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, write to
  24  * the Free Software Foundation, 59 Temple Place - Suite 330,
  25  * Boston, MA 02111-1307, USA.
  26  *
  27  * Please send any bug reports or fixes you make to the
  28  * email address(es):
  29  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  30  *
  31  * Or submit a bug report through the following website:
  32  *    http://www.sf.net/projects/lksctp
  33  *
  34  * Written or modified by:
  35  *    Jon Grimm             <jgrimm@us.ibm.com>
  36  *
  37  * Any bugs reported given to us we will try to fix... any fixes shared will
  38  * be incorporated into the next SCTP release.
  39  */
  40
  41 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  42
  43 #include <linux/kernel.h>
  44 #include <net/sctp/sctp.h>
  45
  46 /*
  47  * Global counters to count raw object allocation counts.
  48  * To add new counters, choose a unique suffix for the variable
  49  * name as the helper macros key off this suffix to make
  50  * life easier for the programmer.
  51  */
  52
  53 SCTP_DBG_OBJCNT(sock);
  54 SCTP_DBG_OBJCNT(ep);
  55 SCTP_DBG_OBJCNT(transport);
  56 SCTP_DBG_OBJCNT(assoc);
  57 SCTP_DBG_OBJCNT(bind_addr);
  58 SCTP_DBG_OBJCNT(bind_bucket);
  59 SCTP_DBG_OBJCNT(chunk);
  60 SCTP_DBG_OBJCNT(addr);
  61 SCTP_DBG_OBJCNT(ssnmap);
  62 SCTP_DBG_OBJCNT(datamsg);
  63 SCTP_DBG_OBJCNT(keys);
  64
  65 /* An array to make it easy to pretty print the debug information
  66  * to the proc fs.
  67  */
  68 static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
  69         SCTP_DBG_OBJCNT_ENTRY(sock),
  70         SCTP_DBG_OBJCNT_ENTRY(ep),
  71         SCTP_DBG_OBJCNT_ENTRY(assoc),
  72         SCTP_DBG_OBJCNT_ENTRY(transport),
  73         SCTP_DBG_OBJCNT_ENTRY(chunk),
  74         SCTP_DBG_OBJCNT_ENTRY(bind_addr),
  75         SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
  76         SCTP_DBG_OBJCNT_ENTRY(addr),
  77         SCTP_DBG_OBJCNT_ENTRY(ssnmap),
  78         SCTP_DBG_OBJCNT_ENTRY(datamsg),
  79         SCTP_DBG_OBJCNT_ENTRY(keys),
  80 };
  81
  82 /* Callback from procfs to read out objcount information.
  83  * Walk through the entries in the sctp_dbg_objcnt array, dumping
  84  * the raw object counts for each monitored type.
  85  */
  86 static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
  87 {
  88         int i, len;
  89
  90         i = (int)*(loff_t *)v;
  91         seq_printf(seq, "%s: %d%n", sctp_dbg_objcnt[i].label,
  92                                 atomic_read(sctp_dbg_objcnt[i].counter), &len);
  93         seq_printf(seq, "%*s\n", 127 - len, "");
  94         return 0;
  95 }
  96
  97 static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
  98 {
  99         return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
 100 }
 101
 102 static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
 103 {
 104 }
 105
 106 static void * sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 107 {
 108         ++*pos;
 109         return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
 110 }
 111
 112 static const struct seq_operations sctp_objcnt_seq_ops = {
 113         .start = sctp_objcnt_seq_start,
 114         .next  = sctp_objcnt_seq_next,
 115         .stop  = sctp_objcnt_seq_stop,
 116         .show  = sctp_objcnt_seq_show,
 117 };
 118
 119 static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
 120 {
 121         return seq_open(file, &sctp_objcnt_seq_ops);
 122 }
 123
 124 static const struct file_operations sctp_objcnt_ops = {
 125         .open    = sctp_objcnt_seq_open,
 126         .read    = seq_read,
 127         .llseek  = seq_lseek,
 128         .release = seq_release,
 129 };
 130
 131 /* Initialize the objcount in the proc filesystem.  */
 132 void sctp_dbg_objcnt_init(void)
 133 {
 134         struct proc_dir_entry *ent;
 135
 136         ent = proc_create("sctp_dbg_objcnt", 0,
 137                           proc_net_sctp, &sctp_objcnt_ops);
 138         if (!ent)
 139                 pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.\n");
 140 }
 141
 142 /* Cleanup the objcount entry in the proc filesystem.  */
 143 void sctp_dbg_objcnt_exit(void)
 144 {
 145         remove_proc_entry("sctp_dbg_objcnt", proc_net_sctp);
 146 }
 147
 148