[RFC PATCH v6 08/34] dyndbg: accept null site in ddebug_match_site

Jim Cromie
2021-05-29T20:02:40Z

Since all query terms must be satisfied, we can reorder for clarity,
moving !!site dependent checks after those on _ddebug itself.

1- move format and line-number check code to the top of the function,
since they don't use/check site info.

2- test site pointer:
If its null, we return early, skipping 3:
If the query tests against missing site info, fail the match.
otherwize site matches.

3- rest of function (checking site vs query) is unchanged.

ddebug_match_site ignores module, because it's tested already
by the caller, where it is known from debug_tables.

no functional changes

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
lib/dynamic_debug.c | 41 +++++++++++++++++++++++++----------------
1 file changed, 25 insertions(+), 16 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 839dd128ba20..d62dc471bc1f 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -146,21 +146,7 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
static int ddebug_match_site(const struct ddebug_query *query,
const struct _ddebug *dp)
{
- struct _ddebug_site *dc = dp->site;
-
- /* match against the source filename */
- if (query->filename &&
- !match_wildcard(query->filename, dc->filename) &&
- !match_wildcard(query->filename,
- kbasename(dc->filename)) &&
- !match_wildcard(query->filename,
- trim_prefix(dc->filename)))
- return false;
-
- /* match against the function */
- if (query->function &&
- !match_wildcard(query->function, dc->function))
- return false;
+ struct _ddebug_site *dc;

/* match against the format */
if (query->format) {
@@ -182,6 +168,29 @@ static int ddebug_match_site(const struct ddebug_query *query,
dp->lineno > query->last_lineno)
return false;

+ dc = dp->site;
+ if (!dc) {
+ /* site info has been dropped, so query cannot test these fields */
+ if (query->filename || query->function)
+ return false;
+ else
+ return true;
+ }
+
+ /* match against the source filename */
+ if (query->filename &&
+ !match_wildcard(query->filename, dc->filename) &&
+ !match_wildcard(query->filename,
+ kbasename(dc->filename)) &&
+ !match_wildcard(query->filename,
+ trim_prefix(dc->filename)))
+ return false;
+
+ /* match against the function */
+ if (query->function &&
+ !match_wildcard(query->function, dc->function))
+ return false;
+
return true;
}

@@ -211,7 +220,7 @@ static int ddebug_change(const struct ddebug_query *query,

for (i = 0; i < dt->num_ddebugs; i++) {
struct _ddebug *dp = &dt->ddebugs[i];
- struct _ddebug_site *dc = dp->site;
+ struct _ddebug_site *dc;

if (!ddebug_match_site(query, dp))
continue;
--
2.31.1