Commit e2d9494b authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

objtool: Provide stats for jump_labels 



Add objtool --stats to count the jump_label sites it encounters.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210506194158.153101906@infradead.org
parent 6d37b83c

tools/objtool/check.c

+20 −2
Original line number Diff line number Diff line
@@ -1225,8 +1225,15 @@ static int handle_jump_alt(struct objtool_file *file, 
			   struct instruction *orig_insn,

			   struct instruction **new_insn)

{

	if (orig_insn->type == INSN_NOP)

	if (orig_insn->type == INSN_NOP) {

do_nop:

		if (orig_insn->len == 2)

			file->jl_nop_short++;

		else

			file->jl_nop_long++;



		return 0;

	}



	if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {

		WARN_FUNC("unsupported instruction at jump label",
@@ -1245,9 +1252,14 @@ static int handle_jump_alt(struct objtool_file *file, 
			       orig_insn->offset, orig_insn->len,

			       arch_nop_insn(orig_insn->len));

		orig_insn->type = INSN_NOP;

		return 0;

		goto do_nop;

	}



	if (orig_insn->len == 2)

		file->jl_short++;

	else

		file->jl_long++;



	*new_insn = list_next_entry(orig_insn, list);

	return 0;

}
@@ -1328,6 +1340,12 @@ static int add_special_section_alts(struct objtool_file *file) 
		free(special_alt);

	}



	if (stats) {

		printf("jl\\\tNOP\tJMP\n");

		printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);

		printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);

	}



out:

	return ret;

}

tools/objtool/include/objtool/objtool.h

+3 −0
Original line number Diff line number Diff line
@@ -22,6 +22,9 @@ struct objtool_file { 
	struct list_head static_call_list;

	struct list_head mcount_loc_list;

	bool ignore_unreachables, c_file, hints, rodata;



	unsigned long jl_short, jl_long;

	unsigned long jl_nop_short, jl_nop_long;

};



struct objtool_file *objtool_open_read(const char *_objname);