| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Benchmarking support |
| 4 | * |
| 5 | * (c) 2023 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of the mLib utilities library. |
| 11 | * |
| 12 | * mLib is free software: you can redistribute it and/or modify it under |
| 13 | * the terms of the GNU Library General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or (at |
| 15 | * your option) any later version. |
| 16 | * |
| 17 | * mLib is distributed in the hope that it will be useful, but WITHOUT |
| 18 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public |
| 20 | * License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with mLib. If not, write to the Free Software |
| 24 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
| 25 | * USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef MLIB_BENCH_H |
| 29 | #define MLIB_BENCH_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #ifndef MLIB_BITS_H |
| 38 | # include "bits.h" |
| 39 | #endif |
| 40 | |
| 41 | /*----- Data structures ---------------------------------------------------*/ |
| 42 | |
| 43 | struct bench_time { |
| 44 | unsigned f; /* flags */ |
| 45 | #define BTF_TIMEOK 1u /* @s@ ad @ns@ slots are value */ |
| 46 | #define BTF_CYOK 2u /* @cy@ slot is valid */ |
| 47 | #define BTF_ANY (BTF_TIMEOK | BTF_CYOK) /* some part is useful */ |
| 48 | kludge64 s; uint32 ns; /* real time in seconds and nanos */ |
| 49 | kludge64 cy; /* count of CPU cycles */ |
| 50 | }; |
| 51 | |
| 52 | struct bench_timing { |
| 53 | unsigned f; /* flags (as in @struct bench_time@) */ |
| 54 | double n, t, cy; /* count, time, and cycles */ |
| 55 | }; |
| 56 | |
| 57 | struct bench_timer { const struct bench_timerops *ops; }; |
| 58 | |
| 59 | struct bench_timerops { |
| 60 | void (*now)(struct bench_timer */*bt*/, struct bench_time */*t_out*/); |
| 61 | /* Fill in @*t_out@ with the current time. v*/ |
| 62 | |
| 63 | void (*destroy)(struct bench_timer */*bt*/); |
| 64 | /* Release the timer and any resources it holds. */ |
| 65 | }; |
| 66 | |
| 67 | struct bench_state { |
| 68 | struct bench_timer *tm; /* a timer */ |
| 69 | double target_s; /* target time to run benchmarks */ |
| 70 | unsigned f; /* flags (@BTF_...@) for calibrations */ |
| 71 | struct { double m, c; } clk, cy; /* calculated overheads */ |
| 72 | }; |
| 73 | |
| 74 | typedef void bench_fn(unsigned long /*n*/, void */*ctx*/); |
| 75 | /* Run the benchmark @n@ times, given a context pointer @ctx@. */ |
| 76 | |
| 77 | /*----- Functions provided ------------------------------------------------*/ |
| 78 | |
| 79 | /* --- @bench_createtimer@ --- * |
| 80 | * |
| 81 | * Arguments: --- |
| 82 | * |
| 83 | * Returns: A freshly constructed standard timer object. |
| 84 | * |
| 85 | * Use: Allocate a timer. Dispose of it by calling |
| 86 | * @tm->ops->destroy(tm)@ when you're done. |
| 87 | */ |
| 88 | |
| 89 | extern struct bench_timer *bench_createtimer(void); |
| 90 | |
| 91 | /* --- @bench_init@ --- * |
| 92 | * |
| 93 | * Arguments: @struct bench_state *b@ = bench state to initialize |
| 94 | * @struct bench_timer *tm@ = timer to attach |
| 95 | * |
| 96 | * Returns: --- |
| 97 | * |
| 98 | * Use: Initialize the benchmark state. It still needs to be |
| 99 | * calibrated (use @bench_calibrate@) before it can be used, but |
| 100 | * this will be done automatically by @bench_measure@ if it's |
| 101 | * not done by hand earlier. The timer is now owned by the |
| 102 | * benchmark state and will be destroyed by @bench_destroy@. |
| 103 | */ |
| 104 | |
| 105 | extern void bench_init(struct bench_state */*b*/, |
| 106 | struct bench_timer */*tm*/); |
| 107 | |
| 108 | /* --- @bench_destroy@ --- * |
| 109 | * |
| 110 | * Arguments: @struct bench_state *b@ = bench state |
| 111 | * |
| 112 | * Returns: --- |
| 113 | * |
| 114 | * Use: Destroy the benchmark state, releasing the resources that it |
| 115 | * holds. |
| 116 | */ |
| 117 | |
| 118 | extern void bench_destroy(struct bench_state */*b*/); |
| 119 | |
| 120 | /* --- @bench_calibrate@ --- * |
| 121 | * |
| 122 | * Arguments: @struct bench_state *b@ = bench state |
| 123 | * |
| 124 | * Returns: Zero on success, @-1@ if calibration failed. |
| 125 | * |
| 126 | * Use: Calibrate the benchmark state, so that it can be used to |
| 127 | * measure performance reasonably accurately. |
| 128 | */ |
| 129 | |
| 130 | extern int bench_calibrate(struct bench_state */*b*/); |
| 131 | |
| 132 | /* --- @bench_measure@ --- * |
| 133 | * |
| 134 | * Arguments: @struct bench_timing *t_out@ = where to leave the timing |
| 135 | * @struct bench_state *b@ = benchmark state |
| 136 | * @double base@ = number of internal units per call |
| 137 | * @bench_fn *fn@, @void *ctx@ = benchmark function to run |
| 138 | * |
| 139 | * Returns: Zero on success, @-1@ if timing failed. |
| 140 | * |
| 141 | * Use: Measure a function. The function @fn@ is called adaptively |
| 142 | * with an iteration count @n@ set so as to run for |
| 143 | * approximately @b->target_s@ seconds. |
| 144 | * |
| 145 | * The result is left in @*t_out@, with @t_out->n@ counting the |
| 146 | * final product of the iteration count and @base@ (which might, |
| 147 | * e.g., reflect the number of inner iterations the function |
| 148 | * performs, or the number of bytes it processes per iteration). |
| 149 | */ |
| 150 | |
| 151 | extern int bench_measure(struct bench_timing */*t_out*/, |
| 152 | struct bench_state */*b*/, |
| 153 | double /*base*/, bench_fn */*fn*/, void */*ctx*/); |
| 154 | |
| 155 | /*----- That's all, folks -------------------------------------------------*/ |
| 156 | |
| 157 | #ifdef __cplusplus |
| 158 | } |
| 159 | #endif |
| 160 | |
| 161 | #endif |