svc_rdma.c

  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 */
 55unsigned int svcrdma_ord = 16;	/* historical default */
 56static unsigned int min_ord = 1;
 57static unsigned int max_ord = 255;
 58unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
 59unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS;
 60static unsigned int min_max_requests = 4;
 61static unsigned int max_max_requests = 16384;
 62unsigned int svcrdma_max_req_size = RPCRDMA_DEF_INLINE_THRESH;
 63static unsigned int min_max_inline = RPCRDMA_DEF_INLINE_THRESH;
 64static unsigned int max_max_inline = RPCRDMA_MAX_INLINE_THRESH;
 65static unsigned int svcrdma_stat_unused;
 66static unsigned int zero;
 67
 68struct percpu_counter svcrdma_stat_read;
 69struct percpu_counter svcrdma_stat_recv;
 70struct percpu_counter svcrdma_stat_sq_starve;
 71struct percpu_counter svcrdma_stat_write;
 72
 73enum {
 74	SVCRDMA_COUNTER_BUFSIZ	= sizeof(unsigned long long),
 75};
 76
 77static 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
109static struct ctl_table_header *svcrdma_table_header;
110static 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
214static 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
227static 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
254err_write:
255	rc = -ENOMEM;
256	percpu_counter_destroy(&svcrdma_stat_write);
257err_sq:
258	percpu_counter_destroy(&svcrdma_stat_sq_starve);
259err_recv:
260	percpu_counter_destroy(&svcrdma_stat_recv);
261err_read:
262	percpu_counter_destroy(&svcrdma_stat_read);
263err:
264	return rc;
265}
266
267struct workqueue_struct *svcrdma_wq;
268
269void 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
283int 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}