@@ -1169,6 +1169,40 @@ static int find_data_type_block(struct data_loc_info *dloc,
return ret;
}
+/*
+ * Handle cases where define a global register variable and
+ * associate it with a specified register. These regs are
+ * present in dwarf debug as DW_OP_reg as part of variables
+ * in the cu_die (compile unit). Iterate over variables in the
+ * cu_die and match with reg to identify data type die.
+ */
+static int find_data_type_global_reg(struct data_loc_info *dloc, int reg, Dwarf_Die *cu_die,
+ Dwarf_Die *type_die)
+{
+ Dwarf_Die vr_die;
+ int ret = -1;
+ struct die_var_type *var_types = NULL;
+
+ die_collect_vars(cu_die, &var_types);
+ while (var_types) {
+ if (var_types->reg == reg) {
+ if (dwarf_offdie(dloc->di->dbg, var_types->die_off, &vr_die)) {
+ if (die_get_real_type(&vr_die, type_die) == NULL) {
+ dloc->type_offset = 0;
+ dwarf_offdie(dloc->di->dbg, var_types->die_off, type_die);
+ }
+ pr_debug_type_name(type_die, TSR_KIND_TYPE);
+ ret = 0;
+ pr_debug_dtp("found by CU for %s (die:%#lx)\n",
+ dwarf_diename(type_die), (long)dwarf_dieoffset(type_die));
+ }
+ break;
+ }
+ var_types = var_types->next;
+ }
+ return ret;
+}
+
/* The result will be saved in @type_die */
static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
{
@@ -1216,6 +1250,12 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
pr_debug_dtp("CU for %s (die:%#lx)\n",
dwarf_diename(&cu_die), (long)dwarf_dieoffset(&cu_die));
+ if (loc->reg_type == DWARF_REG_GLOBAL) {
+ ret = find_data_type_global_reg(dloc, reg, &cu_die, type_die);
+ if (!ret)
+ goto out;
+ }
+
if (reg == DWARF_REG_PC) {
if (get_global_var_type(&cu_die, dloc, dloc->ip, dloc->var_addr,
&offset, type_die)) {
@@ -2426,6 +2426,14 @@ struct annotated_data_type *hist_entry__get_data_type(struct hist_entry *he)
op_loc->reg1 = DWARF_REG_PC;
}
+ /* Global reg variable 13 and 1
+ * assign to DWARF_REG_GLOBAL
+ */
+ if (arch__is(arch, "powerpc")) {
+ if ((op_loc->reg1 == 13) || (op_loc->reg1 == 1))
+ op_loc->reg_type = DWARF_REG_GLOBAL;
+ }
+
mem_type = find_data_type(&dloc);
if (mem_type == NULL && is_stack_canary(arch, op_loc)) {
@@ -472,6 +472,7 @@ struct annotated_op_loc {
bool mem_ref;
bool multi_regs;
bool imm;
+ int reg_type;
};
enum annotated_insn_ops {
@@ -5,6 +5,7 @@
#define DWARF_REG_PC 0xd3af9c /* random number */
#define DWARF_REG_FB 0xd3affb /* random number */
+#define DWARF_REG_GLOBAL 0xd3affc /* random number */
#ifdef HAVE_DWARF_SUPPORT
const char *get_arch_regstr(unsigned int n);
There are cases where define a global register variable and associate it with a specified register. Example, in powerpc, two registers are defined to represent variable: 1. r13: represents local_paca register struct paca_struct *local_paca asm("r13"); 2. r1: represents stack_pointer register void *__stack_pointer asm("r1"); These regs are present in dwarf debug as DW_OP_reg as part of variables in the cu_die (compile unit). These are not present in die search done in the list of nested scopes since these are global register variables. Example for local_paca represented by r13: <<>> <1><18dc6b4>: Abbrev Number: 128 (DW_TAG_variable) <18dc6b6> DW_AT_name : (indirect string, offset: 0x3861): local_paca <18dc6ba> DW_AT_decl_file : 48 <18dc6bb> DW_AT_decl_line : 36 <18dc6bc> DW_AT_decl_column : 30 <18dc6bd> DW_AT_type : <0x18dc6c3> <18dc6c1> DW_AT_external : 1 <18dc6c1> DW_AT_location : 1 byte block: 5d (DW_OP_reg13 (r13)) <1><18dc6c3>: Abbrev Number: 3 (DW_TAG_pointer_type) <18dc6c4> DW_AT_byte_size : 8 <18dc6c4> DW_AT_type : <0x18dc353> Where DW_AT_type : <0x18dc6c3> further points to : <1><18dc6c3>: Abbrev Number: 3 (DW_TAG_pointer_type) <18dc6c4> DW_AT_byte_size : 8 <18dc6c4> DW_AT_type : <0x18dc353> which belongs to: <1><18dc353>: Abbrev Number: 67 (DW_TAG_structure_type) <18dc354> DW_AT_name : (indirect string, offset: 0x56cd): paca_struct <18dc358> DW_AT_byte_size : 2944 <18dc35a> DW_AT_alignment : 128 <18dc35b> DW_AT_decl_file : 48 <18dc35c> DW_AT_decl_line : 61 <18dc35d> DW_AT_decl_column : 8 <18dc35d> DW_AT_sibling : <0x18dc6b4> <<>> Similar is case with "r1". <<>> <1><18dd772>: Abbrev Number: 129 (DW_TAG_variable) <18dd774> DW_AT_name : (indirect string, offset: 0x11ba): current_stack_pointer <18dd778> DW_AT_decl_file : 51 <18dd779> DW_AT_decl_line : 1468 <18dd77b> DW_AT_decl_column : 24 <18dd77c> DW_AT_type : <0x18da5cd> <18dd780> DW_AT_external : 1 <18dd780> DW_AT_location : 1 byte block: 51 (DW_OP_reg1 (r1)) where 18da5cd is: <1><18da5cd>: Abbrev Number: 47 (DW_TAG_base_type) <18da5ce> DW_AT_byte_size : 8 <18da5cf> DW_AT_encoding : 7 (unsigned) <18da5d0> DW_AT_name : (indirect string, offset: 0x55c7): long unsigned int <<>> To identify data type for these two special cases, iterate over variables in the CU die (Compile Unit) and match it with the register. If the variable is a base type, ie die_get_real_type will return NULL here, set offset to zero. With the changes, data type for "paca_struct" and "long unsigned int" for r1 is identified. Snippet from ./perf report -s type,type_off 12.85% long unsigned int long unsigned int +0 (no field) 4.68% struct paca_struct struct paca_struct +2312 (__current) 4.57% struct paca_struct struct paca_struct +2354 (irq_soft_mask) Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> --- tools/perf/util/annotate-data.c | 40 ++++++++++++++++++++++++++++ tools/perf/util/annotate.c | 8 ++++++ tools/perf/util/annotate.h | 1 + tools/perf/util/include/dwarf-regs.h | 1 + 4 files changed, 50 insertions(+)