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 if (i != 0) {
75 printf("Cycles per division(normal) : %3.2f\n",
76 ((double)tot_cyc_n)/i);
77 printf("Cycles per division(reciprocal) : %3.2f\n\n",
78 ((double)tot_cyc_r)/i);
79 }
80
81 tot_cyc_n = 0;
82 tot_cyc_r = 0;
83
84 printf("Validating unsigned 64bit division.\n");
85 for (i = 0; i < MAX_ITERATIONS; i++) {
86 /* Change divisor every DIVIDE_ITER iterations. */
87 if (i % DIVIDE_ITER == 0) {
88 divisor_u64 = rte_rand();
89 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
90 }
91
92 dividend_u64 = rte_rand();
93
94 start_cyc = rte_rdtsc();
95 nresult_u64 = dividend_u64 / divisor_u64;
96 split_cyc = rte_rdtsc();
97 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
98 &reci_u64);
99 end_cyc = rte_rdtsc();
100
101 tot_cyc_n += split_cyc - start_cyc;
102 tot_cyc_r += end_cyc - split_cyc;
103 if (nresult_u64 != rresult_u64) {
104 printf("Division failed, expected %"PRIu64" "
105 "result %"PRIu64"",
106 nresult_u64, rresult_u64);
107 result = 1;
108 break;
109 }
110 }
111 printf("64bit Division results:\n");
112 printf("Total number of cycles normal division : %"PRIu64"\n",
113 tot_cyc_n);
114 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
115 tot_cyc_r);
116 if (i != 0) {
117 printf("Cycles per division(normal) : %3.2f\n",
118 ((double)tot_cyc_n)/i);
119 printf("Cycles per division(reciprocal) : %3.2f\n\n",
120 ((double)tot_cyc_r)/i);
121 }
122 tot_cyc_n = 0;
123 tot_cyc_r = 0;
124
125 printf("Validating unsigned 64bit division with 32bit divisor.\n");
126 for (i = 0; i < MAX_ITERATIONS; i++) {
127 /* Change divisor every DIVIDE_ITER iterations. */
128 if (i % DIVIDE_ITER == 0) {
129 divisor_u64 = rte_rand() >> 32;
130 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
131 }
132
133 dividend_u64 = rte_rand();
134
135 start_cyc = rte_rdtsc();
136 nresult_u64 = dividend_u64 / divisor_u64;
137 split_cyc = rte_rdtsc();
138 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
139 &reci_u64);
140 end_cyc = rte_rdtsc();
141
142 tot_cyc_n += split_cyc - start_cyc;
143 tot_cyc_r += end_cyc - split_cyc;
144 if (nresult_u64 != rresult_u64) {
145 printf("Division failed, expected %"PRIu64" "
146 "result %"PRIu64"",
147 nresult_u64, rresult_u64);
148 result = 1;
149 break;
150 }
151 }
152
153 printf("64bit Division results:\n");
154 printf("Total number of cycles normal division : %"PRIu64"\n",
155 tot_cyc_n);
156 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
157 tot_cyc_r);
158 if (i != 0) {
159 printf("Cycles per division(normal) : %3.2f\n",
160 ((double)tot_cyc_n)/i);
161 printf("Cycles per division(reciprocal) : %3.2f\n\n",
162 ((double)tot_cyc_r)/i);
163 }
164
165 tot_cyc_n = 0;
166 tot_cyc_r = 0;
167
168 printf("Validating division by power of 2.\n");
169 for (i = 0; i < 64; i++) {
170 divisor_u64 = 1ull << i;
171 reci_u64 = rte_reciprocal_value_u64(divisor_u64);
172
173 dividend_u64 = rte_rand();
174
175 start_cyc = rte_rdtsc();
176 nresult_u64 = dividend_u64 / divisor_u64;
177 split_cyc = rte_rdtsc();
178 rresult_u64 = rte_reciprocal_divide_u64(dividend_u64,
179 &reci_u64);
180 end_cyc = rte_rdtsc();
181
182 tot_cyc_n += split_cyc - start_cyc;
183 tot_cyc_r += end_cyc - split_cyc;
184 if (nresult_u64 != rresult_u64) {
185 printf("Division 64 failed, %"PRIu64"/%"PRIu64" = "
186 "expected %"PRIu64" result %"PRIu64"\n",
187 dividend_u64, divisor_u64,
188 nresult_u64, rresult_u64);
189 result = 1;
190 break;
191 }
192 }
193 printf("64bit Division results:\n");
194 printf("Total number of cycles normal division : %"PRIu64"\n",
195 tot_cyc_n);
196 printf("Total number of cycles reciprocal division : %"PRIu64"\n",
197 tot_cyc_r);
198 if (i != 0) {
199 printf("Cycles per division(normal) : %3.2f\n",
200 ((double)tot_cyc_n)/i);
201 printf("Cycles per division(reciprocal) : %3.2f\n",
202 ((double)tot_cyc_r)/i);
203 }
204
205 return result;
206 }
207
208 REGISTER_TEST_COMMAND(reciprocal_division_perf, test_reciprocal_division_perf);
209