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/* Licensed under LGPLv2.1+ - see LICENSE file for details */
#ifndef CCAN_JACOBSON_KARELS_H
#define CCAN_JACOBSON_KARELS_H
#include "config.h"
#include <ccan/minmax/minmax.h>
#define JACOBSON_KARELS(_name, _type, _a1, _a2, _b1, _b2, _g, _k) \
struct _name##_state { \
_type rtt, variance; \
}; \
static inline void _name##_init(struct _name##_state *s, \
_type rtt0, _type var0) \
{ \
s->rtt = rtt0; \
s->variance = var0; \
} \
static inline void _name##_update(struct _name##_state *s, _type sample) \
{ \
_type diff = sample - s->rtt; \
s->rtt += (_a2) * diff / ((_a1) + (_a2)); \
diff = (diff < 0) ? -diff : diff; \
s->variance = ((_b1)*s->variance + (_b2) * diff) \
/ ((_b1) + (_b2)); \
} \
static inline _type _name##_timeout(struct _name##_state *s, \
_type tmin, _type tmax) \
{ \
return clamp((_g) * s->rtt + (_k)*s->variance, tmin, tmax); \
}
JACOBSON_KARELS(jacobson_karels, unsigned long, 7, 1, 3, 1, 1, 4)
#endif /* CCAN_JACOBSON_KARELS_H */
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