1/* SPDX-License-Identifier: GPL-2.0 */
2/**
3 * lib/minmax.c: windowed min/max tracker by Kathleen Nichols.
4 *
5 */
6#ifndef MINMAX_H
7#define MINMAX_H
8
9#include <linux/types.h>
10
11/* A single data point for our parameterized min-max tracker */
12struct minmax_sample {
13 u32 t; /* time measurement was taken */
14 u32 v; /* value measured */
15};
16
17/* State for the parameterized min-max tracker */
18struct minmax {
19 struct minmax_sample s[3];
20};
21
22static inline u32 minmax_get(const struct minmax *m)
23{
24 return m->s[0].v;
25}
26
27static inline u32 minmax_reset(struct minmax *m, u32 t, u32 meas)
28{
29 struct minmax_sample val = { .t = t, .v = meas };
30
31 m->s[2] = m->s[1] = m->s[0] = val;
32 return m->s[0].v;
33}
34
35u32 minmax_running_max(struct minmax *m, u32 win, u32 t, u32 meas);
36u32 minmax_running_min(struct minmax *m, u32 win, u32 t, u32 meas);
37
38#endif
39