xref: /linux/net/sunrpc/xprtrdma/svc_rdma.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright (c) 2015-2018 Oracle.  All rights reserved.
4  * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the BSD-type
10  * license below:
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  *
16  *      Redistributions of source code must retain the above copyright
17  *      notice, this list of conditions and the following disclaimer.
18  *
19  *      Redistributions in binary form must reproduce the above
20  *      copyright notice, this list of conditions and the following
21  *      disclaimer in the documentation and/or other materials provided
22  *      with the distribution.
23  *
24  *      Neither the name of the Network Appliance, Inc. nor the names of
25  *      its contributors may be used to endorse or promote products
26  *      derived from this software without specific prior written
27  *      permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40  *
41  * Author: Tom Tucker <tom@opengridcomputing.com>
42  */
43 
44 #include <linux/slab.h>
45 #include <linux/fs.h>
46 #include <linux/sysctl.h>
47 #include <linux/workqueue.h>
48 #include <linux/sunrpc/clnt.h>
49 #include <linux/sunrpc/sched.h>
50 #include <linux/sunrpc/svc_rdma.h>
51 
52 #define RPCDBG_FACILITY	RPCDBG_SVCXPRT
53 
54 /* RPC/RDMA parameters */
55 unsigned int svcrdma_ord = 16;	/* historical default */
56 static unsigned int min_ord = 1;
57 static unsigned int max_ord = 255;
58 unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
59 unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS;
60 static unsigned int min_max_requests = 4;
61 static unsigned int max_max_requests = 16384;
62 unsigned int svcrdma_max_req_size = RPCRDMA_DEF_INLINE_THRESH;
63 static unsigned int min_max_inline = RPCRDMA_DEF_INLINE_THRESH;
64 static unsigned int max_max_inline = RPCRDMA_MAX_INLINE_THRESH;
65 static unsigned int svcrdma_stat_unused;
66 static unsigned int zero;
67 
68 struct percpu_counter svcrdma_stat_read;
69 struct percpu_counter svcrdma_stat_recv;
70 struct percpu_counter svcrdma_stat_sq_starve;
71 struct percpu_counter svcrdma_stat_write;
72 
73 enum {
74 	SVCRDMA_COUNTER_BUFSIZ	= sizeof(unsigned long long),
75 };
76 
77 static int svcrdma_counter_handler(const struct ctl_table *table, int write,
78 				   void *buffer, size_t *lenp, loff_t *ppos)
79 {
80 	struct percpu_counter *stat = (struct percpu_counter *)table->data;
81 	char tmp[SVCRDMA_COUNTER_BUFSIZ + 1];
82 	int len;
83 
84 	if (write) {
85 		percpu_counter_set(stat, 0);
86 		return 0;
87 	}
88 
89 	len = snprintf(tmp, SVCRDMA_COUNTER_BUFSIZ, "%lld\n",
90 		       percpu_counter_sum_positive(stat));
91 	if (len >= SVCRDMA_COUNTER_BUFSIZ)
92 		return -EFAULT;
93 	len = strlen(tmp);
94 	if (*ppos > len) {
95 		*lenp = 0;
96 		return 0;
97 	}
98 	len -= *ppos;
99 	if (len > *lenp)
100 		len = *lenp;
101 	if (len)
102 		memcpy(buffer, tmp, len);
103 	*lenp = len;
104 	*ppos += len;
105 
106 	return 0;
107 }
108 
109 static struct ctl_table_header *svcrdma_table_header;
110 static struct ctl_table svcrdma_parm_table[] = {
111 	{
112 		.procname	= "max_requests",
113 		.data		= &svcrdma_max_requests,
114 		.maxlen		= sizeof(unsigned int),
115 		.mode		= 0644,
116 		.proc_handler	= proc_dointvec_minmax,
117 		.extra1		= &min_max_requests,
118 		.extra2		= &max_max_requests
119 	},
120 	{
121 		.procname	= "max_req_size",
122 		.data		= &svcrdma_max_req_size,
123 		.maxlen		= sizeof(unsigned int),
124 		.mode		= 0644,
125 		.proc_handler	= proc_dointvec_minmax,
126 		.extra1		= &min_max_inline,
127 		.extra2		= &max_max_inline
128 	},
129 	{
130 		.procname	= "max_outbound_read_requests",
131 		.data		= &svcrdma_ord,
132 		.maxlen		= sizeof(unsigned int),
133 		.mode		= 0644,
134 		.proc_handler	= proc_dointvec_minmax,
135 		.extra1		= &min_ord,
136 		.extra2		= &max_ord,
137 	},
138 
139 	{
140 		.procname	= "rdma_stat_read",
141 		.data		= &svcrdma_stat_read,
142 		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
143 		.mode		= 0644,
144 		.proc_handler	= svcrdma_counter_handler,
145 	},
146 	{
147 		.procname	= "rdma_stat_recv",
148 		.data		= &svcrdma_stat_recv,
149 		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
150 		.mode		= 0644,
151 		.proc_handler	= svcrdma_counter_handler,
152 	},
153 	{
154 		.procname	= "rdma_stat_write",
155 		.data		= &svcrdma_stat_write,
156 		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
157 		.mode		= 0644,
158 		.proc_handler	= svcrdma_counter_handler,
159 	},
160 	{
161 		.procname	= "rdma_stat_sq_starve",
162 		.data		= &svcrdma_stat_sq_starve,
163 		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
164 		.mode		= 0644,
165 		.proc_handler	= svcrdma_counter_handler,
166 	},
167 	{
168 		.procname	= "rdma_stat_rq_starve",
169 		.data		= &svcrdma_stat_unused,
170 		.maxlen		= sizeof(unsigned int),
171 		.mode		= 0644,
172 		.proc_handler	= proc_dointvec_minmax,
173 		.extra1		= &zero,
174 		.extra2		= &zero,
175 	},
176 	{
177 		.procname	= "rdma_stat_rq_poll",
178 		.data		= &svcrdma_stat_unused,
179 		.maxlen		= sizeof(unsigned int),
180 		.mode		= 0644,
181 		.proc_handler	= proc_dointvec_minmax,
182 		.extra1		= &zero,
183 		.extra2		= &zero,
184 	},
185 	{
186 		.procname	= "rdma_stat_rq_prod",
187 		.data		= &svcrdma_stat_unused,
188 		.maxlen		= sizeof(unsigned int),
189 		.mode		= 0644,
190 		.proc_handler	= proc_dointvec_minmax,
191 		.extra1		= &zero,
192 		.extra2		= &zero,
193 	},
194 	{
195 		.procname	= "rdma_stat_sq_poll",
196 		.data		= &svcrdma_stat_unused,
197 		.maxlen		= sizeof(unsigned int),
198 		.mode		= 0644,
199 		.proc_handler	= proc_dointvec_minmax,
200 		.extra1		= &zero,
201 		.extra2		= &zero,
202 	},
203 	{
204 		.procname	= "rdma_stat_sq_prod",
205 		.data		= &svcrdma_stat_unused,
206 		.maxlen		= sizeof(unsigned int),
207 		.mode		= 0644,
208 		.proc_handler	= proc_dointvec_minmax,
209 		.extra1		= &zero,
210 		.extra2		= &zero,
211 	},
212 };
213 
214 static void svc_rdma_proc_cleanup(void)
215 {
216 	if (!svcrdma_table_header)
217 		return;
218 	unregister_sysctl_table(svcrdma_table_header);
219 	svcrdma_table_header = NULL;
220 
221 	percpu_counter_destroy(&svcrdma_stat_write);
222 	percpu_counter_destroy(&svcrdma_stat_sq_starve);
223 	percpu_counter_destroy(&svcrdma_stat_recv);
224 	percpu_counter_destroy(&svcrdma_stat_read);
225 }
226 
227 static int svc_rdma_proc_init(void)
228 {
229 	int rc;
230 
231 	if (svcrdma_table_header)
232 		return 0;
233 
234 	rc = percpu_counter_init(&svcrdma_stat_read, 0, GFP_KERNEL);
235 	if (rc)
236 		goto err;
237 	rc = percpu_counter_init(&svcrdma_stat_recv, 0, GFP_KERNEL);
238 	if (rc)
239 		goto err_read;
240 	rc = percpu_counter_init(&svcrdma_stat_sq_starve, 0, GFP_KERNEL);
241 	if (rc)
242 		goto err_recv;
243 	rc = percpu_counter_init(&svcrdma_stat_write, 0, GFP_KERNEL);
244 	if (rc)
245 		goto err_sq;
246 
247 	svcrdma_table_header = register_sysctl("sunrpc/svc_rdma",
248 					       svcrdma_parm_table);
249 	if (!svcrdma_table_header)
250 		goto err_write;
251 
252 	return 0;
253 
254 err_write:
255 	rc = -ENOMEM;
256 	percpu_counter_destroy(&svcrdma_stat_write);
257 err_sq:
258 	percpu_counter_destroy(&svcrdma_stat_sq_starve);
259 err_recv:
260 	percpu_counter_destroy(&svcrdma_stat_recv);
261 err_read:
262 	percpu_counter_destroy(&svcrdma_stat_read);
263 err:
264 	return rc;
265 }
266 
267 struct workqueue_struct *svcrdma_wq;
268 
269 void svc_rdma_cleanup(void)
270 {
271 	svc_unreg_xprt_class(&svc_rdma_class);
272 	svc_rdma_proc_cleanup();
273 	if (svcrdma_wq) {
274 		struct workqueue_struct *wq = svcrdma_wq;
275 
276 		svcrdma_wq = NULL;
277 		destroy_workqueue(wq);
278 	}
279 
280 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
281 }
282 
283 int svc_rdma_init(void)
284 {
285 	struct workqueue_struct *wq;
286 	int rc;
287 
288 	wq = alloc_workqueue("svcrdma", WQ_UNBOUND, 0);
289 	if (!wq)
290 		return -ENOMEM;
291 
292 	rc = svc_rdma_proc_init();
293 	if (rc) {
294 		destroy_workqueue(wq);
295 		return rc;
296 	}
297 
298 	svcrdma_wq = wq;
299 	svc_reg_xprt_class(&svc_rdma_class);
300 
301 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
302 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
303 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
304 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
305 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
306 	return 0;
307 }
308