linux-stable/net/sctp/objcnt.c
Pavel Emelyanov 5e659e4cb0 [NET]: Fix heavy stack usage in seq_file output routines.
Plan C: we can follow the Al Viro's proposal about %n like in this patch.
The same applies to udp, fib (the /proc/net/route file), rt_cache and 
sctp debug. This is minus ~150-200 bytes for each.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-24 01:02:16 -07:00

147 lines
4.2 KiB
C

/* SCTP kernel implementation
* (C) Copyright IBM Corp. 2001, 2004
*
* This file is part of the SCTP kernel implementation
*
* Support for memory object debugging. This allows one to monitor the
* object allocations/deallocations for types instrumented for this
* via the proc fs.
*
* This SCTP implementation is free software;
* you can redistribute it and/or modify it under the terms of
* the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This SCTP implementation is distributed in the hope that it
* will be useful, but WITHOUT ANY WARRANTY; without even the implied
* ************************
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU CC; see the file COPYING. If not, write to
* the Free Software Foundation, 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers <lksctp-developers@lists.sourceforge.net>
*
* Or submit a bug report through the following website:
* http://www.sf.net/projects/lksctp
*
* Written or modified by:
* Jon Grimm <jgrimm@us.ibm.com>
*
* Any bugs reported given to us we will try to fix... any fixes shared will
* be incorporated into the next SCTP release.
*/
#include <linux/kernel.h>
#include <net/sctp/sctp.h>
/*
* Global counters to count raw object allocation counts.
* To add new counters, choose a unique suffix for the variable
* name as the helper macros key off this suffix to make
* life easier for the programmer.
*/
SCTP_DBG_OBJCNT(sock);
SCTP_DBG_OBJCNT(ep);
SCTP_DBG_OBJCNT(transport);
SCTP_DBG_OBJCNT(assoc);
SCTP_DBG_OBJCNT(bind_addr);
SCTP_DBG_OBJCNT(bind_bucket);
SCTP_DBG_OBJCNT(chunk);
SCTP_DBG_OBJCNT(addr);
SCTP_DBG_OBJCNT(ssnmap);
SCTP_DBG_OBJCNT(datamsg);
SCTP_DBG_OBJCNT(keys);
/* An array to make it easy to pretty print the debug information
* to the proc fs.
*/
static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
SCTP_DBG_OBJCNT_ENTRY(sock),
SCTP_DBG_OBJCNT_ENTRY(ep),
SCTP_DBG_OBJCNT_ENTRY(assoc),
SCTP_DBG_OBJCNT_ENTRY(transport),
SCTP_DBG_OBJCNT_ENTRY(chunk),
SCTP_DBG_OBJCNT_ENTRY(bind_addr),
SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
SCTP_DBG_OBJCNT_ENTRY(addr),
SCTP_DBG_OBJCNT_ENTRY(ssnmap),
SCTP_DBG_OBJCNT_ENTRY(datamsg),
SCTP_DBG_OBJCNT_ENTRY(keys),
};
/* Callback from procfs to read out objcount information.
* Walk through the entries in the sctp_dbg_objcnt array, dumping
* the raw object counts for each monitored type.
*/
static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
{
int i, len;
i = (int)*(loff_t *)v;
seq_printf(seq, "%s: %d%n", sctp_dbg_objcnt[i].label,
atomic_read(sctp_dbg_objcnt[i].counter), &len);
seq_printf(seq, "%*s\n", 127 - len, "");
return 0;
}
static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
{
return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
}
static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
{
}
static void * sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
++*pos;
return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
}
static const struct seq_operations sctp_objcnt_seq_ops = {
.start = sctp_objcnt_seq_start,
.next = sctp_objcnt_seq_next,
.stop = sctp_objcnt_seq_stop,
.show = sctp_objcnt_seq_show,
};
static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
{
return seq_open(file, &sctp_objcnt_seq_ops);
}
static const struct file_operations sctp_objcnt_ops = {
.open = sctp_objcnt_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
/* Initialize the objcount in the proc filesystem. */
void sctp_dbg_objcnt_init(void)
{
struct proc_dir_entry *ent;
ent = proc_create("sctp_dbg_objcnt", 0,
proc_net_sctp, &sctp_objcnt_ops);
if (!ent)
printk(KERN_WARNING
"sctp_dbg_objcnt: Unable to create /proc entry.\n");
}
/* Cleanup the objcount entry in the proc filesystem. */
void sctp_dbg_objcnt_exit(void)
{
remove_proc_entry("sctp_dbg_objcnt", proc_net_sctp);
}