xref: /openbmc/qemu/include/block/accounting.h (revision 520e210c)
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 #ifndef BLOCK_ACCOUNTING_H
26 #define BLOCK_ACCOUNTING_H
27 
28 #include "qemu/timed-average.h"
29 #include "qemu/thread.h"
30 #include "qapi/qapi-builtin-types.h"
31 
32 typedef struct BlockAcctTimedStats BlockAcctTimedStats;
33 typedef struct BlockAcctStats BlockAcctStats;
34 
35 enum BlockAcctType {
36     BLOCK_ACCT_READ,
37     BLOCK_ACCT_WRITE,
38     BLOCK_ACCT_FLUSH,
39     BLOCK_MAX_IOTYPE,
40 };
41 
42 struct BlockAcctTimedStats {
43     BlockAcctStats *stats;
44     TimedAverage latency[BLOCK_MAX_IOTYPE];
45     unsigned interval_length; /* in seconds */
46     QSLIST_ENTRY(BlockAcctTimedStats) entries;
47 };
48 
49 typedef struct BlockLatencyHistogram {
50     /* The following histogram is represented like this:
51      *
52      * 5|           *
53      * 4|           *
54      * 3| *         *
55      * 2| *         *    *
56      * 1| *    *    *    *
57      *  +------------------
58      *      10   50   100
59      *
60      * BlockLatencyHistogram histogram = {
61      *     .nbins = 4,
62      *     .boundaries = {10, 50, 100},
63      *     .bins = {3, 1, 5, 2},
64      * };
65      *
66      * @boundaries array define histogram intervals as follows:
67      * [0, boundaries[0]), [boundaries[0], boundaries[1]), ...
68      * [boundaries[nbins-2], +inf)
69      *
70      * So, for example above, histogram intervals are:
71      * [0, 10), [10, 50), [50, 100), [100, +inf)
72      */
73     int nbins;
74     uint64_t *boundaries; /* @nbins-1 numbers here
75                              (all boundaries, except 0 and +inf) */
76     uint64_t *bins;
77 } BlockLatencyHistogram;
78 
79 struct BlockAcctStats {
80     QemuMutex lock;
81     uint64_t nr_bytes[BLOCK_MAX_IOTYPE];
82     uint64_t nr_ops[BLOCK_MAX_IOTYPE];
83     uint64_t invalid_ops[BLOCK_MAX_IOTYPE];
84     uint64_t failed_ops[BLOCK_MAX_IOTYPE];
85     uint64_t total_time_ns[BLOCK_MAX_IOTYPE];
86     uint64_t merged[BLOCK_MAX_IOTYPE];
87     int64_t last_access_time_ns;
88     QSLIST_HEAD(, BlockAcctTimedStats) intervals;
89     bool account_invalid;
90     bool account_failed;
91     BlockLatencyHistogram latency_histogram[BLOCK_MAX_IOTYPE];
92 };
93 
94 typedef struct BlockAcctCookie {
95     int64_t bytes;
96     int64_t start_time_ns;
97     enum BlockAcctType type;
98 } BlockAcctCookie;
99 
100 void block_acct_init(BlockAcctStats *stats);
101 void block_acct_setup(BlockAcctStats *stats, bool account_invalid,
102                      bool account_failed);
103 void block_acct_cleanup(BlockAcctStats *stats);
104 void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length);
105 BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats,
106                                               BlockAcctTimedStats *s);
107 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
108                       int64_t bytes, enum BlockAcctType type);
109 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie);
110 void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie);
111 void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type);
112 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
113                            int num_requests);
114 int64_t block_acct_idle_time_ns(BlockAcctStats *stats);
115 double block_acct_queue_depth(BlockAcctTimedStats *stats,
116                               enum BlockAcctType type);
117 int block_latency_histogram_set(BlockAcctStats *stats, enum BlockAcctType type,
118                                 uint64List *boundaries);
119 void block_latency_histograms_clear(BlockAcctStats *stats);
120 
121 #endif
122