mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
![Dave Chinner](/assets/img/avatar_default.png)
Running a CONFIG_XFS_DEBUG kernel in production environments is not the best idea as it introduces significant overhead, can change the behaviour of algorithms (such as allocation) to improve test coverage, and (most importantly) panic the machine on non-fatal errors. There are many cases where all we want to do is run a kernel with more bounds checking enabled, such as is provided by the ASSERT() statements throughout the code, but without all the potential overhead and drawbacks. This patch converts all the ASSERT statements to evaluate as WARN_ON(1) statements and hence if they fail dump a warning and a stack trace to the log. This has minimal overhead and does not change any algorithms, and will allow us to find strange "out of bounds" problems more easily on production machines. There are a few places where assert statements contain debug only code. These are converted to be debug-or-warn only code so that we still get all the assert checks in the code. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
90 lines
2.2 KiB
C
90 lines
2.2 KiB
C
/*
|
|
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
|
|
* All Rights Reserved.
|
|
*
|
|
* This program 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.
|
|
*
|
|
* This program is distributed in the hope that it would 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 this program; if not, write the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
#ifndef __XFS_SUPPORT_MRLOCK_H__
|
|
#define __XFS_SUPPORT_MRLOCK_H__
|
|
|
|
#include <linux/rwsem.h>
|
|
|
|
typedef struct {
|
|
struct rw_semaphore mr_lock;
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
int mr_writer;
|
|
#endif
|
|
} mrlock_t;
|
|
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
#define mrinit(mrp, name) \
|
|
do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0)
|
|
#else
|
|
#define mrinit(mrp, name) \
|
|
do { init_rwsem(&(mrp)->mr_lock); } while (0)
|
|
#endif
|
|
|
|
#define mrlock_init(mrp, t,n,s) mrinit(mrp, n)
|
|
#define mrfree(mrp) do { } while (0)
|
|
|
|
static inline void mraccess_nested(mrlock_t *mrp, int subclass)
|
|
{
|
|
down_read_nested(&mrp->mr_lock, subclass);
|
|
}
|
|
|
|
static inline void mrupdate_nested(mrlock_t *mrp, int subclass)
|
|
{
|
|
down_write_nested(&mrp->mr_lock, subclass);
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
mrp->mr_writer = 1;
|
|
#endif
|
|
}
|
|
|
|
static inline int mrtryaccess(mrlock_t *mrp)
|
|
{
|
|
return down_read_trylock(&mrp->mr_lock);
|
|
}
|
|
|
|
static inline int mrtryupdate(mrlock_t *mrp)
|
|
{
|
|
if (!down_write_trylock(&mrp->mr_lock))
|
|
return 0;
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
mrp->mr_writer = 1;
|
|
#endif
|
|
return 1;
|
|
}
|
|
|
|
static inline void mrunlock_excl(mrlock_t *mrp)
|
|
{
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
mrp->mr_writer = 0;
|
|
#endif
|
|
up_write(&mrp->mr_lock);
|
|
}
|
|
|
|
static inline void mrunlock_shared(mrlock_t *mrp)
|
|
{
|
|
up_read(&mrp->mr_lock);
|
|
}
|
|
|
|
static inline void mrdemote(mrlock_t *mrp)
|
|
{
|
|
#if defined(DEBUG) || defined(XFS_WARN)
|
|
mrp->mr_writer = 0;
|
|
#endif
|
|
downgrade_write(&mrp->mr_lock);
|
|
}
|
|
|
|
#endif /* __XFS_SUPPORT_MRLOCK_H__ */
|