xref: /openbmc/linux/net/sunrpc/xprtrdma/svc_rdma.c (revision e15a5365)
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 *buffer, size_t *lenp, loff_t *ppos)
84 {
85 	atomic_t *stat = (atomic_t *)table->data;
86 
87 	if (!stat)
88 		return -EINVAL;
89 
90 	if (write)
91 		atomic_set(stat, 0);
92 	else {
93 		char str_buf[32];
94 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
95 		if (len >= 32)
96 			return -EFAULT;
97 		len = strlen(str_buf);
98 		if (*ppos > len) {
99 			*lenp = 0;
100 			return 0;
101 		}
102 		len -= *ppos;
103 		if (len > *lenp)
104 			len = *lenp;
105 		if (len)
106 			memcpy(buffer, str_buf, len);
107 		*lenp = len;
108 		*ppos += len;
109 	}
110 	return 0;
111 }
112 
113 static struct ctl_table_header *svcrdma_table_header;
114 static struct ctl_table svcrdma_parm_table[] = {
115 	{
116 		.procname	= "max_requests",
117 		.data		= &svcrdma_max_requests,
118 		.maxlen		= sizeof(unsigned int),
119 		.mode		= 0644,
120 		.proc_handler	= proc_dointvec_minmax,
121 		.extra1		= &min_max_requests,
122 		.extra2		= &max_max_requests
123 	},
124 	{
125 		.procname	= "max_req_size",
126 		.data		= &svcrdma_max_req_size,
127 		.maxlen		= sizeof(unsigned int),
128 		.mode		= 0644,
129 		.proc_handler	= proc_dointvec_minmax,
130 		.extra1		= &min_max_inline,
131 		.extra2		= &max_max_inline
132 	},
133 	{
134 		.procname	= "max_outbound_read_requests",
135 		.data		= &svcrdma_ord,
136 		.maxlen		= sizeof(unsigned int),
137 		.mode		= 0644,
138 		.proc_handler	= proc_dointvec_minmax,
139 		.extra1		= &min_ord,
140 		.extra2		= &max_ord,
141 	},
142 
143 	{
144 		.procname	= "rdma_stat_read",
145 		.data		= &rdma_stat_read,
146 		.maxlen		= sizeof(atomic_t),
147 		.mode		= 0644,
148 		.proc_handler	= read_reset_stat,
149 	},
150 	{
151 		.procname	= "rdma_stat_recv",
152 		.data		= &rdma_stat_recv,
153 		.maxlen		= sizeof(atomic_t),
154 		.mode		= 0644,
155 		.proc_handler	= read_reset_stat,
156 	},
157 	{
158 		.procname	= "rdma_stat_write",
159 		.data		= &rdma_stat_write,
160 		.maxlen		= sizeof(atomic_t),
161 		.mode		= 0644,
162 		.proc_handler	= read_reset_stat,
163 	},
164 	{
165 		.procname	= "rdma_stat_sq_starve",
166 		.data		= &rdma_stat_sq_starve,
167 		.maxlen		= sizeof(atomic_t),
168 		.mode		= 0644,
169 		.proc_handler	= read_reset_stat,
170 	},
171 	{
172 		.procname	= "rdma_stat_rq_starve",
173 		.data		= &rdma_stat_rq_starve,
174 		.maxlen		= sizeof(atomic_t),
175 		.mode		= 0644,
176 		.proc_handler	= read_reset_stat,
177 	},
178 	{
179 		.procname	= "rdma_stat_rq_poll",
180 		.data		= &rdma_stat_rq_poll,
181 		.maxlen		= sizeof(atomic_t),
182 		.mode		= 0644,
183 		.proc_handler	= read_reset_stat,
184 	},
185 	{
186 		.procname	= "rdma_stat_rq_prod",
187 		.data		= &rdma_stat_rq_prod,
188 		.maxlen		= sizeof(atomic_t),
189 		.mode		= 0644,
190 		.proc_handler	= read_reset_stat,
191 	},
192 	{
193 		.procname	= "rdma_stat_sq_poll",
194 		.data		= &rdma_stat_sq_poll,
195 		.maxlen		= sizeof(atomic_t),
196 		.mode		= 0644,
197 		.proc_handler	= read_reset_stat,
198 	},
199 	{
200 		.procname	= "rdma_stat_sq_prod",
201 		.data		= &rdma_stat_sq_prod,
202 		.maxlen		= sizeof(atomic_t),
203 		.mode		= 0644,
204 		.proc_handler	= read_reset_stat,
205 	},
206 	{ },
207 };
208 
209 static struct ctl_table svcrdma_table[] = {
210 	{
211 		.procname	= "svc_rdma",
212 		.mode		= 0555,
213 		.child		= svcrdma_parm_table
214 	},
215 	{ },
216 };
217 
218 static struct ctl_table svcrdma_root_table[] = {
219 	{
220 		.procname	= "sunrpc",
221 		.mode		= 0555,
222 		.child		= svcrdma_table
223 	},
224 	{ },
225 };
226 
227 void svc_rdma_cleanup(void)
228 {
229 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
230 	if (svcrdma_table_header) {
231 		unregister_sysctl_table(svcrdma_table_header);
232 		svcrdma_table_header = NULL;
233 	}
234 	svc_unreg_xprt_class(&svc_rdma_class);
235 }
236 
237 int svc_rdma_init(void)
238 {
239 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
240 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
241 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
242 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
243 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
244 
245 	if (!svcrdma_table_header)
246 		svcrdma_table_header =
247 			register_sysctl_table(svcrdma_root_table);
248 
249 	/* Register RDMA with the SVC transport switch */
250 	svc_reg_xprt_class(&svc_rdma_class);
251 	return 0;
252 }
253