1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2017 Cavium, Inc
3 */
4
5 #include "test.h"
6
7 #include <stdio.h>
8 #include <unistd.h>
9 #include <inttypes.h>
10
11 #include <rte_common.h>
12 #include <rte_cycles.h>
13 #include <rte_random.h>
14 #include <rte_reciprocal.h>
15
16 #define MAX_ITERATIONS (1ULL << 32)
17 #define DIVIDE_ITER (1ULL << 28)
18
19 static int
test_reciprocal_division_perf(void)20 test_reciprocal_division_perf(void)
21 {
22 int result = 0;
23 uint32_t divisor_u32 = 0;
24 uint32_t dividend_u32;
25 uint64_t divisor_u64 = 0;
26 uint64_t dividend_u64;
27 volatile uint32_t nresult_u32;
28 volatile uint32_t rresult_u32;
29 volatile uint64_t nresult_u64;
30 volatile uint64_t rresult_u64;
31 uint64_t start_cyc;
32 uint64_t split_cyc;
33 uint64_t end_cyc;
34 uint64_t tot_cyc_n = 0;
35 uint64_t tot_cyc_r = 0;
36 uint64_t i;
37 struct rte_reciprocal reci_u32 = {0};
38 struct rte_reciprocal_u64 reci_u64 = {0};
39
40 rte_srand(rte_rdtsc());
41
42 printf("Validating unsigned 32bit division.\n");
43 for (i = 0; i < MAX_ITERATIONS; i++) {
44 /* Change divisor every DIVIDE_ITER iterations. */
45 if (i % DIVIDE_ITER == 0) {
46 divisor_u32 = rte_rand();
47 reci_u32 = rte_reciprocal_value(divisor_u32);
48 }
49
50 dividend_u32 = rte_rand();
51
52 start_cyc = rte_rdtsc();
53 nresult_u32 = dividend_u32 / divisor_u32;
54 split_cyc = rte_rdtsc();
55 rresult_u32 = rte_reciprocal_divide(dividend_u32,
56 reci_u32);
57 end_cyc = rte_rdtsc();
58
59 tot_cyc_n += split_cyc - start_cyc;
60 tot_cyc_r += end_cyc - split_cyc;
61 if (nresult_u32 != rresult_u32) {
62 printf("Division failed, expected %"PRIu32" "
63 "result %"PRIu32"",
64 nresult_u32, rresult_u32);
65 result = 1;
66 break;
67 }
68 }
69 printf("32bit Division results:\n");
70 printf("Total number of cycles normal division : %"PRIu64"\n",
71 tot_cyc_n);
72 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
73 tot_cyc_r);
74 printf("Cycles per division(normal) : %3.2f\n",
75 ((double)tot_cyc_n)/i);
76 printf("Cycles per division(reciprocal) : %3.2f\n\n",
77 ((double)tot_cyc_r)/i);
78
79 tot_cyc_n = 0;
80 tot_cyc_r = 0;
81
82 printf("Validating unsigned 64bit division.\n");
83 for (i = 0; i < MAX_ITERATIONS; i++) {
84 /* Change divisor every DIVIDE_ITER iterations. */
85 if (i % DIVIDE_ITER == 0) {
86 divisor_u64 = rte_rand();
87 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
88 }
89
90 dividend_u64 = rte_rand();
91
92 start_cyc = rte_rdtsc();
93 nresult_u64 = dividend_u64 / divisor_u64;
94 split_cyc = rte_rdtsc();
95 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
96 &reci_u64);
97 end_cyc = rte_rdtsc();
98
99 tot_cyc_n += split_cyc - start_cyc;
100 tot_cyc_r += end_cyc - split_cyc;
101 if (nresult_u64 != rresult_u64) {
102 printf("Division failed, expected %"PRIu64" "
103 "result %"PRIu64"",
104 nresult_u64, rresult_u64);
105 result = 1;
106 break;
107 }
108 }
109 printf("64bit Division results:\n");
110 printf("Total number of cycles normal division : %"PRIu64"\n",
111 tot_cyc_n);
112 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
113 tot_cyc_r);
114 printf("Cycles per division(normal) : %3.2f\n",
115 ((double)tot_cyc_n)/i);
116 printf("Cycles per division(reciprocal) : %3.2f\n\n",
117 ((double)tot_cyc_r)/i);
118
119 tot_cyc_n = 0;
120 tot_cyc_r = 0;
121
122 printf("Validating unsigned 64bit division with 32bit divisor.\n");
123 for (i = 0; i < MAX_ITERATIONS; i++) {
124 /* Change divisor every DIVIDE_ITER iterations. */
125 if (i % DIVIDE_ITER == 0) {
126 divisor_u64 = rte_rand() >> 32;
127 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
128 }
129
130 dividend_u64 = rte_rand();
131
132 start_cyc = rte_rdtsc();
133 nresult_u64 = dividend_u64 / divisor_u64;
134 split_cyc = rte_rdtsc();
135 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
136 &reci_u64);
137 end_cyc = rte_rdtsc();
138
139 tot_cyc_n += split_cyc - start_cyc;
140 tot_cyc_r += end_cyc - split_cyc;
141 if (nresult_u64 != rresult_u64) {
142 printf("Division failed, expected %"PRIu64" "
143 "result %"PRIu64"",
144 nresult_u64, rresult_u64);
145 result = 1;
146 break;
147 }
148 }
149
150 printf("64bit Division results:\n");
151 printf("Total number of cycles normal division : %"PRIu64"\n",
152 tot_cyc_n);
153 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
154 tot_cyc_r);
155 printf("Cycles per division(normal) : %3.2f\n",
156 ((double)tot_cyc_n)/i);
157 printf("Cycles per division(reciprocal) : %3.2f\n\n",
158 ((double)tot_cyc_r)/i);
159
160 tot_cyc_n = 0;
161 tot_cyc_r = 0;
162
163 printf("Validating division by power of 2.\n");
164 for (i = 0; i < 64; i++) {
165 divisor_u64 = 1ull << i;
166 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
167
168 dividend_u64 = rte_rand();
169
170 start_cyc = rte_rdtsc();
171 nresult_u64 = dividend_u64 / divisor_u64;
172 split_cyc = rte_rdtsc();
173 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
174 &reci_u64);
175 end_cyc = rte_rdtsc();
176
177 tot_cyc_n += split_cyc - start_cyc;
178 tot_cyc_r += end_cyc - split_cyc;
179 if (nresult_u64 != rresult_u64) {
180 printf("Division 64 failed, %"PRIu64"/%"PRIu64" = "
181 "expected %"PRIu64" result %"PRIu64"\n",
182 dividend_u64, divisor_u64,
183 nresult_u64, rresult_u64);
184 result = 1;
185 break;
186 }
187 }
188 printf("64bit Division results:\n");
189 printf("Total number of cycles normal division : %"PRIu64"\n",
190 tot_cyc_n);
191 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
192 tot_cyc_r);
193 printf("Cycles per division(normal) : %3.2f\n",
194 ((double)tot_cyc_n)/i);
195 printf("Cycles per division(reciprocal) : %3.2f\n",
196 ((double)tot_cyc_r)/i);
197
198 return result;
199 }
200
201 REGISTER_TEST_COMMAND(reciprocal_division_perf, test_reciprocal_division_perf);
202