[PATCH 18/25] dynamic_debug: describe_flags with '=[pmflta_]*'

[Jim Cromie <jim.cromie@gmail.com>]

Change describe_flags() to emit '=[pmflta_]+' for current callsite
flags, or just '=_' when they're disabled.  Having '=' in output
allows a more selective grep expression, in contrast '-' may appear
in filenames, line-ranges, and format-strings.  '=' also has better
mnemonics, saying; "the current setting are equal to <flags>".

The default allows grep "=_" <dbgfs>/dynamic_debug/control
to see disabled callsites while avoiding the many occurrences of " = "
seen in format strings.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
 lib/dynamic_debug.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 396ffb4..37f9748 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -92,6 +92,7 @@ static struct { unsigned flag:8; char opt_char; } opt_array[] = {
 	{ _DPRINTK_FLAGS_INCL_LINENO, 'l' },
 	{ _DPRINTK_FLAGS_INCL_TID, 't' },
 	{ _DPRINTK_FLAGS_APPEND, 'a' },
+	{ _DPRINTK_FLAGS_DEFAULT, '_' },
 };
 
 /* format a string into buf[] which describes the _ddebug's flags */
@@ -102,11 +103,12 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
 	int i;
 
 	BUG_ON(maxlen < 4);
+	*p++ = '=';
 	for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
 		if (dp->flags & opt_array[i].flag)
 			*p++ = opt_array[i].opt_char;
-	if (p == buf)
-		*p++ = '-';
+	if (*(p-1) == '=')
+		*p++ = '_';
 	*p = '\0';
 
 	return buf;
-- 
1.7.4.1