1 /*-
2 * Copyright 2016-2021 Microchip Technology, Inc. and/or its subsidiaries.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26 /* $FreeBSD$ */
27
28 #include "smartpqi_includes.h"
29
30 #ifndef LOCKFREE_STACK
31
32 /*
33 * Function used to release the tag from taglist.
34 */
35 void
36 pqisrc_put_tag(pqi_taglist_t *taglist, uint32_t elem)
37 {
38
39 OS_ACQUIRE_SPINLOCK(&(taglist->lock));
40 DBG_FUNC("IN\n");
41
42 ASSERT(taglist->num_elem < taglist->max_elem);
43
44 if (taglist->num_elem < taglist->max_elem) {
45 taglist->elem_array[taglist->tail] = elem;
46 taglist->num_elem++;
47 taglist->tail = (taglist->tail + 1) % taglist->max_elem;
48 }
49
50 OS_RELEASE_SPINLOCK(&taglist->lock);
51
52 DBG_FUNC("OUT\n");
53 }
54
55 /*
56 * Function used to get an unoccupied tag from the tag list.
57 */
58 uint32_t
59 pqisrc_get_tag(pqi_taglist_t *taglist)
60 {
61 uint32_t elem = INVALID_ELEM;
62
63 /* DBG_FUNC("IN\n");*/
64
65 OS_ACQUIRE_SPINLOCK(&taglist->lock);
66
67 ASSERT(taglist->num_elem > 0);
68
69 if (taglist->num_elem > 0) {
70 elem = taglist->elem_array[taglist->head];
71 taglist->num_elem--;
72 taglist->head = (taglist->head + 1) % taglist->max_elem;
73 }
74
75 OS_RELEASE_SPINLOCK(&taglist->lock);
76
77 /* DBG_FUNC("OUT got %d\n", elem);*/
78 return elem;
79 }
80
81 /*
82 * Initialize circular queue implementation of tag list.
83 */
84 int
85 pqisrc_init_taglist(pqisrc_softstate_t *softs, pqi_taglist_t *taglist,
86 uint32_t max_elem)
87 {
88 int ret = PQI_STATUS_SUCCESS;
89 int i = 0;
90
91 DBG_FUNC("IN\n");
92
93 taglist->max_elem = max_elem;
94 taglist->num_elem = 0;
95 taglist->head = 0;
96 taglist->tail = 0;
97 taglist->elem_array = os_mem_alloc(softs,
98 (max_elem * sizeof(uint32_t)));
99 if (!(taglist->elem_array)) {
100 DBG_FUNC("Unable to allocate memory for taglist\n");
101 ret = PQI_STATUS_FAILURE;
102 goto err_out;
103 }
104
105 os_strlcpy(taglist->lockname, "tag_lock", LOCKNAME_SIZE);
106 ret = os_init_spinlock(softs, &taglist->lock, taglist->lockname);
107 if(ret){
108 DBG_ERR("tag lock initialization failed\n");
109 taglist->lockcreated=false;
110 goto err_lock;
111 }
112 taglist->lockcreated = true;
113
114 /* indices 1 to max_elem are considered as valid tags */
115 for (i=1; i <= max_elem; i++) {
116 softs->rcb[i].tag = INVALID_ELEM;
117 pqisrc_put_tag(taglist, i);
118 }
119
120 DBG_FUNC("OUT\n");
121 return ret;
122
123 err_lock:
124 os_mem_free(softs, (char *)taglist->elem_array,
125 (taglist->max_elem * sizeof(uint32_t)));
126 taglist->elem_array = NULL;
127 err_out:
128 DBG_FUNC("OUT failed\n");
129 return ret;
130 }
131
132 /*
133 * Destroy circular queue implementation of tag list.
134 */
135 void
136 pqisrc_destroy_taglist(pqisrc_softstate_t *softs, pqi_taglist_t *taglist)
137 {
138 DBG_FUNC("IN\n");
139 os_mem_free(softs, (char *)taglist->elem_array,
140 (taglist->max_elem * sizeof(uint32_t)));
141 taglist->elem_array = NULL;
142
143 if(taglist->lockcreated==true){
144 os_uninit_spinlock(&taglist->lock);
145 taglist->lockcreated = false;
146 }
147
148 DBG_FUNC("OUT\n");
149 }
150
151 #else /* LOCKFREE_STACK */
152
153 /*
154 * Initialize circular queue implementation of tag list.
155 */
156 int
157 pqisrc_init_taglist(pqisrc_softstate_t *softs, lockless_stack_t *stack,
158 uint32_t max_elem)
159 {
160 int ret = PQI_STATUS_SUCCESS;
161 int index = 0;
162
163 DBG_FUNC("IN\n");
164
165 /* indices 1 to max_elem are considered as valid tags */
166 stack->max_elem = max_elem + 1;
167 stack->head.data = 0;
168 DBG_INFO("Stack head address :%p\n",&stack->head);
169
170 /*Allocate memory for stack*/
171 stack->next_index_array = (uint32_t*)os_mem_alloc(softs,
172 (stack->max_elem * sizeof(uint32_t)));
173 if (!(stack->next_index_array)) {
174 DBG_ERR("Unable to allocate memory for stack\n");
175 ret = PQI_STATUS_FAILURE;
176 goto err_out;
177 }
178
179 /* push all the entries to the stack */
180 for (index = 1; index < stack->max_elem ; index++) {
181 softs->rcb[index].tag = INVALID_ELEM;
182 pqisrc_put_tag(stack, index);
183 }
184
185 DBG_FUNC("OUT\n");
186 return ret;
187 err_out:
188 DBG_FUNC("Failed OUT\n");
189 return ret;
190 }
191
192 /*
193 * Destroy circular queue implementation of tag list.
194 */
195 void
196 pqisrc_destroy_taglist(pqisrc_softstate_t *softs, lockless_stack_t *stack)
197 {
198 DBG_FUNC("IN\n");
199
200 /* de-allocate stack memory */
201 if (stack->next_index_array) {
202 os_mem_free(softs,(char*)stack->next_index_array,
203 (stack->max_elem * sizeof(uint32_t)));
204 stack->next_index_array = NULL;
205 }
206
207 DBG_FUNC("OUT\n");
208 }
209
210 /*
211 * Function used to release the tag from taglist.
212 */
213 void
214 pqisrc_put_tag(lockless_stack_t *stack, uint32_t index)
215 {
216 union head_list cur_head, new_head;
217
218 DBG_FUNC("IN\n");
219 DBG_INFO("push tag :%d\n",index);
220
221 if (index >= stack->max_elem) {
222 ASSERT(false);
223 DBG_INFO("Pushed Invalid index\n"); /* stack full */
224 return;
225 }
226
227 if (stack->next_index_array[index] != 0) {
228 ASSERT(false);
229 DBG_INFO("Index already present as tag in the stack\n");
230 return;
231 }
232
233 do {
234 cur_head = stack->head;
235 /* increment seq_no */
236 new_head.top.seq_no = cur_head.top.seq_no + 1;
237 /* update the index at the top of the stack with the new index */
238 new_head.top.index = index;
239 /* Create a link to the previous index */
240 stack->next_index_array[index] = cur_head.top.index;
241 }while(!os_atomic64_cas(&stack->head.data,cur_head.data,new_head.data));
242 stack->num_elem++;
243 DBG_FUNC("OUT\n");
244 return;
245 }
246
247 /*
248 * Function used to get an unoccupied tag from the tag list.
249 */
250 uint32_t
251 pqisrc_get_tag(lockless_stack_t *stack)
252 {
253 union head_list cur_head, new_head;
254
255 DBG_FUNC("IN\n");
256 do {
257 cur_head = stack->head;
258 if (cur_head.top.index == 0) /* stack empty */
259 return INVALID_ELEM;
260 /* increment seq_no field */
261 new_head.top.seq_no = cur_head.top.seq_no + 1;
262 /* update the index at the top of the stack with the next index */
263 new_head.top.index = stack->next_index_array[cur_head.top.index];
264 }while(!os_atomic64_cas(&stack->head.data,cur_head.data,new_head.data));
265 stack->next_index_array[cur_head.top.index] = 0;
266 stack->num_elem--;
267
268 DBG_INFO("pop tag: %d\n",cur_head.top.index);
269 DBG_FUNC("OUT\n");
270 return cur_head.top.index; /*tag*/
271 }
272 #endif /* LOCKFREE_STACK */
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