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 "block/accounting.h" 27 #include "block/block_int.h" 28 #include "qemu/timer.h" 29 #include "sysemu/qtest.h" 30 31 static QEMUClockType clock_type = QEMU_CLOCK_REALTIME; 32 static const int qtest_latency_ns = NANOSECONDS_PER_SECOND / 1000; 33 34 void block_acct_init(BlockAcctStats *stats, bool account_invalid, 35 bool account_failed) 36 { 37 stats->account_invalid = account_invalid; 38 stats->account_failed = account_failed; 39 40 if (qtest_enabled()) { 41 clock_type = QEMU_CLOCK_VIRTUAL; 42 } 43 } 44 45 void block_acct_cleanup(BlockAcctStats *stats) 46 { 47 BlockAcctTimedStats *s, *next; 48 QSLIST_FOREACH_SAFE(s, &stats->intervals, entries, next) { 49 g_free(s); 50 } 51 } 52 53 void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length) 54 { 55 BlockAcctTimedStats *s; 56 unsigned i; 57 58 s = g_new0(BlockAcctTimedStats, 1); 59 s->interval_length = interval_length; 60 QSLIST_INSERT_HEAD(&stats->intervals, s, entries); 61 62 for (i = 0; i < BLOCK_MAX_IOTYPE; i++) { 63 timed_average_init(&s->latency[i], clock_type, 64 (uint64_t) interval_length * NANOSECONDS_PER_SECOND); 65 } 66 } 67 68 BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats, 69 BlockAcctTimedStats *s) 70 { 71 if (s == NULL) { 72 return QSLIST_FIRST(&stats->intervals); 73 } else { 74 return QSLIST_NEXT(s, entries); 75 } 76 } 77 78 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie, 79 int64_t bytes, enum BlockAcctType type) 80 { 81 assert(type < BLOCK_MAX_IOTYPE); 82 83 cookie->bytes = bytes; 84 cookie->start_time_ns = qemu_clock_get_ns(clock_type); 85 cookie->type = type; 86 } 87 88 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie) 89 { 90 BlockAcctTimedStats *s; 91 int64_t time_ns = qemu_clock_get_ns(clock_type); 92 int64_t latency_ns = time_ns - cookie->start_time_ns; 93 94 if (qtest_enabled()) { 95 latency_ns = qtest_latency_ns; 96 } 97 98 assert(cookie->type < BLOCK_MAX_IOTYPE); 99 100 stats->nr_bytes[cookie->type] += cookie->bytes; 101 stats->nr_ops[cookie->type]++; 102 stats->total_time_ns[cookie->type] += latency_ns; 103 stats->last_access_time_ns = time_ns; 104 105 QSLIST_FOREACH(s, &stats->intervals, entries) { 106 timed_average_account(&s->latency[cookie->type], latency_ns); 107 } 108 } 109 110 void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie) 111 { 112 assert(cookie->type < BLOCK_MAX_IOTYPE); 113 114 stats->failed_ops[cookie->type]++; 115 116 if (stats->account_failed) { 117 BlockAcctTimedStats *s; 118 int64_t time_ns = qemu_clock_get_ns(clock_type); 119 int64_t latency_ns = time_ns - cookie->start_time_ns; 120 121 if (qtest_enabled()) { 122 latency_ns = qtest_latency_ns; 123 } 124 125 stats->total_time_ns[cookie->type] += latency_ns; 126 stats->last_access_time_ns = time_ns; 127 128 QSLIST_FOREACH(s, &stats->intervals, entries) { 129 timed_average_account(&s->latency[cookie->type], latency_ns); 130 } 131 } 132 } 133 134 void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type) 135 { 136 assert(type < BLOCK_MAX_IOTYPE); 137 138 /* block_acct_done() and block_acct_failed() update 139 * total_time_ns[], but this one does not. The reason is that 140 * invalid requests are accounted during their submission, 141 * therefore there's no actual I/O involved. */ 142 143 stats->invalid_ops[type]++; 144 145 if (stats->account_invalid) { 146 stats->last_access_time_ns = qemu_clock_get_ns(clock_type); 147 } 148 } 149 150 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type, 151 int num_requests) 152 { 153 assert(type < BLOCK_MAX_IOTYPE); 154 stats->merged[type] += num_requests; 155 } 156 157 int64_t block_acct_idle_time_ns(BlockAcctStats *stats) 158 { 159 return qemu_clock_get_ns(clock_type) - stats->last_access_time_ns; 160 } 161 162 double block_acct_queue_depth(BlockAcctTimedStats *stats, 163 enum BlockAcctType type) 164 { 165 uint64_t sum, elapsed; 166 167 assert(type < BLOCK_MAX_IOTYPE); 168 169 sum = timed_average_sum(&stats->latency[type], &elapsed); 170 171 return (double) sum / elapsed; 172 } 173