |
4008 | * ram_load_postcopy: load a page in postcopy case | |
4009 | * | |
4010 | * Returns 0 for success or -errno in case of error | |
4011 | * | |
a7180877 DDAG |
4012 | * Called in postcopy mode by ram_load(). |
4013 | * rcu_read_lock is taken prior to this being called. | |
3d0684b2 JQ |
4014 | * |
4015 | * @f: QEMUFile where to send the data | |
36f62f11 | 4016 | * @channel: the channel to use for loading |
a7180877 | 4017 | */ |
36f62f11 | 4018 | int ram_load_postcopy(QEMUFile *f, int channel) |
a7180877 DDAG |
4019 | { |
4020 | int flags = 0, ret = 0; | |
4021 | bool place_needed = false; | |
1aa83678 | 4022 | bool matches_target_page_size = false; |
a7180877 | 4023 | MigrationIncomingState *mis = migration_incoming_get_current(); |
36f62f11 | 4024 | PostcopyTmpPage *tmp_page = &mis->postcopy_tmp_pages[channel]; |
a7180877 DDAG |
4025 | |
4026 | while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { | |
4027 | ram_addr_t addr; | |
a7180877 DDAG |
4028 | void *page_buffer = NULL; |
4029 | void *place_source = NULL; | |
df9ff5e1 | 4030 | RAMBlock *block = NULL; |
a7180877 | 4031 | uint8_t ch; |
644acf99 | 4032 | int len; |
a7180877 DDAG |
4033 | |
4034 | addr = qemu_get_be64(f); | |
7a9ddfbf PX |
4035 | |
4036 | /* | |
4037 | * If qemu file error, we should stop here, and then "addr" | |
4038 | * may be invalid | |
4039 | */ | |
4040 | ret = qemu_file_get_error(f); | |
4041 | if (ret) { | |
4042 | break; | |
4043 | } | |
4044 | ||
a7180877 DDAG |
4045 | flags = addr & ~TARGET_PAGE_MASK; |
4046 | addr &= TARGET_PAGE_MASK; | |
4047 | ||
36f62f11 | 4048 | trace_ram_load_postcopy_loop(channel, (uint64_t)addr, flags); |
644acf99 WY |
4049 | if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE | |
4050 | RAM_SAVE_FLAG_COMPRESS_PAGE)) { | |
c01b16ed | 4051 | block = ram_block_from_stream(mis, f, flags, channel); |
6a23f639 DH |
4052 | if (!block) { |
4053 | ret = -EINVAL; | |
4054 | break; | |
4055 | } | |
4c4bad48 | 4056 | |
898ba906 DH |
4057 | /* |
4058 | * Relying on used_length is racy and can result in false positives. | |
4059 | * We might place pages beyond used_length in case RAM was shrunk | |
4060 | * while in postcopy, which is fine - trying to place via | |
4061 | * UFFDIO_COPY/UFFDIO_ZEROPAGE will never segfault. | |
4062 | */ | |
4063 | if (!block->host || addr >= block->postcopy_length) { | |
a7180877 DDAG |
4064 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); |
4065 | ret = -EINVAL; | |
4066 | break; | |
4067 | } | |
77dadc3f | 4068 | tmp_page->target_pages++; |
1aa83678 | 4069 | matches_target_page_size = block->page_size == TARGET_PAGE_SIZE; |
a7180877 | 4070 | /* |
28abd200 DDAG |
4071 | * Postcopy requires that we place whole host pages atomically; |
4072 | * these may be huge pages for RAMBlocks that are backed by | |
4073 | * hugetlbfs. | |
a7180877 DDAG |
4074 | * To make it atomic, the data is read into a temporary page |
4075 | * that's moved into place later. | |
4076 | * The migration protocol uses, possibly smaller, target-pages | |
4077 | * however the source ensures it always sends all the components | |
91ba442f | 4078 | * of a host page in one chunk. |
a7180877 | 4079 | */ |
77dadc3f | 4080 | page_buffer = tmp_page->tmp_huge_page + |
6a23f639 DH |
4081 | host_page_offset_from_ram_block_offset(block, addr); |
4082 | /* If all TP are zero then we can optimise the place */ | |
77dadc3f PX |
4083 | if (tmp_page->target_pages == 1) { |
4084 | tmp_page->host_addr = | |
4085 | host_page_from_ram_block_offset(block, addr); | |
4086 | } else if (tmp_page->host_addr != | |
4087 | host_page_from_ram_block_offset(block, addr)) { | |
c53b7ddc | 4088 | /* not the 1st TP within the HP */ |
36f62f11 | 4089 | error_report("Non-same host page detected on channel %d: " |
cfc7dc8a PX |
4090 | "Target host page %p, received host page %p " |
4091 | "(rb %s offset 0x"RAM_ADDR_FMT" target_pages %d)", | |
36f62f11 | 4092 | channel, tmp_page->host_addr, |
cfc7dc8a PX |
4093 | host_page_from_ram_block_offset(block, addr), |
4094 | block->idstr, addr, tmp_page->target_pages); | |
6a23f639 DH |
4095 | ret = -EINVAL; |
4096 | break; | |
a7180877 DDAG |
4097 | } |
4098 | ||
4099 | /* | |
4100 | * If it's the last part of a host page then we place the host | |
4101 | * page | |
4102 | */ | |
77dadc3f PX |
4103 | if (tmp_page->target_pages == |
4104 | (block->page_size / TARGET_PAGE_SIZE)) { | |
4cbb3c63 | 4105 | place_needed = true; |
4cbb3c63 | 4106 | } |
77dadc3f | 4107 | place_source = tmp_page->tmp_huge_page; |
a7180877 DDAG |
4108 | } |
4109 | ||
4110 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { | |
bb890ed5 | 4111 | case RAM_SAVE_FLAG_ZERO: |
a7180877 | 4112 | ch = qemu_get_byte(f); |
2e36bc1b WY |
4113 | /* |
4114 | * Can skip to set page_buffer when | |
4115 | * this is a zero page and (block->page_size == TARGET_PAGE_SIZE). | |
4116 | */ | |
4117 | if (ch || !matches_target_page_size) { | |
4118 | memset(page_buffer, ch, TARGET_PAGE_SIZE); | |
4119 | } | |
a7180877 | 4120 | if (ch) { |
77dadc3f | 4121 | tmp_page->all_zero = false; |
a7180877 DDAG |
4122 | } |
4123 | break; | |
4124 | ||
4125 | case RAM_SAVE_FLAG_PAGE: | |
77dadc3f | 4126 | tmp_page->all_zero = false; |
1aa83678 PX |
4127 | if (!matches_target_page_size) { |
4128 | /* For huge pages, we always use temporary buffer */ | |
a7180877 DDAG |
4129 | qemu_get_buffer(f, page_buffer, TARGET_PAGE_SIZE); |
4130 | } else { | |
1aa83678 PX |
4131 | /* |
4132 | * For small pages that matches target page size, we | |
4133 | * avoid the qemu_file copy. Instead we directly use | |
4134 | * the buffer of QEMUFile to place the page. Note: we | |
4135 | * cannot do any QEMUFile operation before using that | |
4136 | * buffer to make sure the buffer is valid when | |
4137 | * placing the page. | |
a7180877 DDAG |
4138 | */ |
4139 | qemu_get_buffer_in_place(f, (uint8_t **)&place_source, | |
4140 | TARGET_PAGE_SIZE); | |
4141 | } | |
4142 | break; | |
644acf99 | 4143 | case RAM_SAVE_FLAG_COMPRESS_PAGE: |
77dadc3f | 4144 | tmp_page->all_zero = false; |
644acf99 WY |
4145 | len = qemu_get_be32(f); |
4146 | if (len < 0 || len > compressBound(TARGET_PAGE_SIZE)) { | |
4147 | error_report("Invalid compressed data length: %d", len); | |
4148 | ret = -EINVAL; | |
4149 | break; | |
4150 | } | |
4151 | decompress_data_with_multi_threads(f, page_buffer, len); | |
4152 | break; | |
4153 | ||
a7180877 DDAG |
4154 | case RAM_SAVE_FLAG_EOS: |
4155 | /* normal exit */ | |
6df264ac | 4156 | multifd_recv_sync_main(); |
a7180877 DDAG |
4157 | break; |
4158 | default: | |
29fccade | 4159 | error_report("Unknown combination of migration flags: 0x%x" |
a7180877 DDAG |
4160 | " (postcopy mode)", flags); |
4161 | ret = -EINVAL; | |
7a9ddfbf PX |
4162 | break; |
4163 | } | |
4164 | ||
644acf99 WY |
4165 | /* Got the whole host page, wait for decompress before placing. */ |
4166 | if (place_needed) { | |
4167 | ret |= wait_for_decompress_done(); | |
4168 | } | |
4169 | ||
7a9ddfbf PX |
4170 | /* Detect for any possible file errors */ |
4171 | if (!ret && qemu_file_get_error(f)) { | |
4172 | ret = qemu_file_get_error(f); | |
a7180877 DDAG |
4173 | } |
4174 | ||
7a9ddfbf | 4175 | if (!ret && place_needed) { |
77dadc3f PX |
4176 | if (tmp_page->all_zero) { |
4177 | ret = postcopy_place_page_zero(mis, tmp_page->host_addr, block); | |
a7180877 | 4178 | } else { |
77dadc3f PX |
4179 | ret = postcopy_place_page(mis, tmp_page->host_addr, |
4180 | place_source, block); | |
a7180877 | 4181 | } |
ddf35bdf | 4182 | place_needed = false; |
77dadc3f | 4183 | postcopy_temp_page_reset(tmp_page); |
a7180877 | 4184 | } |
a7180877 DDAG |
4185 | } |
4186 | ||
4187 | return ret; | |
4188 | } | |
4189 | ||
acab30b8 DHB |
4190 | static bool postcopy_is_running(void) |
4191 | { | |
4192 | PostcopyState ps = postcopy_state_get(); | |
4193 | return ps >= POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_END; | |
4194 | } | |
4195 | ||
e6f4aa18 ZC |
4196 | /* |
4197 | * Flush content of RAM cache into SVM's memory. | |
4198 | * Only flush the pages that be dirtied by PVM or SVM or both. | |
4199 | */ | |
24fa16f8 | 4200 | void colo_flush_ram_cache(void) |
e6f4aa18 ZC |
4201 | { |
4202 | RAMBlock *block = NULL; | |
4203 | void *dst_host; | |
4204 | void *src_host; | |
4205 | unsigned long offset = 0; | |
4206 | ||
d1955d22 | 4207 | memory_global_dirty_log_sync(); |
89ac5a1d DDAG |
4208 | WITH_RCU_READ_LOCK_GUARD() { |
4209 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { | |
4210 | ramblock_sync_dirty_bitmap(ram_state, block); | |
4211 | } | |
d1955d22 | 4212 | } |
d1955d22 | 4213 | |
e6f4aa18 | 4214 | trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages); |
89ac5a1d DDAG |
4215 | WITH_RCU_READ_LOCK_GUARD() { |
4216 | block = QLIST_FIRST_RCU(&ram_list.blocks); | |
e6f4aa18 | 4217 | |
89ac5a1d | 4218 | while (block) { |
a6a83cef | 4219 | unsigned long num = 0; |
e6f4aa18 | 4220 | |
a6a83cef | 4221 | offset = colo_bitmap_find_dirty(ram_state, block, offset, &num); |
542147f4 DH |
4222 | if (!offset_in_ramblock(block, |
4223 | ((ram_addr_t)offset) << TARGET_PAGE_BITS)) { | |
89ac5a1d | 4224 | offset = 0; |
a6a83cef | 4225 | num = 0; |
89ac5a1d DDAG |
4226 | block = QLIST_NEXT_RCU(block, next); |
4227 | } else { | |
a6a83cef RL |
4228 | unsigned long i = 0; |
4229 | ||
4230 | for (i = 0; i < num; i++) { | |
4231 | migration_bitmap_clear_dirty(ram_state, block, offset + i); | |
4232 | } | |
8bba004c AR |
4233 | dst_host = block->host |
4234 | + (((ram_addr_t)offset) << TARGET_PAGE_BITS); | |
4235 | src_host = block->colo_cache | |
4236 | + (((ram_addr_t)offset) << TARGET_PAGE_BITS); | |
a6a83cef RL |
4237 | memcpy(dst_host, src_host, TARGET_PAGE_SIZE * num); |
4238 | offset += num; | |
89ac5a1d | 4239 | } |
e6f4aa18 ZC |
4240 | } |
4241 | } | |
e6f4aa18 ZC |
4242 | trace_colo_flush_ram_cache_end(); |
4243 | } | |
4244 | ||
10da4a36 WY |
4245 | /** |
4246 | * ram_load_precopy: load pages in precopy case | |
4247 | * | |
4248 | * Returns 0 for success or -errno in case of error | |
4249 | * | |
4250 | * Called in precopy mode by ram_load(). | |
4251 | * rcu_read_lock is taken prior to this being called. | |
4252 | * | |
4253 | * @f: QEMUFile where to send the data | |
4254 | */ | |
4255 | static int ram_load_precopy(QEMUFile *f) | |
56e93d26 | 4256 | { |
755e8d7c | 4257 | MigrationIncomingState *mis = migration_incoming_get_current(); |
e65cec5e | 4258 | int flags = 0, ret = 0, invalid_flags = 0, len = 0, i = 0; |
ef08fb38 | 4259 | /* ADVISE is earlier, it shows the source has the postcopy capability on */ |
80fe315c | 4260 | bool postcopy_advised = migration_incoming_postcopy_advised(); |
edc60127 JQ |
4261 | if (!migrate_use_compression()) { |
4262 | invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE; | |
4263 | } | |
a7180877 | 4264 | |
10da4a36 | 4265 | while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { |
56e93d26 | 4266 | ram_addr_t addr, total_ram_bytes; |
0393031a | 4267 | void *host = NULL, *host_bak = NULL; |
56e93d26 JQ |
4268 | uint8_t ch; |
4269 | ||
e65cec5e YK |
4270 | /* |
4271 | * Yield periodically to let main loop run, but an iteration of | |
4272 | * the main loop is expensive, so do it each some iterations | |
4273 | */ | |
4274 | if ((i & 32767) == 0 && qemu_in_coroutine()) { | |
4275 | aio_co_schedule(qemu_get_current_aio_context(), | |
4276 | qemu_coroutine_self()); | |
4277 | qemu_coroutine_yield(); | |
4278 | } | |
4279 | i++; | |
4280 | ||
56e93d26 JQ |
4281 | addr = qemu_get_be64(f); |
4282 | flags = addr & ~TARGET_PAGE_MASK; | |
4283 | addr &= TARGET_PAGE_MASK; | |
4284 | ||
edc60127 JQ |
4285 | if (flags & invalid_flags) { |
4286 | if (flags & invalid_flags & RAM_SAVE_FLAG_COMPRESS_PAGE) { | |
4287 | error_report("Received an unexpected compressed page"); | |
4288 | } | |
4289 | ||
4290 | ret = -EINVAL; | |
4291 | break; | |
4292 | } | |
4293 | ||
bb890ed5 | 4294 | if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE | |
a776aa15 | 4295 | RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) { |
c01b16ed PX |
4296 | RAMBlock *block = ram_block_from_stream(mis, f, flags, |
4297 | RAM_CHANNEL_PRECOPY); | |
4c4bad48 | 4298 | |
0393031a | 4299 | host = host_from_ram_block_offset(block, addr); |
13af18f2 | 4300 | /* |
0393031a HZ |
4301 | * After going into COLO stage, we should not load the page |
4302 | * into SVM's memory directly, we put them into colo_cache firstly. | |
4303 | * NOTE: We need to keep a copy of SVM's ram in colo_cache. | |
4304 | * Previously, we copied all these memory in preparing stage of COLO | |
4305 | * while we need to stop VM, which is a time-consuming process. | |
4306 | * Here we optimize it by a trick, back-up every page while in | |
4307 | * migration process while COLO is enabled, though it affects the | |
4308 | * speed of the migration, but it obviously reduce the downtime of | |
4309 | * back-up all SVM'S memory in COLO preparing stage. | |
13af18f2 | 4310 | */ |
0393031a HZ |
4311 | if (migration_incoming_colo_enabled()) { |
4312 | if (migration_incoming_in_colo_state()) { | |
4313 | /* In COLO stage, put all pages into cache temporarily */ | |
8af66371 | 4314 | host = colo_cache_from_block_offset(block, addr, true); |
0393031a HZ |
4315 | } else { |
4316 | /* | |
4317 | * In migration stage but before COLO stage, | |
4318 | * Put all pages into both cache and SVM's memory. | |
4319 | */ | |
8af66371 | 4320 | host_bak = colo_cache_from_block_offset(block, addr, false); |
0393031a | 4321 | } |
13af18f2 | 4322 | } |
a776aa15 DDAG |
4323 | if (!host) { |
4324 | error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); | |
4325 | ret = -EINVAL; | |
4326 | break; | |
4327 | } | |
13af18f2 ZC |
4328 | if (!migration_incoming_in_colo_state()) { |
4329 | ramblock_recv_bitmap_set(block, host); | |
4330 | } | |
4331 | ||
1db9d8e5 | 4332 | trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host); |
a776aa15 DDAG |
4333 | } |
4334 | ||
56e93d26 JQ |
4335 | switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { |
4336 | case RAM_SAVE_FLAG_MEM_SIZE: | |
4337 | /* Synchronize RAM block list */ | |
4338 | total_ram_bytes = addr; | |
4339 | while (!ret && total_ram_bytes) { | |
4340 | RAMBlock *block; | |
56e93d26 JQ |
4341 | char id[256]; |
4342 | ram_addr_t length; | |
4343 | ||
4344 | len = qemu_get_byte(f); | |
4345 | qemu_get_buffer(f, (uint8_t *)id, len); | |
4346 | id[len] = 0; | |
4347 | length = qemu_get_be64(f); | |
4348 | ||
e3dd7493 | 4349 | block = qemu_ram_block_by_name(id); |
b895de50 CLG |
4350 | if (block && !qemu_ram_is_migratable(block)) { |
4351 | error_report("block %s should not be migrated !", id); | |
4352 | ret = -EINVAL; | |
4353 | } else if (block) { | |
e3dd7493 DDAG |
4354 | if (length != block->used_length) { |
4355 | Error *local_err = NULL; | |
56e93d26 | 4356 | |
fa53a0e5 | 4357 | ret = qemu_ram_resize(block, length, |
e3dd7493 DDAG |
4358 | &local_err); |
4359 | if (local_err) { | |
4360 | error_report_err(local_err); | |
56e93d26 | 4361 | } |
56e93d26 | 4362 | } |
ef08fb38 | 4363 | /* For postcopy we need to check hugepage sizes match */ |
e846b746 | 4364 | if (postcopy_advised && migrate_postcopy_ram() && |
ef08fb38 DDAG |
4365 | block->page_size != qemu_host_page_size) { |
4366 | uint64_t remote_page_size = qemu_get_be64(f); | |
4367 | if (remote_page_size != block->page_size) { | |
4368 | error_report("Mismatched RAM page size %s " | |
4369 | "(local) %zd != %" PRId64, | |
4370 | id, block->page_size, | |
4371 | remote_page_size); | |
4372 | ret = -EINVAL; | |
4373 | } | |
4374 | } | |
fbd162e6 YK |
4375 | if (migrate_ignore_shared()) { |
4376 | hwaddr addr = qemu_get_be64(f); | |
fbd162e6 YK |
4377 | if (ramblock_is_ignored(block) && |
4378 | block->mr->addr != addr) { | |
4379 | error_report("Mismatched GPAs for block %s " | |
4380 | "%" PRId64 "!= %" PRId64, | |
4381 | id, (uint64_t)addr, | |
4382 | (uint64_t)block->mr->addr); | |
4383 | ret = -EINVAL; | |
4384 | } | |
4385 | } | |
e3dd7493 DDAG |
4386 | ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG, |
4387 | block->idstr); | |
4388 | } else { | |
56e93d26 JQ |
4389 | error_report("Unknown ramblock \"%s\", cannot " |
4390 | "accept migration", id); | |
4391 | ret = -EINVAL; | |
4392 | } | |
4393 | ||
4394 | total_ram_bytes -= length; | |
4395 | } | |
4396 | break; | |
a776aa15 | 4397 | |
bb890ed5 | 4398 | case RAM_SAVE_FLAG_ZERO: |
56e93d26 JQ |
4399 | ch = qemu_get_byte(f); |
4400 | ram_handle_compressed(host, ch, TARGET_PAGE_SIZE); | |
4401 | break; | |
a776aa15 | 4402 | |
56e93d26 | 4403 | case RAM_SAVE_FLAG_PAGE: |
56e93d26 JQ |
4404 | qemu_get_buffer(f, host, TARGET_PAGE_SIZE); |
4405 | break; | |
56e93d26 | 4406 | |
a776aa15 | 4407 | case RAM_SAVE_FLAG_COMPRESS_PAGE: |
56e93d26 JQ |
4408 | len = qemu_get_be32(f); |
4409 | if (len < 0 || len > compressBound(TARGET_PAGE_SIZE)) { | |
4410 | error_report("Invalid compressed data length: %d", len); | |
4411 | ret = -EINVAL; | |
4412 | break; | |
4413 | } | |
c1bc6626 | 4414 | decompress_data_with_multi_threads(f, host, len); |
56e93d26 | 4415 | break; |
a776aa15 | 4416 | |
56e93d26 | 4417 | case RAM_SAVE_FLAG_XBZRLE: |
56e93d26 JQ |
4418 | if (load_xbzrle(f, addr, host) < 0) { |
4419 | error_report("Failed to decompress XBZRLE page at " | |
4420 | RAM_ADDR_FMT, addr); | |
4421 | ret = -EINVAL; | |
4422 | break; | |
4423 | } | |
4424 | break; | |
4425 | case RAM_SAVE_FLAG_EOS: | |
4426 | /* normal exit */ | |
6df264ac | 4427 | multifd_recv_sync_main(); |
56e93d26 JQ |
4428 | break; |
4429 | default: | |
4430 | if (flags & RAM_SAVE_FLAG_HOOK) { | |
632e3a5c | 4431 | ram_control_load_hook(f, RAM_CONTROL_HOOK, NULL); |
56e93d26 | 4432 | } else { |
29fccade | 4433 | error_report("Unknown combination of migration flags: 0x%x", |
56e93d26 JQ |
4434 | flags); |
4435 | ret = -EINVAL; | |
4436 | } | |
4437 | } | |
4438 | if (!ret) { | |
4439 | ret = qemu_file_get_error(f); | |
4440 | } | |
0393031a HZ |
4441 | if (!ret && host_bak) { |
4442 | memcpy(host_bak, host, TARGET_PAGE_SIZE); | |
4443 | } | |
56e93d26 JQ |
4444 | } |
4445 | ||
ca1a6b70 | 4446 | ret |= wait_for_decompress_done(); |
10da4a36 WY |
4447 | return ret; |
4448 | } | |
4449 | ||
4450 | static int ram_load(QEMUFile *f, void *opaque, int version_id) | |
4451 | { | |
4452 | int ret = 0; | |
4453 | static uint64_t seq_iter; | |
4454 | /* | |
4455 | * If system is running in postcopy mode, page inserts to host memory must | |
4456 | * be atomic | |
4457 | */ | |
4458 | bool postcopy_running = postcopy_is_running(); | |
4459 | ||
4460 | seq_iter++; | |
4461 | ||
4462 | if (version_id != 4) { | |
4463 | return -EINVAL; | |
4464 | } | |
4465 | ||
4466 | /* | |
4467 | * This RCU critical section can be very long running. | |
4468 | * When RCU reclaims in the code start to become numerous, | |
4469 | * it will be necessary to reduce the granularity of this | |
4470 | * critical section. | |
4471 | */ | |
89ac5a1d DDAG |
4472 | WITH_RCU_READ_LOCK_GUARD() { |
4473 | if (postcopy_running) { | |
36f62f11 PX |
4474 | /* |
4475 | * Note! Here RAM_CHANNEL_PRECOPY is the precopy channel of | |
4476 | * postcopy migration, we have another RAM_CHANNEL_POSTCOPY to | |
4477 | * service fast page faults. | |
4478 | */ | |
4479 | ret = ram_load_postcopy(f, RAM_CHANNEL_PRECOPY); | |
89ac5a1d DDAG |
4480 | } else { |
4481 | ret = ram_load_precopy(f); | |
4482 | } | |
10da4a36 | 4483 | } |
55c4446b | 4484 | trace_ram_load_complete(ret, seq_iter); |
e6f4aa18 | 4485 | |
56e93d26 JQ |
4486 | return ret; |
4487 | } | |
4488 | ||
c6467627 VSO |
4489 | static bool ram_has_postcopy(void *opaque) |
4490 | { | |
469dd51b | 4491 | RAMBlock *rb; |
fbd162e6 | 4492 | RAMBLOCK_FOREACH_NOT_IGNORED(rb) { |
469dd51b JH |
4493 | if (ramblock_is_pmem(rb)) { |
4494 | info_report("Block: %s, host: %p is a nvdimm memory, postcopy" | |
4495 | "is not supported now!", rb->idstr, rb->host); | |
4496 | return false; | |
4497 | } | |
4498 | } | |
4499 | ||
c6467627 VSO |
4500 | return migrate_postcopy_ram(); |
4501 | } | |
4502 | ||
edd090c7 PX |
4503 | /* Sync all the dirty bitmap with destination VM. */ |
4504 | static int ram_dirty_bitmap_sync_all(MigrationState *s, RAMState *rs) | |
4505 | { | |
4506 | RAMBlock *block; | |
4507 | QEMUFile *file = s->to_dst_file; | |
4508 | int ramblock_count = 0; | |
4509 | ||
4510 | trace_ram_dirty_bitmap_sync_start(); | |
4511 | ||
fbd162e6 | 4512 | RAMBLOCK_FOREACH_NOT_IGNORED(block) { |
edd090c7 PX |
4513 | qemu_savevm_send_recv_bitmap(file, block->idstr); |
4514 | trace_ram_dirty_bitmap_request(block->idstr); | |
4515 | ramblock_count++; | |
4516 | } | |
4517 | ||
4518 | trace_ram_dirty_bitmap_sync_wait(); | |
4519 | ||
4520 | /* Wait until all the ramblocks' dirty bitmap synced */ | |
4521 | while (ramblock_count--) { | |
4522 | qemu_sem_wait(&s->rp_state.rp_sem); | |
4523 | } | |
4524 | ||
4525 | trace_ram_dirty_bitmap_sync_complete(); | |
4526 | ||
4527 | return 0; | |
4528 | } | |
4529 | ||
4530 | static void ram_dirty_bitmap_reload_notify(MigrationState *s) | |
4531 | { | |
4532 | qemu_sem_post(&s->rp_state.rp_sem); | |
4533 | } | |
4534 | ||
a335debb PX |
4535 | /* |
4536 | * Read the received bitmap, revert it as the initial dirty bitmap. | |
4537 | * This is only used when the postcopy migration is paused but wants | |
4538 | * to resume from a middle point. | |
4539 | */ | |
4540 | int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block) | |
4541 | { | |
4542 | int ret = -EINVAL; | |
43044ac0 | 4543 | /* from_dst_file is always valid because we're within rp_thread */ |
a335debb PX |
4544 | QEMUFile *file = s->rp_state.from_dst_file; |
4545 | unsigned long *le_bitmap, nbits = block->used_length >> TARGET_PAGE_BITS; | |
a725ef9f | 4546 | uint64_t local_size = DIV_ROUND_UP(nbits, 8); |
a335debb PX |
4547 | uint64_t size, end_mark; |
4548 | ||
4549 | trace_ram_dirty_bitmap_reload_begin(block->idstr); | |
4550 | ||
4551 | if (s->state != MIGRATION_STATUS_POSTCOPY_RECOVER) { | |
4552 | error_report("%s: incorrect state %s", __func__, | |
4553 | MigrationStatus_str(s->state)); | |
4554 | return -EINVAL; | |
4555 | } | |
4556 | ||
4557 | /* | |
4558 | * Note: see comments in ramblock_recv_bitmap_send() on why we | |
3a4452d8 | 4559 | * need the endianness conversion, and the paddings. |
a335debb PX |
4560 | */ |
4561 | local_size = ROUND_UP(local_size, 8); | |
4562 | ||
4563 | /* Add paddings */ | |
4564 | le_bitmap = bitmap_new(nbits + BITS_PER_LONG); | |
4565 | ||
4566 | size = qemu_get_be64(file); | |
4567 | ||
4568 | /* The size of the bitmap should match with our ramblock */ | |
4569 | if (size != local_size) { | |
4570 | error_report("%s: ramblock '%s' bitmap size mismatch " | |
4571 | "(0x%"PRIx64" != 0x%"PRIx64")", __func__, | |
4572 | block->idstr, size, local_size); | |
4573 | ret = -EINVAL; | |
4574 | goto out; | |
4575 | } | |
4576 | ||
4577 | size = qemu_get_buffer(file, (uint8_t *)le_bitmap, local_size); | |
4578 | end_mark = qemu_get_be64(file); | |
4579 | ||
4580 | ret = qemu_file_get_error(file); | |
4581 | if (ret || size != local_size) { | |
4582 | error_report("%s: read bitmap failed for ramblock '%s': %d" | |
4583 | " (size 0x%"PRIx64", got: 0x%"PRIx64")", | |
4584 | __func__, block->idstr, ret, local_size, size); | |
4585 | ret = -EIO; | |
4586 | goto out; | |
4587 | } | |
4588 | ||
4589 | if (end_mark != RAMBLOCK_RECV_BITMAP_ENDING) { | |
af3bbbe9 | 4590 | error_report("%s: ramblock '%s' end mark incorrect: 0x%"PRIx64, |
a335debb PX |
4591 | __func__, block->idstr, end_mark); |
4592 | ret = -EINVAL; | |
4593 | goto out; | |
4594 | } | |
4595 | ||
4596 | /* | |
3a4452d8 | 4597 | * Endianness conversion. We are during postcopy (though paused). |
a335debb PX |
4598 | * The dirty bitmap won't change. We can directly modify it. |
4599 | */ | |
4600 | bitmap_from_le(block->bmap, le_bitmap, nbits); | |
4601 | ||
4602 | /* | |
4603 | * What we received is "received bitmap". Revert it as the initial | |
4604 | * dirty bitmap for this ramblock. | |
4605 | */ | |
4606 | bitmap_complement(block->bmap, block->bmap, nbits); | |
4607 | ||
be39b4cd DH |
4608 | /* Clear dirty bits of discarded ranges that we don't want to migrate. */ |
4609 | ramblock_dirty_bitmap_clear_discarded_pages(block); | |
4610 | ||
4611 | /* We'll recalculate migration_dirty_pages in ram_state_resume_prepare(). */ | |
a335debb PX |
4612 | trace_ram_dirty_bitmap_reload_complete(block->idstr); |
4613 | ||
edd090c7 PX |
4614 | /* |
4615 | * We succeeded to sync bitmap for current ramblock. If this is | |
4616 | * the last one to sync, we need to notify the main send thread. | |
4617 | */ | |
4618 | ram_dirty_bitmap_reload_notify(s); | |
4619 | ||
a335debb PX |
4620 | ret = 0; |
4621 | out: | |
bf269906 | 4622 | g_free(le_bitmap); |
a335debb PX |
4623 | return ret; |
4624 | } | |
4625 | ||
edd090c7 PX |
4626 | static int ram_resume_prepare(MigrationState *s, void *opaque) |
4627 | { | |
4628 | RAMState *rs = *(RAMState **)opaque; | |
08614f34 | 4629 | int ret; |
edd090c7 | 4630 | |
08614f34 PX |
4631 | ret = ram_dirty_bitmap_sync_all(s, rs); |
4632 | if (ret) { | |
4633 | return ret; | |
4634 | } | |
4635 | ||
4636 | ram_state_resume_prepare(rs, s->to_dst_file); | |
4637 | ||
4638 | return 0; | |
edd090c7 PX |
4639 | } |
4640 | ||
36f62f11 PX |
4641 | void postcopy_preempt_shutdown_file(MigrationState *s) |
4642 | { | |
4643 | qemu_put_be64(s->postcopy_qemufile_src, RAM_SAVE_FLAG_EOS); | |
4644 | qemu_fflush(s->postcopy_qemufile_src); | |
4645 | } | |
4646 | ||
56e93d26 | 4647 | static SaveVMHandlers savevm_ram_handlers = { |
9907e842 | 4648 | .save_setup = ram_save_setup, |
56e93d26 | 4649 | .save_live_iterate = ram_save_iterate, |
763c906b | 4650 | .save_live_complete_postcopy = ram_save_complete, |
a3e06c3d | 4651 | .save_live_complete_precopy = ram_save_complete, |
c6467627 | 4652 | .has_postcopy = ram_has_postcopy, |
c8df4a7a JQ |
4653 | .state_pending_exact = ram_state_pending_exact, |
4654 | .state_pending_estimate = ram_state_pending_estimate, | |
56e93d26 | 4655 | .load_state = ram_load, |
f265e0e4 JQ |
4656 | .save_cleanup = ram_save_cleanup, |
4657 | .load_setup = ram_load_setup, | |
4658 | .load_cleanup = ram_load_cleanup, | |
edd090c7 | 4659 | .resume_prepare = ram_resume_prepare, |
56e93d26 JQ |
4660 | }; |
4661 | ||
c7c0e724 DH |
4662 | static void ram_mig_ram_block_resized(RAMBlockNotifier *n, void *host, |
4663 | size_t old_size, size_t new_size) | |
4664 | { | |
cc61c703 | 4665 | PostcopyState ps = postcopy_state_get(); |
c7c0e724 DH |
4666 | ram_addr_t offset; |
4667 | RAMBlock *rb = qemu_ram_block_from_host(host, false, &offset); | |
4668 | Error *err = NULL; | |
4669 | ||
4670 | if (ramblock_is_ignored(rb)) { | |
4671 | return; | |
4672 | } | |
4673 | ||
4674 | if (!migration_is_idle()) { | |
4675 | /* | |
4676 | * Precopy code on the source cannot deal with the size of RAM blocks | |
4677 | * changing at random points in time - especially after sending the | |
4678 | * RAM block sizes in the migration stream, they must no longer change. | |
4679 | * Abort and indicate a proper reason. | |
4680 | */ | |
4681 | error_setg(&err, "RAM block '%s' resized during precopy.", rb->idstr); | |
458fecca | 4682 | migration_cancel(err); |
c7c0e724 | 4683 | error_free(err); |
c7c0e724 | 4684 | } |
cc61c703 DH |
4685 | |
4686 | switch (ps) { | |
4687 | case POSTCOPY_INCOMING_ADVISE: | |
4688 | /* | |
4689 | * Update what ram_postcopy_incoming_init()->init_range() does at the | |
4690 | * time postcopy was advised. Syncing RAM blocks with the source will | |
4691 | * result in RAM resizes. | |
4692 | */ | |
4693 | if (old_size < new_size) { | |
4694 | if (ram_discard_range(rb->idstr, old_size, new_size - old_size)) { | |
4695 | error_report("RAM block '%s' discard of resized RAM failed", | |
4696 | rb->idstr); | |
4697 | } | |
4698 | } | |
898ba906 | 4699 | rb->postcopy_length = new_size; |
cc61c703 DH |
4700 | break; |
4701 | case POSTCOPY_INCOMING_NONE: | |
4702 | case POSTCOPY_INCOMING_RUNNING: | |
4703 | case POSTCOPY_INCOMING_END: | |
4704 | /* | |
4705 | * Once our guest is running, postcopy does no longer care about | |
4706 | * resizes. When growing, the new memory was not available on the | |
4707 | * source, no handler needed. | |
4708 | */ | |
4709 | break; | |
4710 | default: | |
4711 | error_report("RAM block '%s' resized during postcopy state: %d", | |
4712 | rb->idstr, ps); | |
4713 | exit(-1); | |
4714 | } | |
c7c0e724 DH |
4715 | } |
4716 | ||
4717 | static RAMBlockNotifier ram_mig_ram_notifier = { | |
4718 | .ram_block_resized = ram_mig_ram_block_resized, | |
4719 | }; | |
4720 | ||
56e93d26 JQ |
4721 | void ram_mig_init(void) |
4722 | { | |
4723 | qemu_mutex_init(&XBZRLE.lock); | |
ce62df53 | 4724 | register_savevm_live("ram", 0, 4, &savevm_ram_handlers, &ram_state); |
c7c0e724 | 4725 | ram_block_notifier_add(&ram_mig_ram_notifier); |
56e93d26 | 4726 | } |