include/block/accounting.h

   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