xref: /openbmc/qemu/migration/dirtyrate.h (revision b91a0fa7)
1 /*
2  *  Dirtyrate common functions
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 #ifndef QEMU_MIGRATION_DIRTYRATE_H
14 #define QEMU_MIGRATION_DIRTYRATE_H
15 
16 /*
17  * Sample 512 pages per GB as default.
18  */
19 #define DIRTYRATE_DEFAULT_SAMPLE_PAGES            512
20 
21 /*
22  * Record ramblock idstr
23  */
24 #define RAMBLOCK_INFO_MAX_LEN                     256
25 
26 /*
27  * Minimum RAMBlock size to sample, in megabytes.
28  */
29 #define MIN_RAMBLOCK_SIZE                         128
30 
31 /*
32  * Take 1s as minimum time for calculation duration
33  */
34 #define MIN_FETCH_DIRTYRATE_TIME_SEC              1
35 #define MAX_FETCH_DIRTYRATE_TIME_SEC              60
36 
37 /*
38  * Take 1/16 pages in 1G as the maxmum sample page count
39  */
40 #define MIN_SAMPLE_PAGE_COUNT                     128
41 #define MAX_SAMPLE_PAGE_COUNT                     16384
42 
43 struct DirtyRateConfig {
44     uint64_t sample_pages_per_gigabytes; /* sample pages per GB */
45     int64_t sample_period_seconds; /* time duration between two sampling */
46     DirtyRateMeasureMode mode; /* mode of dirtyrate measurement */
47 };
48 
49 /*
50  * Store dirtypage info for each ramblock.
51  */
52 struct RamblockDirtyInfo {
53     char idstr[RAMBLOCK_INFO_MAX_LEN]; /* idstr for each ramblock */
54     uint8_t *ramblock_addr; /* base address of ramblock we measure */
55     uint64_t ramblock_pages; /* ramblock size in TARGET_PAGE_SIZE */
56     uint64_t *sample_page_vfn; /* relative offset address for sampled page */
57     uint64_t sample_pages_count; /* count of sampled pages */
58     uint64_t sample_dirty_count; /* count of dirty pages we measure */
59     uint32_t *hash_result; /* array of hash result for sampled pages */
60 };
61 
62 typedef struct SampleVMStat {
63     uint64_t total_dirty_samples; /* total dirty sampled page */
64     uint64_t total_sample_count; /* total sampled pages */
65     uint64_t total_block_mem_MB; /* size of total sampled pages in MB */
66 } SampleVMStat;
67 
68 typedef struct VcpuStat {
69     int nvcpu; /* number of vcpu */
70     DirtyRateVcpu *rates; /* array of dirty rate for each vcpu */
71 } VcpuStat;
72 
73 /*
74  * Store calculation statistics for each measure.
75  */
76 struct DirtyRateStat {
77     int64_t dirty_rate; /* dirty rate in MB/s */
78     int64_t start_time; /* calculation start time in units of second */
79     int64_t calc_time; /* time duration of two sampling in units of second */
80     uint64_t sample_pages; /* sample pages per GB */
81     union {
82         SampleVMStat page_sampling;
83         VcpuStat dirty_ring;
84     };
85 };
86 
87 void *get_dirtyrate_thread(void *arg);
88 #endif
89