From 280981d6994e0700abd36647b141e73059851e66 Mon Sep 17 00:00:00 2001 From: Sathvika Vasireddy Date: Mon, 14 Nov 2022 23:27:49 +0530 Subject: objtool: Add --mnop as an option to --mcount Some architectures (powerpc) may not support ftrace locations being nop'ed out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as a means for architectures to enable nop'ing of ftrace locations. Add --mnop as an option to objtool --mcount, to indicate support for the same. Also, make sure that --mnop can be passed as an option to objtool only when --mcount is passed. Tested-by: Naveen N. Rao Reviewed-by: Naveen N. Rao Acked-by: Josh Poimboeuf Reviewed-by: Christophe Leroy Signed-off-by: Sathvika Vasireddy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221114175754.1131267-12-sv@linux.ibm.com --- tools/objtool/builtin-check.c | 14 ++++++++++++++ tools/objtool/check.c | 19 ++++++++++--------- tools/objtool/include/objtool/builtin.h | 1 + 3 files changed, 25 insertions(+), 9 deletions(-) (limited to 'tools/objtool') diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 24fbe803a0d3..9bd347d3c244 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -82,6 +82,7 @@ const struct option check_options[] = { OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"), OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"), OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"), + OPT_BOOLEAN(0, "mnop", &opts.mnop, "nop out mcount call sites"), OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"), OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"), OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"), @@ -150,6 +151,16 @@ static bool opts_valid(void) return false; } +static bool mnop_opts_valid(void) +{ + if (opts.mnop && !opts.mcount) { + ERROR("--mnop requires --mcount"); + return false; + } + + return true; +} + static bool link_opts_valid(struct objtool_file *file) { if (opts.link) @@ -198,6 +209,9 @@ int objtool_run(int argc, const char **argv) if (!file) return 1; + if (!mnop_opts_valid()) + return 1; + if (!link_opts_valid(file)) return 1; diff --git a/tools/objtool/check.c b/tools/objtool/check.c index b64518c7c7b4..71cf4b4ba1da 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1256,17 +1256,18 @@ static void annotate_call_site(struct objtool_file *file, if (opts.mcount && sym->fentry) { if (sibling) WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset); + if (opts.mnop) { + if (reloc) { + reloc->type = R_NONE; + elf_write_reloc(file->elf, reloc); + } - if (reloc) { - reloc->type = R_NONE; - elf_write_reloc(file->elf, reloc); - } - - elf_write_insn(file->elf, insn->sec, - insn->offset, insn->len, - arch_nop_insn(insn->len)); + elf_write_insn(file->elf, insn->sec, + insn->offset, insn->len, + arch_nop_insn(insn->len)); - insn->type = INSN_NOP; + insn->type = INSN_NOP; + } list_add_tail(&insn->call_node, &file->mcount_loc_list); return; diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 42a52f1a0add..0785707c5a92 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -31,6 +31,7 @@ struct opts { bool backup; bool dryrun; bool link; + bool mnop; bool module; bool no_unreachable; bool sec_address; -- cgit v1.2.3