usb/hcd-xhci: Split pci wrapper for xhci base model
[qemu.git] / migration / dirtyrate.c
1 /*
2 * Dirtyrate implement code
3 *
4 * Copyright (c) 2020 HUAWEI TECHNOLOGIES CO.,LTD.
5 *
6 * Authors:
7 * Chuan Zheng <zhengchuan@huawei.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13 #include <zlib.h>
14 #include "qemu/osdep.h"
15 #include "qapi/error.h"
16 #include "cpu.h"
17 #include "qemu/config-file.h"
18 #include "exec/memory.h"
19 #include "exec/ramblock.h"
20 #include "exec/target_page.h"
21 #include "qemu/rcu_queue.h"
22 #include "qapi/qapi-commands-migration.h"
23 #include "migration.h"
24 #include "ram.h"
25 #include "trace.h"
26 #include "dirtyrate.h"
27
28 static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
29 static struct DirtyRateStat DirtyStat;
30
31 static int64_t set_sample_page_period(int64_t msec, int64_t initial_time)
32 {
33 int64_t current_time;
34
35 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
36 if ((current_time - initial_time) >= msec) {
37 msec = current_time - initial_time;
38 } else {
39 g_usleep((msec + initial_time - current_time) * 1000);
40 }
41
42 return msec;
43 }
44
45 static bool is_sample_period_valid(int64_t sec)
46 {
47 if (sec < MIN_FETCH_DIRTYRATE_TIME_SEC ||
48 sec > MAX_FETCH_DIRTYRATE_TIME_SEC) {
49 return false;
50 }
51
52 return true;
53 }
54
55 static int dirtyrate_set_state(int *state, int old_state, int new_state)
56 {
57 assert(new_state < DIRTY_RATE_STATUS__MAX);
58 trace_dirtyrate_set_state(DirtyRateStatus_str(new_state));
59 if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
60 return 0;
61 } else {
62 return -1;
63 }
64 }
65
66 static struct DirtyRateInfo *query_dirty_rate_info(void)
67 {
68 int64_t dirty_rate = DirtyStat.dirty_rate;
69 struct DirtyRateInfo *info = g_malloc0(sizeof(DirtyRateInfo));
70
71 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURED) {
72 info->dirty_rate = dirty_rate;
73 } else {
74 info->dirty_rate = -1;
75 }
76
77 info->status = CalculatingState;
78 info->start_time = DirtyStat.start_time;
79 info->calc_time = DirtyStat.calc_time;
80
81 trace_query_dirty_rate_info(DirtyRateStatus_str(CalculatingState));
82
83 return info;
84 }
85
86 static void reset_dirtyrate_stat(void)
87 {
88 DirtyStat.total_dirty_samples = 0;
89 DirtyStat.total_sample_count = 0;
90 DirtyStat.total_block_mem_MB = 0;
91 DirtyStat.dirty_rate = -1;
92 DirtyStat.start_time = 0;
93 DirtyStat.calc_time = 0;
94 }
95
96 static void update_dirtyrate_stat(struct RamblockDirtyInfo *info)
97 {
98 DirtyStat.total_dirty_samples += info->sample_dirty_count;
99 DirtyStat.total_sample_count += info->sample_pages_count;
100 /* size of total pages in MB */
101 DirtyStat.total_block_mem_MB += (info->ramblock_pages *
102 TARGET_PAGE_SIZE) >> 20;
103 }
104
105 static void update_dirtyrate(uint64_t msec)
106 {
107 uint64_t dirtyrate;
108 uint64_t total_dirty_samples = DirtyStat.total_dirty_samples;
109 uint64_t total_sample_count = DirtyStat.total_sample_count;
110 uint64_t total_block_mem_MB = DirtyStat.total_block_mem_MB;
111
112 dirtyrate = total_dirty_samples * total_block_mem_MB *
113 1000 / (total_sample_count * msec);
114
115 DirtyStat.dirty_rate = dirtyrate;
116 }
117
118 /*
119 * get hash result for the sampled memory with length of TARGET_PAGE_SIZE
120 * in ramblock, which starts from ramblock base address.
121 */
122 static uint32_t get_ramblock_vfn_hash(struct RamblockDirtyInfo *info,
123 uint64_t vfn)
124 {
125 uint32_t crc;
126
127 crc = crc32(0, (info->ramblock_addr +
128 vfn * TARGET_PAGE_SIZE), TARGET_PAGE_SIZE);
129
130 trace_get_ramblock_vfn_hash(info->idstr, vfn, crc);
131 return crc;
132 }
133
134 static bool save_ramblock_hash(struct RamblockDirtyInfo *info)
135 {
136 unsigned int sample_pages_count;
137 int i;
138 GRand *rand;
139
140 sample_pages_count = info->sample_pages_count;
141
142 /* ramblock size less than one page, return success to skip this ramblock */
143 if (unlikely(info->ramblock_pages == 0 || sample_pages_count == 0)) {
144 return true;
145 }
146
147 info->hash_result = g_try_malloc0_n(sample_pages_count,
148 sizeof(uint32_t));
149 if (!info->hash_result) {
150 return false;
151 }
152
153 info->sample_page_vfn = g_try_malloc0_n(sample_pages_count,
154 sizeof(uint64_t));
155 if (!info->sample_page_vfn) {
156 g_free(info->hash_result);
157 return false;
158 }
159
160 rand = g_rand_new();
161 for (i = 0; i < sample_pages_count; i++) {
162 info->sample_page_vfn[i] = g_rand_int_range(rand, 0,
163 info->ramblock_pages - 1);
164 info->hash_result[i] = get_ramblock_vfn_hash(info,
165 info->sample_page_vfn[i]);
166 }
167 g_rand_free(rand);
168
169 return true;
170 }
171
172 static void get_ramblock_dirty_info(RAMBlock *block,
173 struct RamblockDirtyInfo *info,
174 struct DirtyRateConfig *config)
175 {
176 uint64_t sample_pages_per_gigabytes = config->sample_pages_per_gigabytes;
177
178 /* Right shift 30 bits to calc ramblock size in GB */
179 info->sample_pages_count = (qemu_ram_get_used_length(block) *
180 sample_pages_per_gigabytes) >> 30;
181 /* Right shift TARGET_PAGE_BITS to calc page count */
182 info->ramblock_pages = qemu_ram_get_used_length(block) >>
183 TARGET_PAGE_BITS;
184 info->ramblock_addr = qemu_ram_get_host_addr(block);
185 strcpy(info->idstr, qemu_ram_get_idstr(block));
186 }
187
188 static void free_ramblock_dirty_info(struct RamblockDirtyInfo *infos, int count)
189 {
190 int i;
191
192 if (!infos) {
193 return;
194 }
195
196 for (i = 0; i < count; i++) {
197 g_free(infos[i].sample_page_vfn);
198 g_free(infos[i].hash_result);
199 }
200 g_free(infos);
201 }
202
203 static bool skip_sample_ramblock(RAMBlock *block)
204 {
205 /*
206 * Sample only blocks larger than MIN_RAMBLOCK_SIZE.
207 */
208 if (qemu_ram_get_used_length(block) < (MIN_RAMBLOCK_SIZE << 10)) {
209 trace_skip_sample_ramblock(block->idstr,
210 qemu_ram_get_used_length(block));
211 return true;
212 }
213
214 return false;
215 }
216
217 static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo,
218 struct DirtyRateConfig config,
219 int *block_count)
220 {
221 struct RamblockDirtyInfo *info = NULL;
222 struct RamblockDirtyInfo *dinfo = NULL;
223 RAMBlock *block = NULL;
224 int total_count = 0;
225 int index = 0;
226 bool ret = false;
227
228 RAMBLOCK_FOREACH_MIGRATABLE(block) {
229 if (skip_sample_ramblock(block)) {
230 continue;
231 }
232 total_count++;
233 }
234
235 dinfo = g_try_malloc0_n(total_count, sizeof(struct RamblockDirtyInfo));
236 if (dinfo == NULL) {
237 goto out;
238 }
239
240 RAMBLOCK_FOREACH_MIGRATABLE(block) {
241 if (skip_sample_ramblock(block)) {
242 continue;
243 }
244 if (index >= total_count) {
245 break;
246 }
247 info = &dinfo[index];
248 get_ramblock_dirty_info(block, info, &config);
249 if (!save_ramblock_hash(info)) {
250 goto out;
251 }
252 index++;
253 }
254 ret = true;
255
256 out:
257 *block_count = index;
258 *block_dinfo = dinfo;
259 return ret;
260 }
261
262 static void calc_page_dirty_rate(struct RamblockDirtyInfo *info)
263 {
264 uint32_t crc;
265 int i;
266
267 for (i = 0; i < info->sample_pages_count; i++) {
268 crc = get_ramblock_vfn_hash(info, info->sample_page_vfn[i]);
269 if (crc != info->hash_result[i]) {
270 trace_calc_page_dirty_rate(info->idstr, crc, info->hash_result[i]);
271 info->sample_dirty_count++;
272 }
273 }
274 }
275
276 static struct RamblockDirtyInfo *
277 find_block_matched(RAMBlock *block, int count,
278 struct RamblockDirtyInfo *infos)
279 {
280 int i;
281 struct RamblockDirtyInfo *matched;
282
283 for (i = 0; i < count; i++) {
284 if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) {
285 break;
286 }
287 }
288
289 if (i == count) {
290 return NULL;
291 }
292
293 if (infos[i].ramblock_addr != qemu_ram_get_host_addr(block) ||
294 infos[i].ramblock_pages !=
295 (qemu_ram_get_used_length(block) >> TARGET_PAGE_BITS)) {
296 trace_find_page_matched(block->idstr);
297 return NULL;
298 }
299
300 matched = &infos[i];
301
302 return matched;
303 }
304
305 static bool compare_page_hash_info(struct RamblockDirtyInfo *info,
306 int block_count)
307 {
308 struct RamblockDirtyInfo *block_dinfo = NULL;
309 RAMBlock *block = NULL;
310
311 RAMBLOCK_FOREACH_MIGRATABLE(block) {
312 if (skip_sample_ramblock(block)) {
313 continue;
314 }
315 block_dinfo = find_block_matched(block, block_count, info);
316 if (block_dinfo == NULL) {
317 continue;
318 }
319 calc_page_dirty_rate(block_dinfo);
320 update_dirtyrate_stat(block_dinfo);
321 }
322
323 if (DirtyStat.total_sample_count == 0) {
324 return false;
325 }
326
327 return true;
328 }
329
330 static void calculate_dirtyrate(struct DirtyRateConfig config)
331 {
332 struct RamblockDirtyInfo *block_dinfo = NULL;
333 int block_count = 0;
334 int64_t msec = 0;
335 int64_t initial_time;
336
337 rcu_register_thread();
338 reset_dirtyrate_stat();
339 rcu_read_lock();
340 initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
341 if (!record_ramblock_hash_info(&block_dinfo, config, &block_count)) {
342 goto out;
343 }
344 rcu_read_unlock();
345
346 msec = config.sample_period_seconds * 1000;
347 msec = set_sample_page_period(msec, initial_time);
348 DirtyStat.start_time = initial_time / 1000;
349 DirtyStat.calc_time = msec / 1000;
350
351 rcu_read_lock();
352 if (!compare_page_hash_info(block_dinfo, block_count)) {
353 goto out;
354 }
355
356 update_dirtyrate(msec);
357
358 out:
359 rcu_read_unlock();
360 free_ramblock_dirty_info(block_dinfo, block_count);
361 rcu_unregister_thread();
362 }
363
364 void *get_dirtyrate_thread(void *arg)
365 {
366 struct DirtyRateConfig config = *(struct DirtyRateConfig *)arg;
367 int ret;
368
369 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_UNSTARTED,
370 DIRTY_RATE_STATUS_MEASURING);
371 if (ret == -1) {
372 error_report("change dirtyrate state failed.");
373 return NULL;
374 }
375
376 calculate_dirtyrate(config);
377
378 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_MEASURING,
379 DIRTY_RATE_STATUS_MEASURED);
380 if (ret == -1) {
381 error_report("change dirtyrate state failed.");
382 }
383 return NULL;
384 }
385
386 void qmp_calc_dirty_rate(int64_t calc_time, Error **errp)
387 {
388 static struct DirtyRateConfig config;
389 QemuThread thread;
390 int ret;
391
392 /*
393 * If the dirty rate is already being measured, don't attempt to start.
394 */
395 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURING) {
396 error_setg(errp, "the dirty rate is already being measured.");
397 return;
398 }
399
400 if (!is_sample_period_valid(calc_time)) {
401 error_setg(errp, "calc-time is out of range[%d, %d].",
402 MIN_FETCH_DIRTYRATE_TIME_SEC,
403 MAX_FETCH_DIRTYRATE_TIME_SEC);
404 return;
405 }
406
407 /*
408 * Init calculation state as unstarted.
409 */
410 ret = dirtyrate_set_state(&CalculatingState, CalculatingState,
411 DIRTY_RATE_STATUS_UNSTARTED);
412 if (ret == -1) {
413 error_setg(errp, "init dirty rate calculation state failed.");
414 return;
415 }
416
417 config.sample_period_seconds = calc_time;
418 config.sample_pages_per_gigabytes = DIRTYRATE_DEFAULT_SAMPLE_PAGES;
419 qemu_thread_create(&thread, "get_dirtyrate", get_dirtyrate_thread,
420 (void *)&config, QEMU_THREAD_DETACHED);
421 }
422
423 struct DirtyRateInfo *qmp_query_dirty_rate(Error **errp)
424 {
425 return query_dirty_rate_info();
426 }