| 1 | /* |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
| 8 | * You may select, at your option, one of the above-listed licenses. |
| 9 | */ |
| 10 | |
| 11 | |
| 12 | /* benchfn : |
| 13 | * benchmark any function on a set of input |
| 14 | * providing result in nanoSecPerRun |
| 15 | * or detecting and returning an error |
| 16 | */ |
| 17 | |
| 18 | #if defined (__cplusplus) |
| 19 | extern "C" { |
| 20 | #endif |
| 21 | |
| 22 | #ifndef BENCH_FN_H_23876 |
| 23 | #define BENCH_FN_H_23876 |
| 24 | |
| 25 | /* === Dependencies === */ |
| 26 | #include <stddef.h> /* size_t */ |
| 27 | |
| 28 | |
| 29 | /* ==== Benchmark any function, iterated on a set of blocks ==== */ |
| 30 | |
| 31 | /* BMK_runTime_t: valid result return type */ |
| 32 | |
| 33 | typedef struct { |
| 34 | double nanoSecPerRun; /* time per iteration (over all blocks) */ |
| 35 | size_t sumOfReturn; /* sum of return values */ |
| 36 | } BMK_runTime_t; |
| 37 | |
| 38 | |
| 39 | /* BMK_runOutcome_t: |
| 40 | * type expressing the outcome of a benchmark run by BMK_benchFunction(), |
| 41 | * which can be either valid or invalid. |
| 42 | * benchmark outcome can be invalid if errorFn is provided. |
| 43 | * BMK_runOutcome_t must be considered "opaque" : never access its members directly. |
| 44 | * Instead, use its assigned methods : |
| 45 | * BMK_isSuccessful_runOutcome, BMK_extract_runTime, BMK_extract_errorResult. |
| 46 | * The structure is only described here to allow its allocation on stack. */ |
| 47 | |
| 48 | typedef struct { |
| 49 | BMK_runTime_t internal_never_ever_use_directly; |
| 50 | size_t error_result_never_ever_use_directly; |
| 51 | int error_tag_never_ever_use_directly; |
| 52 | } BMK_runOutcome_t; |
| 53 | |
| 54 | |
| 55 | /* prototypes for benchmarked functions */ |
| 56 | typedef size_t (*BMK_benchFn_t)(const void* src, size_t srcSize, void* dst, size_t dstCapacity, void* customPayload); |
| 57 | typedef size_t (*BMK_initFn_t)(void* initPayload); |
| 58 | typedef unsigned (*BMK_errorFn_t)(size_t); |
| 59 | |
| 60 | |
| 61 | /* BMK_benchFunction() parameters are provided via the following structure. |
| 62 | * A structure is preferable for readability, |
| 63 | * as the number of parameters required is fairly large. |
| 64 | * No initializer is provided, because it doesn't make sense to provide some "default" : |
| 65 | * all parameters must be specified by the caller. |
| 66 | * optional parameters are labelled explicitly, and accept value NULL when not used */ |
| 67 | typedef struct { |
| 68 | BMK_benchFn_t benchFn; /* the function to benchmark, over the set of blocks */ |
| 69 | void* benchPayload; /* pass custom parameters to benchFn : |
| 70 | * (*benchFn)(srcBuffers[i], srcSizes[i], dstBuffers[i], dstCapacities[i], benchPayload) */ |
| 71 | BMK_initFn_t initFn; /* (*initFn)(initPayload) is run once per run, at the beginning. */ |
| 72 | void* initPayload; /* Both arguments can be NULL, in which case nothing is run. */ |
| 73 | BMK_errorFn_t errorFn; /* errorFn will check each return value of benchFn over each block, to determine if it failed or not. |
| 74 | * errorFn can be NULL, in which case no check is performed. |
| 75 | * errorFn must return 0 when benchFn was successful, and >= 1 if it detects an error. |
| 76 | * Execution is stopped as soon as an error is detected. |
| 77 | * the triggering return value can be retrieved using BMK_extract_errorResult(). */ |
| 78 | size_t blockCount; /* number of blocks to operate benchFn on. |
| 79 | * It's also the size of all array parameters : |
| 80 | * srcBuffers, srcSizes, dstBuffers, dstCapacities, blockResults */ |
| 81 | const void *const * srcBuffers; /* read-only array of buffers to be operated on by benchFn */ |
| 82 | const size_t* srcSizes; /* read-only array containing sizes of srcBuffers */ |
| 83 | void *const * dstBuffers; /* array of buffers to be written into by benchFn. This array is not optional, it must be provided even if unused by benchfn. */ |
| 84 | const size_t* dstCapacities; /* read-only array containing capacities of dstBuffers. This array must be present. */ |
| 85 | size_t* blockResults; /* Optional: store the return value of benchFn for each block. Use NULL if this result is not requested. */ |
| 86 | } BMK_benchParams_t; |
| 87 | |
| 88 | |
| 89 | /* BMK_benchFunction() : |
| 90 | * This function benchmarks benchFn and initFn, providing a result. |
| 91 | * |
| 92 | * params : see description of BMK_benchParams_t above. |
| 93 | * nbLoops: defines number of times benchFn is run over the full set of blocks. |
| 94 | * Minimum value is 1. A 0 is interpreted as a 1. |
| 95 | * |
| 96 | * @return: can express either an error or a successful result. |
| 97 | * Use BMK_isSuccessful_runOutcome() to check if benchmark was successful. |
| 98 | * If yes, extract the result with BMK_extract_runTime(), |
| 99 | * it will contain : |
| 100 | * .sumOfReturn : the sum of all return values of benchFn through all of blocks |
| 101 | * .nanoSecPerRun : time per run of benchFn + (time for initFn / nbLoops) |
| 102 | * .sumOfReturn is generally intended for functions which return a # of bytes written into dstBuffer, |
| 103 | * in which case, this value will be the total amount of bytes written into dstBuffer. |
| 104 | * |
| 105 | * blockResults : when provided (!= NULL), and when benchmark is successful, |
| 106 | * params.blockResults contains all return values of `benchFn` over all blocks. |
| 107 | * when provided (!= NULL), and when benchmark failed, |
| 108 | * params.blockResults contains return values of `benchFn` over all blocks preceding and including the failed block. |
| 109 | */ |
| 110 | BMK_runOutcome_t BMK_benchFunction(BMK_benchParams_t params, unsigned nbLoops); |
| 111 | |
| 112 | |
| 113 | |
| 114 | /* check first if the benchmark was successful or not */ |
| 115 | int BMK_isSuccessful_runOutcome(BMK_runOutcome_t outcome); |
| 116 | |
| 117 | /* If the benchmark was successful, extract the result. |
| 118 | * note : this function will abort() program execution if benchmark failed ! |
| 119 | * always check if benchmark was successful first ! |
| 120 | */ |
| 121 | BMK_runTime_t BMK_extract_runTime(BMK_runOutcome_t outcome); |
| 122 | |
| 123 | /* when benchmark failed, it means one invocation of `benchFn` failed. |
| 124 | * The failure was detected by `errorFn`, operating on return values of `benchFn`. |
| 125 | * Returns the faulty return value. |
| 126 | * note : this function will abort() program execution if benchmark did not fail. |
| 127 | * always check if benchmark failed first ! |
| 128 | */ |
| 129 | size_t BMK_extract_errorResult(BMK_runOutcome_t outcome); |
| 130 | |
| 131 | |
| 132 | |
| 133 | /* ==== Benchmark any function, returning intermediate results ==== */ |
| 134 | |
| 135 | /* state information tracking benchmark session */ |
| 136 | typedef struct BMK_timedFnState_s BMK_timedFnState_t; |
| 137 | |
| 138 | /* BMK_benchTimedFn() : |
| 139 | * Similar to BMK_benchFunction(), most arguments being identical. |
| 140 | * Automatically determines `nbLoops` so that each result is regularly produced at interval of about run_ms. |
| 141 | * Note : minimum `nbLoops` is 1, therefore a run may last more than run_ms, and possibly even more than total_ms. |
| 142 | * Usage - initialize timedFnState, select benchmark duration (total_ms) and each measurement duration (run_ms) |
| 143 | * call BMK_benchTimedFn() repetitively, each measurement is supposed to last about run_ms |
| 144 | * Check if total time budget is spent or exceeded, using BMK_isCompleted_TimedFn() |
| 145 | */ |
| 146 | BMK_runOutcome_t BMK_benchTimedFn(BMK_timedFnState_t* timedFnState, |
| 147 | BMK_benchParams_t params); |
| 148 | |
| 149 | /* Tells if duration of all benchmark runs has exceeded total_ms |
| 150 | */ |
| 151 | int BMK_isCompleted_TimedFn(const BMK_timedFnState_t* timedFnState); |
| 152 | |
| 153 | /* BMK_createTimedFnState() and BMK_resetTimedFnState() : |
| 154 | * Create/Set BMK_timedFnState_t for next benchmark session, |
| 155 | * which shall last a minimum of total_ms milliseconds, |
| 156 | * producing intermediate results, paced at interval of (approximately) run_ms. |
| 157 | */ |
| 158 | BMK_timedFnState_t* BMK_createTimedFnState(unsigned total_ms, unsigned run_ms); |
| 159 | void BMK_resetTimedFnState(BMK_timedFnState_t* timedFnState, unsigned total_ms, unsigned run_ms); |
| 160 | void BMK_freeTimedFnState(BMK_timedFnState_t* state); |
| 161 | |
| 162 | |
| 163 | /* BMK_timedFnState_shell and BMK_initStatic_timedFnState() : |
| 164 | * Makes it possible to statically allocate a BMK_timedFnState_t on stack. |
| 165 | * BMK_timedFnState_shell is only there to allocate space, |
| 166 | * never ever access its members. |
| 167 | * BMK_timedFnState_t() actually accepts any buffer. |
| 168 | * It will check if provided buffer is large enough and is correctly aligned, |
| 169 | * and will return NULL if conditions are not respected. |
| 170 | */ |
| 171 | #define BMK_TIMEDFNSTATE_SIZE 64 |
| 172 | typedef union { |
| 173 | char never_access_space[BMK_TIMEDFNSTATE_SIZE]; |
| 174 | long long alignment_enforcer; /* must be aligned on 8-bytes boundaries */ |
| 175 | } BMK_timedFnState_shell; |
| 176 | BMK_timedFnState_t* BMK_initStatic_timedFnState(void* buffer, size_t size, unsigned total_ms, unsigned run_ms); |
| 177 | |
| 178 | |
| 179 | #endif /* BENCH_FN_H_23876 */ |
| 180 | |
| 181 | #if defined (__cplusplus) |
| 182 | } |
| 183 | #endif |