[PATCH 01/17] dyndbg: factor ddebug_match_desc out from ddebug_change
From: Jim Cromie <jim.cromie@gmail.com>
Date: 2026-05-04 20:45:17
Also in:
linux-modules, lkml
Subsystem:
dynamic debug, library code, the rest · Maintainers:
Jason Baron, Jim Cromie, Andrew Morton, Linus Torvalds
ddebug_change() is a big (~100 lines) function with a nested for loop. The outer loop walks the per-module ddebug_tables list, and does module stuff: it filters on a query's "module FOO*" and "class BAR", failures here skip the entire inner loop. The inner loop (60 lines) scans a module's descriptors. It starts with a long block of filters on function, line, format, and the validated "BAR" class (or the legacy/_DPRINTK_CLASS_DFLT). These filters "continue" past pr_debugs that don't match the query criteria, before it falls through the code below that counts matches, then adjusts the flags and static-keys. This is unnecessarily hard to think about. So move the per-descriptor filter-block into a boolean function: ddebug_match_desc(desc), and change each "continue" to "return false". This puts a clear interface in place, so any future changes are either inside, outside, or across this interface. also fix checkpatch complaints about spaces and braces. Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 83 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 47 insertions(+), 36 deletions(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 18a71a9108d3..6b1e983cfedc 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c@@ -172,6 +172,52 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons * callsites, normally the same as number of changes. If verbose, * logs the changes. Takes ddebug_lock. */ +static bool ddebug_match_desc(const struct ddebug_query *query, + struct _ddebug *dp, + int valid_class) +{ + /* match site against query-class */ + if (dp->class_id != valid_class) + return false; + + /* match against the source filename */ + if (query->filename && + !match_wildcard(query->filename, dp->filename) && + !match_wildcard(query->filename, + kbasename(dp->filename)) && + !match_wildcard(query->filename, + trim_prefix(dp->filename))) + return false; + + /* match against the function */ + if (query->function && + !match_wildcard(query->function, dp->function)) + return false; + + /* match against the format */ + if (query->format) { + if (*query->format == '^') { + char *p; + /* anchored search. match must be at beginning */ + p = strstr(dp->format, query->format + 1); + if (p != dp->format) + return false; + } else if (!strstr(dp->format, query->format)) { + return false; + } + } + + /* match against the line number range */ + if (query->first_lineno && + dp->lineno < query->first_lineno) + return false; + if (query->last_lineno && + dp->lineno > query->last_lineno) + return false; + + return true; +} + static int ddebug_change(const struct ddebug_query *query, struct flag_settings *modifiers) {
@@ -204,42 +250,7 @@ static int ddebug_change(const struct ddebug_query *query, for (i = 0; i < dt->num_ddebugs; i++) { struct _ddebug *dp = &dt->ddebugs[i]; - /* match site against query-class */ - if (dp->class_id != valid_class) - continue; - - /* match against the source filename */ - if (query->filename && - !match_wildcard(query->filename, dp->filename) && - !match_wildcard(query->filename, - kbasename(dp->filename)) && - !match_wildcard(query->filename, - trim_prefix(dp->filename))) - continue; - - /* match against the function */ - if (query->function && - !match_wildcard(query->function, dp->function)) - continue; - - /* match against the format */ - if (query->format) { - if (*query->format == '^') { - char *p; - /* anchored search. match must be at beginning */ - p = strstr(dp->format, query->format+1); - if (p != dp->format) - continue; - } else if (!strstr(dp->format, query->format)) - continue; - } - - /* match against the line number range */ - if (query->first_lineno && - dp->lineno < query->first_lineno) - continue; - if (query->last_lineno && - dp->lineno > query->last_lineno) + if (!ddebug_match_desc(query, dp, valid_class)) continue; nfound++;
--
2.54.0