ceph/src/spdk/dpdk/lib/librte_sched/rte_approx.h

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #ifndef __INCLUDE_RTE_APPROX_H__
   6 #define __INCLUDE_RTE_APPROX_H__
   7
   8 #ifdef __cplusplus
   9 extern "C" {
  10 #endif
  11
  12 /**
  13  * @file
  14  * RTE Rational Approximation
  15  *
  16  * Given a rational number alpha with 0 < alpha < 1 and a precision d, the goal
  17  * is to find positive integers p, q such that alpha - d < p/q < alpha + d, and
  18  * q is minimal.
  19  *
  20  ***/
  21
  22 #include <stdint.h>
  23
  24 /**
  25  * Find best rational approximation
  26  *
  27  * @param alpha
  28  *   Rational number to approximate
  29  * @param d
  30  *   Precision for the rational approximation
  31  * @param p
  32  *   Pointer to pre-allocated space where the numerator of the rational
  33  *   approximation will be stored when operation is successful
  34  * @param q
  35  *   Pointer to pre-allocated space where the denominator of the rational
  36  *   approximation will be stored when operation is successful
  37  * @return
  38  *   0 upon success, error code otherwise
  39  */
  40 int rte_approx(double alpha, double d, uint32_t *p, uint32_t *q);
  41
  42 #ifdef __cplusplus
  43 }
  44 #endif
  45
  46 #endif /* __INCLUDE_RTE_APPROX_H__ */