/* 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, see
* .
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers
*
* Written or modified by:
* Jon Grimm
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include
#include
/*
* 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(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(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;
i = (int)*(loff_t *)v;
seq_setwidth(seq, 127);
seq_printf(seq, "%s: %d", sctp_dbg_objcnt[i].label,
atomic_read(sctp_dbg_objcnt[i].counter));
seq_pad(seq, '\n');
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(struct net *net)
{
struct proc_dir_entry *ent;
ent = proc_create("sctp_dbg_objcnt", 0,
net->sctp.proc_net_sctp, &sctp_objcnt_ops);
if (!ent)
pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.\n");
}
/* Cleanup the objcount entry in the proc filesystem. */
void sctp_dbg_objcnt_exit(struct net *net)
{
remove_proc_entry("sctp_dbg_objcnt", net->sctp.proc_net_sctp);
}
on value='1'>ignore
Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.
Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.
Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.
Reported-by: Erik Veijola <erik.veijola@intel.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>