xref: /freebsd/sys/dev/ena/ena_rss.c (revision 96cde0b9e6068cd4c3aaebd86764b34afec1b624)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2015-2024 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 #include "opt_rss.h"
34 
35 #include "ena_rss.h"
36 
37 /*
38  * This function should generate unique key for the whole driver.
39  * If the key was already genereated in the previous call (for example
40  * for another adapter), then it should be returned instead.
41  */
42 void
ena_rss_key_fill(void * key,size_t size)43 ena_rss_key_fill(void *key, size_t size)
44 {
45 	static bool key_generated;
46 	static uint8_t default_key[ENA_HASH_KEY_SIZE];
47 
48 	KASSERT(size <= ENA_HASH_KEY_SIZE,
49 	    ("Requested more bytes than ENA RSS key can hold"));
50 
51 	if (!key_generated) {
52 		arc4random_buf(default_key, ENA_HASH_KEY_SIZE);
53 		key_generated = true;
54 	}
55 
56 	memcpy(key, default_key, size);
57 }
58 
59 /*
60  * ENA HW expects the key to be in reverse-byte order.
61  */
62 static void
ena_rss_reorder_hash_key(u8 * reordered_key,const u8 * key,size_t key_size)63 ena_rss_reorder_hash_key(u8 *reordered_key, const u8 *key, size_t key_size)
64 {
65 	int i;
66 
67 	key = key + key_size - 1;
68 
69 	for (i = 0; i < key_size; ++i)
70 		*reordered_key++ = *key--;
71 }
72 
73 int
ena_rss_set_hash(struct ena_com_dev * ena_dev,const u8 * key)74 ena_rss_set_hash(struct ena_com_dev *ena_dev, const u8 *key)
75 {
76 	enum ena_admin_hash_functions ena_func = ENA_ADMIN_TOEPLITZ;
77 	u8 hw_key[ENA_HASH_KEY_SIZE];
78 
79 	ena_rss_reorder_hash_key(hw_key, key, ENA_HASH_KEY_SIZE);
80 
81 	return (ena_com_fill_hash_function(ena_dev, ena_func, hw_key,
82 	    ENA_HASH_KEY_SIZE, 0x0));
83 }
84 
85 int
ena_rss_get_hash_key(struct ena_com_dev * ena_dev,u8 * key)86 ena_rss_get_hash_key(struct ena_com_dev *ena_dev, u8 *key)
87 {
88 	u8 hw_key[ENA_HASH_KEY_SIZE];
89 	int rc;
90 
91 	rc = ena_com_get_hash_key(ena_dev, hw_key);
92 	if (rc != 0)
93 		return rc;
94 
95 	ena_rss_reorder_hash_key(key, hw_key, ENA_HASH_KEY_SIZE);
96 
97 	return (0);
98 }
99 
100 static int
ena_rss_init_default(struct ena_adapter * adapter)101 ena_rss_init_default(struct ena_adapter *adapter)
102 {
103 	struct ena_com_dev *ena_dev = adapter->ena_dev;
104 	device_t dev = adapter->pdev;
105 	int qid, rc, i;
106 
107 	rc = ena_com_rss_init(ena_dev, ENA_RX_RSS_TABLE_LOG_SIZE);
108 	if (unlikely(rc != 0)) {
109 		ena_log(dev, ERR, "Cannot init indirect table\n");
110 		return (rc);
111 	}
112 
113 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; i++) {
114 #ifdef RSS
115 		qid = rss_get_indirection_to_bucket(i) % adapter->num_io_queues;
116 #else
117 		qid = i % adapter->num_io_queues;
118 #endif
119 		rc = ena_com_indirect_table_fill_entry(ena_dev, i,
120 		    ENA_IO_RXQ_IDX(qid));
121 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
122 			ena_log(dev, ERR, "Cannot fill indirect table\n");
123 			goto err_rss_destroy;
124 		}
125 	}
126 
127 
128 	uint8_t rss_algo = rss_gethashalgo();
129 	if (rss_algo == RSS_HASH_TOEPLITZ) {
130 		uint8_t hash_key[RSS_KEYSIZE];
131 
132 		rss_getkey(hash_key);
133 		rc = ena_rss_set_hash(ena_dev, hash_key);
134 	} else
135 		rc = ena_com_fill_hash_function(ena_dev, ENA_ADMIN_TOEPLITZ,
136 		    NULL, ENA_HASH_KEY_SIZE, 0x0);
137 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
138 		ena_log(dev, ERR, "Cannot fill hash function\n");
139 		goto err_rss_destroy;
140 	}
141 
142 	rc = ena_com_set_default_hash_ctrl(ena_dev);
143 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
144 		ena_log(dev, ERR, "Cannot fill hash control\n");
145 		goto err_rss_destroy;
146 	}
147 
148 	rc = ena_rss_indir_init(adapter);
149 
150 	return (rc == EOPNOTSUPP ? 0 : rc);
151 
152 err_rss_destroy:
153 	ena_com_rss_destroy(ena_dev);
154 	return (rc);
155 }
156 
157 /* Configure the Rx forwarding */
158 int
ena_rss_configure(struct ena_adapter * adapter)159 ena_rss_configure(struct ena_adapter *adapter)
160 {
161 	struct ena_com_dev *ena_dev = adapter->ena_dev;
162 	int rc;
163 
164 	/* In case the RSS table was destroyed */
165 	if (!ena_dev->rss.tbl_log_size) {
166 		rc = ena_rss_init_default(adapter);
167 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
168 			ena_log(adapter->pdev, ERR,
169 			    "WARNING: RSS was not properly re-initialized,"
170 			    " it will affect bandwidth\n");
171 			ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
172 			return (rc);
173 		}
174 	}
175 
176 	/* Set indirect table */
177 	rc = ena_com_indirect_table_set(ena_dev);
178 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
179 		return (rc);
180 
181 	/* Configure hash function (if supported) */
182 	rc = ena_com_set_hash_function(ena_dev);
183 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
184 		return (rc);
185 
186 	/* Configure hash inputs (if supported) */
187 	rc = ena_com_set_hash_ctrl(ena_dev);
188 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
189 		return (rc);
190 
191 	return (0);
192 }
193 
194 static void
ena_rss_init_default_deferred(void * arg)195 ena_rss_init_default_deferred(void *arg)
196 {
197 	struct ena_adapter *adapter;
198 	devclass_t dc;
199 	int max;
200 	int rc;
201 
202 	dc = devclass_find("ena");
203 	if (unlikely(dc == NULL)) {
204 		ena_log_raw(ERR, "SYSINIT: %s: No devclass ena\n", __func__);
205 		return;
206 	}
207 
208 	max = devclass_get_maxunit(dc);
209 	while (max-- >= 0) {
210 		adapter = devclass_get_softc(dc, max);
211 		if (adapter != NULL) {
212 			rc = ena_rss_init_default(adapter);
213 			ENA_FLAG_SET_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
214 			if (unlikely(rc != 0)) {
215 				ena_log(adapter->pdev, WARN,
216 				    "WARNING: RSS was not properly initialized,"
217 				    " it will affect bandwidth\n");
218 				ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE,
219 				    adapter);
220 			}
221 		}
222 	}
223 }
224 SYSINIT(ena_rss_init, SI_SUB_KICK_SCHEDULER, SI_ORDER_SECOND,
225     ena_rss_init_default_deferred, NULL);
226 
227 int
ena_rss_indir_get(struct ena_adapter * adapter,uint32_t * table)228 ena_rss_indir_get(struct ena_adapter *adapter, uint32_t *table)
229 {
230 	int rc, i;
231 
232 	rc = ena_com_indirect_table_get(adapter->ena_dev, table);
233 	if (rc != 0) {
234 		if (rc == EOPNOTSUPP)
235 			device_printf(adapter->pdev,
236 			    "Reading from indirection table not supported\n");
237 		else
238 			device_printf(adapter->pdev,
239 			    "Unable to get indirection table\n");
240 		return (rc);
241 	}
242 
243 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i)
244 		table[i] = ENA_IO_RXQ_IDX_TO_COMBINED_IDX(table[i]);
245 
246 	return (0);
247 }
248 
249 int
ena_rss_indir_set(struct ena_adapter * adapter,uint32_t * table)250 ena_rss_indir_set(struct ena_adapter *adapter, uint32_t *table)
251 {
252 	int rc, i;
253 
254 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i) {
255 		rc = ena_com_indirect_table_fill_entry(adapter->ena_dev, i,
256 		    ENA_IO_RXQ_IDX(table[i]));
257 		if (rc != 0) {
258 			device_printf(adapter->pdev,
259 			    "Cannot fill indirection table entry %d\n", i);
260 			return (rc);
261 		}
262 	}
263 
264 	rc = ena_com_indirect_table_set(adapter->ena_dev);
265 	if (rc == EOPNOTSUPP)
266 		device_printf(adapter->pdev,
267 		    "Writing to indirection table not supported\n");
268 	else if (rc != 0)
269 		device_printf(adapter->pdev, "Cannot set indirection table\n");
270 
271 	return (rc);
272 }
273 
274 int
ena_rss_indir_init(struct ena_adapter * adapter)275 ena_rss_indir_init(struct ena_adapter *adapter)
276 {
277 	struct ena_indir *indir = adapter->rss_indir;
278 	int rc;
279 
280 	if (indir == NULL)
281 		adapter->rss_indir = indir = malloc(sizeof(struct ena_indir),
282 		    M_DEVBUF, M_WAITOK | M_ZERO);
283 
284 	rc = ena_rss_indir_get(adapter, indir->table);
285 	if (rc != 0) {
286 		free(adapter->rss_indir, M_DEVBUF);
287 		adapter->rss_indir = NULL;
288 
289 		return (rc);
290 	}
291 
292 	ena_rss_copy_indir_buf(indir->sysctl_buf, indir->table);
293 
294 	return (0);
295 }
296