mirror_zfs/include/sys/trace_dbgmsg.h
Brian Behlendorf 3b36f8319d Add dbgmsg kstat
Internally ZFS keeps a small log to facilitate debugging.  By default
the log is disabled, to enable it set zfs_dbgmsg_enable=1.  The contents
of the log can be accessed by reading the /proc/spl/kstat/zfs/dbgmsg file.
Writing 0 to this proc file clears the log.

$ echo 1 >/sys/module/zfs/parameters/zfs_dbgmsg_enable
$ echo 0 >/proc/spl/kstat/zfs/dbgmsg
$ zpool import tank
$ cat /proc/spl/kstat/zfs/dbgmsg
1 0 0x01 -1 0 2492357525542 2525836565501
timestamp    message
1441141408   spa=tank async request task=1
1441141408   txg 70 open pool version 5000; software version 5000/5; ...
1441141409   spa=tank async request task=32
1441141409   txg 72 import pool version 5000; software version 5000/5; ...
1441141414   command: lt-zpool import tank

Note the zfs_dbgmsg() and dprintf() functions are both now mapped to
the same log.  As mentioned above the kernel debug log can be accessed
though the /proc/spl/kstat/zfs/dbgmsg kstat.  For user space consumers
log messages are immediately written to stdout after applying the
ZFS_DEBUG environment variable.

$ ZFS_DEBUG=on ./cmd/ztest/ztest -V

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #3728
2015-09-04 16:08:14 -07:00

112 lines
3.4 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (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
*/
/* Do not include this file directly. Please use <sys/trace.h> instead. */
#ifndef _SYS_TRACE_DBGMSG_INDIRECT
#error "trace_dbgmsg.h included directly"
#endif
/*
* This file defines tracepoint events for use by the dbgmsg(),
* dprintf(), and SET_ERROR() interfaces. These are grouped here because
* they all provide a way to store simple messages in the debug log (as
* opposed to events used by the DTRACE_PROBE interfaces which typically
* dump structured data).
*
* This header is included inside the trace.h multiple inclusion guard,
* and it is guarded above against direct inclusion, so it and need not
* be guarded separately.
*/
/*
* Generic support for four argument tracepoints of the form:
*
* DTRACE_PROBE4(...,
* const char *, ...,
* const char *, ...,
* int, ...,
* const char *, ...);
*/
DECLARE_EVENT_CLASS(zfs_dprintf_class,
TP_PROTO(const char *file, const char *function, int line,
const char *msg),
TP_ARGS(file, function, line, msg),
TP_STRUCT__entry(
__field(const char *, file)
__field(const char *, function)
__field(int, line)
__string(msg, msg)
),
TP_fast_assign(
__entry->file = file;
__entry->function = function;
__entry->line = line;
__assign_str(msg, msg);
),
TP_printk("%s:%d:%s(): %s", __entry->file, __entry->line,
__entry->function, __get_str(msg))
);
#define DEFINE_DPRINTF_EVENT(name) \
DEFINE_EVENT(zfs_dprintf_class, name, \
TP_PROTO(const char *file, const char *function, int line, \
const char *msg), \
TP_ARGS(file, function, line, msg))
DEFINE_DPRINTF_EVENT(zfs_zfs__dprintf);
/*
* Generic support for four argument tracepoints of the form:
*
* DTRACE_PROBE4(...,
* const char *, ...,
* const char *, ...,
* int, ...,
* uintptr_t, ...);
*/
DECLARE_EVENT_CLASS(zfs_set_error_class,
TP_PROTO(const char *file, const char *function, int line,
uintptr_t error),
TP_ARGS(file, function, line, error),
TP_STRUCT__entry(
__field(const char *, file)
__field(const char *, function)
__field(int, line)
__field(uintptr_t, error)
),
TP_fast_assign(
__entry->file = strchr(file, '/') ? strrchr(file, '/') + 1 : file;
__entry->function = function;
__entry->line = line;
__entry->error = error;
),
TP_printk("%s:%d:%s(): error 0x%lx", __entry->file, __entry->line,
__entry->function, __entry->error)
);
#define DEFINE_SET_ERROR_EVENT(name) \
DEFINE_EVENT(zfs_set_error_class, name, \
TP_PROTO(const char *file, const char *function, int line, \
uintptr_t error), \
TP_ARGS(file, function, line, error))
DEFINE_SET_ERROR_EVENT(zfs_set__error);