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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 |