1 /*
2  * Copyright (c) 2006 Oracle.  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
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 #include <linux/percpu.h>
34 #include <linux/seq_file.h>
35 #include <linux/proc_fs.h>
36 
37 #include "rds.h"
38 #include "tcp.h"
39 
40 DEFINE_PER_CPU(struct rds_tcp_statistics, rds_tcp_stats)
41 	____cacheline_aligned;
42 
43 static const char * const rds_tcp_stat_names[] = {
44 	"tcp_data_ready_calls",
45 	"tcp_write_space_calls",
46 	"tcp_sndbuf_full",
47 	"tcp_connect_raced",
48 	"tcp_listen_closed_stale",
49 };
50 
rds_tcp_stats_info_copy(struct rds_info_iterator * iter,unsigned int avail)51 unsigned int rds_tcp_stats_info_copy(struct rds_info_iterator *iter,
52 				     unsigned int avail)
53 {
54 	struct rds_tcp_statistics stats = {0, };
55 	uint64_t *src;
56 	uint64_t *sum;
57 	size_t i;
58 	int cpu;
59 
60 	if (avail < ARRAY_SIZE(rds_tcp_stat_names))
61 		goto out;
62 
63 	for_each_online_cpu(cpu) {
64 		src = (uint64_t *)&(per_cpu(rds_tcp_stats, cpu));
65 		sum = (uint64_t *)&stats;
66 		for (i = 0; i < sizeof(stats) / sizeof(uint64_t); i++)
67 			*(sum++) += *(src++);
68 	}
69 
70 	rds_stats_info_copy(iter, (uint64_t *)&stats, rds_tcp_stat_names,
71 			    ARRAY_SIZE(rds_tcp_stat_names));
72 out:
73 	return ARRAY_SIZE(rds_tcp_stat_names);
74 }
75