dynamic_debug: describe_flags with '=[pmflt_]*'

Change describe_flags() to emit '=[pmflt_]+' 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 is equal to <flags>".

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

Enlarge flagsbufs to handle additional flag char, and alter
ddebug_parse_flags() to allow flags=0, so that user can turn off all
debug flags via:

  ~# echo =_ > <dbgfs>/dynamic_debug/control

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jim Cromie 2011-12-19 17:12:44 -05:00 committed by Greg Kroah-Hartman
parent d6a238d250
commit 5ca7d2a6c5
2 changed files with 12 additions and 12 deletions

View File

@ -21,7 +21,8 @@ struct _ddebug {
* The bits here are changed dynamically when the user
* writes commands to <debugfs>/dynamic_debug/control
*/
#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
#define _DPRINTK_FLAGS_NONE 0
#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
#define _DPRINTK_FLAGS_INCL_MODNAME (1<<1)
#define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2)
#define _DPRINTK_FLAGS_INCL_LINENO (1<<3)

View File

@ -75,6 +75,7 @@ static struct { unsigned flag:8; char opt_char; } opt_array[] = {
{ _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
{ _DPRINTK_FLAGS_INCL_LINENO, 'l' },
{ _DPRINTK_FLAGS_INCL_TID, 't' },
{ _DPRINTK_FLAGS_NONE, '_' },
};
/* format a string into buf[] which describes the _ddebug's flags */
@ -84,12 +85,12 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
char *p = buf;
int i;
BUG_ON(maxlen < 4);
BUG_ON(maxlen < 6);
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++ = '-';
*p++ = '_';
*p = '\0';
return buf;
@ -108,7 +109,7 @@ static void ddebug_change(const struct ddebug_query *query,
struct ddebug_table *dt;
unsigned int newflags;
unsigned int nfound = 0;
char flagbuf[8];
char flagbuf[10];
/* search for matching ddebugs */
mutex_lock(&ddebug_lock);
@ -152,7 +153,7 @@ static void ddebug_change(const struct ddebug_query *query,
continue;
dp->flags = newflags;
if (verbose)
pr_info("changed %s:%d [%s]%s %s\n",
pr_info("changed %s:%d [%s]%s =%s\n",
dp->filename, dp->lineno,
dt->mod_name, dp->function,
ddebug_describe_flags(dp, flagbuf,
@ -370,8 +371,6 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
if (i < 0)
return -EINVAL;
}
if (flags == 0)
return -EINVAL;
if (verbose)
pr_info("flags=0x%x\n", flags);
@ -666,7 +665,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
{
struct ddebug_iter *iter = m->private;
struct _ddebug *dp = p;
char flagsbuf[8];
char flagsbuf[10];
if (verbose)
pr_info("called m=%p p=%p\n", m, p);
@ -677,10 +676,10 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
return 0;
}
seq_printf(m, "%s:%u [%s]%s %s \"",
dp->filename, dp->lineno,
iter->table->mod_name, dp->function,
ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf)));
seq_printf(m, "%s:%u [%s]%s =%s \"",
dp->filename, dp->lineno,
iter->table->mod_name, dp->function,
ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf)));
seq_escape(m, dp->format, "\t\r\n\"");
seq_puts(m, "\"\n");