1 1.2 riastrad /* $NetBSD: average.h,v 1.2 2021/12/19 10:38:38 riastradh Exp $ */ 2 1.2 riastrad 3 1.2 riastrad /*- 4 1.2 riastrad * Copyright (c) 2020 The NetBSD Foundation, Inc. 5 1.2 riastrad * All rights reserved. 6 1.2 riastrad * 7 1.2 riastrad * Redistribution and use in source and binary forms, with or without 8 1.2 riastrad * modification, are permitted provided that the following conditions 9 1.2 riastrad * are met: 10 1.2 riastrad * 1. Redistributions of source code must retain the above copyright 11 1.2 riastrad * notice, this list of conditions and the following disclaimer. 12 1.2 riastrad * 2. Redistributions in binary form must reproduce the above copyright 13 1.2 riastrad * notice, this list of conditions and the following disclaimer in the 14 1.2 riastrad * documentation and/or other materials provided with the distribution. 15 1.2 riastrad * 16 1.2 riastrad * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 1.2 riastrad * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 1.2 riastrad * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 1.2 riastrad * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 1.2 riastrad * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 1.2 riastrad * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 1.2 riastrad * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 1.2 riastrad * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 1.2 riastrad * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 1.2 riastrad * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 1.2 riastrad * POSSIBILITY OF SUCH DAMAGE. 27 1.2 riastrad */ 28 1.2 riastrad 29 1.2 riastrad #ifndef _LINUX_AVERAGE_H_ 30 1.2 riastrad #define _LINUX_AVERAGE_H_ 31 1.2 riastrad 32 1.2 riastrad #define DECLARE_EWMA(NAME, PREC, RATE) \ 33 1.2 riastrad struct ewma_##NAME { \ 34 1.2 riastrad unsigned long ewma_state; \ 35 1.2 riastrad }; \ 36 1.2 riastrad \ 37 1.2 riastrad static inline void \ 38 1.2 riastrad ewma_##NAME##_init(struct ewma_##NAME *ewma) \ 39 1.2 riastrad { \ 40 1.2 riastrad ewma->ewma_state = 0; \ 41 1.2 riastrad } \ 42 1.2 riastrad \ 43 1.2 riastrad static inline unsigned long \ 44 1.2 riastrad ewma_##NAME##_read(struct ewma_##NAME *ewma) \ 45 1.2 riastrad { \ 46 1.2 riastrad return ewma->ewma_state >> (PREC); \ 47 1.2 riastrad } \ 48 1.2 riastrad \ 49 1.2 riastrad static inline void \ 50 1.2 riastrad ewma_##NAME##_add(struct ewma_##NAME *ewma, unsigned long sample) \ 51 1.2 riastrad { \ 52 1.2 riastrad const unsigned long shift = ilog2(RATE); \ 53 1.2 riastrad const unsigned long state = ewma->ewma_state; \ 54 1.2 riastrad \ 55 1.2 riastrad sample <<= (PREC); \ 56 1.2 riastrad if (state == 0) { \ 57 1.2 riastrad ewma->ewma_state = sample; \ 58 1.2 riastrad return; \ 59 1.2 riastrad } \ 60 1.2 riastrad ewma->ewma_state = (((state << shift) - state) + sample) >> shift; \ 61 1.2 riastrad } 62 1.2 riastrad 63 1.2 riastrad #endif /* _LINUX_AVERAGE_H_ */ 64
Indexes created Sun Sep 21 20:09:37 GMT 2025