xref: /freebsd/sys/dev/ena/ena_rss.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2015-2021 Amazon.com, Inc. or its affiliates.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_rss.h"
36 
37 #include "ena_rss.h"
38 
39 /*
40  * This function should generate unique key for the whole driver.
41  * If the key was already genereated in the previous call (for example
42  * for another adapter), then it should be returned instead.
43  */
44 void
45 ena_rss_key_fill(void *key, size_t size)
46 {
47 	static bool key_generated;
48 	static uint8_t default_key[ENA_HASH_KEY_SIZE];
49 
50 	KASSERT(size <= ENA_HASH_KEY_SIZE,
51 	    ("Requested more bytes than ENA RSS key can hold"));
52 
53 	if (!key_generated) {
54 		arc4random_buf(default_key, ENA_HASH_KEY_SIZE);
55 		key_generated = true;
56 	}
57 
58 	memcpy(key, default_key, size);
59 }
60 
61 /*
62  * ENA HW expects the key to be in reverse-byte order.
63  */
64 static void
65 ena_rss_reorder_hash_key(u8 *reordered_key, const u8 *key, size_t key_size)
66 {
67 	int i;
68 
69 	key = key + key_size - 1;
70 
71 	for (i = 0; i < key_size; ++i)
72 		*reordered_key++ = *key--;
73 }
74 
75 int
76 ena_rss_set_hash(struct ena_com_dev *ena_dev, const u8 *key)
77 {
78 	enum ena_admin_hash_functions ena_func = ENA_ADMIN_TOEPLITZ;
79 	u8 hw_key[ENA_HASH_KEY_SIZE];
80 
81 	ena_rss_reorder_hash_key(hw_key, key, ENA_HASH_KEY_SIZE);
82 
83 	return (ena_com_fill_hash_function(ena_dev, ena_func, hw_key,
84 	    ENA_HASH_KEY_SIZE, 0x0));
85 }
86 
87 int
88 ena_rss_get_hash_key(struct ena_com_dev *ena_dev, u8 *key)
89 {
90 	u8 hw_key[ENA_HASH_KEY_SIZE];
91 	int rc;
92 
93 	rc = ena_com_get_hash_key(ena_dev, hw_key);
94 	if (rc != 0)
95 		return rc;
96 
97 	ena_rss_reorder_hash_key(key, hw_key, ENA_HASH_KEY_SIZE);
98 
99 	return (0);
100 }
101 
102 static int
103 ena_rss_init_default(struct ena_adapter *adapter)
104 {
105 	struct ena_com_dev *ena_dev = adapter->ena_dev;
106 	device_t dev = adapter->pdev;
107 	int qid, rc, i;
108 
109 	rc = ena_com_rss_init(ena_dev, ENA_RX_RSS_TABLE_LOG_SIZE);
110 	if (unlikely(rc != 0)) {
111 		ena_log(dev, ERR, "Cannot init indirect table\n");
112 		return (rc);
113 	}
114 
115 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; i++) {
116 #ifdef RSS
117 		qid = rss_get_indirection_to_bucket(i) % adapter->num_io_queues;
118 #else
119 		qid = i % adapter->num_io_queues;
120 #endif
121 		rc = ena_com_indirect_table_fill_entry(ena_dev, i,
122 		    ENA_IO_RXQ_IDX(qid));
123 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
124 			ena_log(dev, ERR, "Cannot fill indirect table\n");
125 			goto err_rss_destroy;
126 		}
127 	}
128 
129 
130 #ifdef RSS
131 	uint8_t rss_algo = rss_gethashalgo();
132 	if (rss_algo == RSS_HASH_TOEPLITZ) {
133 		uint8_t hash_key[RSS_KEYSIZE];
134 
135 		rss_getkey(hash_key);
136 		rc = ena_rss_set_hash(ena_dev, hash_key);
137 	} else
138 #endif
139 		rc = ena_com_fill_hash_function(ena_dev, ENA_ADMIN_TOEPLITZ,
140 		    NULL, ENA_HASH_KEY_SIZE, 0x0);
141 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
142 		ena_log(dev, ERR, "Cannot fill hash function\n");
143 		goto err_rss_destroy;
144 	}
145 
146 	rc = ena_com_set_default_hash_ctrl(ena_dev);
147 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
148 		ena_log(dev, ERR, "Cannot fill hash control\n");
149 		goto err_rss_destroy;
150 	}
151 
152 	rc = ena_rss_indir_init(adapter);
153 
154 	return (rc == EOPNOTSUPP ? 0 : rc);
155 
156 err_rss_destroy:
157 	ena_com_rss_destroy(ena_dev);
158 	return (rc);
159 }
160 
161 /* Configure the Rx forwarding */
162 int
163 ena_rss_configure(struct ena_adapter *adapter)
164 {
165 	struct ena_com_dev *ena_dev = adapter->ena_dev;
166 	int rc;
167 
168 	/* In case the RSS table was destroyed */
169 	if (!ena_dev->rss.tbl_log_size) {
170 		rc = ena_rss_init_default(adapter);
171 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
172 			ena_log(adapter->pdev, ERR,
173 			    "WARNING: RSS was not properly re-initialized,"
174 			    " it will affect bandwidth\n");
175 			ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
176 			return (rc);
177 		}
178 	}
179 
180 	/* Set indirect table */
181 	rc = ena_com_indirect_table_set(ena_dev);
182 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
183 		return (rc);
184 
185 	/* Configure hash function (if supported) */
186 	rc = ena_com_set_hash_function(ena_dev);
187 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
188 		return (rc);
189 
190 	/* Configure hash inputs (if supported) */
191 	rc = ena_com_set_hash_ctrl(ena_dev);
192 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
193 		return (rc);
194 
195 	return (0);
196 }
197 
198 static void
199 ena_rss_init_default_deferred(void *arg)
200 {
201 	struct ena_adapter *adapter;
202 	devclass_t dc;
203 	int max;
204 	int rc;
205 
206 	dc = devclass_find("ena");
207 	if (unlikely(dc == NULL)) {
208 		ena_log_raw(ERR, "SYSINIT: %s: No devclass ena\n", __func__);
209 		return;
210 	}
211 
212 	max = devclass_get_maxunit(dc);
213 	while (max-- >= 0) {
214 		adapter = devclass_get_softc(dc, max);
215 		if (adapter != NULL) {
216 			rc = ena_rss_init_default(adapter);
217 			ENA_FLAG_SET_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
218 			if (unlikely(rc != 0)) {
219 				ena_log(adapter->pdev, WARN,
220 				    "WARNING: RSS was not properly initialized,"
221 				    " it will affect bandwidth\n");
222 				ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE,
223 				    adapter);
224 			}
225 		}
226 	}
227 }
228 SYSINIT(ena_rss_init, SI_SUB_KICK_SCHEDULER, SI_ORDER_SECOND,
229     ena_rss_init_default_deferred, NULL);
230 
231 int
232 ena_rss_indir_get(struct ena_adapter *adapter, uint32_t *table)
233 {
234 	int rc, i;
235 
236 	rc = ena_com_indirect_table_get(adapter->ena_dev, table);
237 	if (rc != 0) {
238 		if (rc == EOPNOTSUPP)
239 			device_printf(adapter->pdev,
240 			    "Reading from indirection table not supported\n");
241 		else
242 			device_printf(adapter->pdev,
243 			    "Unable to get indirection table\n");
244 		return (rc);
245 	}
246 
247 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i)
248 		table[i] = ENA_IO_RXQ_IDX_TO_COMBINED_IDX(table[i]);
249 
250 	return (0);
251 }
252 
253 int
254 ena_rss_indir_set(struct ena_adapter *adapter, uint32_t *table)
255 {
256 	int rc, i;
257 
258 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i) {
259 		rc = ena_com_indirect_table_fill_entry(adapter->ena_dev, i,
260 		    ENA_IO_RXQ_IDX(table[i]));
261 		if (rc != 0) {
262 			device_printf(adapter->pdev,
263 			    "Cannot fill indirection table entry %d\n", i);
264 			return (rc);
265 		}
266 	}
267 
268 	rc = ena_com_indirect_table_set(adapter->ena_dev);
269 	if (rc == EOPNOTSUPP)
270 		device_printf(adapter->pdev,
271 		    "Writing to indirection table not supported\n");
272 	else if (rc != 0)
273 		device_printf(adapter->pdev, "Cannot set indirection table\n");
274 
275 	return (rc);
276 }
277 
278 int
279 ena_rss_indir_init(struct ena_adapter *adapter)
280 {
281 	struct ena_indir *indir = adapter->rss_indir;
282 	int rc;
283 
284 	if (indir == NULL) {
285 		adapter->rss_indir = indir = malloc(sizeof(struct ena_indir),
286 		    M_DEVBUF, M_WAITOK | M_ZERO);
287 		if (indir == NULL)
288 			return (ENOMEM);
289 	}
290 
291 	rc = ena_rss_indir_get(adapter, indir->table);
292 	if (rc != 0) {
293 		free(adapter->rss_indir, M_DEVBUF);
294 		adapter->rss_indir = NULL;
295 
296 		return (rc);
297 	}
298 
299 	ena_rss_copy_indir_buf(indir->sysctl_buf, indir->table);
300 
301 	return (0);
302 }
303