net/rds/tcp_stats.c

   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
  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 }