xref: /openbmc/qemu/include/block/accounting.h (revision 4b9fa0b4)
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_NONE = 0,
37     BLOCK_ACCT_READ,
38     BLOCK_ACCT_WRITE,
39     BLOCK_ACCT_FLUSH,
40     BLOCK_ACCT_UNMAP,
41     BLOCK_MAX_IOTYPE,
42 };
43 
44 struct BlockAcctTimedStats {
45     BlockAcctStats *stats;
46     TimedAverage latency[BLOCK_MAX_IOTYPE];
47     unsigned interval_length; /* in seconds */
48     QSLIST_ENTRY(BlockAcctTimedStats) entries;
49 };
50 
51 typedef struct BlockLatencyHistogram {
52     /* The following histogram is represented like this:
53      *
54      * 5|           *
55      * 4|           *
56      * 3| *         *
57      * 2| *         *    *
58      * 1| *    *    *    *
59      *  +------------------
60      *      10   50   100
61      *
62      * BlockLatencyHistogram histogram = {
63      *     .nbins = 4,
64      *     .boundaries = {10, 50, 100},
65      *     .bins = {3, 1, 5, 2},
66      * };
67      *
68      * @boundaries array define histogram intervals as follows:
69      * [0, boundaries[0]), [boundaries[0], boundaries[1]), ...
70      * [boundaries[nbins-2], +inf)
71      *
72      * So, for example above, histogram intervals are:
73      * [0, 10), [10, 50), [50, 100), [100, +inf)
74      */
75     int nbins;
76     uint64_t *boundaries; /* @nbins-1 numbers here
77                              (all boundaries, except 0 and +inf) */
78     uint64_t *bins;
79 } BlockLatencyHistogram;
80 
81 struct BlockAcctStats {
82     QemuMutex lock;
83     uint64_t nr_bytes[BLOCK_MAX_IOTYPE];
84     uint64_t nr_ops[BLOCK_MAX_IOTYPE];
85     uint64_t invalid_ops[BLOCK_MAX_IOTYPE];
86     uint64_t failed_ops[BLOCK_MAX_IOTYPE];
87     uint64_t total_time_ns[BLOCK_MAX_IOTYPE];
88     uint64_t merged[BLOCK_MAX_IOTYPE];
89     int64_t last_access_time_ns;
90     QSLIST_HEAD(, BlockAcctTimedStats) intervals;
91     bool account_invalid;
92     bool account_failed;
93     BlockLatencyHistogram latency_histogram[BLOCK_MAX_IOTYPE];
94 };
95 
96 typedef struct BlockAcctCookie {
97     int64_t bytes;
98     int64_t start_time_ns;
99     enum BlockAcctType type;
100 } BlockAcctCookie;
101 
102 void block_acct_init(BlockAcctStats *stats);
103 void block_acct_setup(BlockAcctStats *stats, bool account_invalid,
104                      bool account_failed);
105 void block_acct_cleanup(BlockAcctStats *stats);
106 void block_acct_add_interval(BlockAcctStats *stats, unsigned interval_length);
107 BlockAcctTimedStats *block_acct_interval_next(BlockAcctStats *stats,
108                                               BlockAcctTimedStats *s);
109 void block_acct_start(BlockAcctStats *stats, BlockAcctCookie *cookie,
110                       int64_t bytes, enum BlockAcctType type);
111 void block_acct_done(BlockAcctStats *stats, BlockAcctCookie *cookie);
112 void block_acct_failed(BlockAcctStats *stats, BlockAcctCookie *cookie);
113 void block_acct_invalid(BlockAcctStats *stats, enum BlockAcctType type);
114 void block_acct_merge_done(BlockAcctStats *stats, enum BlockAcctType type,
115                            int num_requests);
116 int64_t block_acct_idle_time_ns(BlockAcctStats *stats);
117 double block_acct_queue_depth(BlockAcctTimedStats *stats,
118                               enum BlockAcctType type);
119 int block_latency_histogram_set(BlockAcctStats *stats, enum BlockAcctType type,
120                                 uint64List *boundaries);
121 void block_latency_histograms_clear(BlockAcctStats *stats);
122 
123 #endif
124