projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 11fdf7f2 TL |
1 | /* SPDX-License-Identifier: BSD-3-Clause |
| 2 | * Copyright(c) 2010-2014 Intel Corporation | |
| 3 | */ | |
| 4 | ||
| 5 | #ifndef __INCLUDE_RTE_SCHED_COMMON_H__ | |
| 6 | #define __INCLUDE_RTE_SCHED_COMMON_H__ | |
| 7 | ||
| 8 | #ifdef __cplusplus | |
| 9 | extern "C" { | |
| 10 | #endif | |
| 11 | ||
| 12 | #include <stdint.h> | |
| 13 | #include <sys/types.h> | |
| 14 | ||
| f67539c2 | 15 | #define __rte_aligned_16 __rte_aligned(16) |
| 11fdf7f2 TL |
16 | |
| 17 | #if 0 | |
| 18 | static inline uint32_t | |
| 19 | rte_min_pos_4_u16(uint16_t *x) | |
| 20 | { | |
| 21 | uint32_t pos0, pos1; | |
| 22 | ||
| 23 | pos0 = (x[0] <= x[1])? 0 : 1; | |
| 24 | pos1 = (x[2] <= x[3])? 2 : 3; | |
| 25 | ||
| 26 | return (x[pos0] <= x[pos1])? pos0 : pos1; | |
| 27 | } | |
| 28 | ||
| 29 | #else | |
| 30 | ||
| 31 | /* simplified version to remove branches with CMOV instruction */ | |
| 32 | static inline uint32_t | |
| 33 | rte_min_pos_4_u16(uint16_t *x) | |
| 34 | { | |
| 35 | uint32_t pos0 = 0; | |
| 36 | uint32_t pos1 = 2; | |
| 37 | ||
| 38 | if (x[1] <= x[0]) pos0 = 1; | |
| 39 | if (x[3] <= x[2]) pos1 = 3; | |
| 40 | if (x[pos1] <= x[pos0]) pos0 = pos1; | |
| 41 | ||
| 42 | return pos0; | |
| 43 | } | |
| 44 | ||
| 45 | #endif | |
| 46 | ||
| 47 | /* | |
| 48 | * Compute the Greatest Common Divisor (GCD) of two numbers. | |
| 49 | * This implementation uses Euclid's algorithm: | |
| 50 | * gcd(a, 0) = a | |
| 51 | * gcd(a, b) = gcd(b, a mod b) | |
| 52 | * | |
| 53 | */ | |
| 54 | static inline uint32_t | |
| 55 | rte_get_gcd(uint32_t a, uint32_t b) | |
| 56 | { | |
| 57 | uint32_t c; | |
| 58 | ||
| 59 | if (a == 0) | |
| 60 | return b; | |
| 61 | if (b == 0) | |
| 62 | return a; | |
| 63 | ||
| 64 | if (a < b) { | |
| 65 | c = a; | |
| 66 | a = b; | |
| 67 | b = c; | |
| 68 | } | |
| 69 | ||
| 70 | while (b != 0) { | |
| 71 | c = a % b; | |
| 72 | a = b; | |
| 73 | b = c; | |
| 74 | } | |
| 75 | ||
| 76 | return a; | |
| 77 | } | |
| 78 | ||
| 79 | /* | |
| 80 | * Compute the Lowest Common Denominator (LCD) of two numbers. | |
| 81 | * This implementation computes GCD first: | |
| 82 | * LCD(a, b) = (a * b) / GCD(a, b) | |
| 83 | * | |
| 84 | */ | |
| 85 | static inline uint32_t | |
| 86 | rte_get_lcd(uint32_t a, uint32_t b) | |
| 87 | { | |
| 88 | return (a * b) / rte_get_gcd(a, b); | |
| 89 | } | |
| 90 | ||
| 91 | #ifdef __cplusplus | |
| 92 | } | |
| 93 | #endif | |
| 94 | ||
| 95 | #endif /* __INCLUDE_RTE_SCHED_COMMON_H__ */ |