xref: /openbmc/qemu/block/accounting.c (revision d38ea87a)
1 /*
2  * QEMU System Emulator block accounting
3  *
4  * Copyright (c) 2011 Christoph Hellwig
5  * Copyright (c) 2015 Igalia, S.L.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "block/accounting.h"
28 #include "block/block_int.h"
29 #include "qemu/timer.h"
30 #include "sysemu/qtest.h"
31 
32 static QEMUClockType clock_type = QEMU_CLOCK_REALTIME;
33 static const int qtest_latency_ns = NANOSECONDS_PER_SECOND / 1000;
34 
35 void block_acct_init(BlockAcctStats *stats, bool account_invalid,
36                      bool account_failed)
37 {
38     stats->account_invalid = account_invalid;
39     stats->account_failed = account_failed;
40 
41     if (qtest_enabled()) {
42         clock_type = QEMU_CLOCK_VIRTUAL;
43     }
44 }
45 
46 void block_acct_cleanup(BlockAcctStats *stats)
47 {
48     BlockAcctTimedStats *s, *next;
49     QSLIST_FOREACH_SAFE(s, &stats->intervals, entries, next) {
50         g_free(s);
51     }
52 }
53 
54 void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length)
55 {
56     BlockAcctTimedStats *s;
57     unsigned i;
58 
59     s = g_new0(BlockAcctTimedStats, 1);
60     s->interval_length = interval_length;
61     QSLIST_INSERT_HEAD(&stats->intervals, s, entries);
62 
63     for (i = 0; i < BLOCK_MAX_IOTYPE; i++) {
64         timed_average_init(&s->latency[i], clock_type,
65                            (uint64_t) interval_length * NANOSECONDS_PER_SECOND);
66     }
67 }
68 
69 BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats,
70                                               BlockAcctTimedStats *s)
71 {
72     if (s == NULL) {
73         return QSLIST_FIRST(&stats->intervals);
74     } else {
75         return QSLIST_NEXT(s, entries);
76     }
77 }
78 
79 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
80                       int64_t bytes, enum BlockAcctType type)
81 {
82     assert(type < BLOCK_MAX_IOTYPE);
83 
84     cookie->bytes = bytes;
85     cookie->start_time_ns = qemu_clock_get_ns(clock_type);
86     cookie->type = type;
87 }
88 
89 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
90 {
91     BlockAcctTimedStats *s;
92     int64_t time_ns = qemu_clock_get_ns(clock_type);
93     int64_t latency_ns = time_ns - cookie->start_time_ns;
94 
95     if (qtest_enabled()) {
96         latency_ns = qtest_latency_ns;
97     }
98 
99     assert(cookie->type < BLOCK_MAX_IOTYPE);
100 
101     stats->nr_bytes[cookie->type] += cookie->bytes;
102     stats->nr_ops[cookie->type]++;
103     stats->total_time_ns[cookie->type] += latency_ns;
104     stats->last_access_time_ns = time_ns;
105 
106     QSLIST_FOREACH(s, &stats->intervals, entries) {
107         timed_average_account(&s->latency[cookie->type], latency_ns);
108     }
109 }
110 
111 void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie)
112 {
113     assert(cookie->type < BLOCK_MAX_IOTYPE);
114 
115     stats->failed_ops[cookie->type]++;
116 
117     if (stats->account_failed) {
118         BlockAcctTimedStats *s;
119         int64_t time_ns = qemu_clock_get_ns(clock_type);
120         int64_t latency_ns = time_ns - cookie->start_time_ns;
121 
122         if (qtest_enabled()) {
123             latency_ns = qtest_latency_ns;
124         }
125 
126         stats->total_time_ns[cookie->type] += latency_ns;
127         stats->last_access_time_ns = time_ns;
128 
129         QSLIST_FOREACH(s, &stats->intervals, entries) {
130             timed_average_account(&s->latency[cookie->type], latency_ns);
131         }
132     }
133 }
134 
135 void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type)
136 {
137     assert(type < BLOCK_MAX_IOTYPE);
138 
139     /* block_acct_done() and block_acct_failed() update
140      * total_time_ns[], but this one does not. The reason is that
141      * invalid requests are accounted during their submission,
142      * therefore there's no actual I/O involved. */
143 
144     stats->invalid_ops[type]++;
145 
146     if (stats->account_invalid) {
147         stats->last_access_time_ns = qemu_clock_get_ns(clock_type);
148     }
149 }
150 
151 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
152                       int num_requests)
153 {
154     assert(type < BLOCK_MAX_IOTYPE);
155     stats->merged[type] += num_requests;
156 }
157 
158 int64_t block_acct_idle_time_ns(BlockAcctStats *stats)
159 {
160     return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns;
161 }
162 
163 double block_acct_queue_depth(BlockAcctTimedStats *stats,
164                               enum BlockAcctType type)
165 {
166     uint64_t sum, elapsed;
167 
168     assert(type < BLOCK_MAX_IOTYPE);
169 
170     sum = timed_average_sum(&stats->latency[type], &elapsed);
171 
172     return (double) sum / elapsed;
173 }
174