LXR linux/net/sctp/objcnt.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* SCTP kernel implementation
   3 * (C) Copyright IBM Corp. 2001, 2004
   4 *
   5 * This file is part of the SCTP kernel implementation
   6 *
   7 * Support for memory object debugging.  This allows one to monitor the
   8 * object allocations/deallocations for types instrumented for this
   9 * via the proc fs.
  10 *
  11 * Please send any bug reports or fixes you make to the
  12 * email address(es):
  13 *    lksctp developers <linux-sctp@vger.kernel.org>
  14 *
  15 * Written or modified by:
  16 *    Jon Grimm             <jgrimm@us.ibm.com>
  17 */
  18
  19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21#include <linux/kernel.h>
  22#include <net/sctp/sctp.h>
  23
  24/*
  25 * Global counters to count raw object allocation counts.
  26 * To add new counters, choose a unique suffix for the variable
  27 * name as the helper macros key off this suffix to make
  28 * life easier for the programmer.
  29 */
  30
  31SCTP_DBG_OBJCNT(sock);
  32SCTP_DBG_OBJCNT(ep);
  33SCTP_DBG_OBJCNT(transport);
  34SCTP_DBG_OBJCNT(assoc);
  35SCTP_DBG_OBJCNT(bind_addr);
  36SCTP_DBG_OBJCNT(bind_bucket);
  37SCTP_DBG_OBJCNT(chunk);
  38SCTP_DBG_OBJCNT(addr);
  39SCTP_DBG_OBJCNT(datamsg);
  40SCTP_DBG_OBJCNT(keys);
  41
  42/* An array to make it easy to pretty print the debug information
  43 * to the proc fs.
  44 */
  45static struct sctp_dbg_objcnt_entry sctp_dbg_objcnt[] = {
  46        SCTP_DBG_OBJCNT_ENTRY(sock),
  47        SCTP_DBG_OBJCNT_ENTRY(ep),
  48        SCTP_DBG_OBJCNT_ENTRY(assoc),
  49        SCTP_DBG_OBJCNT_ENTRY(transport),
  50        SCTP_DBG_OBJCNT_ENTRY(chunk),
  51        SCTP_DBG_OBJCNT_ENTRY(bind_addr),
  52        SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
  53        SCTP_DBG_OBJCNT_ENTRY(addr),
  54        SCTP_DBG_OBJCNT_ENTRY(datamsg),
  55        SCTP_DBG_OBJCNT_ENTRY(keys),
  56};
  57
  58/* Callback from procfs to read out objcount information.
  59 * Walk through the entries in the sctp_dbg_objcnt array, dumping
  60 * the raw object counts for each monitored type.
  61 */
  62static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
  63{
  64        int i;
  65
  66        i = (int)*(loff_t *)v;
  67        seq_setwidth(seq, 127);
  68        seq_printf(seq, "%s: %d", sctp_dbg_objcnt[i].label,
  69                                atomic_read(sctp_dbg_objcnt[i].counter));
  70        seq_pad(seq, '\n');
  71        return 0;
  72}
  73
  74static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
  75{
  76        return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
  77}
  78
  79static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
  80{
  81}
  82
  83static void *sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  84{
  85        ++*pos;
  86        return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
  87}
  88
  89static const struct seq_operations sctp_objcnt_seq_ops = {
  90        .start = sctp_objcnt_seq_start,
  91        .next  = sctp_objcnt_seq_next,
  92        .stop  = sctp_objcnt_seq_stop,
  93        .show  = sctp_objcnt_seq_show,
  94};
  95
  96/* Initialize the objcount in the proc filesystem.  */
  97void sctp_dbg_objcnt_init(struct net *net)
  98{
  99        struct proc_dir_entry *ent;
 100
 101        ent = proc_create_seq("sctp_dbg_objcnt", 0,
 102                          net->sctp.proc_net_sctp, &sctp_objcnt_seq_ops);
 103        if (!ent)
 104                pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.\n");
 105}
 106