LXR linux/net/sctp/objcnt.c

   1/* SCTP kernel implementation
   2 * (C) Copyright IBM Corp. 2001, 2004
   3 *
   4 * This file is part of the SCTP kernel implementation
   5 *
   6 * Support for memory object debugging.  This allows one to monitor the
   7 * object allocations/deallocations for types instrumented for this
   8 * via the proc fs.
   9 *
  10 * This SCTP implementation is free software;
  11 * you can redistribute it and/or modify it under the terms of
  12 * the GNU General Public License as published by
  13 * the Free Software Foundation; either version 2, or (at your option)
  14 * any later version.
  15 *
  16 * This SCTP implementation is distributed in the hope that it
  17 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  18 *                 ************************
  19 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  20 * See the GNU General Public License for more details.
  21 *
  22 * You should have received a copy of the GNU General Public License
  23 * along with GNU CC; see the file COPYING.  If not, see
  24 * <http://www.gnu.org/licenses/>.
  25 *
  26 * Please send any bug reports or fixes you make to the
  27 * email address(es):
  28 *    lksctp developers <linux-sctp@vger.kernel.org>
  29 *
  30 * Written or modified by:
  31 *    Jon Grimm             <jgrimm@us.ibm.com>
  32 */
  33
  34#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  35
  36#include <linux/kernel.h>
  37#include <net/sctp/sctp.h>
  38
  39/*
  40 * Global counters to count raw object allocation counts.
  41 * To add new counters, choose a unique suffix for the variable
  42 * name as the helper macros key off this suffix to make
  43 * life easier for the programmer.
  44 */
  45
  46SCTP_DBG_OBJCNT(sock);
  47SCTP_DBG_OBJCNT(ep);
  48SCTP_DBG_OBJCNT(transport);
  49SCTP_DBG_OBJCNT(assoc);
  50SCTP_DBG_OBJCNT(bind_addr);
  51SCTP_DBG_OBJCNT(bind_bucket);
  52SCTP_DBG_OBJCNT(chunk);
  53SCTP_DBG_OBJCNT(addr);
  54SCTP_DBG_OBJCNT(datamsg);
  55SCTP_DBG_OBJCNT(keys);
  56
  57/* An array to make it easy to pretty print the debug information
  58 * to the proc fs.
  59 */
  60static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
  61        SCTP_DBG_OBJCNT_ENTRY(sock),
  62        SCTP_DBG_OBJCNT_ENTRY(ep),
  63        SCTP_DBG_OBJCNT_ENTRY(assoc),
  64        SCTP_DBG_OBJCNT_ENTRY(transport),
  65        SCTP_DBG_OBJCNT_ENTRY(chunk),
  66        SCTP_DBG_OBJCNT_ENTRY(bind_addr),
  67        SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
  68        SCTP_DBG_OBJCNT_ENTRY(addr),
  69        SCTP_DBG_OBJCNT_ENTRY(datamsg),
  70        SCTP_DBG_OBJCNT_ENTRY(keys),
  71};
  72
  73/* Callback from procfs to read out objcount information.
  74 * Walk through the entries in the sctp_dbg_objcnt array, dumping
  75 * the raw object counts for each monitored type.
  76 */
  77static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
  78{
  79        int i;
  80
  81        i = (int)*(loff_t *)v;
  82        seq_setwidth(seq, 127);
  83        seq_printf(seq, "%s: %d", sctp_dbg_objcnt[i].label,
  84                                atomic_read(sctp_dbg_objcnt[i].counter));
  85        seq_pad(seq, '\n');
  86        return 0;
  87}
  88
  89static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
  90{
  91        return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
  92}
  93
  94static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
  95{
  96}
  97
  98static void *sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  99{
 100        ++*pos;
 101        return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
 102}
 103
 104static const struct seq_operations sctp_objcnt_seq_ops = {
 105        .start = sctp_objcnt_seq_start,
 106        .next  = sctp_objcnt_seq_next,
 107        .stop  = sctp_objcnt_seq_stop,
 108        .show  = sctp_objcnt_seq_show,
 109};
 110
 111static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
 112{
 113        return seq_open(file, &sctp_objcnt_seq_ops);
 114}
 115
 116static const struct file_operations sctp_objcnt_ops = {
 117        .open    = sctp_objcnt_seq_open,
 118        .read    = seq_read,
 119        .llseek  = seq_lseek,
 120        .release = seq_release,
 121};
 122
 123/* Initialize the objcount in the proc filesystem.  */
 124void sctp_dbg_objcnt_init(struct net *net)
 125{
 126        struct proc_dir_entry *ent;
 127
 128        ent = proc_create("sctp_dbg_objcnt", 0,
 129                          net->sctp.proc_net_sctp, &sctp_objcnt_ops);
 130        if (!ent)
 131                pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.\n");
 132}
 133
 134/* Cleanup the objcount entry in the proc filesystem.  */
 135void sctp_dbg_objcnt_exit(struct net *net)
 136{
 137        remove_proc_entry("sctp_dbg_objcnt", net->sctp.proc_net_sctp);
 138}
 139
 140
 141