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13#include "qemu/osdep.h"
14#include <zlib.h>
15#include "qapi/error.h"
16#include "cpu.h"
17#include "exec/ramblock.h"
18#include "qemu/rcu_queue.h"
19#include "qapi/qapi-commands-migration.h"
20#include "ram.h"
21#include "trace.h"
22#include "dirtyrate.h"
23#include "monitor/hmp.h"
24#include "monitor/monitor.h"
25#include "qapi/qmp/qdict.h"
26
27static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
28static struct DirtyRateStat DirtyStat;
29
30static int64_t set_sample_page_period(int64_t msec, int64_t initial_time)
31{
32 int64_t current_time;
33
34 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
35 if ((current_time - initial_time) >= msec) {
36 msec = current_time - initial_time;
37 } else {
38 g_usleep((msec + initial_time - current_time) * 1000);
39 }
40
41 return msec;
42}
43
44static bool is_sample_period_valid(int64_t sec)
45{
46 if (sec < MIN_FETCH_DIRTYRATE_TIME_SEC ||
47 sec > MAX_FETCH_DIRTYRATE_TIME_SEC) {
48 return false;
49 }
50
51 return true;
52}
53
54static bool is_sample_pages_valid(int64_t pages)
55{
56 return pages >= MIN_SAMPLE_PAGE_COUNT &&
57 pages <= MAX_SAMPLE_PAGE_COUNT;
58}
59
60static int dirtyrate_set_state(int *state, int old_state, int new_state)
61{
62 assert(new_state < DIRTY_RATE_STATUS__MAX);
63 trace_dirtyrate_set_state(DirtyRateStatus_str(new_state));
64 if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
65 return 0;
66 } else {
67 return -1;
68 }
69}
70
71static struct DirtyRateInfo *query_dirty_rate_info(void)
72{
73 int64_t dirty_rate = DirtyStat.dirty_rate;
74 struct DirtyRateInfo *info = g_malloc0(sizeof(DirtyRateInfo));
75
76 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURED) {
77 info->has_dirty_rate = true;
78 info->dirty_rate = dirty_rate;
79 }
80
81 info->status = CalculatingState;
82 info->start_time = DirtyStat.start_time;
83 info->calc_time = DirtyStat.calc_time;
84 info->sample_pages = DirtyStat.sample_pages;
85
86 trace_query_dirty_rate_info(DirtyRateStatus_str(CalculatingState));
87
88 return info;
89}
90
91static void init_dirtyrate_stat(int64_t start_time, int64_t calc_time,
92 uint64_t sample_pages)
93{
94 DirtyStat.total_dirty_samples = 0;
95 DirtyStat.total_sample_count = 0;
96 DirtyStat.total_block_mem_MB = 0;
97 DirtyStat.dirty_rate = -1;
98 DirtyStat.start_time = start_time;
99 DirtyStat.calc_time = calc_time;
100 DirtyStat.sample_pages = sample_pages;
101}
102
103static void update_dirtyrate_stat(struct RamblockDirtyInfo *info)
104{
105 DirtyStat.total_dirty_samples += info->sample_dirty_count;
106 DirtyStat.total_sample_count += info->sample_pages_count;
107
108 DirtyStat.total_block_mem_MB += (info->ramblock_pages *
109 TARGET_PAGE_SIZE) >> 20;
110}
111
112static void update_dirtyrate(uint64_t msec)
113{
114 uint64_t dirtyrate;
115 uint64_t total_dirty_samples = DirtyStat.total_dirty_samples;
116 uint64_t total_sample_count = DirtyStat.total_sample_count;
117 uint64_t total_block_mem_MB = DirtyStat.total_block_mem_MB;
118
119 dirtyrate = total_dirty_samples * total_block_mem_MB *
120 1000 / (total_sample_count * msec);
121
122 DirtyStat.dirty_rate = dirtyrate;
123}
124
125
126
127
128
129static uint32_t get_ramblock_vfn_hash(struct RamblockDirtyInfo *info,
130 uint64_t vfn)
131{
132 uint32_t crc;
133
134 crc = crc32(0, (info->ramblock_addr +
135 vfn * TARGET_PAGE_SIZE), TARGET_PAGE_SIZE);
136
137 trace_get_ramblock_vfn_hash(info->idstr, vfn, crc);
138 return crc;
139}
140
141static bool save_ramblock_hash(struct RamblockDirtyInfo *info)
142{
143 unsigned int sample_pages_count;
144 int i;
145 GRand *rand;
146
147 sample_pages_count = info->sample_pages_count;
148
149
150 if (unlikely(info->ramblock_pages == 0 || sample_pages_count == 0)) {
151 return true;
152 }
153
154 info->hash_result = g_try_malloc0_n(sample_pages_count,
155 sizeof(uint32_t));
156 if (!info->hash_result) {
157 return false;
158 }
159
160 info->sample_page_vfn = g_try_malloc0_n(sample_pages_count,
161 sizeof(uint64_t));
162 if (!info->sample_page_vfn) {
163 g_free(info->hash_result);
164 return false;
165 }
166
167 rand = g_rand_new();
168 for (i = 0; i < sample_pages_count; i++) {
169 info->sample_page_vfn[i] = g_rand_int_range(rand, 0,
170 info->ramblock_pages - 1);
171 info->hash_result[i] = get_ramblock_vfn_hash(info,
172 info->sample_page_vfn[i]);
173 }
174 g_rand_free(rand);
175
176 return true;
177}
178
179static void get_ramblock_dirty_info(RAMBlock *block,
180 struct RamblockDirtyInfo *info,
181 struct DirtyRateConfig *config)
182{
183 uint64_t sample_pages_per_gigabytes = config->sample_pages_per_gigabytes;
184
185
186 info->sample_pages_count = (qemu_ram_get_used_length(block) *
187 sample_pages_per_gigabytes) >> 30;
188
189 info->ramblock_pages = qemu_ram_get_used_length(block) >>
190 TARGET_PAGE_BITS;
191 info->ramblock_addr = qemu_ram_get_host_addr(block);
192 strcpy(info->idstr, qemu_ram_get_idstr(block));
193}
194
195static void free_ramblock_dirty_info(struct RamblockDirtyInfo *infos, int count)
196{
197 int i;
198
199 if (!infos) {
200 return;
201 }
202
203 for (i = 0; i < count; i++) {
204 g_free(infos[i].sample_page_vfn);
205 g_free(infos[i].hash_result);
206 }
207 g_free(infos);
208}
209
210static bool skip_sample_ramblock(RAMBlock *block)
211{
212
213
214
215 if (qemu_ram_get_used_length(block) < (MIN_RAMBLOCK_SIZE << 10)) {
216 trace_skip_sample_ramblock(block->idstr,
217 qemu_ram_get_used_length(block));
218 return true;
219 }
220
221 return false;
222}
223
224static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo,
225 struct DirtyRateConfig config,
226 int *block_count)
227{
228 struct RamblockDirtyInfo *info = NULL;
229 struct RamblockDirtyInfo *dinfo = NULL;
230 RAMBlock *block = NULL;
231 int total_count = 0;
232 int index = 0;
233 bool ret = false;
234
235 RAMBLOCK_FOREACH_MIGRATABLE(block) {
236 if (skip_sample_ramblock(block)) {
237 continue;
238 }
239 total_count++;
240 }
241
242 dinfo = g_try_malloc0_n(total_count, sizeof(struct RamblockDirtyInfo));
243 if (dinfo == NULL) {
244 goto out;
245 }
246
247 RAMBLOCK_FOREACH_MIGRATABLE(block) {
248 if (skip_sample_ramblock(block)) {
249 continue;
250 }
251 if (index >= total_count) {
252 break;
253 }
254 info = &dinfo[index];
255 get_ramblock_dirty_info(block, info, &config);
256 if (!save_ramblock_hash(info)) {
257 goto out;
258 }
259 index++;
260 }
261 ret = true;
262
263out:
264 *block_count = index;
265 *block_dinfo = dinfo;
266 return ret;
267}
268
269static void calc_page_dirty_rate(struct RamblockDirtyInfo *info)
270{
271 uint32_t crc;
272 int i;
273
274 for (i = 0; i < info->sample_pages_count; i++) {
275 crc = get_ramblock_vfn_hash(info, info->sample_page_vfn[i]);
276 if (crc != info->hash_result[i]) {
277 trace_calc_page_dirty_rate(info->idstr, crc, info->hash_result[i]);
278 info->sample_dirty_count++;
279 }
280 }
281}
282
283static struct RamblockDirtyInfo *
284find_block_matched(RAMBlock *block, int count,
285 struct RamblockDirtyInfo *infos)
286{
287 int i;
288 struct RamblockDirtyInfo *matched;
289
290 for (i = 0; i < count; i++) {
291 if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) {
292 break;
293 }
294 }
295
296 if (i == count) {
297 return NULL;
298 }
299
300 if (infos[i].ramblock_addr != qemu_ram_get_host_addr(block) ||
301 infos[i].ramblock_pages !=
302 (qemu_ram_get_used_length(block) >> TARGET_PAGE_BITS)) {
303 trace_find_page_matched(block->idstr);
304 return NULL;
305 }
306
307 matched = &infos[i];
308
309 return matched;
310}
311
312static bool compare_page_hash_info(struct RamblockDirtyInfo *info,
313 int block_count)
314{
315 struct RamblockDirtyInfo *block_dinfo = NULL;
316 RAMBlock *block = NULL;
317
318 RAMBLOCK_FOREACH_MIGRATABLE(block) {
319 if (skip_sample_ramblock(block)) {
320 continue;
321 }
322 block_dinfo = find_block_matched(block, block_count, info);
323 if (block_dinfo == NULL) {
324 continue;
325 }
326 calc_page_dirty_rate(block_dinfo);
327 update_dirtyrate_stat(block_dinfo);
328 }
329
330 if (DirtyStat.total_sample_count == 0) {
331 return false;
332 }
333
334 return true;
335}
336
337static void calculate_dirtyrate(struct DirtyRateConfig config)
338{
339 struct RamblockDirtyInfo *block_dinfo = NULL;
340 int block_count = 0;
341 int64_t msec = 0;
342 int64_t initial_time;
343
344 rcu_register_thread();
345 rcu_read_lock();
346 initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
347 if (!record_ramblock_hash_info(&block_dinfo, config, &block_count)) {
348 goto out;
349 }
350 rcu_read_unlock();
351
352 msec = config.sample_period_seconds * 1000;
353 msec = set_sample_page_period(msec, initial_time);
354 DirtyStat.start_time = initial_time / 1000;
355 DirtyStat.calc_time = msec / 1000;
356
357 rcu_read_lock();
358 if (!compare_page_hash_info(block_dinfo, block_count)) {
359 goto out;
360 }
361
362 update_dirtyrate(msec);
363
364out:
365 rcu_read_unlock();
366 free_ramblock_dirty_info(block_dinfo, block_count);
367 rcu_unregister_thread();
368}
369
370void *get_dirtyrate_thread(void *arg)
371{
372 struct DirtyRateConfig config = *(struct DirtyRateConfig *)arg;
373 int ret;
374 int64_t start_time;
375 int64_t calc_time;
376 uint64_t sample_pages;
377
378 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_UNSTARTED,
379 DIRTY_RATE_STATUS_MEASURING);
380 if (ret == -1) {
381 error_report("change dirtyrate state failed.");
382 return NULL;
383 }
384
385 start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) / 1000;
386 calc_time = config.sample_period_seconds;
387 sample_pages = config.sample_pages_per_gigabytes;
388 init_dirtyrate_stat(start_time, calc_time, sample_pages);
389
390 calculate_dirtyrate(config);
391
392 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_MEASURING,
393 DIRTY_RATE_STATUS_MEASURED);
394 if (ret == -1) {
395 error_report("change dirtyrate state failed.");
396 }
397 return NULL;
398}
399
400void qmp_calc_dirty_rate(int64_t calc_time, bool has_sample_pages,
401 int64_t sample_pages, Error **errp)
402{
403 static struct DirtyRateConfig config;
404 QemuThread thread;
405 int ret;
406
407
408
409
410 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURING) {
411 error_setg(errp, "the dirty rate is already being measured.");
412 return;
413 }
414
415 if (!is_sample_period_valid(calc_time)) {
416 error_setg(errp, "calc-time is out of range[%d, %d].",
417 MIN_FETCH_DIRTYRATE_TIME_SEC,
418 MAX_FETCH_DIRTYRATE_TIME_SEC);
419 return;
420 }
421
422 if (has_sample_pages) {
423 if (!is_sample_pages_valid(sample_pages)) {
424 error_setg(errp, "sample-pages is out of range[%d, %d].",
425 MIN_SAMPLE_PAGE_COUNT,
426 MAX_SAMPLE_PAGE_COUNT);
427 return;
428 }
429 } else {
430 sample_pages = DIRTYRATE_DEFAULT_SAMPLE_PAGES;
431 }
432
433
434
435
436 ret = dirtyrate_set_state(&CalculatingState, CalculatingState,
437 DIRTY_RATE_STATUS_UNSTARTED);
438 if (ret == -1) {
439 error_setg(errp, "init dirty rate calculation state failed.");
440 return;
441 }
442
443 config.sample_period_seconds = calc_time;
444 config.sample_pages_per_gigabytes = sample_pages;
445 qemu_thread_create(&thread, "get_dirtyrate", get_dirtyrate_thread,
446 (void *)&config, QEMU_THREAD_DETACHED);
447}
448
449struct DirtyRateInfo *qmp_query_dirty_rate(Error **errp)
450{
451 return query_dirty_rate_info();
452}
453
454void hmp_info_dirty_rate(Monitor *mon, const QDict *qdict)
455{
456 DirtyRateInfo *info = query_dirty_rate_info();
457
458 monitor_printf(mon, "Status: %s\n",
459 DirtyRateStatus_str(info->status));
460 monitor_printf(mon, "Start Time: %"PRIi64" (ms)\n",
461 info->start_time);
462 monitor_printf(mon, "Sample Pages: %"PRIu64" (per GB)\n",
463 info->sample_pages);
464 monitor_printf(mon, "Period: %"PRIi64" (sec)\n",
465 info->calc_time);
466 monitor_printf(mon, "Dirty rate: ");
467 if (info->has_dirty_rate) {
468 monitor_printf(mon, "%"PRIi64" (MB/s)\n", info->dirty_rate);
469 } else {
470 monitor_printf(mon, "(not ready)\n");
471 }
472 g_free(info);
473}
474
475void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict)
476{
477 int64_t sec = qdict_get_try_int(qdict, "second", 0);
478 int64_t sample_pages = qdict_get_try_int(qdict, "sample_pages_per_GB", -1);
479 bool has_sample_pages = (sample_pages != -1);
480 Error *err = NULL;
481
482 if (!sec) {
483 monitor_printf(mon, "Incorrect period length specified!\n");
484 return;
485 }
486
487 qmp_calc_dirty_rate(sec, has_sample_pages, sample_pages, &err);
488 if (err) {
489 hmp_handle_error(mon, err);
490 return;
491 }
492
493 monitor_printf(mon, "Starting dirty rate measurement with period %"PRIi64
494 " seconds\n", sec);
495 monitor_printf(mon, "[Please use 'info dirty_rate' to check results]\n");
496}
497
