1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2017 Intel Corporation
3 */
4
5 #include <rte_common.h>
6 #include <rte_ethdev.h>
7 #include <rte_malloc.h>
8 #include <rte_metrics.h>
9 #include <rte_bitrate.h>
10
11 /*
12 * Persistent bit-rate data.
13 * @internal
14 */
15 struct rte_stats_bitrate {
16 uint64_t last_ibytes;
17 uint64_t last_obytes;
18 uint64_t peak_ibits;
19 uint64_t peak_obits;
20 uint64_t mean_ibits;
21 uint64_t mean_obits;
22 uint64_t ewma_ibits;
23 uint64_t ewma_obits;
24 };
25
26 struct rte_stats_bitrates {
27 struct rte_stats_bitrate port_stats[RTE_MAX_ETHPORTS];
28 uint16_t id_stats_set;
29 };
30
31 struct rte_stats_bitrates *
rte_stats_bitrate_create(void)32 rte_stats_bitrate_create(void)
33 {
34 return rte_zmalloc(NULL, sizeof(struct rte_stats_bitrates),
35 RTE_CACHE_LINE_SIZE);
36 }
37
38 void
rte_stats_bitrate_free(struct rte_stats_bitrates * bitrate_data)39 rte_stats_bitrate_free(struct rte_stats_bitrates *bitrate_data)
40 {
41 rte_free(bitrate_data);
42 }
43
44 int
rte_stats_bitrate_reg(struct rte_stats_bitrates * bitrate_data)45 rte_stats_bitrate_reg(struct rte_stats_bitrates *bitrate_data)
46 {
47 const char * const names[] = {
48 "ewma_bits_in", "ewma_bits_out",
49 "mean_bits_in", "mean_bits_out",
50 "peak_bits_in", "peak_bits_out",
51 };
52 int return_value;
53
54 if (bitrate_data == NULL)
55 return -EINVAL;
56
57 return_value = rte_metrics_reg_names(&names[0], RTE_DIM(names));
58 if (return_value >= 0) {
59 bitrate_data->id_stats_set = return_value;
60 return 0;
61 }
62 return return_value;
63 }
64
65 int
rte_stats_bitrate_calc(struct rte_stats_bitrates * bitrate_data,uint16_t port_id)66 rte_stats_bitrate_calc(struct rte_stats_bitrates *bitrate_data,
67 uint16_t port_id)
68 {
69 struct rte_stats_bitrate *port_data;
70 struct rte_eth_stats eth_stats;
71 int ret_code;
72 uint64_t cnt_bits;
73 int64_t delta;
74 const int64_t alpha_percent = 20;
75 uint64_t values[6];
76 int ret;
77
78 if (bitrate_data == NULL)
79 return -EINVAL;
80
81 ret_code = rte_eth_stats_get(port_id, ð_stats);
82 if (ret_code != 0)
83 return ret_code < 0 ? ret_code : -ret_code;
84
85 port_data = &bitrate_data->port_stats[port_id];
86
87 /* Incoming bitrate. This is an iteratively calculated EWMA
88 * (Exponentially Weighted Moving Average) that uses a
89 * weighting factor of alpha_percent. An unsmoothed mean
90 * for just the current time delta is also calculated for the
91 * benefit of people who don't understand signal processing.
92 */
93 cnt_bits = (eth_stats.ibytes - port_data->last_ibytes) << 3;
94 port_data->last_ibytes = eth_stats.ibytes;
95 if (cnt_bits > port_data->peak_ibits)
96 port_data->peak_ibits = cnt_bits;
97 delta = cnt_bits;
98 delta -= port_data->ewma_ibits;
99 /* The +-50 fixes integer rounding during division */
100 if (delta > 0)
101 delta = (delta * alpha_percent + 50) / 100;
102 else
103 delta = (delta * alpha_percent - 50) / 100;
104 port_data->ewma_ibits += delta;
105 /* Integer roundoff prevents EWMA between 0 and (100/alpha_percent)
106 * ever reaching zero in no-traffic conditions
107 */
108 if (cnt_bits == 0 && delta == 0)
109 port_data->ewma_ibits = 0;
110 port_data->mean_ibits = cnt_bits;
111
112 /* Outgoing bitrate (also EWMA) */
113 cnt_bits = (eth_stats.obytes - port_data->last_obytes) << 3;
114 port_data->last_obytes = eth_stats.obytes;
115 if (cnt_bits > port_data->peak_obits)
116 port_data->peak_obits = cnt_bits;
117 delta = cnt_bits;
118 delta -= port_data->ewma_obits;
119 if (delta > 0)
120 delta = (delta * alpha_percent + 50) / 100;
121 else
122 delta = (delta * alpha_percent - 50) / 100;
123 port_data->ewma_obits += delta;
124 if (cnt_bits == 0 && delta == 0)
125 port_data->ewma_obits = 0;
126 port_data->mean_obits = cnt_bits;
127
128 values[0] = port_data->ewma_ibits;
129 values[1] = port_data->ewma_obits;
130 values[2] = port_data->mean_ibits;
131 values[3] = port_data->mean_obits;
132 values[4] = port_data->peak_ibits;
133 values[5] = port_data->peak_obits;
134 ret = rte_metrics_update_values(port_id, bitrate_data->id_stats_set,
135 values, RTE_DIM(values));
136 if (ret < 0)
137 return ret;
138
139 return 0;
140 }
141