[PATCH 05/13] objtool: Increase per-function WARN_FUNC() rate limit
From: Josh Poimboeuf
Date: Fri Mar 14 2025 - 15:32:43 EST
Increase the per-function WARN_FUNC() rate limit from 1 to 2. If the
number of warnings for a given function goes beyond 2, print "skipping
duplicate warning(s)". This helps root out additional warnings in a
function that might be hiding behind the first one.
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
tools/objtool/check.c | 2 +-
tools/objtool/include/objtool/elf.h | 2 +-
tools/objtool/include/objtool/warn.h | 14 +++++++++++---
3 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 6b9ad3afe389..3ddaefe97f55 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -4528,7 +4528,7 @@ static int disas_warned_funcs(struct objtool_file *file)
char *funcs = NULL, *tmp;
for_each_sym(file, sym) {
- if (sym->warned) {
+ if (sym->warnings) {
if (!funcs) {
funcs = malloc(strlen(sym->name) + 1);
strcpy(funcs, sym->name);
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index d7e815c2fd15..223ac1c24b90 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -65,10 +65,10 @@ struct symbol {
u8 return_thunk : 1;
u8 fentry : 1;
u8 profiling_func : 1;
- u8 warned : 1;
u8 embedded_insn : 1;
u8 local_label : 1;
u8 frame_pointer : 1;
+ u8 warnings : 2;
struct list_head pv_target;
struct reloc *relocs;
};
diff --git a/tools/objtool/include/objtool/warn.h b/tools/objtool/include/objtool/warn.h
index ac04d3fe4dd9..6180288927fd 100644
--- a/tools/objtool/include/objtool/warn.h
+++ b/tools/objtool/include/objtool/warn.h
@@ -53,14 +53,22 @@ static inline char *offstr(struct section *sec, unsigned long offset)
free(_str); \
})
+#define WARN_LIMIT 2
+
#define WARN_INSN(insn, format, ...) \
({ \
struct instruction *_insn = (insn); \
- if (!_insn->sym || !_insn->sym->warned) \
+ BUILD_BUG_ON(WARN_LIMIT > 2); \
+ if (!_insn->sym || _insn->sym->warnings < WARN_LIMIT) { \
WARN_FUNC(format, _insn->sec, _insn->offset, \
##__VA_ARGS__); \
- if (_insn->sym) \
- _insn->sym->warned = 1; \
+ if (_insn->sym) \
+ _insn->sym->warnings++; \
+ } else if (_insn->sym && _insn->sym->warnings == WARN_LIMIT) { \
+ WARN_FUNC("skipping duplicate warning(s)", \
+ _insn->sec, _insn->offset); \
+ _insn->sym->warnings++; \
+ } \
})
#define BT_INSN(insn, format, ...) \
--
2.48.1