net/sunrpc/xprtrdma/svc_rdma.c

Source file repositories/reference/linux-study-clean/net/sunrpc/xprtrdma/svc_rdma.c

File Facts

System
Linux kernel
Corpus path
net/sunrpc/xprtrdma/svc_rdma.c
Extension
.c
Size
8146 bytes
Lines
292
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: implementation source
Status
source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Copyright (c) 2015-2018 Oracle.  All rights reserved.
 * 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>

#define RPCDBG_FACILITY	RPCDBG_SVCXPRT

/* RPC/RDMA parameters */
unsigned int svcrdma_ord = 16;	/* historical default */
static unsigned int min_ord = 1;
static unsigned int max_ord = 255;
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_DEF_INLINE_THRESH;
static unsigned int min_max_inline = RPCRDMA_DEF_INLINE_THRESH;
static unsigned int max_max_inline = RPCRDMA_MAX_INLINE_THRESH;
static unsigned int svcrdma_stat_unused;
static unsigned int zero;

struct percpu_counter svcrdma_stat_read;
struct percpu_counter svcrdma_stat_recv;
struct percpu_counter svcrdma_stat_sq_starve;
struct percpu_counter svcrdma_stat_write;

enum {
	SVCRDMA_COUNTER_BUFSIZ	= sizeof(unsigned long long),
};

static int svcrdma_counter_handler(const struct ctl_table *table, int write,
				   void *buffer, size_t *lenp, loff_t *ppos)
{
	struct percpu_counter *stat = (struct percpu_counter *)table->data;
	char tmp[SVCRDMA_COUNTER_BUFSIZ + 1];
	int len;

	if (write) {
		percpu_counter_set(stat, 0);
		return 0;
	}

	len = snprintf(tmp, SVCRDMA_COUNTER_BUFSIZ, "%lld\n",
		       percpu_counter_sum_positive(stat));

Annotation

Implementation Notes