xref: /openbmc/qemu/block/accounting.c (revision dc5bd18f)
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)
36 {
37     qemu_mutex_init(&stats->lock);
38     if (qtest_enabled()) {
39         clock_type = QEMU_CLOCK_VIRTUAL;
40     }
41 }
42 
43 void block_acct_setup(BlockAcctStats *stats, bool account_invalid,
44                       bool account_failed)
45 {
46     stats->account_invalid = account_invalid;
47     stats->account_failed = account_failed;
48 }
49 
50 void block_acct_cleanup(BlockAcctStats *stats)
51 {
52     BlockAcctTimedStats *s, *next;
53     QSLIST_FOREACH_SAFE(s, &stats->intervals, entries, next) {
54         g_free(s);
55     }
56     qemu_mutex_destroy(&stats->lock);
57 }
58 
59 void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length)
60 {
61     BlockAcctTimedStats *s;
62     unsigned i;
63 
64     s = g_new0(BlockAcctTimedStats, 1);
65     s->interval_length = interval_length;
66     s->stats = stats;
67     qemu_mutex_lock(&stats->lock);
68     QSLIST_INSERT_HEAD(&stats->intervals, s, entries);
69 
70     for (i = 0; i < BLOCK_MAX_IOTYPE; i++) {
71         timed_average_init(&s->latency[i], clock_type,
72                            (uint64_t) interval_length * NANOSECONDS_PER_SECOND);
73     }
74     qemu_mutex_unlock(&stats->lock);
75 }
76 
77 BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats,
78                                               BlockAcctTimedStats *s)
79 {
80     if (s == NULL) {
81         return QSLIST_FIRST(&stats->intervals);
82     } else {
83         return QSLIST_NEXT(s, entries);
84     }
85 }
86 
87 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
88                       int64_t bytes, enum BlockAcctType type)
89 {
90     assert(type < BLOCK_MAX_IOTYPE);
91 
92     cookie->bytes = bytes;
93     cookie->start_time_ns = qemu_clock_get_ns(clock_type);
94     cookie->type = type;
95 }
96 
97 static void block_account_one_io(BlockAcctStats *stats, BlockAcctCookie *cookie,
98                                  bool failed)
99 {
100     BlockAcctTimedStats *s;
101     int64_t time_ns = qemu_clock_get_ns(clock_type);
102     int64_t latency_ns = time_ns - cookie->start_time_ns;
103 
104     if (qtest_enabled()) {
105         latency_ns = qtest_latency_ns;
106     }
107 
108     assert(cookie->type < BLOCK_MAX_IOTYPE);
109 
110     qemu_mutex_lock(&stats->lock);
111 
112     if (failed) {
113         stats->failed_ops[cookie->type]++;
114     } else {
115         stats->nr_bytes[cookie->type] += cookie->bytes;
116         stats->nr_ops[cookie->type]++;
117     }
118 
119     if (!failed || stats->account_failed) {
120         stats->total_time_ns[cookie->type] += latency_ns;
121         stats->last_access_time_ns = time_ns;
122 
123         QSLIST_FOREACH(s, &stats->intervals, entries) {
124             timed_average_account(&s->latency[cookie->type], latency_ns);
125         }
126     }
127 
128     qemu_mutex_unlock(&stats->lock);
129 }
130 
131 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie)
132 {
133     block_account_one_io(stats, cookie, false);
134 }
135 
136 void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie)
137 {
138     block_account_one_io(stats, cookie, true);
139 }
140 
141 void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type)
142 {
143     assert(type < BLOCK_MAX_IOTYPE);
144 
145     /* block_account_one_io() updates total_time_ns[], but this one does
146      * not.  The reason is that invalid requests are accounted during their
147      * submission, therefore there's no actual I/O involved.
148      */
149     qemu_mutex_lock(&stats->lock);
150     stats->invalid_ops[type]++;
151 
152     if (stats->account_invalid) {
153         stats->last_access_time_ns = qemu_clock_get_ns(clock_type);
154     }
155     qemu_mutex_unlock(&stats->lock);
156 }
157 
158 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
159                       int num_requests)
160 {
161     assert(type < BLOCK_MAX_IOTYPE);
162 
163     qemu_mutex_lock(&stats->lock);
164     stats->merged[type] += num_requests;
165     qemu_mutex_unlock(&stats->lock);
166 }
167 
168 int64_t block_acct_idle_time_ns(BlockAcctStats *stats)
169 {
170     return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns;
171 }
172 
173 double block_acct_queue_depth(BlockAcctTimedStats *stats,
174                               enum BlockAcctType type)
175 {
176     uint64_t sum, elapsed;
177 
178     assert(type < BLOCK_MAX_IOTYPE);
179 
180     qemu_mutex_lock(&stats->stats->lock);
181     sum = timed_average_sum(&stats->latency[type], &elapsed);
182     qemu_mutex_unlock(&stats->stats->lock);
183 
184     return (double) sum / elapsed;
185 }
186