xref: /linux/net/sctp/objcnt.c (revision fcc8487d477a3452a1d0ccbdd4c5e0e1e3cb8bed)
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 
46 SCTP_DBG_OBJCNT(sock);
47 SCTP_DBG_OBJCNT(ep);
48 SCTP_DBG_OBJCNT(transport);
49 SCTP_DBG_OBJCNT(assoc);
50 SCTP_DBG_OBJCNT(bind_addr);
51 SCTP_DBG_OBJCNT(bind_bucket);
52 SCTP_DBG_OBJCNT(chunk);
53 SCTP_DBG_OBJCNT(addr);
54 SCTP_DBG_OBJCNT(datamsg);
55 SCTP_DBG_OBJCNT(keys);
56 
57 /* An array to make it easy to pretty print the debug information
58  * to the proc fs.
59  */
60 static 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  */
77 static 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 
89 static 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 
94 static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
95 {
96 }
97 
98 static 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 
104 static 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 
111 static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
112 {
113 	return seq_open(file, &sctp_objcnt_seq_ops);
114 }
115 
116 static 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.  */
124 void 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.  */
135 void sctp_dbg_objcnt_exit(struct net *net)
136 {
137 	remove_proc_entry("sctp_dbg_objcnt", net->sctp.proc_net_sctp);
138 }
139 
140 
141