From 0a7fb6f07e3ad497d31ae9a2082d2cacab43d54a Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 14 Mar 2025 12:29:03 -0700 Subject: [PATCH] objtool: Increase per-function WARN_FUNC() rate limit 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 Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/aec318d66c037a51c9f376d6fb0e8ff32812a037.1741975349.git.jpoimboe@kernel.org --- 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 d6af5385baf6..2f64e46fe02d 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -4547,7 +4547,7 @@ 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, ...) \ -- 2.25.1