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 | /* block_latency_histogram_compare_func: |
98 | * Compare @key with interval [@it[0], @it[1]). |
99 | * Return: -1 if @key < @it[0] |
100 | * 0 if @key in [@it[0], @it[1]) |
101 | * +1 if @key >= @it[1] |
102 | */ |
103 | static int block_latency_histogram_compare_func(const void *key, const void *it) |
104 | { |
105 | uint64_t k = *(uint64_t *)key; |
106 | uint64_t a = ((uint64_t *)it)[0]; |
107 | uint64_t b = ((uint64_t *)it)[1]; |
108 | |
109 | return k < a ? -1 : (k < b ? 0 : 1); |
110 | } |
111 | |
112 | static void block_latency_histogram_account(BlockLatencyHistogram *hist, |
113 | int64_t latency_ns) |
114 | { |
115 | uint64_t *pos; |
116 | |
117 | if (hist->bins == NULL) { |
118 | /* histogram disabled */ |
119 | return; |
120 | } |
121 | |
122 | |
123 | if (latency_ns < hist->boundaries[0]) { |
124 | hist->bins[0]++; |
125 | return; |
126 | } |
127 | |
128 | if (latency_ns >= hist->boundaries[hist->nbins - 2]) { |
129 | hist->bins[hist->nbins - 1]++; |
130 | return; |
131 | } |
132 | |
133 | pos = bsearch(&latency_ns, hist->boundaries, hist->nbins - 2, |
134 | sizeof(hist->boundaries[0]), |
135 | block_latency_histogram_compare_func); |
136 | assert(pos != NULL); |
137 | |
138 | hist->bins[pos - hist->boundaries + 1]++; |
139 | } |
140 | |
141 | int block_latency_histogram_set(BlockAcctStats *stats, enum BlockAcctType type, |
142 | uint64List *boundaries) |
143 | { |
144 | BlockLatencyHistogram *hist = &stats->latency_histogram[type]; |
145 | uint64List *entry; |
146 | uint64_t *ptr; |
147 | uint64_t prev = 0; |
148 | int new_nbins = 1; |
149 | |
150 | for (entry = boundaries; entry; entry = entry->next) { |
151 | if (entry->value <= prev) { |
152 | return -EINVAL; |
153 | } |
154 | new_nbins++; |
155 | prev = entry->value; |
156 | } |
157 | |
158 | hist->nbins = new_nbins; |
159 | g_free(hist->boundaries); |
160 | hist->boundaries = g_new(uint64_t, hist->nbins - 1); |
161 | for (entry = boundaries, ptr = hist->boundaries; entry; |
162 | entry = entry->next, ptr++) |
163 | { |
164 | *ptr = entry->value; |
165 | } |
166 | |
167 | g_free(hist->bins); |
168 | hist->bins = g_new0(uint64_t, hist->nbins); |
169 | |
170 | return 0; |
171 | } |
172 | |
173 | void block_latency_histograms_clear(BlockAcctStats *stats) |
174 | { |
175 | int i; |
176 | |
177 | for (i = 0; i < BLOCK_MAX_IOTYPE; i++) { |
178 | BlockLatencyHistogram *hist = &stats->latency_histogram[i]; |
179 | g_free(hist->bins); |
180 | g_free(hist->boundaries); |
181 | memset(hist, 0, sizeof(*hist)); |
182 | } |
183 | } |
184 | |
185 | static void block_account_one_io(BlockAcctStats *stats, BlockAcctCookie *cookie, |
186 | bool failed) |
187 | { |
188 | BlockAcctTimedStats *s; |
189 | int64_t time_ns = qemu_clock_get_ns(clock_type); |
190 | int64_t latency_ns = time_ns - cookie->start_time_ns; |
191 | |
192 | if (qtest_enabled()) { |
193 | latency_ns = qtest_latency_ns; |
194 | } |
195 | |
196 | assert(cookie->type < BLOCK_MAX_IOTYPE); |
197 | |
198 | qemu_mutex_lock(&stats->lock); |
199 | |
200 | if (failed) { |
201 | stats->failed_ops[cookie->type]++; |
202 | } else { |
203 | stats->nr_bytes[cookie->type] += cookie->bytes; |
204 | stats->nr_ops[cookie->type]++; |
205 | } |
206 | |
207 | block_latency_histogram_account(&stats->latency_histogram[cookie->type], |
208 | latency_ns); |
209 | |
210 | if (!failed || stats->account_failed) { |
211 | stats->total_time_ns[cookie->type] += latency_ns; |
212 | stats->last_access_time_ns = time_ns; |
213 | |
214 | QSLIST_FOREACH(s, &stats->intervals, entries) { |
215 | timed_average_account(&s->latency[cookie->type], latency_ns); |
216 | } |
217 | } |
218 | |
219 | qemu_mutex_unlock(&stats->lock); |
220 | } |
221 | |
222 | void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie) |
223 | { |
224 | block_account_one_io(stats, cookie, false); |
225 | } |
226 | |
227 | void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie) |
228 | { |
229 | block_account_one_io(stats, cookie, true); |
230 | } |
231 | |
232 | void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type) |
233 | { |
234 | assert(type < BLOCK_MAX_IOTYPE); |
235 | |
236 | /* block_account_one_io() updates total_time_ns[], but this one does |
237 | * not. The reason is that invalid requests are accounted during their |
238 | * submission, therefore there's no actual I/O involved. |
239 | */ |
240 | qemu_mutex_lock(&stats->lock); |
241 | stats->invalid_ops[type]++; |
242 | |
243 | if (stats->account_invalid) { |
244 | stats->last_access_time_ns = qemu_clock_get_ns(clock_type); |
245 | } |
246 | qemu_mutex_unlock(&stats->lock); |
247 | } |
248 | |
249 | void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type, |
250 | int num_requests) |
251 | { |
252 | assert(type < BLOCK_MAX_IOTYPE); |
253 | |
254 | qemu_mutex_lock(&stats->lock); |
255 | stats->merged[type] += num_requests; |
256 | qemu_mutex_unlock(&stats->lock); |
257 | } |
258 | |
259 | int64_t block_acct_idle_time_ns(BlockAcctStats *stats) |
260 | { |
261 | return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns; |
262 | } |
263 | |
264 | double block_acct_queue_depth(BlockAcctTimedStats *stats, |
265 | enum BlockAcctType type) |
266 | { |
267 | uint64_t sum, elapsed; |
268 | |
269 | assert(type < BLOCK_MAX_IOTYPE); |
270 | |
271 | qemu_mutex_lock(&stats->stats->lock); |
272 | sum = timed_average_sum(&stats->latency[type], &elapsed); |
273 | qemu_mutex_unlock(&stats->stats->lock); |
274 | |
275 | return (double) sum / elapsed; |
276 | } |
277 | |