freebsd-dev/include/sys/sdt.h
Ned Bass 8740cf4a2f Add line info and SET_ERROR() to ZFS debug log
Redefine the SET_ERROR macro in terms of __dprintf() so the error
return codes get logged as both tracepoint events (if tracepoints are
enabled) and as ZFS debug log entries.  This also allows us to use
the same definition of SET_ERROR() in kernel and user space.

Define a new debug flag ZFS_DEBUG_SET_ERROR=512 that may be bitwise
or'd into zfs_flags. Setting this flag enables both dprintf() and
SET_ERROR() messages in the debug log. That is, setting
ZFS_DEBUG_SET_ERROR and ZFS_DEBUG_DPRINTF|ZFS_DEBUG_SET_ERROR are
equivalent (this was done for sake of simplicity). Leaving
ZFS_DEBUG_SET_ERROR unset suppresses the SET_ERROR() messages which
helps avoid cluttering up the logs.

To enable SET_ERROR() logging, run:

  echo 1 >   /sys/module/zfs/parameters/zfs_dbgmsg_enable
  echo 512 > /sys/module/zfs/parameters/zfs_flags

Remove the zfs_set_error_class tracepoints event class since
SET_ERROR() now uses __dprintf(). This sacrifices a bit of
granularity when selecting individual tracepoint events to enable but
it makes the code simpler.

Include file, function, and line number information in debug log
entries.  The information is now added to the message buffer in
__dprintf() and as a result the zfs_dprintf_class tracepoints event
class was changed from a 4 parameter interface to a single parameter.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #6400
2017-07-25 23:09:48 -07:00

59 lines
2.1 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_SDT_H
#define _SYS_SDT_H
#ifndef _KERNEL
#define ZFS_PROBE(a) ((void) 0)
#define ZFS_PROBE1(a, c) ((void) 0)
#define ZFS_PROBE2(a, c, e) ((void) 0)
#define ZFS_PROBE3(a, c, e, g) ((void) 0)
#define ZFS_PROBE4(a, c, e, g, i) ((void) 0)
#endif /* _KERNEL */
/*
* The set-error SDT probe is extra static, in that we declare its fake
* function literally, rather than with the DTRACE_PROBE1() macro. This is
* necessary so that SET_ERROR() can evaluate to a value, which wouldn't
* be possible if it required multiple statements (to declare the function
* and then call it).
*
* SET_ERROR() uses the comma operator so that it can be used without much
* additional code. For example, "return (EINVAL);" becomes
* "return (SET_ERROR(EINVAL));". Note that the argument will be evaluated
* twice, so it should not have side effects (e.g. something like:
* "return (SET_ERROR(log_error(EINVAL, info)));" would log the error twice).
*/
extern void __set_error(const char *file, const char *func, int line, int err);
#undef SET_ERROR
#define SET_ERROR(err) \
(__set_error(__FILE__, __func__, __LINE__, err), err)
#endif /* _SYS_SDT_H */