xref: /linux/net/sunrpc/xprtrdma/svc_rdma.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the BSD-type
8  * license below:
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  *
14  *      Redistributions of source code must retain the above copyright
15  *      notice, this list of conditions and the following disclaimer.
16  *
17  *      Redistributions in binary form must reproduce the above
18  *      copyright notice, this list of conditions and the following
19  *      disclaimer in the documentation and/or other materials provided
20  *      with the distribution.
21  *
22  *      Neither the name of the Network Appliance, Inc. nor the names of
23  *      its contributors may be used to endorse or promote products
24  *      derived from this software without specific prior written
25  *      permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38  *
39  * Author: Tom Tucker <tom@opengridcomputing.com>
40  */
41 
42 #include <linux/slab.h>
43 #include <linux/fs.h>
44 #include <linux/sysctl.h>
45 #include <linux/workqueue.h>
46 #include <linux/sunrpc/clnt.h>
47 #include <linux/sunrpc/sched.h>
48 #include <linux/sunrpc/svc_rdma.h>
49 #include "xprt_rdma.h"
50 
51 #define RPCDBG_FACILITY	RPCDBG_SVCXPRT
52 
53 /* RPC/RDMA parameters */
54 unsigned int svcrdma_ord = RPCRDMA_ORD;
55 static unsigned int min_ord = 1;
56 static unsigned int max_ord = 4096;
57 unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
58 unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS;
59 static unsigned int min_max_requests = 4;
60 static unsigned int max_max_requests = 16384;
61 unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
62 static unsigned int min_max_inline = 4096;
63 static unsigned int max_max_inline = 65536;
64 
65 atomic_t rdma_stat_recv;
66 atomic_t rdma_stat_read;
67 atomic_t rdma_stat_write;
68 atomic_t rdma_stat_sq_starve;
69 atomic_t rdma_stat_rq_starve;
70 atomic_t rdma_stat_rq_poll;
71 atomic_t rdma_stat_rq_prod;
72 atomic_t rdma_stat_sq_poll;
73 atomic_t rdma_stat_sq_prod;
74 
75 struct workqueue_struct *svc_rdma_wq;
76 
77 /*
78  * This function implements reading and resetting an atomic_t stat
79  * variable through read/write to a proc file. Any write to the file
80  * resets the associated statistic to zero. Any read returns it's
81  * current value.
82  */
83 static int read_reset_stat(struct ctl_table *table, int write,
84 			   void __user *buffer, size_t *lenp,
85 			   loff_t *ppos)
86 {
87 	atomic_t *stat = (atomic_t *)table->data;
88 
89 	if (!stat)
90 		return -EINVAL;
91 
92 	if (write)
93 		atomic_set(stat, 0);
94 	else {
95 		char str_buf[32];
96 		char *data;
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 		data = &str_buf[*ppos];
106 		len -= *ppos;
107 		if (len > *lenp)
108 			len = *lenp;
109 		if (len && copy_to_user(buffer, str_buf, len))
110 			return -EFAULT;
111 		*lenp = len;
112 		*ppos += len;
113 	}
114 	return 0;
115 }
116 
117 static struct ctl_table_header *svcrdma_table_header;
118 static struct ctl_table svcrdma_parm_table[] = {
119 	{
120 		.procname	= "max_requests",
121 		.data		= &svcrdma_max_requests,
122 		.maxlen		= sizeof(unsigned int),
123 		.mode		= 0644,
124 		.proc_handler	= proc_dointvec_minmax,
125 		.extra1		= &min_max_requests,
126 		.extra2		= &max_max_requests
127 	},
128 	{
129 		.procname	= "max_req_size",
130 		.data		= &svcrdma_max_req_size,
131 		.maxlen		= sizeof(unsigned int),
132 		.mode		= 0644,
133 		.proc_handler	= proc_dointvec_minmax,
134 		.extra1		= &min_max_inline,
135 		.extra2		= &max_max_inline
136 	},
137 	{
138 		.procname	= "max_outbound_read_requests",
139 		.data		= &svcrdma_ord,
140 		.maxlen		= sizeof(unsigned int),
141 		.mode		= 0644,
142 		.proc_handler	= proc_dointvec_minmax,
143 		.extra1		= &min_ord,
144 		.extra2		= &max_ord,
145 	},
146 
147 	{
148 		.procname	= "rdma_stat_read",
149 		.data		= &rdma_stat_read,
150 		.maxlen		= sizeof(atomic_t),
151 		.mode		= 0644,
152 		.proc_handler	= read_reset_stat,
153 	},
154 	{
155 		.procname	= "rdma_stat_recv",
156 		.data		= &rdma_stat_recv,
157 		.maxlen		= sizeof(atomic_t),
158 		.mode		= 0644,
159 		.proc_handler	= read_reset_stat,
160 	},
161 	{
162 		.procname	= "rdma_stat_write",
163 		.data		= &rdma_stat_write,
164 		.maxlen		= sizeof(atomic_t),
165 		.mode		= 0644,
166 		.proc_handler	= read_reset_stat,
167 	},
168 	{
169 		.procname	= "rdma_stat_sq_starve",
170 		.data		= &rdma_stat_sq_starve,
171 		.maxlen		= sizeof(atomic_t),
172 		.mode		= 0644,
173 		.proc_handler	= read_reset_stat,
174 	},
175 	{
176 		.procname	= "rdma_stat_rq_starve",
177 		.data		= &rdma_stat_rq_starve,
178 		.maxlen		= sizeof(atomic_t),
179 		.mode		= 0644,
180 		.proc_handler	= read_reset_stat,
181 	},
182 	{
183 		.procname	= "rdma_stat_rq_poll",
184 		.data		= &rdma_stat_rq_poll,
185 		.maxlen		= sizeof(atomic_t),
186 		.mode		= 0644,
187 		.proc_handler	= read_reset_stat,
188 	},
189 	{
190 		.procname	= "rdma_stat_rq_prod",
191 		.data		= &rdma_stat_rq_prod,
192 		.maxlen		= sizeof(atomic_t),
193 		.mode		= 0644,
194 		.proc_handler	= read_reset_stat,
195 	},
196 	{
197 		.procname	= "rdma_stat_sq_poll",
198 		.data		= &rdma_stat_sq_poll,
199 		.maxlen		= sizeof(atomic_t),
200 		.mode		= 0644,
201 		.proc_handler	= read_reset_stat,
202 	},
203 	{
204 		.procname	= "rdma_stat_sq_prod",
205 		.data		= &rdma_stat_sq_prod,
206 		.maxlen		= sizeof(atomic_t),
207 		.mode		= 0644,
208 		.proc_handler	= read_reset_stat,
209 	},
210 	{ },
211 };
212 
213 static struct ctl_table svcrdma_table[] = {
214 	{
215 		.procname	= "svc_rdma",
216 		.mode		= 0555,
217 		.child		= svcrdma_parm_table
218 	},
219 	{ },
220 };
221 
222 static struct ctl_table svcrdma_root_table[] = {
223 	{
224 		.procname	= "sunrpc",
225 		.mode		= 0555,
226 		.child		= svcrdma_table
227 	},
228 	{ },
229 };
230 
231 void svc_rdma_cleanup(void)
232 {
233 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
234 	destroy_workqueue(svc_rdma_wq);
235 	if (svcrdma_table_header) {
236 		unregister_sysctl_table(svcrdma_table_header);
237 		svcrdma_table_header = NULL;
238 	}
239 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
240 	svc_unreg_xprt_class(&svc_rdma_bc_class);
241 #endif
242 	svc_unreg_xprt_class(&svc_rdma_class);
243 }
244 
245 int svc_rdma_init(void)
246 {
247 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
248 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
249 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
250 	dprintk("\tsq_depth         : %u\n",
251 		svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT);
252 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
253 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
254 
255 	svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0);
256 	if (!svc_rdma_wq)
257 		return -ENOMEM;
258 
259 	if (!svcrdma_table_header)
260 		svcrdma_table_header =
261 			register_sysctl_table(svcrdma_root_table);
262 
263 	/* Register RDMA with the SVC transport switch */
264 	svc_reg_xprt_class(&svc_rdma_class);
265 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
266 	svc_reg_xprt_class(&svc_rdma_bc_class);
267 #endif
268 	return 0;
269 }
270