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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Convert sample address to data type using DWARF debug info.
*
* Written by Namhyung Kim <namhyung@kernel.org>
*/
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <linux/zalloc.h>
#include "annotate.h"
#include "annotate-data.h"
#include "debuginfo.h"
#include "debug.h"
#include "dso.h"
#include "dwarf-regs.h"
#include "evsel.h"
#include "evlist.h"
#include "map.h"
#include "map_symbol.h"
#include "sort.h"
#include "strbuf.h"
#include "symbol.h"
#include "symbol_conf.h"
#include "thread.h"
/* register number of the stack pointer */
#define X86_REG_SP 7
static void delete_var_types(struct die_var_type *var_types);
#define pr_debug_dtp(fmt, ...) \
do { \
if (debug_type_profile) \
pr_info(fmt, ##__VA_ARGS__); \
else \
pr_debug3(fmt, ##__VA_ARGS__); \
} while (0)
void pr_debug_type_name(Dwarf_Die *die, enum type_state_kind kind)
{
struct strbuf sb;
char *str;
Dwarf_Word size = 0;
if (!debug_type_profile && verbose < 3)
return;
switch (kind) {
case TSR_KIND_INVALID:
pr_info("\n");
return;
case TSR_KIND_PERCPU_BASE:
pr_info(" percpu base\n");
return;
case TSR_KIND_CONST:
pr_info(" constant\n");
return;
case TSR_KIND_POINTER:
pr_info(" pointer");
/* it also prints the type info */
break;
case TSR_KIND_CANARY:
pr_info(" stack canary\n");
return;
case TSR_KIND_TYPE:
default:
break;
}
dwarf_aggregate_size(die, &size);
strbuf_init(&sb, 32);
die_get_typename_from_type(die, &sb);
str = strbuf_detach(&sb, NULL);
pr_info(" type='%s' size=%#lx (die:%#lx)\n",
str, (long)size, (long)dwarf_dieoffset(die));
free(str);
}
static void pr_debug_location(Dwarf_Die *die, u64 pc, int reg)
{
ptrdiff_t off = 0;
Dwarf_Attribute attr;
Dwarf_Addr base, start, end;
Dwarf_Op *ops;
size_t nops;
if (!debug_type_profile && verbose < 3)
return;
if (dwarf_attr(die, DW_AT_location, &attr) == NULL)
return;
while ((off = dwarf_getlocations(&attr, off, &base, &start, &end, &ops, &nops)) > 0) {
if (reg != DWARF_REG_PC && end <= pc)
continue;
if (reg != DWARF_REG_PC && start > pc)
break;
pr_info(" variable location: ");
switch (ops->atom) {
case DW_OP_reg0 ...DW_OP_reg31:
pr_info("reg%d\n", ops->atom - DW_OP_reg0);
break;
case DW_OP_breg0 ...DW_OP_breg31:
pr_info("base=reg%d, offset=%#lx\n",
ops->atom - DW_OP_breg0, (long)ops->number);
break;
case DW_OP_regx:
pr_info("reg%ld\n", (long)ops->number);
break;
case DW_OP_bregx:
pr_info("base=reg%ld, offset=%#lx\n",
(long)ops->number, (long)ops->number2);
break;
case DW_OP_fbreg:
pr_info("use frame base, offset=%#lx\n", (long)ops->number);
break;
case DW_OP_addr:
pr_info("address=%#lx\n", (long)ops->number);
break;
default:
pr_info("unknown: code=%#x, number=%#lx\n",
ops->atom, (long)ops->number);
break;
}
break;
}
}
static void pr_debug_scope(Dwarf_Die *scope_die)
{
int tag;
if (!debug_type_profile && verbose < 3)
return;
pr_info("(die:%lx) ", (long)dwarf_dieoffset(scope_die));
tag = dwarf_tag(scope_die);
if (tag == DW_TAG_subprogram)
pr_info("[function] %s\n", dwarf_diename(scope_die));
else if (tag == DW_TAG_inlined_subroutine)
pr_info("[inlined] %s\n", dwarf_diename(scope_die));
else if (tag == DW_TAG_lexical_block)
pr_info("[block]\n");
else
pr_info("[unknown] tag=%x\n", tag);
}
bool has_reg_type(struct type_state *state, int reg)
{
return (unsigned)reg < ARRAY_SIZE(state->regs);
}
static void init_type_state(struct type_state *state, struct arch *arch)
{
memset(state, 0, sizeof(*state));
INIT_LIST_HEAD(&state->stack_vars);
if (arch__is(arch, "x86")) {
state->regs[0].caller_saved = true;
state->regs[1].caller_saved = true;
state->regs[2].caller_saved = true;
state->regs[4].caller_saved = true;
state->regs[5].caller_saved = true;
state->regs[8].caller_saved = true;
state->regs[9].caller_saved = true;
state->regs[10].caller_saved = true;
state->regs[11].caller_saved = true;
state->ret_reg = 0;
state->stack_reg = X86_REG_SP;
}
}
static void exit_type_state(struct type_state *state)
{
struct type_state_stack *stack, *tmp;
list_for_each_entry_safe(stack, tmp, &state->stack_vars, list) {
list_del(&stack->list);
free(stack);
}
}
/*
* Compare type name and size to maintain them in a tree.
* I'm not sure if DWARF would have information of a single type in many
* different places (compilation units). If not, it could compare the
* offset of the type entry in the .debug_info section.
*/
static int data_type_cmp(const void *_key, const struct rb_node *node)
{
const struct annotated_data_type *key = _key;
struct annotated_data_type *type;
type = rb_entry(node, struct annotated_data_type, node);
if (key->self.size != type->self.size)
return key->self.size - type->self.size;
return strcmp(key->self.type_name, type->self.type_name);
}
static bool data_type_less(struct rb_node *node_a, const struct rb_node *node_b)
{
struct annotated_data_type *a, *b;
a = rb_entry(node_a, struct annotated_data_type, node);
b = rb_entry(node_b, struct annotated_data_type, node);
if (a->self.size != b->self.size)
return a->self.size < b->self.size;
return strcmp(a->self.type_name, b->self.type_name) < 0;
}
/* Recursively add new members for struct/union */
static int __add_member_cb(Dwarf_Die *die, void *arg)
{
struct annotated_member *parent = arg;
struct annotated_member *member;
Dwarf_Die member_type, die_mem;
Dwarf_Word size, loc, bit_size = 0;
Dwarf_Attribute attr;
struct strbuf sb;
int tag;
if (dwarf_tag(die) != DW_TAG_member)
return DIE_FIND_CB_SIBLING;
member = zalloc(sizeof(*member));
if (member == NULL)
return DIE_FIND_CB_END;
strbuf_init(&sb, 32);
die_get_typename(die, &sb);
__die_get_real_type(die, &member_type);
if (dwarf_tag(&member_type) == DW_TAG_typedef)
die_get_real_type(&member_type, &die_mem);
else
die_mem = member_type;
if (dwarf_aggregate_size(&die_mem, &size) < 0)
size = 0;
if (dwarf_attr_integrate(die, DW_AT_data_member_location, &attr))
dwarf_formudata(&attr, &loc);
else {
/* bitfield member */
if (dwarf_attr_integrate(die, DW_AT_data_bit_offset, &attr) &&
dwarf_formudata(&attr, &loc) == 0)
loc /= 8;
else
loc = 0;
if (dwarf_attr_integrate(die, DW_AT_bit_size, &attr) &&
dwarf_formudata(&attr, &bit_size) == 0)
size = (bit_size + 7) / 8;
}
member->type_name = strbuf_detach(&sb, NULL);
/* member->var_name can be NULL */
if (dwarf_diename(die)) {
if (bit_size) {
if (asprintf(&member->var_name, "%s:%ld",
dwarf_diename(die), (long)bit_size) < 0)
member->var_name = NULL;
} else {
member->var_name = strdup(dwarf_diename(die));
}
if (member->var_name == NULL) {
free(member);
return DIE_FIND_CB_END;
}
}
member->size = size;
member->offset = loc + parent->offset;
INIT_LIST_HEAD(&member->children);
list_add_tail(&member->node, &parent->children);
tag = dwarf_tag(&die_mem);
switch (tag) {
case DW_TAG_structure_type:
case DW_TAG_union_type:
die_find_child(&die_mem, __add_member_cb, member, &die_mem);
break;
default:
break;
}
return DIE_FIND_CB_SIBLING;
}
static void add_member_types(struct annotated_data_type *parent, Dwarf_Die *type)
{
Dwarf_Die die_mem;
die_find_child(type, __add_member_cb, &parent->self, &die_mem);
}
static void delete_members(struct annotated_member *member)
{
struct annotated_member *child, *tmp;
list_for_each_entry_safe(child, tmp, &member->children, node) {
list_del(&child->node);
delete_members(child);
zfree(&child->type_name);
zfree(&child->var_name);
free(child);
}
}
static struct annotated_data_type *dso__findnew_data_type(struct dso *dso,
Dwarf_Die *type_die)
{
struct annotated_data_type *result = NULL;
struct annotated_data_type key;
struct rb_node *node;
struct strbuf sb;
char *type_name;
Dwarf_Word size;
strbuf_init(&sb, 32);
if (die_get_typename_from_type(type_die, &sb) < 0)
strbuf_add(&sb, "(unknown type)", 14);
type_name = strbuf_detach(&sb, NULL);
if (dwarf_tag(type_die) == DW_TAG_typedef)
die_get_real_type(type_die, type_die);
dwarf_aggregate_size(type_die, &size);
/* Check existing nodes in dso->data_types tree */
key.self.type_name = type_name;
key.self.size = size;
node = rb_find(&key, dso__data_types(dso), data_type_cmp);
if (node) {
result = rb_entry(node, struct annotated_data_type, node);
free(type_name);
return result;
}
/* If not, add a new one */
result = zalloc(sizeof(*result));
if (result == NULL) {
free(type_name);
return NULL;
}
result->self.type_name = type_name;
result->self.size = size;
INIT_LIST_HEAD(&result->self.children);
if (symbol_conf.annotate_data_member)
add_member_types(result, type_die);
rb_add(&result->node, dso__data_types(dso), data_type_less);
return result;
}
static bool find_cu_die(struct debuginfo *di, u64 pc, Dwarf_Die *cu_die)
{
Dwarf_Off off, next_off;
size_t header_size;
if (dwarf_addrdie(di->dbg, pc, cu_die) != NULL)
return cu_die;
/*
* There are some kernels don't have full aranges and contain only a few
* aranges entries. Fallback to iterate all CU entries in .debug_info
* in case it's missing.
*/
off = 0;
while (dwarf_nextcu(di->dbg, off, &next_off, &header_size,
NULL, NULL, NULL) == 0) {
if (dwarf_offdie(di->dbg, off + header_size, cu_die) &&
dwarf_haspc(cu_die, pc))
return true;
off = next_off;
}
return false;
}
enum type_match_result {
PERF_TMR_UNKNOWN = 0,
PERF_TMR_OK,
PERF_TMR_NO_TYPE,
PERF_TMR_NO_POINTER,
PERF_TMR_NO_SIZE,
PERF_TMR_BAD_OFFSET,
PERF_TMR_BAIL_OUT,
};
static const char *match_result_str(enum type_match_result tmr)
{
switch (tmr) {
case PERF_TMR_OK:
return "Good!";
case PERF_TMR_NO_TYPE:
return "no type information";
case PERF_TMR_NO_POINTER:
return "no/void pointer";
case PERF_TMR_NO_SIZE:
return "type size is unknown";
case PERF_TMR_BAD_OFFSET:
return "offset bigger than size";
case PERF_TMR_UNKNOWN:
case PERF_TMR_BAIL_OUT:
default:
return "invalid state";
}
}
static bool is_pointer_type(Dwarf_Die *type_die)
{
int tag = dwarf_tag(type_die);
return tag == DW_TAG_pointer_type || tag == DW_TAG_array_type;
}
static bool is_compound_type(Dwarf_Die *type_die)
{
int tag = dwarf_tag(type_die);
return tag == DW_TAG_structure_type || tag == DW_TAG_union_type;
}
/* returns if Type B has better information than Type A */
static bool is_better_type(Dwarf_Die *type_a, Dwarf_Die *type_b)
{
Dwarf_Word size_a, size_b;
Dwarf_Die die_a, die_b;
/* pointer type is preferred */
if (is_pointer_type(type_a) != is_pointer_type(type_b))
return is_pointer_type(type_b);
if (is_pointer_type(type_b)) {
/*
* We want to compare the target type, but 'void *' can fail to
* get the target type.
*/
if (die_get_real_type(type_a, &die_a) == NULL)
return true;
if (die_get_real_type(type_b, &die_b) == NULL)
return false;
type_a = &die_a;
type_b = &die_b;
}
/* bigger type is preferred */
if (dwarf_aggregate_size(type_a, &size_a) < 0 ||
dwarf_aggregate_size(type_b, &size_b) < 0)
return false;
if (size_a != size_b)
return size_a < size_b;
/* struct or union is preferred */
if (is_compound_type(type_a) != is_compound_type(type_b))
return is_compound_type(type_b);
/* typedef is preferred */
if (dwarf_tag(type_b) == DW_TAG_typedef)
return true;
return false;
}
/* The type info will be saved in @type_die */
static enum type_match_result check_variable(struct data_loc_info *dloc,
Dwarf_Die *var_die,
Dwarf_Die *type_die, int reg,
int offset, bool is_fbreg)
{
Dwarf_Word size;
bool needs_pointer = true;
Dwarf_Die sized_type;
if (reg == DWARF_REG_PC)
needs_pointer = false;
else if (reg == dloc->fbreg || is_fbreg)
needs_pointer = false;
else if (arch__is(dloc->arch, "x86") && reg == X86_REG_SP)
needs_pointer = false;
/* Get the type of the variable */
if (__die_get_real_type(var_die, type_die) == NULL)
return PERF_TMR_NO_TYPE;
/*
* Usually it expects a pointer type for a memory access.
* Convert to a real type it points to. But global variables
* and local variables are accessed directly without a pointer.
*/
if (needs_pointer) {
if (!is_pointer_type(type_die) ||
__die_get_real_type(type_die, type_die) == NULL)
return PERF_TMR_NO_POINTER;
}
if (dwarf_tag(type_die) == DW_TAG_typedef)
die_get_real_type(type_die, &sized_type);
else
sized_type = *type_die;
/* Get the size of the actual type */
if (dwarf_aggregate_size(&sized_type, &size) < 0)
return PERF_TMR_NO_SIZE;
/* Minimal sanity check */
if ((unsigned)offset >= size)
return PERF_TMR_BAD_OFFSET;
return PERF_TMR_OK;
}
struct type_state_stack *find_stack_state(struct type_state *state,
int offset)
{
struct type_state_stack *stack;
list_for_each_entry(stack, &state->stack_vars, list) {
if (offset == stack->offset)
return stack;
if (stack->compound && stack->offset < offset &&
offset < stack->offset + stack->size)
return stack;
}
return NULL;
}
void set_stack_state(struct type_state_stack *stack, int offset, u8 kind,
Dwarf_Die *type_die)
{
int tag;
Dwarf_Word size;
if (dwarf_aggregate_size(type_die, &size) < 0)
size = 0;
tag = dwarf_tag(type_die);
stack->type = *type_die;
stack->size = size;
stack->offset = offset;
stack->kind = kind;
switch (tag) {
case DW_TAG_structure_type:
case DW_TAG_union_type:
stack->compound = (kind != TSR_KIND_POINTER);
break;
default:
stack->compound = false;
break;
}
}
struct type_state_stack *findnew_stack_state(struct type_state *state,
int offset, u8 kind,
Dwarf_Die *type_die)
{
struct type_state_stack *stack = find_stack_state(state, offset);
if (stack) {
set_stack_state(stack, offset, kind, type_die);
return stack;
}
stack = malloc(sizeof(*stack));
if (stack) {
set_stack_state(stack, offset, kind, type_die);
list_add(&stack->list, &state->stack_vars);
}
return stack;
}
/* Maintain a cache for quick global variable lookup */
struct global_var_entry {
struct rb_node node;
char *name;
u64 start;
u64 end;
u64 die_offset;
};
static int global_var_cmp(const void *_key, const struct rb_node *node)
{
const u64 addr = (uintptr_t)_key;
struct global_var_entry *gvar;
gvar = rb_entry(node, struct global_var_entry, node);
if (gvar->start <= addr && addr < gvar->end)
return 0;
return gvar->start > addr ? -1 : 1;
}
static bool global_var_less(struct rb_node *node_a, const struct rb_node *node_b)
{
struct global_var_entry *gvar_a, *gvar_b;
gvar_a = rb_entry(node_a, struct global_var_entry, node);
gvar_b = rb_entry(node_b, struct global_var_entry, node);
return gvar_a->start < gvar_b->start;
}
static struct global_var_entry *global_var__find(struct data_loc_info *dloc, u64 addr)
{
struct dso *dso = map__dso(dloc->ms->map);
struct rb_node *node;
node = rb_find((void *)(uintptr_t)addr, dso__global_vars(dso), global_var_cmp);
if (node == NULL)
return NULL;
return rb_entry(node, struct global_var_entry, node);
}
static bool global_var__add(struct data_loc_info *dloc, u64 addr,
const char *name, Dwarf_Die *type_die)
{
struct dso *dso = map__dso(dloc->ms->map);
struct global_var_entry *gvar;
Dwarf_Word size;
if (dwarf_aggregate_size(type_die, &size) < 0)
return false;
gvar = malloc(sizeof(*gvar));
if (gvar == NULL)
return false;
gvar->name = name ? strdup(name) : NULL;
if (name && gvar->name == NULL) {
free(gvar);
return false;
}
gvar->start = addr;
gvar->end = addr + size;
gvar->die_offset = dwarf_dieoffset(type_die);
rb_add(&gvar->node, dso__global_vars(dso), global_var_less);
return true;
}
void global_var_type__tree_delete(struct rb_root *root)
{
struct global_var_entry *gvar;
while (!RB_EMPTY_ROOT(root)) {
struct rb_node *node = rb_first(root);
rb_erase(node, root);
gvar = rb_entry(node, struct global_var_entry, node);
zfree(&gvar->name);
free(gvar);
}
}
bool get_global_var_info(struct data_loc_info *dloc, u64 addr,
const char **var_name, int *var_offset)
{
struct addr_location al;
struct symbol *sym;
u64 mem_addr;
/* Kernel symbols might be relocated */
mem_addr = addr + map__reloc(dloc->ms->map);
addr_location__init(&al);
sym = thread__find_symbol_fb(dloc->thread, dloc->cpumode,
mem_addr, &al);
if (sym) {
*var_name = sym->name;
/* Calculate type offset from the start of variable */
*var_offset = mem_addr - map__unmap_ip(al.map, sym->start);
} else {
*var_name = NULL;
}
addr_location__exit(&al);
if (*var_name == NULL)
return false;
return true;
}
static void global_var__collect(struct data_loc_info *dloc)
{
Dwarf *dwarf = dloc->di->dbg;
Dwarf_Off off, next_off;
Dwarf_Die cu_die, type_die;
size_t header_size;
/* Iterate all CU and collect global variables that have no location in a register. */
off = 0;
while (dwarf_nextcu(dwarf, off, &next_off, &header_size,
NULL, NULL, NULL) == 0) {
struct die_var_type *var_types = NULL;
struct die_var_type *pos;
if (dwarf_offdie(dwarf, off + header_size, &cu_die) == NULL) {
off = next_off;
continue;
}
die_collect_global_vars(&cu_die, &var_types);
for (pos = var_types; pos; pos = pos->next) {
const char *var_name = NULL;
int var_offset = 0;
if (pos->reg != -1)
continue;
if (!dwarf_offdie(dwarf, pos->die_off, &type_die))
continue;
if (!get_global_var_info(dloc, pos->addr, &var_name,
&var_offset))
continue;
if (var_offset != 0)
continue;
global_var__add(dloc, pos->addr, var_name, &type_die);
}
delete_var_types(var_types);
off = next_off;
}
}
bool get_global_var_type(Dwarf_Die *cu_die, struct data_loc_info *dloc,
u64 ip, u64 var_addr, int *var_offset,
Dwarf_Die *type_die)
{
u64 pc;
int offset;
const char *var_name = NULL;
struct global_var_entry *gvar;
struct dso *dso = map__dso(dloc->ms->map);
Dwarf_Die var_die;
if (RB_EMPTY_ROOT(dso__global_vars(dso)))
global_var__collect(dloc);
gvar = global_var__find(dloc, var_addr);
if (gvar) {
if (!dwarf_offdie(dloc->di->dbg, gvar->die_offset, type_die))
return false;
*var_offset = var_addr - gvar->start;
return true;
}
/* Try to get the variable by address first */
if (die_find_variable_by_addr(cu_die, var_addr, &var_die, &offset) &&
check_variable(dloc, &var_die, type_die, DWARF_REG_PC, offset,
/*is_fbreg=*/false) == PERF_TMR_OK) {
var_name = dwarf_diename(&var_die);
*var_offset = offset;
goto ok;
}
if (!get_global_var_info(dloc, var_addr, &var_name, var_offset))
return false;
pc = map__rip_2objdump(dloc->ms->map, ip);
/* Try to get the name of global variable */
if (die_find_variable_at(cu_die, var_name, pc, &var_die) &&
check_variable(dloc, &var_die, type_die, DWARF_REG_PC, *var_offset,
/*is_fbreg=*/false) == PERF_TMR_OK)
goto ok;
return false;
ok:
/* The address should point to the start of the variable */
global_var__add(dloc, var_addr - *var_offset, var_name, type_die);
return true;
}
static bool die_is_same(Dwarf_Die *die_a, Dwarf_Die *die_b)
{
return (die_a->cu == die_b->cu) && (die_a->addr == die_b->addr);
}
/**
* update_var_state - Update type state using given variables
* @state: type state table
* @dloc: data location info
* @addr: instruction address to match with variable
* @insn_offset: instruction offset (for debug)
* @var_types: list of variables with type info
*
* This function fills the @state table using @var_types info. Each variable
* is used only at the given location and updates an entry in the table.
*/
static void update_var_state(struct type_state *state, struct data_loc_info *dloc,
u64 addr, u64 insn_offset, struct die_var_type *var_types)
{
Dwarf_Die mem_die;
struct die_var_type *var;
int fbreg = dloc->fbreg;
int fb_offset = 0;
if (dloc->fb_cfa) {
if (die_get_cfa(dloc->di->dbg, addr, &fbreg, &fb_offset) < 0)
fbreg = -1;
}
for (var = var_types; var != NULL; var = var->next) {
if (var->addr != addr)
continue;
/* Get the type DIE using the offset */
if (!dwarf_offdie(dloc->di->dbg, var->die_off, &mem_die))
continue;
if (var->reg == DWARF_REG_FB || var->reg == fbreg) {
int offset = var->offset;
struct type_state_stack *stack;
if (var->reg != DWARF_REG_FB)
offset -= fb_offset;
stack = find_stack_state(state, offset);
if (stack && stack->kind == TSR_KIND_TYPE &&
!is_better_type(&stack->type, &mem_die))
continue;
findnew_stack_state(state, offset, TSR_KIND_TYPE,
&mem_die);
pr_debug_dtp("var [%"PRIx64"] -%#x(stack)",
insn_offset, -offset);
pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
} else if (has_reg_type(state, var->reg) && var->offset == 0) {
struct type_state_reg *reg;
Dwarf_Die orig_type;
reg = &state->regs[var->reg];
if (reg->ok && reg->kind == TSR_KIND_TYPE &&
!is_better_type(®->type, &mem_die))
continue;
orig_type = reg->type;
reg->type = mem_die;
reg->kind = TSR_KIND_TYPE;
reg->ok = true;
pr_debug_dtp("var [%"PRIx64"] reg%d",
insn_offset, var->reg);
pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
/*
* If this register is directly copied from another and it gets a
* better type, also update the type of the source register. This
* is usually the case of container_of() macro with offset of 0.
*/
if (has_reg_type(state, reg->copied_from)) {
struct type_state_reg *copy_reg;
copy_reg = &state->regs[reg->copied_from];
/* TODO: check if type is compatible or embedded */
if (!copy_reg->ok || (copy_reg->kind != TSR_KIND_TYPE) ||
!die_is_same(©_reg->type, &orig_type) ||
!is_better_type(©_reg->type, &mem_die))
continue;
copy_reg->type = mem_die;
pr_debug_dtp("var [%"PRIx64"] copyback reg%d",
insn_offset, reg->copied_from);
pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
}
}
}
}
/**
* 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.
*/
static void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
Dwarf_Die *cu_die, struct disasm_line *dl)
{
if (dloc->arch->update_insn_state)
dloc->arch->update_insn_state(state, dloc, cu_die, dl);
}
/*
* Prepend this_blocks (from the outer scope) to full_blocks, removing
* duplicate disasm line.
*/
static void prepend_basic_blocks(struct list_head *this_blocks,
struct list_head *full_blocks)
{
struct annotated_basic_block *first_bb, *last_bb;
last_bb = list_last_entry(this_blocks, typeof(*last_bb), list);
first_bb = list_first_entry(full_blocks, typeof(*first_bb), list);
if (list_empty(full_blocks))
goto out;
/* Last insn in this_blocks should be same as first insn in full_blocks */
if (last_bb->end != first_bb->begin) {
pr_debug("prepend basic blocks: mismatched disasm line %"PRIx64" -> %"PRIx64"\n",
last_bb->end->al.offset, first_bb->begin->al.offset);
goto out;
}
/* Is the basic block have only one disasm_line? */
if (last_bb->begin == last_bb->end) {
list_del(&last_bb->list);
free(last_bb);
goto out;
}
/* Point to the insn before the last when adding this block to full_blocks */
last_bb->end = list_prev_entry(last_bb->end, al.node);
out:
list_splice(this_blocks, full_blocks);
}
static void delete_basic_blocks(struct list_head *basic_blocks)
{
struct annotated_basic_block *bb, *tmp;
list_for_each_entry_safe(bb, tmp, basic_blocks, list) {
list_del(&bb->list);
free(bb);
}
}
/* Make sure all variables have a valid start address */
static void fixup_var_address(struct die_var_type *var_types, u64 addr)
{
while (var_types) {
/*
* Some variables have no address range meaning it's always
* available in the whole scope. Let's adjust the start
* address to the start of the scope.
*/
if (var_types->addr == 0)
var_types->addr = addr;
var_types = var_types->next;
}
}
static void delete_var_types(struct die_var_type *var_types)
{
while (var_types) {
struct die_var_type *next = var_types->next;
free(var_types);
var_types = next;
}
}
/* should match to is_stack_canary() in util/annotate.c */
static void setup_stack_canary(struct data_loc_info *dloc)
{
if (arch__is(dloc->arch, "x86")) {
dloc->op->segment = INSN_SEG_X86_GS;
dloc->op->imm = true;
dloc->op->offset = 40;
}
}
/*
* It's at the target address, check if it has a matching type.
* It returns PERF_TMR_BAIL_OUT when it looks up per-cpu variables which
* are similar to global variables and no additional info is needed.
*/
static enum type_match_result check_matching_type(struct type_state *state,
struct data_loc_info *dloc,
Dwarf_Die *cu_die,
struct disasm_line *dl,
Dwarf_Die *type_die)
{
Dwarf_Word size;
u32 insn_offset = dl->al.offset;
int reg = dloc->op->reg1;
int offset = dloc->op->offset;
const char *offset_sign = "";
bool retry = true;
if (offset < 0) {
offset = -offset;
offset_sign = "-";
}
again:
pr_debug_dtp("chk [%x] reg%d offset=%s%#x ok=%d kind=%d ",
insn_offset, reg, offset_sign, offset,
state->regs[reg].ok, state->regs[reg].kind);
if (!state->regs[reg].ok)
goto check_non_register;
if (state->regs[reg].kind == TSR_KIND_TYPE) {
Dwarf_Die sized_type;
struct strbuf sb;
strbuf_init(&sb, 32);
die_get_typename_from_type(&state->regs[reg].type, &sb);
pr_debug_dtp("(%s)", sb.buf);
strbuf_release(&sb);
/*
* Normal registers should hold a pointer (or array) to
* dereference a memory location.
*/
if (!is_pointer_type(&state->regs[reg].type)) {
if (dloc->op->offset < 0 && reg != state->stack_reg)
goto check_kernel;
return PERF_TMR_NO_POINTER;
}
/* Remove the pointer and get the target type */
if (__die_get_real_type(&state->regs[reg].type, type_die) == NULL)
return PERF_TMR_NO_POINTER;
dloc->type_offset = dloc->op->offset;
if (dwarf_tag(type_die) == DW_TAG_typedef)
die_get_real_type(type_die, &sized_type);
else
sized_type = *type_die;
/* Get the size of the actual type */
if (dwarf_aggregate_size(&sized_type, &size) < 0 ||
(unsigned)dloc->type_offset >= size)
return PERF_TMR_BAD_OFFSET;
return PERF_TMR_OK;
}
if (state->regs[reg].kind == TSR_KIND_POINTER) {
pr_debug_dtp("percpu ptr");
/*
* It's actaully pointer but the address was calculated using
* some arithmetic. So it points to the actual type already.
*/
*type_die = state->regs[reg].type;
dloc->type_offset = dloc->op->offset;
/* Get the size of the actual type */
if (dwarf_aggregate_size(type_die, &size) < 0 ||
(unsigned)dloc->type_offset >= size)
return PERF_TMR_BAIL_OUT;
return PERF_TMR_OK;
}
if (state->regs[reg].kind == TSR_KIND_CANARY) {
pr_debug_dtp("stack canary");
/*
* This is a saved value of the stack canary which will be handled
* in the outer logic when it returns failure here. Pretend it's
* from the stack canary directly.
*/
setup_stack_canary(dloc);
return PERF_TMR_BAIL_OUT;
}
if (state->regs[reg].kind == TSR_KIND_PERCPU_BASE) {
u64 var_addr = dloc->op->offset;
int var_offset;
pr_debug_dtp("percpu var");
if (dloc->op->multi_regs) {
int reg2 = dloc->op->reg2;
if (dloc->op->reg2 == reg)
reg2 = dloc->op->reg1;
if (has_reg_type(state, reg2) && state->regs[reg2].ok &&
state->regs[reg2].kind == TSR_KIND_CONST)
var_addr += state->regs[reg2].imm_value;
}
if (get_global_var_type(cu_die, dloc, dloc->ip, var_addr,
&var_offset, type_die)) {
dloc->type_offset = var_offset;
return PERF_TMR_OK;
}
/* No need to retry per-cpu (global) variables */
return PERF_TMR_BAIL_OUT;
}
check_non_register:
if (reg == dloc->fbreg) {
struct type_state_stack *stack;
pr_debug_dtp("fbreg");
stack = find_stack_state(state, dloc->type_offset);
if (stack == NULL) {
if (retry) {
pr_debug_dtp(" : retry\n");
retry = false;
/* update type info it's the first store to the stack */
update_insn_state(state, dloc, cu_die, dl);
goto again;
}
return PERF_TMR_NO_TYPE;
}
if (stack->kind == TSR_KIND_CANARY) {
setup_stack_canary(dloc);
return PERF_TMR_BAIL_OUT;
}
if (stack->kind != TSR_KIND_TYPE)
return PERF_TMR_NO_TYPE;
*type_die = stack->type;
/* Update the type offset from the start of slot */
dloc->type_offset -= stack->offset;
return PERF_TMR_OK;
}
if (dloc->fb_cfa) {
struct type_state_stack *stack;
u64 pc = map__rip_2objdump(dloc->ms->map, dloc->ip);
int fbreg, fboff;
pr_debug_dtp("cfa");
if (die_get_cfa(dloc->di->dbg, pc, &fbreg, &fboff) < 0)
fbreg = -1;
if (reg != fbreg)
return PERF_TMR_NO_TYPE;
stack = find_stack_state(state, dloc->type_offset - fboff);
if (stack == NULL) {
if (retry) {
pr_debug_dtp(" : retry\n");
retry = false;
/* update type info it's the first store to the stack */
update_insn_state(state, dloc, cu_die, dl);
goto again;
}
return PERF_TMR_NO_TYPE;
}
if (stack->kind == TSR_KIND_CANARY) {
setup_stack_canary(dloc);
return PERF_TMR_BAIL_OUT;
}
if (stack->kind != TSR_KIND_TYPE)
return PERF_TMR_NO_TYPE;
*type_die = stack->type;
/* Update the type offset from the start of slot */
dloc->type_offset -= fboff + stack->offset;
return PERF_TMR_OK;
}
check_kernel:
if (dso__kernel(map__dso(dloc->ms->map))) {
u64 addr;
/* Direct this-cpu access like "%gs:0x34740" */
if (dloc->op->segment == INSN_SEG_X86_GS && dloc->op->imm &&
arch__is(dloc->arch, "x86")) {
pr_debug_dtp("this-cpu var");
addr = dloc->op->offset;
if (get_global_var_type(cu_die, dloc, dloc->ip, addr,
&offset, type_die)) {
dloc->type_offset = offset;
return PERF_TMR_OK;
}
return PERF_TMR_BAIL_OUT;
}
/* Access to global variable like "-0x7dcf0500(,%rdx,8)" */
if (dloc->op->offset < 0 && reg != state->stack_reg) {
addr = (s64) dloc->op->offset;
if (get_global_var_type(cu_die, dloc, dloc->ip, addr,
&offset, type_die)) {
pr_debug_dtp("global var");
dloc->type_offset = offset;
return PERF_TMR_OK;
}
return PERF_TMR_BAIL_OUT;
}
}
return PERF_TMR_UNKNOWN;
}
/* Iterate instructions in basic blocks and update type table */
static enum type_match_result find_data_type_insn(struct data_loc_info *dloc,
struct list_head *basic_blocks,
struct die_var_type *var_types,
Dwarf_Die *cu_die,
Dwarf_Die *type_die)
{
struct type_state state;
struct symbol *sym = dloc->ms->sym;
struct annotation *notes = symbol__annotation(sym);
struct annotated_basic_block *bb;
enum type_match_result ret = PERF_TMR_UNKNOWN;
init_type_state(&state, dloc->arch);
list_for_each_entry(bb, basic_blocks, list) {
struct disasm_line *dl = bb->begin;
BUG_ON(bb->begin->al.offset == -1 || bb->end->al.offset == -1);
pr_debug_dtp("bb: [%"PRIx64" - %"PRIx64"]\n",
bb->begin->al.offset, bb->end->al.offset);
list_for_each_entry_from(dl, ¬es->src->source, al.node) {
u64 this_ip = sym->start + dl->al.offset;
u64 addr = map__rip_2objdump(dloc->ms->map, this_ip);
/* Skip comment or debug info lines */
if (dl->al.offset == -1)
continue;
/* Update variable type at this address */
update_var_state(&state, dloc, addr, dl->al.offset, var_types);
if (this_ip == dloc->ip) {
ret = check_matching_type(&state, dloc,
cu_die, dl, type_die);
pr_debug_dtp(" : %s\n", match_result_str(ret));
goto out;
}
/* Update type table after processing the instruction */
update_insn_state(&state, dloc, cu_die, dl);
if (dl == bb->end)
break;
}
}
out:
exit_type_state(&state);
return ret;
}
static int arch_supports_insn_tracking(struct data_loc_info *dloc)
{
if ((arch__is(dloc->arch, "x86")) || (arch__is(dloc->arch, "powerpc")))
return 1;
return 0;
}
/*
* Construct a list of basic blocks for each scope with variables and try to find
* the data type by updating a type state table through instructions.
*/
static enum type_match_result find_data_type_block(struct data_loc_info *dloc,
Dwarf_Die *cu_die,
Dwarf_Die *scopes,
int nr_scopes,
Dwarf_Die *type_die)
{
LIST_HEAD(basic_blocks);
struct die_var_type *var_types = NULL;
u64 src_ip, dst_ip, prev_dst_ip;
enum type_match_result ret = PERF_TMR_UNKNOWN;
/* TODO: other architecture support */
if (!arch_supports_insn_tracking(dloc))
return PERF_TMR_BAIL_OUT;
prev_dst_ip = dst_ip = dloc->ip;
for (int i = nr_scopes - 1; i >= 0; i--) {
Dwarf_Addr base, start, end;
LIST_HEAD(this_blocks);
if (dwarf_ranges(&scopes[i], 0, &base, &start, &end) < 0)
break;
pr_debug_dtp("scope: [%d/%d] ", i + 1, nr_scopes);
pr_debug_scope(&scopes[i]);
src_ip = map__objdump_2rip(dloc->ms->map, start);
again:
/* Get basic blocks for this scope */
if (annotate_get_basic_blocks(dloc->ms->sym, src_ip, dst_ip,
&this_blocks) < 0) {
/* Try previous block if they are not connected */
if (prev_dst_ip != dst_ip) {
dst_ip = prev_dst_ip;
goto again;
}
pr_debug_dtp("cannot find a basic block from %"PRIx64" to %"PRIx64"\n",
src_ip - dloc->ms->sym->start,
dst_ip - dloc->ms->sym->start);
continue;
}
prepend_basic_blocks(&this_blocks, &basic_blocks);
/* Get variable info for this scope and add to var_types list */
die_collect_vars(&scopes[i], &var_types);
fixup_var_address(var_types, start);
/* Find from start of this scope to the target instruction */
ret = find_data_type_insn(dloc, &basic_blocks, var_types,
cu_die, type_die);
if (ret == PERF_TMR_OK) {
char buf[64];
int offset = dloc->op->offset;
const char *offset_sign = "";
if (offset < 0) {
offset = -offset;
offset_sign = "-";
}
if (dloc->op->multi_regs)
snprintf(buf, sizeof(buf), "reg%d, reg%d",
dloc->op->reg1, dloc->op->reg2);
else
snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
pr_debug_dtp("found by insn track: %s%#x(%s) type-offset=%#x\n",
offset_sign, offset, buf, dloc->type_offset);
break;
}
if (ret == PERF_TMR_BAIL_OUT)
break;
/* Go up to the next scope and find blocks to the start */
prev_dst_ip = dst_ip;
dst_ip = src_ip;
}
delete_basic_blocks(&basic_blocks);
delete_var_types(var_types);
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)
{
struct annotated_op_loc *loc = dloc->op;
Dwarf_Die cu_die, var_die;
Dwarf_Die *scopes = NULL;
int reg, offset = loc->offset;
int ret = -1;
int i, nr_scopes;
int fbreg = -1;
int fb_offset = 0;
bool is_fbreg = false;
bool found = false;
u64 pc;
char buf[64];
enum type_match_result result = PERF_TMR_UNKNOWN;
const char *offset_sign = "";
if (dloc->op->multi_regs)
snprintf(buf, sizeof(buf), "reg%d, reg%d", dloc->op->reg1, dloc->op->reg2);
else if (dloc->op->reg1 == DWARF_REG_PC)
snprintf(buf, sizeof(buf), "PC");
else
snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
if (offset < 0) {
offset = -offset;
offset_sign = "-";
}
pr_debug_dtp("-----------------------------------------------------------\n");
pr_debug_dtp("find data type for %s%#x(%s) at %s+%#"PRIx64"\n",
offset_sign, offset, buf,
dloc->ms->sym->name, dloc->ip - dloc->ms->sym->start);
/*
* IP is a relative instruction address from the start of the map, as
* it can be randomized/relocated, it needs to translate to PC which is
* a file address for DWARF processing.
*/
pc = map__rip_2objdump(dloc->ms->map, dloc->ip);
/* Get a compile_unit for this address */
if (!find_cu_die(dloc->di, pc, &cu_die)) {
pr_debug_dtp("cannot find CU for address %"PRIx64"\n", pc);
ann_data_stat.no_cuinfo++;
return -1;
}
reg = loc->reg1;
offset = loc->offset;
pr_debug_dtp("CU for %s (die:%#lx)\n",
dwarf_diename(&cu_die), (long)dwarf_dieoffset(&cu_die));
if (reg == DWARF_REG_PC) {
if (get_global_var_type(&cu_die, dloc, dloc->ip, dloc->var_addr,
&offset, type_die)) {
dloc->type_offset = offset;
pr_debug_dtp("found by addr=%#"PRIx64" type_offset=%#x\n",
dloc->var_addr, offset);
pr_debug_type_name(type_die, TSR_KIND_TYPE);
found = true;
goto out;
}
}
/* Get a list of nested scopes - i.e. (inlined) functions and blocks. */
nr_scopes = die_get_scopes(&cu_die, pc, &scopes);
if (reg != DWARF_REG_PC && dwarf_hasattr(&scopes[0], DW_AT_frame_base)) {
Dwarf_Attribute attr;
Dwarf_Block block;
/* Check if the 'reg' is assigned as frame base register */
if (dwarf_attr(&scopes[0], DW_AT_frame_base, &attr) != NULL &&
dwarf_formblock(&attr, &block) == 0 && block.length == 1) {
switch (*block.data) {
case DW_OP_reg0 ... DW_OP_reg31:
fbreg = dloc->fbreg = *block.data - DW_OP_reg0;
break;
case DW_OP_call_frame_cfa:
dloc->fb_cfa = true;
if (die_get_cfa(dloc->di->dbg, pc, &fbreg,
&fb_offset) < 0)
fbreg = -1;
break;
default:
break;
}
pr_debug_dtp("frame base: cfa=%d fbreg=%d\n",
dloc->fb_cfa, fbreg);
}
}
retry:
is_fbreg = (reg == fbreg);
if (is_fbreg)
offset = loc->offset - fb_offset;
/* Search from the inner-most scope to the outer */
for (i = nr_scopes - 1; i >= 0; i--) {
Dwarf_Die mem_die;
int type_offset = offset;
if (reg == DWARF_REG_PC) {
if (!die_find_variable_by_addr(&scopes[i], dloc->var_addr,
&var_die, &type_offset))
continue;
} else {
/* Look up variables/parameters in this scope */
if (!die_find_variable_by_reg(&scopes[i], pc, reg,
&type_offset, is_fbreg, &var_die))
continue;
}
pr_debug_dtp("found \"%s\" (die: %#lx) in scope=%d/%d (die: %#lx) ",
dwarf_diename(&var_die), (long)dwarf_dieoffset(&var_die),
i+1, nr_scopes, (long)dwarf_dieoffset(&scopes[i]));
/* Found a variable, see if it's correct */
result = check_variable(dloc, &var_die, &mem_die, reg, type_offset, is_fbreg);
if (result == PERF_TMR_OK) {
if (reg == DWARF_REG_PC) {
pr_debug_dtp("addr=%#"PRIx64" type_offset=%#x\n",
dloc->var_addr, type_offset);
} else if (reg == DWARF_REG_FB || is_fbreg) {
pr_debug_dtp("stack_offset=%#x type_offset=%#x\n",
fb_offset, type_offset);
} else {
pr_debug_dtp("type_offset=%#x\n", type_offset);
}
if (!found || is_better_type(type_die, &mem_die)) {
*type_die = mem_die;
dloc->type_offset = type_offset;
found = true;
}
} else {
pr_debug_dtp("failed: %s\n", match_result_str(result));
}
pr_debug_location(&var_die, pc, reg);
pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
}
if (!found && loc->multi_regs && reg == loc->reg1 && loc->reg1 != loc->reg2) {
reg = loc->reg2;
goto retry;
}
if (!found && reg != DWARF_REG_PC) {
result = find_data_type_block(dloc, &cu_die, scopes,
nr_scopes, type_die);
if (result == PERF_TMR_OK) {
ann_data_stat.insn_track++;
found = true;
}
}
out:
pr_debug_dtp("final result: ");
if (found) {
pr_debug_type_name(type_die, TSR_KIND_TYPE);
ret = 0;
} else {
switch (result) {
case PERF_TMR_NO_TYPE:
case PERF_TMR_NO_POINTER:
pr_debug_dtp("%s\n", match_result_str(result));
ann_data_stat.no_typeinfo++;
break;
case PERF_TMR_NO_SIZE:
pr_debug_dtp("%s\n", match_result_str(result));
ann_data_stat.invalid_size++;
break;
case PERF_TMR_BAD_OFFSET:
pr_debug_dtp("%s\n", match_result_str(result));
ann_data_stat.bad_offset++;
break;
case PERF_TMR_UNKNOWN:
case PERF_TMR_BAIL_OUT:
case PERF_TMR_OK: /* should not reach here */
default:
pr_debug_dtp("no variable found\n");
ann_data_stat.no_var++;
break;
}
ret = -1;
}
free(scopes);
return ret;
}
/**
* find_data_type - Return a data type at the location
* @dloc: data location
*
* This functions searches the debug information of the binary to get the data
* type it accesses. The exact location is expressed by (ip, reg, offset)
* for pointer variables or (ip, addr) for global variables. Note that global
* variables might update the @dloc->type_offset after finding the start of the
* variable. If it cannot find a global variable by address, it tried to find
* a declaration of the variable using var_name. In that case, @dloc->offset
* won't be updated.
*
* It return %NULL if not found.
*/
struct annotated_data_type *find_data_type(struct data_loc_info *dloc)
{
struct dso *dso = map__dso(dloc->ms->map);
Dwarf_Die type_die;
/*
* The type offset is the same as instruction offset by default.
* But when finding a global variable, the offset won't be valid.
*/
dloc->type_offset = dloc->op->offset;
dloc->fbreg = -1;
if (find_data_type_die(dloc, &type_die) < 0)
return NULL;
return dso__findnew_data_type(dso, &type_die);
}
static int alloc_data_type_histograms(struct annotated_data_type *adt, int nr_entries)
{
int i;
size_t sz = sizeof(struct type_hist);
sz += sizeof(struct type_hist_entry) * adt->self.size;
/* Allocate a table of pointers for each event */
adt->histograms = calloc(nr_entries, sizeof(*adt->histograms));
if (adt->histograms == NULL)
return -ENOMEM;
/*
* Each histogram is allocated for the whole size of the type.
* TODO: Probably we can move the histogram to members.
*/
for (i = 0; i < nr_entries; i++) {
adt->histograms[i] = zalloc(sz);
if (adt->histograms[i] == NULL)
goto err;
}
adt->nr_histograms = nr_entries;
return 0;
err:
while (--i >= 0)
zfree(&(adt->histograms[i]));
zfree(&adt->histograms);
return -ENOMEM;
}
static void delete_data_type_histograms(struct annotated_data_type *adt)
{
for (int i = 0; i < adt->nr_histograms; i++)
zfree(&(adt->histograms[i]));
zfree(&adt->histograms);
adt->nr_histograms = 0;
}
void annotated_data_type__tree_delete(struct rb_root *root)
{
struct annotated_data_type *pos;
while (!RB_EMPTY_ROOT(root)) {
struct rb_node *node = rb_first(root);
rb_erase(node, root);
pos = rb_entry(node, struct annotated_data_type, node);
delete_members(&pos->self);
delete_data_type_histograms(pos);
zfree(&pos->self.type_name);
free(pos);
}
}
/**
* annotated_data_type__update_samples - Update histogram
* @adt: Data type to update
* @evsel: Event to update
* @offset: Offset in the type
* @nr_samples: Number of samples at this offset
* @period: Event count at this offset
*
* This function updates type histogram at @ofs for @evsel. Samples are
* aggregated before calling this function so it can be called with more
* than one samples at a certain offset.
*/
int annotated_data_type__update_samples(struct annotated_data_type *adt,
struct evsel *evsel, int offset,
int nr_samples, u64 period)
{
struct type_hist *h;
if (adt == NULL)
return 0;
if (adt->histograms == NULL) {
int nr = evsel->evlist->core.nr_entries;
if (alloc_data_type_histograms(adt, nr) < 0)
return -1;
}
if (offset < 0 || offset >= adt->self.size)
return -1;
h = adt->histograms[evsel->core.idx];
h->nr_samples += nr_samples;
h->addr[offset].nr_samples += nr_samples;
h->period += period;
h->addr[offset].period += period;
return 0;
}
static void print_annotated_data_header(struct hist_entry *he, struct evsel *evsel)
{
struct dso *dso = map__dso(he->ms.map);
int nr_members = 1;
int nr_samples = he->stat.nr_events;
int width = 7;
const char *val_hdr = "Percent";
if (evsel__is_group_event(evsel)) {
struct hist_entry *pair;
list_for_each_entry(pair, &he->pairs.head, pairs.node)
nr_samples += pair->stat.nr_events;
}
printf("Annotate type: '%s' in %s (%d samples):\n",
he->mem_type->self.type_name, dso__name(dso), nr_samples);
if (evsel__is_group_event(evsel)) {
struct evsel *pos;
int i = 0;
nr_members = 0;
for_each_group_evsel(pos, evsel) {
if (symbol_conf.skip_empty &&
evsel__hists(pos)->stats.nr_samples == 0)
continue;
printf(" event[%d] = %s\n", i++, pos->name);
nr_members++;
}
}
if (symbol_conf.show_total_period) {
width = 11;
val_hdr = "Period";
} else if (symbol_conf.show_nr_samples) {
width = 7;
val_hdr = "Samples";
}
printf("============================================================================\n");
printf("%*s %10s %10s %s\n", (width + 1) * nr_members, val_hdr,
"offset", "size", "field");
}
static void print_annotated_data_value(struct type_hist *h, u64 period, int nr_samples)
{
double percent = h->period ? (100.0 * period / h->period) : 0;
const char *color = get_percent_color(percent);
if (symbol_conf.show_total_period)
color_fprintf(stdout, color, " %11" PRIu64, period);
else if (symbol_conf.show_nr_samples)
color_fprintf(stdout, color, " %7d", nr_samples);
else
color_fprintf(stdout, color, " %7.2f", percent);
}
static void print_annotated_data_type(struct annotated_data_type *mem_type,
struct annotated_member *member,
struct evsel *evsel, int indent)
{
struct annotated_member *child;
struct type_hist *h = mem_type->histograms[evsel->core.idx];
int i, nr_events = 0, samples = 0;
u64 period = 0;
int width = symbol_conf.show_total_period ? 11 : 7;
struct evsel *pos;
for_each_group_evsel(pos, evsel) {
h = mem_type->histograms[pos->core.idx];
if (symbol_conf.skip_empty &&
evsel__hists(pos)->stats.nr_samples == 0)
continue;
samples = 0;
period = 0;
for (i = 0; i < member->size; i++) {
samples += h->addr[member->offset + i].nr_samples;
period += h->addr[member->offset + i].period;
}
print_annotated_data_value(h, period, samples);
nr_events++;
}
printf(" %#10x %#10x %*s%s\t%s",
member->offset, member->size, indent, "", member->type_name,
member->var_name ?: "");
if (!list_empty(&member->children))
printf(" {\n");
list_for_each_entry(child, &member->children, node)
print_annotated_data_type(mem_type, child, evsel, indent + 4);
if (!list_empty(&member->children))
printf("%*s}", (width + 1) * nr_events + 24 + indent, "");
printf(";\n");
}
int hist_entry__annotate_data_tty(struct hist_entry *he, struct evsel *evsel)
{
print_annotated_data_header(he, evsel);
print_annotated_data_type(he->mem_type, &he->mem_type->self, evsel, 0);
printf("\n");
/* move to the next entry */
return '>';
}
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