From 0a41e5d6849b4f705c377d34799485b546764970 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 18 Mar 2024 22:51:04 -0700 Subject: [PATCH] perf annotate-data: Handle global variable access When updating the instruction states, it also needs to handle global variable accesses. Same as it does for PC-relative addressing, it can look up the type by address (if it's defined in the same file), or by name after finding the symbol by address (for declarations). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240319055115.4063940-13-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/annotate-data.c | 46 ++++++++++++++++++++++++++++++--- 1 file changed, 42 insertions(+), 4 deletions(-) diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c index 3b661e693410..2cc9f56e3eea 100644 --- a/tools/perf/util/annotate-data.c +++ b/tools/perf/util/annotate-data.c @@ -89,7 +89,7 @@ void exit_type_state(struct type_state *state); void update_var_state(struct type_state *state, struct data_loc_info *dloc, u64 addr, u64 insn_offset, struct die_var_type *var_types); void update_insn_state(struct type_state *state, struct data_loc_info *dloc, - struct disasm_line *dl); + Dwarf_Die *cu_die, struct disasm_line *dl); void init_type_state(struct type_state *state, struct arch *arch __maybe_unused) { @@ -485,7 +485,7 @@ void update_var_state(struct type_state *state, struct data_loc_info *dloc, } static void update_insn_state_x86(struct type_state *state, - struct data_loc_info *dloc, + struct data_loc_info *dloc, Dwarf_Die *cu_die, struct disasm_line *dl) { struct annotated_insn_loc loc; @@ -577,6 +577,29 @@ retry: insn_offset, src->offset, sreg, dst->reg1); pr_debug_type_name(&tsr->type); } + /* Or check if it's a global variable */ + else if (sreg == DWARF_REG_PC) { + struct map_symbol *ms = dloc->ms; + u64 ip = ms->sym->start + dl->al.offset; + u64 addr; + int offset; + + addr = annotate_calc_pcrel(ms, ip, src->offset, dl); + + if (!get_global_var_type(cu_die, dloc, ip, addr, &offset, + &type_die) || + !die_get_member_type(&type_die, offset, &type_die)) { + tsr->ok = false; + return; + } + + tsr->type = type_die; + tsr->ok = true; + + pr_debug_dtp("mov [%x] global addr=%"PRIx64" -> reg%d", + insn_offset, addr, dst->reg1); + pr_debug_type_name(&type_die); + } /* Or try another register if any */ else if (src->multi_regs && sreg == src->reg1 && src->reg1 != src->reg2) { @@ -628,11 +651,26 @@ retry: /* Case 4. memory to memory transfers (not handled for now) */ } +/** + * update_insn_state - Update type state for an instruction + * @state: type state table + * @dloc: data location info + * @cu_die: compile unit debug entry + * @dl: disasm line for the instruction + * + * This function updates the @state table for the target operand of the + * instruction at @dl if it transfers the type like MOV on x86. Since it + * tracks the type, it won't care about the values like in arithmetic + * instructions like ADD/SUB/MUL/DIV and INC/DEC. + * + * Note that ops->reg2 is only available when both mem_ref and multi_regs + * are true. + */ void update_insn_state(struct type_state *state, struct data_loc_info *dloc, - struct disasm_line *dl) + Dwarf_Die *cu_die, struct disasm_line *dl) { if (arch__is(dloc->arch, "x86")) - update_insn_state_x86(state, dloc, dl); + update_insn_state_x86(state, dloc, cu_die, dl); } /* The result will be saved in @type_die */