xref: /linux/net/sunrpc/xprtrdma/svc_rdma.c (revision 18f90d372cf35b387663f1567de701e5393f6eb5)
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 
66 atomic_t rdma_stat_recv;
67 atomic_t rdma_stat_read;
68 atomic_t rdma_stat_write;
69 atomic_t rdma_stat_sq_starve;
70 atomic_t rdma_stat_rq_starve;
71 atomic_t rdma_stat_rq_poll;
72 atomic_t rdma_stat_rq_prod;
73 atomic_t rdma_stat_sq_poll;
74 atomic_t rdma_stat_sq_prod;
75 
76 struct workqueue_struct *svc_rdma_wq;
77 
78 /*
79  * This function implements reading and resetting an atomic_t stat
80  * variable through read/write to a proc file. Any write to the file
81  * resets the associated statistic to zero. Any read returns it's
82  * current value.
83  */
84 static int read_reset_stat(struct ctl_table *table, int write,
85 			   void __user *buffer, size_t *lenp,
86 			   loff_t *ppos)
87 {
88 	atomic_t *stat = (atomic_t *)table->data;
89 
90 	if (!stat)
91 		return -EINVAL;
92 
93 	if (write)
94 		atomic_set(stat, 0);
95 	else {
96 		char str_buf[32];
97 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
98 		if (len >= 32)
99 			return -EFAULT;
100 		len = strlen(str_buf);
101 		if (*ppos > len) {
102 			*lenp = 0;
103 			return 0;
104 		}
105 		len -= *ppos;
106 		if (len > *lenp)
107 			len = *lenp;
108 		if (len && copy_to_user(buffer, str_buf, len))
109 			return -EFAULT;
110 		*lenp = len;
111 		*ppos += len;
112 	}
113 	return 0;
114 }
115 
116 static struct ctl_table_header *svcrdma_table_header;
117 static struct ctl_table svcrdma_parm_table[] = {
118 	{
119 		.procname	= "max_requests",
120 		.data		= &svcrdma_max_requests,
121 		.maxlen		= sizeof(unsigned int),
122 		.mode		= 0644,
123 		.proc_handler	= proc_dointvec_minmax,
124 		.extra1		= &min_max_requests,
125 		.extra2		= &max_max_requests
126 	},
127 	{
128 		.procname	= "max_req_size",
129 		.data		= &svcrdma_max_req_size,
130 		.maxlen		= sizeof(unsigned int),
131 		.mode		= 0644,
132 		.proc_handler	= proc_dointvec_minmax,
133 		.extra1		= &min_max_inline,
134 		.extra2		= &max_max_inline
135 	},
136 	{
137 		.procname	= "max_outbound_read_requests",
138 		.data		= &svcrdma_ord,
139 		.maxlen		= sizeof(unsigned int),
140 		.mode		= 0644,
141 		.proc_handler	= proc_dointvec_minmax,
142 		.extra1		= &min_ord,
143 		.extra2		= &max_ord,
144 	},
145 
146 	{
147 		.procname	= "rdma_stat_read",
148 		.data		= &rdma_stat_read,
149 		.maxlen		= sizeof(atomic_t),
150 		.mode		= 0644,
151 		.proc_handler	= read_reset_stat,
152 	},
153 	{
154 		.procname	= "rdma_stat_recv",
155 		.data		= &rdma_stat_recv,
156 		.maxlen		= sizeof(atomic_t),
157 		.mode		= 0644,
158 		.proc_handler	= read_reset_stat,
159 	},
160 	{
161 		.procname	= "rdma_stat_write",
162 		.data		= &rdma_stat_write,
163 		.maxlen		= sizeof(atomic_t),
164 		.mode		= 0644,
165 		.proc_handler	= read_reset_stat,
166 	},
167 	{
168 		.procname	= "rdma_stat_sq_starve",
169 		.data		= &rdma_stat_sq_starve,
170 		.maxlen		= sizeof(atomic_t),
171 		.mode		= 0644,
172 		.proc_handler	= read_reset_stat,
173 	},
174 	{
175 		.procname	= "rdma_stat_rq_starve",
176 		.data		= &rdma_stat_rq_starve,
177 		.maxlen		= sizeof(atomic_t),
178 		.mode		= 0644,
179 		.proc_handler	= read_reset_stat,
180 	},
181 	{
182 		.procname	= "rdma_stat_rq_poll",
183 		.data		= &rdma_stat_rq_poll,
184 		.maxlen		= sizeof(atomic_t),
185 		.mode		= 0644,
186 		.proc_handler	= read_reset_stat,
187 	},
188 	{
189 		.procname	= "rdma_stat_rq_prod",
190 		.data		= &rdma_stat_rq_prod,
191 		.maxlen		= sizeof(atomic_t),
192 		.mode		= 0644,
193 		.proc_handler	= read_reset_stat,
194 	},
195 	{
196 		.procname	= "rdma_stat_sq_poll",
197 		.data		= &rdma_stat_sq_poll,
198 		.maxlen		= sizeof(atomic_t),
199 		.mode		= 0644,
200 		.proc_handler	= read_reset_stat,
201 	},
202 	{
203 		.procname	= "rdma_stat_sq_prod",
204 		.data		= &rdma_stat_sq_prod,
205 		.maxlen		= sizeof(atomic_t),
206 		.mode		= 0644,
207 		.proc_handler	= read_reset_stat,
208 	},
209 	{ },
210 };
211 
212 static struct ctl_table svcrdma_table[] = {
213 	{
214 		.procname	= "svc_rdma",
215 		.mode		= 0555,
216 		.child		= svcrdma_parm_table
217 	},
218 	{ },
219 };
220 
221 static struct ctl_table svcrdma_root_table[] = {
222 	{
223 		.procname	= "sunrpc",
224 		.mode		= 0555,
225 		.child		= svcrdma_table
226 	},
227 	{ },
228 };
229 
230 void svc_rdma_cleanup(void)
231 {
232 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
233 	destroy_workqueue(svc_rdma_wq);
234 	if (svcrdma_table_header) {
235 		unregister_sysctl_table(svcrdma_table_header);
236 		svcrdma_table_header = NULL;
237 	}
238 	svc_unreg_xprt_class(&svc_rdma_class);
239 }
240 
241 int svc_rdma_init(void)
242 {
243 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
244 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
245 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
246 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
247 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
248 
249 	svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0);
250 	if (!svc_rdma_wq)
251 		return -ENOMEM;
252 
253 	if (!svcrdma_table_header)
254 		svcrdma_table_header =
255 			register_sysctl_table(svcrdma_root_table);
256 
257 	/* Register RDMA with the SVC transport switch */
258 	svc_reg_xprt_class(&svc_rdma_class);
259 	return 0;
260 }
261