diff --git a/include/sys/sdt.h b/include/sys/sdt.h
index 56efa1b39..9704072cb 100644
--- a/include/sys/sdt.h
+++ b/include/sys/sdt.h
@@ -34,13 +34,8 @@
 #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)
-#define	ZFS_SET_ERROR(err)		((void) 0)
 
-#else
-
-#if defined(HAVE_DECLARE_EVENT_CLASS)
-
-#include <sys/trace.h>
+#endif /* _KERNEL */
 
 /*
  * The set-error SDT probe is extra static, in that we declare its fake
@@ -55,16 +50,9 @@
  * twice, so it should not have side effects (e.g. something like:
  * "return (SET_ERROR(log_error(EINVAL, info)));" would log the error twice).
  */
-#define	SET_ERROR(err) \
-	(trace_zfs_set__error(__FILE__, __func__, __LINE__, err), err)
-
-#else
-
+extern void __set_error(const char *file, const char *func, int line, int err);
 #undef SET_ERROR
-#define	SET_ERROR(err) (err)
-
-#endif /* HAVE_DECLARE_EVENT_CLASS */
-
-#endif /* _KERNEL */
+#define	SET_ERROR(err) \
+	(__set_error(__FILE__, __func__, __LINE__, err), err)
 
 #endif /* _SYS_SDT_H */
diff --git a/include/sys/trace_dbgmsg.h b/include/sys/trace_dbgmsg.h
index 08d96c59c..a4aab1e63 100644
--- a/include/sys/trace_dbgmsg.h
+++ b/include/sys/trace_dbgmsg.h
@@ -37,92 +37,29 @@
  */
 
 /*
- * Generic support for four argument tracepoints of the form:
+ * Generic support for one argument tracepoints of the form:
  *
- * DTRACE_PROBE4(...,
- *     const char *, ...,
- *     const char *, ...,
- *     int, ...,
+ * DTRACE_PROBE1(...,
  *     const char *, ...);
  */
 /* BEGIN CSTYLED */
 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_PROTO(const char *msg),
+	TP_ARGS(msg),
 	TP_STRUCT__entry(
-	    __string(file, file)
-	    __string(function, function)
-	    __field(int,		line)
 	    __string(msg, msg)
 	),
 	TP_fast_assign(
-	    __assign_str(file, strchr(file, '/') ?
-		strrchr(file, '/') + 1 : file)
-	    __assign_str(function, function);
-	    __entry->line		= line;
 	    __assign_str(msg, msg);
 	),
-	TP_printk("%s:%d:%s(): %s", __get_str(file), __entry->line,
-	    __get_str(function), __get_str(msg))
+	TP_printk("%s", __get_str(msg))
 );
 /* END CSTYLED */
 
 /* BEGIN CSTYLED */
 #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))
+	TP_PROTO(const char *msg), \
+	TP_ARGS(msg))
 /* END CSTYLED */
 DEFINE_DPRINTF_EVENT(zfs_zfs__dprintf);
-
-/*
- * Generic support for four argument tracepoints of the form:
- *
- * DTRACE_PROBE4(...,
- *     const char *, ...,
- *     const char *, ...,
- *     int, ...,
- *     uintptr_t, ...);
- */
-/* BEGIN CSTYLED */
-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(
-	    __string(file, file)
-	    __string(function, function)
-	    __field(int,		line)
-	    __field(uintptr_t,		error)
-	),
-	TP_fast_assign(
-	    __assign_str(file, strchr(file, '/') ?
-		strrchr(file, '/') + 1 : file)
-	    __assign_str(function, function);
-	    __entry->line		= line;
-	    __entry->error		= error;
-	),
-	TP_printk("%s:%d:%s(): error 0x%lx", __get_str(file), __entry->line,
-	    __get_str(function), __entry->error)
-);
-/* END CSTYLED */
-
-/* BEGIN CSTYLED */
-#ifdef TP_CONDITION
-#define	DEFINE_SET_ERROR_EVENT(name) \
-DEFINE_EVENT_CONDITION(zfs_set_error_class, name, \
-	TP_PROTO(const char *file, const char *function, int line, \
-	    uintptr_t error), \
-	TP_ARGS(file, function, line, error), \
-	TP_CONDITION(error))
-#else
-#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))
-#endif
-/* END CSTYLED */
-DEFINE_SET_ERROR_EVENT(zfs_set__error);
diff --git a/include/sys/zfs_context.h b/include/sys/zfs_context.h
index 6163b2fbf..4fe35342d 100644
--- a/include/sys/zfs_context.h
+++ b/include/sys/zfs_context.h
@@ -206,15 +206,6 @@ extern int aok;
 	ZFS_PROBE4(#a, (unsigned long)c, (unsigned long)e, (unsigned long)g, \
 	(unsigned long)i)
 
-/*
- * We use the comma operator so that this macro 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).
- */
-#define	SET_ERROR(err) (ZFS_SET_ERROR(err), err)
-
 /*
  * Threads.  TS_STACK_MIN is dictated by the minimum allowed pthread stack
  * size.  While TS_STACK_MAX is somewhat arbitrary, it was selected to be
diff --git a/include/sys/zfs_debug.h b/include/sys/zfs_debug.h
index b9b06a5ad..226aaa2b8 100644
--- a/include/sys/zfs_debug.h
+++ b/include/sys/zfs_debug.h
@@ -51,6 +51,7 @@ extern int zfs_free_leak_on_eio;
 #define	ZFS_DEBUG_ZIO_FREE		(1 << 6)
 #define	ZFS_DEBUG_HISTOGRAM_VERIFY	(1 << 7)
 #define	ZFS_DEBUG_METASLAB_VERIFY	(1 << 8)
+#define	ZFS_DEBUG_SET_ERROR		(1 << 9)
 
 extern void __dprintf(const char *file, const char *func,
     int line, const char *fmt, ...);
diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5
index 0447debf7..f7bb2eb8c 100644
--- a/man/man5/zfs-module-parameters.5
+++ b/man/man5/zfs-module-parameters.5
@@ -1258,6 +1258,12 @@ _
 _
 128	ZFS_DEBUG_HISTOGRAM_VERIFY
 	Enable extra spacemap histogram verifications.
+_
+256	ZFS_DEBUG_METASLAB_VERIFY
+	Verify space accounting on disk matches in-core range_trees.
+_
+512	ZFS_DEBUG_SET_ERROR
+	Enable SET_ERROR and dprintf entries in the debug log.
 .TE
 .sp
 * Requires debug build.
diff --git a/module/zfs/zfs_debug.c b/module/zfs/zfs_debug.c
index 90c1d7361..d1dba3f8f 100644
--- a/module/zfs/zfs_debug.c
+++ b/module/zfs/zfs_debug.c
@@ -161,6 +161,13 @@ __zfs_dbgmsg(char *buf)
 	mutex_exit(&zfs_dbgmsgs_lock);
 }
 
+void
+__set_error(const char *file, const char *func, int line, int err)
+{
+	if (zfs_flags & ZFS_DEBUG_SET_ERROR)
+		__dprintf(file, func, line, "error %lu", err);
+}
+
 #ifdef _KERNEL
 void
 __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
@@ -170,8 +177,10 @@ __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
 	size_t size;
 	char *buf;
 	char *nl;
+	int i;
 
-	if (!zfs_dbgmsg_enable && !(zfs_flags & ZFS_DEBUG_DPRINTF))
+	if (!zfs_dbgmsg_enable &&
+	    !(zfs_flags & (ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SET_ERROR)))
 		return;
 
 	size = 1024;
@@ -187,9 +196,13 @@ __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
 		newfile = file;
 	}
 
-	va_start(adx, fmt);
-	(void) vsnprintf(buf, size, fmt, adx);
-	va_end(adx);
+	i = snprintf(buf, size, "%s:%d:%s(): ", newfile, line, func);
+
+	if (i < size) {
+		va_start(adx, fmt);
+		(void) vsnprintf(buf + i, size - i, fmt, adx);
+		va_end(adx);
+	}
 
 	/*
 	 * Get rid of trailing newline.
@@ -209,9 +222,8 @@ __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
 	 * # Dump the ring buffer.
 	 * $ cat /sys/kernel/debug/tracing/trace
 	 */
-	if (zfs_flags & ZFS_DEBUG_DPRINTF)
-		DTRACE_PROBE4(zfs__dprintf,
-		    char *, newfile, char *, func, int, line, char *, buf);
+	if (zfs_flags & (ZFS_DEBUG_DPRINTF | ZFS_DEBUG_SET_ERROR))
+		DTRACE_PROBE1(zfs__dprintf, char *, buf);
 
 	/*
 	 * To get this data enable the zfs debug log as shown: