xref: /openbmc/linux/net/sunrpc/xprtrdma/svc_rdma.c (revision 323dd2c3)
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 /*
77  * This function implements reading and resetting an atomic_t stat
78  * variable through read/write to a proc file. Any write to the file
79  * resets the associated statistic to zero. Any read returns it's
80  * current value.
81  */
82 static int read_reset_stat(struct ctl_table *table, int write,
83 			   void __user *buffer, size_t *lenp,
84 			   loff_t *ppos)
85 {
86 	atomic_t *stat = (atomic_t *)table->data;
87 
88 	if (!stat)
89 		return -EINVAL;
90 
91 	if (write)
92 		atomic_set(stat, 0);
93 	else {
94 		char str_buf[32];
95 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
96 		if (len >= 32)
97 			return -EFAULT;
98 		len = strlen(str_buf);
99 		if (*ppos > len) {
100 			*lenp = 0;
101 			return 0;
102 		}
103 		len -= *ppos;
104 		if (len > *lenp)
105 			len = *lenp;
106 		if (len && copy_to_user(buffer, str_buf, len))
107 			return -EFAULT;
108 		*lenp = len;
109 		*ppos += len;
110 	}
111 	return 0;
112 }
113 
114 static struct ctl_table_header *svcrdma_table_header;
115 static struct ctl_table svcrdma_parm_table[] = {
116 	{
117 		.procname	= "max_requests",
118 		.data		= &svcrdma_max_requests,
119 		.maxlen		= sizeof(unsigned int),
120 		.mode		= 0644,
121 		.proc_handler	= proc_dointvec_minmax,
122 		.extra1		= &min_max_requests,
123 		.extra2		= &max_max_requests
124 	},
125 	{
126 		.procname	= "max_req_size",
127 		.data		= &svcrdma_max_req_size,
128 		.maxlen		= sizeof(unsigned int),
129 		.mode		= 0644,
130 		.proc_handler	= proc_dointvec_minmax,
131 		.extra1		= &min_max_inline,
132 		.extra2		= &max_max_inline
133 	},
134 	{
135 		.procname	= "max_outbound_read_requests",
136 		.data		= &svcrdma_ord,
137 		.maxlen		= sizeof(unsigned int),
138 		.mode		= 0644,
139 		.proc_handler	= proc_dointvec_minmax,
140 		.extra1		= &min_ord,
141 		.extra2		= &max_ord,
142 	},
143 
144 	{
145 		.procname	= "rdma_stat_read",
146 		.data		= &rdma_stat_read,
147 		.maxlen		= sizeof(atomic_t),
148 		.mode		= 0644,
149 		.proc_handler	= read_reset_stat,
150 	},
151 	{
152 		.procname	= "rdma_stat_recv",
153 		.data		= &rdma_stat_recv,
154 		.maxlen		= sizeof(atomic_t),
155 		.mode		= 0644,
156 		.proc_handler	= read_reset_stat,
157 	},
158 	{
159 		.procname	= "rdma_stat_write",
160 		.data		= &rdma_stat_write,
161 		.maxlen		= sizeof(atomic_t),
162 		.mode		= 0644,
163 		.proc_handler	= read_reset_stat,
164 	},
165 	{
166 		.procname	= "rdma_stat_sq_starve",
167 		.data		= &rdma_stat_sq_starve,
168 		.maxlen		= sizeof(atomic_t),
169 		.mode		= 0644,
170 		.proc_handler	= read_reset_stat,
171 	},
172 	{
173 		.procname	= "rdma_stat_rq_starve",
174 		.data		= &rdma_stat_rq_starve,
175 		.maxlen		= sizeof(atomic_t),
176 		.mode		= 0644,
177 		.proc_handler	= read_reset_stat,
178 	},
179 	{
180 		.procname	= "rdma_stat_rq_poll",
181 		.data		= &rdma_stat_rq_poll,
182 		.maxlen		= sizeof(atomic_t),
183 		.mode		= 0644,
184 		.proc_handler	= read_reset_stat,
185 	},
186 	{
187 		.procname	= "rdma_stat_rq_prod",
188 		.data		= &rdma_stat_rq_prod,
189 		.maxlen		= sizeof(atomic_t),
190 		.mode		= 0644,
191 		.proc_handler	= read_reset_stat,
192 	},
193 	{
194 		.procname	= "rdma_stat_sq_poll",
195 		.data		= &rdma_stat_sq_poll,
196 		.maxlen		= sizeof(atomic_t),
197 		.mode		= 0644,
198 		.proc_handler	= read_reset_stat,
199 	},
200 	{
201 		.procname	= "rdma_stat_sq_prod",
202 		.data		= &rdma_stat_sq_prod,
203 		.maxlen		= sizeof(atomic_t),
204 		.mode		= 0644,
205 		.proc_handler	= read_reset_stat,
206 	},
207 	{ },
208 };
209 
210 static struct ctl_table svcrdma_table[] = {
211 	{
212 		.procname	= "svc_rdma",
213 		.mode		= 0555,
214 		.child		= svcrdma_parm_table
215 	},
216 	{ },
217 };
218 
219 static struct ctl_table svcrdma_root_table[] = {
220 	{
221 		.procname	= "sunrpc",
222 		.mode		= 0555,
223 		.child		= svcrdma_table
224 	},
225 	{ },
226 };
227 
228 void svc_rdma_cleanup(void)
229 {
230 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
231 	if (svcrdma_table_header) {
232 		unregister_sysctl_table(svcrdma_table_header);
233 		svcrdma_table_header = NULL;
234 	}
235 	svc_unreg_xprt_class(&svc_rdma_class);
236 }
237 
238 int svc_rdma_init(void)
239 {
240 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
241 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
242 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
243 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
244 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
245 
246 	if (!svcrdma_table_header)
247 		svcrdma_table_header =
248 			register_sysctl_table(svcrdma_root_table);
249 
250 	/* Register RDMA with the SVC transport switch */
251 	svc_reg_xprt_class(&svc_rdma_class);
252 	return 0;
253 }
254