linux/net/sunrpc/xprtrdma/svc_rdma.c
Chuck Lever b623589dba svcrdma: Eliminate RPCRDMA_SQ_DEPTH_MULT
The Send Queue depth is temporarily reduced to 1 SQE per credit. The
new rdma_rw API does an internal computation, during QP creation, to
increase the depth of the Send Queue to handle RDMA Read and Write
operations.

This change has to come before the NFSD code paths are updated to
use the rdma_rw API. Without this patch, rdma_rw_init_qp() increases
the size of the SQ too much, resulting in memory allocation failures
during QP creation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 17:25:54 -04:00

268 lines
7.2 KiB
C

/*
* Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the BSD-type
* license below:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* Neither the name of the Network Appliance, Inc. nor the names of
* its contributors may be used to endorse or promote products
* derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Author: Tom Tucker <tom@opengridcomputing.com>
*/
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/sysctl.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/svc_rdma.h>
#include "xprt_rdma.h"
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
/* RPC/RDMA parameters */
unsigned int svcrdma_ord = RPCRDMA_ORD;
static unsigned int min_ord = 1;
static unsigned int max_ord = 4096;
unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS;
static unsigned int min_max_requests = 4;
static unsigned int max_max_requests = 16384;
unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
static unsigned int min_max_inline = 4096;
static unsigned int max_max_inline = 65536;
atomic_t rdma_stat_recv;
atomic_t rdma_stat_read;
atomic_t rdma_stat_write;
atomic_t rdma_stat_sq_starve;
atomic_t rdma_stat_rq_starve;
atomic_t rdma_stat_rq_poll;
atomic_t rdma_stat_rq_prod;
atomic_t rdma_stat_sq_poll;
atomic_t rdma_stat_sq_prod;
struct workqueue_struct *svc_rdma_wq;
/*
* This function implements reading and resetting an atomic_t stat
* variable through read/write to a proc file. Any write to the file
* resets the associated statistic to zero. Any read returns it's
* current value.
*/
static int read_reset_stat(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
atomic_t *stat = (atomic_t *)table->data;
if (!stat)
return -EINVAL;
if (write)
atomic_set(stat, 0);
else {
char str_buf[32];
char *data;
int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
if (len >= 32)
return -EFAULT;
len = strlen(str_buf);
if (*ppos > len) {
*lenp = 0;
return 0;
}
data = &str_buf[*ppos];
len -= *ppos;
if (len > *lenp)
len = *lenp;
if (len && copy_to_user(buffer, str_buf, len))
return -EFAULT;
*lenp = len;
*ppos += len;
}
return 0;
}
static struct ctl_table_header *svcrdma_table_header;
static struct ctl_table svcrdma_parm_table[] = {
{
.procname = "max_requests",
.data = &svcrdma_max_requests,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_max_requests,
.extra2 = &max_max_requests
},
{
.procname = "max_req_size",
.data = &svcrdma_max_req_size,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_max_inline,
.extra2 = &max_max_inline
},
{
.procname = "max_outbound_read_requests",
.data = &svcrdma_ord,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_ord,
.extra2 = &max_ord,
},
{
.procname = "rdma_stat_read",
.data = &rdma_stat_read,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_recv",
.data = &rdma_stat_recv,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_write",
.data = &rdma_stat_write,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_sq_starve",
.data = &rdma_stat_sq_starve,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_rq_starve",
.data = &rdma_stat_rq_starve,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_rq_poll",
.data = &rdma_stat_rq_poll,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_rq_prod",
.data = &rdma_stat_rq_prod,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_sq_poll",
.data = &rdma_stat_sq_poll,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{
.procname = "rdma_stat_sq_prod",
.data = &rdma_stat_sq_prod,
.maxlen = sizeof(atomic_t),
.mode = 0644,
.proc_handler = read_reset_stat,
},
{ },
};
static struct ctl_table svcrdma_table[] = {
{
.procname = "svc_rdma",
.mode = 0555,
.child = svcrdma_parm_table
},
{ },
};
static struct ctl_table svcrdma_root_table[] = {
{
.procname = "sunrpc",
.mode = 0555,
.child = svcrdma_table
},
{ },
};
void svc_rdma_cleanup(void)
{
dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
destroy_workqueue(svc_rdma_wq);
if (svcrdma_table_header) {
unregister_sysctl_table(svcrdma_table_header);
svcrdma_table_header = NULL;
}
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
svc_unreg_xprt_class(&svc_rdma_bc_class);
#endif
svc_unreg_xprt_class(&svc_rdma_class);
}
int svc_rdma_init(void)
{
dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
dprintk("\tsvcrdma_ord : %d\n", svcrdma_ord);
dprintk("\tmax_requests : %u\n", svcrdma_max_requests);
dprintk("\tmax_bc_requests : %u\n", svcrdma_max_bc_requests);
dprintk("\tmax_inline : %d\n", svcrdma_max_req_size);
svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0);
if (!svc_rdma_wq)
return -ENOMEM;
if (!svcrdma_table_header)
svcrdma_table_header =
register_sysctl_table(svcrdma_root_table);
/* Register RDMA with the SVC transport switch */
svc_reg_xprt_class(&svc_rdma_class);
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
svc_reg_xprt_class(&svc_rdma_bc_class);
#endif
return 0;
}