// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2009-2011, Frederic Weisbecker <[email protected]>
*
* Handle the callchains from the stream in an ad-hoc radix tree and then
* sort them in an rbtree.
*
* Using a radix for code path provides a fast retrieval and factorizes
* memory use. Also that lets us use the paths in a hierarchical graph view.
*
*/
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <errno.h>
#include <math.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include "asm/bug.h"
#include "debug.h"
#include "dso.h"
#include "event.h"
#include "hist.h"
#include "sort.h"
#include "machine.h"
#include "map.h"
#include "callchain.h"
#include "branch.h"
#include "symbol.h"
#include "util.h"
#include "../perf.h"
#define CALLCHAIN_PARAM_DEFAULT \
.mode = CHAIN_GRAPH_ABS, \
.min_percent = 0.5, \
.order = ORDER_CALLEE, \
.key = CCKEY_FUNCTION, \
.value = CCVAL_PERCENT, \
struct callchain_param callchain_param = {
CALLCHAIN_PARAM_DEFAULT
};
/*
* Are there any events usind DWARF callchains?
*
* I.e.
*
* -e cycles/call-graph=dwarf/
*/
bool dwarf_callchain_users;
struct callchain_param callchain_param_default = {
CALLCHAIN_PARAM_DEFAULT
};
/* Used for thread-local struct callchain_cursor. */
static pthread_key_t callchain_cursor;
int parse_callchain_record_opt(const char *arg, struct callchain_param *param)
{
return parse_callchain_record(arg, param);
}
static int parse_callchain_mode(const char *value)
{
if (!strncmp(value, "graph", strlen(value))) {
callchain_param.mode = CHAIN_GRAPH_ABS;
return 0;
}
if (!strncmp(value, "flat", strlen(value))) {
callchain_param.mode = CHAIN_FLAT;
return 0;
}
if (!strncmp(value, "fractal", strlen(value))) {
callchain_param.mode = CHAIN_GRAPH_REL;
return 0;
}
if (!strncmp(value, "folded", strlen(value))) {
callchain_param.mode = CHAIN_FOLDED;
return 0;
}
return -1;
}
static int parse_callchain_order(const char *value)
{
if (!strncmp(value, "caller", strlen(value))) {
callchain_param.order = ORDER_CALLER;
callchain_param.order_set = true;
return 0;
}
if (!strncmp(value, "callee", strlen(value))) {
callchain_param.order = ORDER_CALLEE;
callchain_param.order_set = true;
return 0;
}
return -1;
}
static int parse_callchain_sort_key(const char *value)
{
if (!strncmp(value, "function", strlen(value))) {
callchain_param.key = CCKEY_FUNCTION;
return 0;
}
if (!strncmp(value, "address", strlen(value))) {
callchain_param.key = CCKEY_ADDRESS;
return 0;
}
if (!strncmp(value, "srcline", strlen(value))) {
callchain_param.key = CCKEY_SRCLINE;
return 0;
}
if (!strncmp(value, "branch", strlen(value))) {
callchain_param.branch_callstack = 1;
return 0;
}
return -1;
}
static int parse_callchain_value(const char *value)
{
if (!strncmp(value, "percent", strlen(value))) {
callchain_param.value = CCVAL_PERCENT;
return 0;
}
if (!strncmp(value, "period", strlen(value))) {
callchain_param.value = CCVAL_PERIOD;
return 0;
}
if (!strncmp(value, "count", strlen(value))) {
callchain_param.value = CCVAL_COUNT;
return 0;
}
return -1;
}
static int get_stack_size(const char *str, unsigned long *_size)
{
char *endptr;
unsigned long size;
unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
size = strtoul(str, &endptr, 0);
do {
if (*endptr)
break;
size = round_up(size, sizeof(u64));
if (!size || size > max_size)
break;
*_size = size;
return 0;
} while (0);
pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
max_size, str);
return -1;
}
static int
__parse_callchain_report_opt(const char *arg, bool allow_record_opt)
{
char *tok;
char *endptr, *saveptr = NULL;
bool minpcnt_set = false;
bool record_opt_set = false;
bool try_stack_size = false;
callchain_param.enabled = true;
symbol_conf.use_callchain = true;
if (!arg)
return 0;
while ((tok = strtok_r((char *)arg, ",", &saveptr)) != NULL) {
if (!strncmp(tok, "none", strlen(tok))) {
callchain_param.mode = CHAIN_NONE;
callchain_param.enabled = false;
symbol_conf.use_callchain = false;
return 0;
}
if (!parse_callchain_mode(tok) ||
!parse_callchain_order(tok) ||
!parse_callchain_sort_key(tok) ||
!parse_callchain_value(tok)) {
/* parsing ok - move on to the next */
try_stack_size = false;
goto next;
} else if (allow_record_opt && !record_opt_set) {
if (parse_callchain_record(tok, &callchain_param))
goto try_numbers;
/* assume that number followed by 'dwarf' is stack size */
if (callchain_param.record_mode == CALLCHAIN_DWARF)
try_stack_size = true;
record_opt_set = true;
goto next;
}
try_numbers:
if (try_stack_size) {
unsigned long size = 0;
if (get_stack_size(tok, &size) < 0)
return -1;
callchain_param.dump_size = size;
try_stack_size = false;
} else if (!minpcnt_set) {
/* try to get the min percent */
callchain_param.min_percent = strtod(tok, &endptr);
if (tok == endptr)
return -1;
minpcnt_set = true;
} else {
/* try print limit at last */
callchain_param.print_limit = strtoul(tok, &endptr, 0);
if (tok == endptr)
return -1;
}
next:
arg = NULL;
}
if (callchain_register_param(&callchain_param) < 0) {
pr_err("Can't register callchain params\n");
return -1;
}
return 0;
}
int parse_callchain_report_opt(const char *arg)
{
return __parse_callchain_report_opt(arg, false);
}
int parse_callchain_top_opt(const char *arg)
{
return __parse_callchain_report_opt(arg, true);
}
int parse_callchain_record(const char *arg, struct callchain_param *param)
{
char *tok, *name, *saveptr = NULL;
char *buf;
int ret = -1;
/* We need buffer that we know we can write to. */
buf = malloc(strlen(arg) + 1);
if (!buf)
return -ENOMEM;
strcpy(buf, arg);
tok = strtok_r((char *)buf, ",", &saveptr);
name = tok ? : (char *)buf;
do {
/* Framepointer style */
if (!strncmp(name, "fp", sizeof("fp"))) {
ret = 0;
param->record_mode = CALLCHAIN_FP;
tok = strtok_r(NULL, ",", &saveptr);
if (tok) {
unsigned long size;
size = strtoul(tok, &name, 0);
if (size < (unsigned) sysctl__max_stack())
param->max_stack = size;
}
break;
/* Dwarf style */
} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
const unsigned long default_stack_dump_size = 8192;
ret = 0;
param->record_mode = CALLCHAIN_DWARF;
param->dump_size = default_stack_dump_size;
dwarf_callchain_users = true;
tok = strtok_r(NULL, ",", &saveptr);
if (tok) {
unsigned long size = 0;
ret = get_stack_size(tok, &size);
param->dump_size = size;
}
} else if (!strncmp(name, "lbr", sizeof("lbr"))) {
if (!strtok_r(NULL, ",", &saveptr)) {
param->record_mode = CALLCHAIN_LBR;
ret = 0;
} else
pr_err("callchain: No more arguments "
"needed for --call-graph lbr\n");
break;
} else {
pr_err("callchain: Unknown --call-graph option "
"value: %s\n", arg);
break;
}
} while (0);
free(buf);
return ret;
}
int perf_callchain_config(const char *var, const char *value)
{
char *endptr;
if (!strstarts(var, "call-graph."))
return 0;
var += sizeof("call-graph.") - 1;
if (!strcmp(var, "record-mode"))
return parse_callchain_record_opt(value, &callchain_param);
if (!strcmp(var, "dump-size")) {
unsigned long size = 0;
int ret;
ret = get_stack_size(value, &size);
callchain_param.dump_size = size;
return ret;
}
if (!strcmp(var, "print-type")){
int ret;
ret = parse_callchain_mode(value);
if (ret == -1)
pr_err("Invalid callchain mode: %s\n", value);
return ret;
}
if (!strcmp(var, "order")){
int ret;
ret = parse_callchain_order(value);
if (ret == -1)
pr_err("Invalid callchain order: %s\n", value);
return ret;
}
if (!strcmp(var, "sort-key")){
int ret;
ret = parse_callchain_sort_key(value);
if (ret == -1)
pr_err("Invalid callchain sort key: %s\n", value);
return ret;
}
if (!strcmp(var, "threshold")) {
callchain_param.min_percent = strtod(value, &endptr);
if (value == endptr) {
pr_err("Invalid callchain threshold: %s\n", value);
return -1;
}
}
if (!strcmp(var, "print-limit")) {
callchain_param.print_limit = strtod(value, &endptr);
if (value == endptr) {
pr_err("Invalid callchain print limit: %s\n", value);
return -1;
}
}
return 0;
}
static void
rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
enum chain_mode mode)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
struct callchain_node *rnode;
u64 chain_cumul = callchain_cumul_hits(chain);
while (*p) {
u64 rnode_cumul;
parent = *p;
rnode = rb_entry(parent, struct callchain_node, rb_node);
rnode_cumul = callchain_cumul_hits(rnode);
switch (mode) {
case CHAIN_FLAT:
case CHAIN_FOLDED:
if (rnode->hit < chain->hit)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
break;
case CHAIN_GRAPH_ABS: /* Falldown */
case CHAIN_GRAPH_REL:
if (rnode_cumul < chain_cumul)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
break;
case CHAIN_NONE:
default:
break;
}
}
rb_link_node(&chain->rb_node, parent, p);
rb_insert_color(&chain->rb_node, root);
}
static void
__sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
u64 min_hit)
{
struct rb_node *n;
struct callchain_node *child;
n = rb_first(&node->rb_root_in);
while (n) {
child = rb_entry(n, struct callchain_node, rb_node_in);
n = rb_next(n);
__sort_chain_flat(rb_root, child, min_hit);
}
if (node->hit && node->hit >= min_hit)
rb_insert_callchain(rb_root, node, CHAIN_FLAT);
}
/*
* Once we get every callchains from the stream, we can now
* sort them by hit
*/
static void
sort_chain_flat(struct rb_root *rb_root, struct callchain_root *root,
u64 min_hit, struct callchain_param *param __maybe_unused)
{
*rb_root = RB_ROOT;
__sort_chain_flat(rb_root, &root->node, min_hit);
}
static void __sort_chain_graph_abs(struct callchain_node *node,
u64 min_hit)
{
struct rb_node *n;
struct callchain_node *child;
node->rb_root = RB_ROOT;
n = rb_first(&node->rb_root_in);
while (n) {
child = rb_entry(n, struct callchain_node, rb_node_in);
n = rb_next(n);
__sort_chain_graph_abs(child, min_hit);
if (callchain_cumul_hits(child) >= min_hit)
rb_insert_callchain(&node->rb_root, child,
CHAIN_GRAPH_ABS);
}
}
static void
sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_root *chain_root,
u64 min_hit, struct callchain_param *param __maybe_unused)
{
__sort_chain_graph_abs(&chain_root->node, min_hit);
rb_root->rb_node = chain_root->node.rb_root.rb_node;
}
static void __sort_chain_graph_rel(struct callchain_node *node,
double min_percent)
{
struct rb_node *n;
struct callchain_node *child;
u64 min_hit;
node->rb_root = RB_ROOT;
min_hit = ceil(node->children_hit * min_percent);
n = rb_first(&node->rb_root_in);
while (n) {
child = rb_entry(n, struct callchain_node, rb_node_in);
n = rb_next(n);
__sort_chain_graph_rel(child, min_percent);
if (callchain_cumul_hits(child) >= min_hit)
rb_insert_callchain(&node->rb_root, child,
CHAIN_GRAPH_REL);
}
}
static void
sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_root *chain_root,
u64 min_hit __maybe_unused, struct callchain_param *param)
{
__sort_chain_graph_rel(&chain_root->node, param->min_percent / 100.0);
rb_root->rb_node = chain_root->node.rb_root.rb_node;
}
int callchain_register_param(struct callchain_param *param)
{
switch (param->mode) {
case CHAIN_GRAPH_ABS:
param->sort = sort_chain_graph_abs;
break;
case CHAIN_GRAPH_REL:
param->sort = sort_chain_graph_rel;
break;
case CHAIN_FLAT:
case CHAIN_FOLDED:
param->sort = sort_chain_flat;
break;
case CHAIN_NONE:
default:
return -1;
}
return 0;
}
/*
* Create a child for a parent. If inherit_children, then the new child
* will become the new parent of it's parent children
*/
static struct callchain_node *
create_child(struct callchain_node *parent, bool inherit_children)
{
struct callchain_node *new;
new = zalloc(sizeof(*new));
if (!new) {
perror("not enough memory to create child for code path tree");
return NULL;
}
new->parent = parent;
INIT_LIST_HEAD(&new->val);
INIT_LIST_HEAD(&new->parent_val);
if (inherit_children) {
struct rb_node *n;
struct callchain_node *child;
new->rb_root_in = parent->rb_root_in;
parent->rb_root_in = RB_ROOT;
n = rb_first(&new->rb_root_in);
while (n) {
child = rb_entry(n, struct callchain_node, rb_node_in);
child->parent = new;
n = rb_next(n);
}
/* make it the first child */
rb_link_node(&new->rb_node_in, NULL, &parent->rb_root_in.rb_node);
rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
}
return new;
}
/*
* Fill the node with callchain values
*/
static int
fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
{
struct callchain_cursor_node *cursor_node;
node->val_nr = cursor->nr - cursor->pos;
if (!node->val_nr)
pr_warning("Warning: empty node in callchain tree\n");
cursor_node = callchain_cursor_current(cursor);
while (cursor_node) {
struct callchain_list *call;
call = zalloc(sizeof(*call));
if (!call) {
perror("not enough memory for the code path tree");
return -ENOMEM;
}
call->ip = cursor_node->ip;
call->ms = cursor_node->ms;
call->ms.map = map__get(call->ms.map);
call->ms.maps = maps__get(call->ms.maps);
call->srcline = cursor_node->srcline;
if (cursor_node->branch) {
call->branch_count = 1;
if (cursor_node->branch_from) {
/*
* branch_from is set with value somewhere else
* to imply it's "to" of a branch.
*/
if (!call->brtype_stat) {
call->brtype_stat = zalloc(sizeof(*call->brtype_stat));
if (!call->brtype_stat) {
perror("not enough memory for the code path branch statistics");
zfree(&call->brtype_stat);
return -ENOMEM;
}
}
call->brtype_stat->branch_to = true;
if (cursor_node->branch_flags.predicted)
call->predicted_count = 1;
if (cursor_node->branch_flags.abort)
call->abort_count = 1;
branch_type_count(call->brtype_stat,
&cursor_node->branch_flags,
cursor_node->branch_from,
cursor_node->ip);
} else {
/*
* It's "from" of a branch
*/
if (call->brtype_stat && call->brtype_stat->branch_to)
call->brtype_stat->branch_to = false;
call->cycles_count =
cursor_node->branch_flags.cycles;
call->iter_count = cursor_node->nr_loop_iter;
call->iter_cycles = cursor_node->iter_cycles;
}
}
list_add_tail(&call->list, &node->val);
callchain_cursor_advance(cursor);
cursor_node = callchain_cursor_current(cursor);
}
return 0;
}
static struct callchain_node *
add_child(struct callchain_node *parent,
struct callchain_cursor *cursor,
u64 period)
{
struct callchain_node *new;
new = create_child(parent, false);
if (new == NULL)
return NULL;
if (fill_node(new, cursor) < 0) {
struct callchain_list *call, *tmp;
list_for_each_entry_safe(call, tmp, &new->val, list) {
list_del_init(&call->list);
map_symbol__exit(&call->ms);
zfree(&call->brtype_stat);
free(call);
}
free(new);
return NULL;
}
new->children_hit = 0;
new->hit = period;
new->children_count = 0;
new->count = 1;
return new;
}
enum match_result {
MATCH_ERROR = -1,
MATCH_EQ,
MATCH_LT,
MATCH_GT,
};
static enum match_result match_chain_strings(const char *left,
const char *right)
{
enum match_result ret = MATCH_EQ;
int cmp;
if (left && right)
cmp = strcmp(left, right);
else if (!left && right)
cmp = 1;
else if (left && !right)
cmp = -1;
else
return MATCH_ERROR;
if (cmp != 0)
ret = cmp < 0 ? MATCH_LT : MATCH_GT;
return ret;
}
/*
* We need to always use relative addresses because we're aggregating
* callchains from multiple threads, i.e. different address spaces, so
* comparing absolute addresses make no sense as a symbol in a DSO may end up
* in a different address when used in a different binary or even the same
* binary but with some sort of address randomization technique, thus we need
* to compare just relative addresses. -acme
*/
static enum match_result match_chain_dso_addresses(struct map *left_map, u64 left_ip,
struct map *right_map, u64 right_ip)
{
struct dso *left_dso = left_map ? map__dso(left_map) : NULL;
struct dso *right_dso = right_map ? map__dso(right_map) : NULL;
if (left_dso != right_dso)
return left_dso < right_dso ? MATCH_LT : MATCH_GT;
if (left_ip != right_ip)
return left_ip < right_ip ? MATCH_LT : MATCH_GT;
return MATCH_EQ;
}
static enum match_result match_chain(struct callchain_cursor_node *node,
struct callchain_list *cnode)
{
enum match_result match = MATCH_ERROR;
switch (callchain_param.key) {
case CCKEY_SRCLINE:
match = match_chain_strings(cnode->srcline, node->srcline);
if (match != MATCH_ERROR)
break;
/* otherwise fall-back to symbol-based comparison below */
fallthrough;
case CCKEY_FUNCTION:
if (node->ms.sym && cnode->ms.sym) {
/*
* Compare inlined frames based on their symbol name
* because different inlined frames will have the same
* symbol start. Otherwise do a faster comparison based
* on the symbol start address.
*/
if (cnode->ms.sym->inlined || node->ms.sym->inlined) {
match = match_chain_strings(cnode->ms.sym->name,
node->ms.sym->name);
if (match != MATCH_ERROR)
break;
} else {
match = match_chain_dso_addresses(cnode->ms.map, cnode->ms.sym->start,
node->ms.map, node->ms.sym->start);
break;
}
}
/* otherwise fall-back to IP-based comparison below */
fallthrough;
case CCKEY_ADDRESS:
default:
match = match_chain_dso_addresses(cnode->ms.map, cnode->ip, node->ms.map, node->ip);
break;
}
if (match == MATCH_EQ && node->branch) {
cnode->branch_count++;
if (node->branch_from) {
/*
* It's "to" of a branch
*/
if (!cnode->brtype_stat) {
cnode->brtype_stat = zalloc(sizeof(*cnode->brtype_stat));
if (!cnode->brtype_stat) {
perror("not enough memory for the code path branch statistics");
return MATCH_ERROR;
}
}
cnode->brtype_stat->branch_to = true;
if (node->branch_flags.predicted)
cnode->predicted_count++;
if (node->branch_flags.abort)
cnode->abort_count++;
branch_type_count(cnode->brtype_stat,
&node->branch_flags,
node->branch_from,
node->ip);
} else {
/*
* It's "from" of a branch
*/
if (cnode->brtype_stat && cnode->brtype_stat->branch_to)
cnode->brtype_stat->branch_to = false;
cnode->cycles_count += node->branch_flags.cycles;
cnode->iter_count += node->nr_loop_iter;
cnode->iter_cycles += node->iter_cycles;
cnode->from_count++;
}
}
return match;
}
/*
* Split the parent in two parts (a new child is created) and
* give a part of its callchain to the created child.
* Then create another child to host the given callchain of new branch
*/
static int
split_add_child(struct callchain_node *parent,
struct callchain_cursor *cursor,
struct callchain_list *to_split,
u64 idx_parents, u64 idx_local, u64 period)
{
struct callchain_node *new;
struct list_head *old_tail;
unsigned int idx_total = idx_parents + idx_local;
/* split */
new = create_child(parent, true);
if (new == NULL)
return -1;
/* split the callchain and move a part to the new child */
old_tail = parent->val.prev;
list_del_range(&to_split->list, old_tail);
new->val.next = &to_split->list;
new->val.prev = old_tail;
to_split->list.prev = &new->val;
old_tail->next = &new->val;
/* split the hits */
new->hit = parent->hit;
new->children_hit = parent->children_hit;
parent->children_hit = callchain_cumul_hits(new);
new->val_nr = parent->val_nr - idx_local;
parent->val_nr = idx_local;
new->count = parent->count;
new->children_count = parent->children_count;
parent->children_count = callchain_cumul_counts(new);
/* create a new child for the new branch if any */
if (idx_total < cursor->nr) {
struct callchain_node *first;
struct callchain_list *cnode;
struct callchain_cursor_node *node;
struct rb_node *p, **pp;
parent->hit = 0;
parent->children_hit += period;
parent->count = 0;
parent->children_count += 1;
node = callchain_cursor_current(cursor);
new = add_child(parent, cursor, period);
if (new == NULL)
return -1;
/*
* This is second child since we moved parent's children
* to new (first) child above.
*/
p = parent->rb_root_in.rb_node;
first = rb_entry(p, struct callchain_node, rb_node_in);
cnode = list_first_entry(&first->val, struct callchain_list,
list);
if (match_chain(node, cnode) == MATCH_LT)
pp = &p->rb_left;
else
pp = &p->rb_right;
rb_link_node(&new->rb_node_in, p, pp);
rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
} else {
parent->hit = period;
parent->count = 1;
}
return 0;
}
static enum match_result
append_chain(struct callchain_node *root,
struct callchain_cursor *cursor,
u64 period);
static int
append_chain_children(struct callchain_node *root,
struct callchain_cursor *cursor,
u64 period)
{
struct callchain_node *rnode;
struct callchain_cursor_node *node;
struct rb_node **p = &root->rb_root_in.rb_node;
struct rb_node *parent = NULL;
node = callchain_cursor_current(cursor);
if (!node)
return -1;
/* lookup in children */
while (*p) {
enum match_result ret;
parent = *p;
rnode = rb_entry(parent, struct callchain_node, rb_node_in);
/* If at least first entry matches, rely to children */
ret = append_chain(rnode, cursor, period);
if (ret == MATCH_EQ)
goto inc_children_hit;
if (ret == MATCH_ERROR)
return -1;
if (ret == MATCH_LT)
p = &parent->rb_left;
else
p = &parent->rb_right;
}
/* nothing in children, add to the current node */
rnode = add_child(root, cursor, period);
if (rnode == NULL)
return -1;
rb_link_node(&rnode->rb_node_in, parent, p);
rb_insert_color(&rnode->rb_node_in, &root->rb_root_in);
inc_children_hit:
root->children_hit += period;
root->children_count++;
return 0;
}
static enum match_result
append_chain(struct callchain_node *root,
struct callchain_cursor *cursor,
u64 period)
{
struct callchain_list *cnode;
u64 start = cursor->pos;
bool found = false;
u64 matches;
enum match_result cmp = MATCH_ERROR;
/*
* Lookup in the current node
* If we have a symbol, then compare the start to match
* anywhere inside a function, unless function
* mode is disabled.
*/
list_for_each_entry(cnode, &root->val, list) {
struct callchain_cursor_node *node;
node = callchain_cursor_current(cursor);
if (!node)
break;
cmp = match_chain(node, cnode);
if (cmp != MATCH_EQ)
break;
found = true;
callchain_cursor_advance(cursor);
}
/* matches not, relay no the parent */
if (!found) {
WARN_ONCE(cmp == MATCH_ERROR, "Chain comparison error\n");
return cmp;
}
matches = cursor->pos - start;
/* we match only a part of the node. Split it and add the new chain */
if (matches < root->val_nr) {
if (split_add_child(root, cursor, cnode, start, matches,
period) < 0)
return MATCH_ERROR;
return MATCH_EQ;
}
/* we match 100% of the path, increment the hit */
if (matches == root->val_nr && cursor->pos == cursor->nr) {
root->hit += period;
root->count++;
return MATCH_EQ;
}
/* We match the node and still have a part remaining */
if (append_chain_children(root, cursor, period) < 0)
return MATCH_ERROR;
return MATCH_EQ;
}
int callchain_append(struct callchain_root *root,
struct callchain_cursor *cursor,
u64 period)
{
if (cursor == NULL)
return -1;
if (!cursor->nr)
return 0;
callchain_cursor_commit(cursor);
if (append_chain_children(&root->node, cursor, period) < 0)
return -1;
if (cursor->nr > root->max_depth)
root->max_depth = cursor->nr;
return 0;
}
static int
merge_chain_branch(struct callchain_cursor *cursor,
struct callchain_node *dst, struct callchain_node *src)
{
struct callchain_cursor_node **old_last = cursor->last;
struct callchain_node *child;
struct callchain_list *list, *next_list;
struct rb_node *n;
int old_pos = cursor->nr;
int err = 0;
list_for_each_entry_safe(list, next_list, &src->val, list) {
struct map_symbol ms = {
.maps = maps__get(list->ms.maps),
.map = map__get(list->ms.map),
};
callchain_cursor_append(cursor, list->ip, &ms, false, NULL, 0, 0, 0, list->srcline);
list_del_init(&list->list);
map_symbol__exit(&ms);
map_symbol__exit(&list->ms);
zfree(&list->brtype_stat);
free(list);
}
if (src->hit) {
callchain_cursor_commit(cursor);
if (append_chain_children(dst, cursor, src->hit) < 0)
return -1;
}
n = rb_first(&src->rb_root_in);
while (n) {
child = container_of(n, struct callchain_node, rb_node_in);
n = rb_next(n);
rb_erase(&child->rb_node_in, &src->rb_root_in);
err = merge_chain_branch(cursor, dst, child);
if (err)
break;
free(child);
}
cursor->nr = old_pos;
cursor->last = old_last;
return err;
}
int callchain_merge(struct callchain_cursor *cursor,
struct callchain_root *dst, struct callchain_root *src)
{
return merge_chain_branch(cursor, &dst->node, &src->node);
}
int callchain_cursor_append(struct callchain_cursor *cursor,
u64 ip, struct map_symbol *ms,
bool branch, struct branch_flags *flags,
int nr_loop_iter, u64 iter_cycles, u64 branch_from,
const char *srcline)
{
struct callchain_cursor_node *node = *cursor->last;
if (!node) {
node = calloc(1, sizeof(*node));
if (!node)
return -ENOMEM;
*cursor->last = node;
}
node->ip = ip;
map_symbol__exit(&node->ms);
node->ms = *ms;
node->ms.maps = maps__get(ms->maps);
node->ms.map = map__get(ms->map);
node->branch = branch;
node->nr_loop_iter = nr_loop_iter;
node->iter_cycles = iter_cycles;
node->srcline = srcline;
if (flags)
memcpy(&node->branch_flags, flags,
sizeof(struct branch_flags));
node->branch_from = branch_from;
cursor->nr++;
cursor->last = &node->next;
return 0;
}
int sample__resolve_callchain(struct perf_sample *sample,
struct callchain_cursor *cursor, struct symbol **parent,
struct evsel *evsel, struct addr_location *al,
int max_stack)
{
if (sample->callchain == NULL && !symbol_conf.show_branchflag_count)
return 0;
if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain ||
perf_hpp_list.parent || symbol_conf.show_branchflag_count) {
return thread__resolve_callchain(al->thread, cursor, evsel, sample,
parent, al, max_stack);
}
return 0;
}
int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample)
{
if ((!symbol_conf.use_callchain || sample->callchain == NULL) &&
!symbol_conf.show_branchflag_count)
return 0;
return callchain_append(he->callchain, get_tls_callchain_cursor(), sample->period);
}
int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
bool hide_unresolved)
{
struct machine *machine = node->ms.maps ? maps__machine(node->ms.maps) : NULL;
maps__put(al->maps);
al->maps = maps__get(node->ms.maps);
map__put(al->map);
al->map = map__get(node->ms.map);
al->sym = node->ms.sym;
al->srcline = node->srcline;
al->addr = node->ip;
if (al->sym == NULL) {
if (hide_unresolved)
return 0;
if (al->map == NULL)
goto out;
}
if (maps__equal(al->maps, machine__kernel_maps(machine))) {
if (machine__is_host(machine)) {
al->cpumode = PERF_RECORD_MISC_KERNEL;
al->level = 'k';
} else {
al->cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
al->level = 'g';
}
} else {
if (machine__is_host(machine)) {
al->cpumode = PERF_RECORD_MISC_USER;
al->level = '.';
} else if (perf_guest) {
al->cpumode = PERF_RECORD_MISC_GUEST_USER;
al->level = 'u';
} else {
al->cpumode = PERF_RECORD_MISC_HYPERVISOR;
al->level = 'H';
}
}
out:
return 1;
}
char *callchain_list__sym_name(struct callchain_list *cl,
char *bf, size_t bfsize, bool show_dso)
{
bool show_addr = callchain_param.key == CCKEY_ADDRESS;
bool show_srcline = show_addr || callchain_param.key == CCKEY_SRCLINE;
int printed;
if (cl->ms.sym) {
const char *inlined = cl->ms.sym->inlined ? " (inlined)" : "";
if (show_srcline && cl->srcline)
printed = scnprintf(bf, bfsize, "%s %s%s",
cl->ms.sym->name, cl->srcline,
inlined);
else
printed = scnprintf(bf, bfsize, "%s%s",
cl->ms.sym->name, inlined);
} else
printed = scnprintf(bf, bfsize, "%#" PRIx64, cl->ip);
if (show_dso)
scnprintf(bf + printed, bfsize - printed, " %s",
cl->ms.map ?
dso__short_name(map__dso(cl->ms.map)) :
"unknown");
return bf;
}
char *callchain_node__scnprintf_value(struct callchain_node *node,
char *bf, size_t bfsize, u64 total)
{
double percent = 0.0;
u64 period = callchain_cumul_hits(node);
unsigned count = callchain_cumul_counts(node);
if (callchain_param.mode == CHAIN_FOLDED) {
period = node->hit;
count = node->count;
}
switch (callchain_param.value) {
case CCVAL_PERIOD:
scnprintf(bf, bfsize, "%"PRIu64, period);
break;
case CCVAL_COUNT:
scnprintf(bf, bfsize, "%u", count);
break;
case CCVAL_PERCENT:
default:
if (total)
percent = period * 100.0 / total;
scnprintf(bf, bfsize, "%.2f%%", percent);
break;
}
return bf;
}
int callchain_node__fprintf_value(struct callchain_node *node,
FILE *fp, u64 total)
{
double percent = 0.0;
u64 period = callchain_cumul_hits(node);
unsigned count = callchain_cumul_counts(node);
if (callchain_param.mode == CHAIN_FOLDED) {
period = node->hit;
count = node->count;
}
switch (callchain_param.value) {
case CCVAL_PERIOD:
return fprintf(fp, "%"PRIu64, period);
case CCVAL_COUNT:
return fprintf(fp, "%u", count);
case CCVAL_PERCENT:
default:
if (total)
percent = period * 100.0 / total;
return percent_color_fprintf(fp, "%.2f%%", percent);
}
return 0;
}
static void callchain_counts_value(struct callchain_node *node,
u64 *branch_count, u64 *predicted_count,
u64 *abort_count, u64 *cycles_count)
{
struct callchain_list *clist;
list_for_each_entry(clist, &node->val, list) {
if (branch_count)
*branch_count += clist->branch_count;
if (predicted_count)
*predicted_count += clist->predicted_count;
if (abort_count)
*abort_count += clist->abort_count;
if (cycles_count)
*cycles_count += clist->cycles_count;
}
}
static int callchain_node_branch_counts_cumul(struct callchain_node *node,
u64 *branch_count,
u64 *predicted_count,
u64 *abort_count,
u64 *cycles_count)
{
struct callchain_node *child;
struct rb_node *n;
n = rb_first(&node->rb_root_in);
while (n) {
child = rb_entry(n, struct callchain_node, rb_node_in);
n = rb_next(n);
callchain_node_branch_counts_cumul(child, branch_count,
predicted_count,
abort_count,
cycles_count);
callchain_counts_value(child, branch_count,
predicted_count, abort_count,
cycles_count);
}
return 0;
}
int callchain_branch_counts(struct callchain_root *root,
u64 *branch_count, u64 *predicted_count,
u64 *abort_count, u64 *cycles_count)
{
if (branch_count)
*branch_count = 0;
if (predicted_count)
*predicted_count = 0;
if (abort_count)
*abort_count = 0;
if (cycles_count)
*cycles_count = 0;
return callchain_node_branch_counts_cumul(&root->node,
branch_count,
predicted_count,
abort_count,
cycles_count);
}
static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int bfsize)
{
return scnprintf(bf, bfsize, "%s%s:%" PRId64 "", (idx) ? " " : " (", str, value);
}
static int count_float_printf(int idx, const char *str, float value,
char *bf, int bfsize, float threshold)
{
if (threshold != 0.0 && value < threshold)
return 0;
return scnprintf(bf, bfsize, "%s%s:%.1f%%", (idx) ? " " : " (", str, value);
}
static int branch_to_str(char *bf, int bfsize,
u64 branch_count, u64 predicted_count,
u64 abort_count,
const struct branch_type_stat *brtype_stat)
{
int printed, i = 0;
printed = branch_type_str(brtype_stat, bf, bfsize);
if (printed)
i++;
if (predicted_count < branch_count) {
printed += count_float_printf(i++, "predicted",
predicted_count * 100.0 / branch_count,
bf + printed, bfsize - printed, 0.0);
}
if (abort_count) {
printed += count_float_printf(i++, "abort",
abort_count * 100.0 / branch_count,
bf + printed, bfsize - printed, 0.1);
}
if (i)
printed += scnprintf(bf + printed, bfsize - printed, ")");
return printed;
}
static int branch_from_str(char *bf, int bfsize,
u64 branch_count,
u64 cycles_count, u64 iter_count,
u64 iter_cycles, u64 from_count)
{
int printed = 0, i = 0;
u64 cycles, v = 0;
cycles = cycles_count / branch_count;
if (cycles) {
printed += count_pri64_printf(i++, "cycles",
cycles,
bf + printed, bfsize - printed);
}
if (iter_count && from_count) {
v = iter_count / from_count;
if (v) {
printed += count_pri64_printf(i++, "iter",
v, bf + printed, bfsize - printed);
printed += count_pri64_printf(i++, "avg_cycles",
iter_cycles / iter_count,
bf + printed, bfsize - printed);
}
}
if (i)
printed += scnprintf(bf + printed, bfsize - printed, ")");
return printed;
}
static int counts_str_build(char *bf, int bfsize,
u64 branch_count, u64 predicted_count,
u64 abort_count, u64 cycles_count,
u64 iter_count, u64 iter_cycles,
u64 from_count,
const struct branch_type_stat *brtype_stat)
{
int printed;
if (branch_count == 0)
return scnprintf(bf, bfsize, " (calltrace)");
if (brtype_stat->branch_to) {
printed = branch_to_str(bf, bfsize, branch_count,
predicted_count, abort_count, brtype_stat);
} else {
printed = branch_from_str(bf, bfsize, branch_count,
cycles_count, iter_count, iter_cycles,
from_count);
}
if (!printed)
bf[0] = 0;
return printed;
}
static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
u64 branch_count, u64 predicted_count,
u64 abort_count, u64 cycles_count,
u64 iter_count, u64 iter_cycles,
u64 from_count,
const struct branch_type_stat *brtype_stat)
{
char str[256];
counts_str_build(str, sizeof(str), branch_count,
predicted_count, abort_count, cycles_count,
iter_count, iter_cycles, from_count, brtype_stat);
if (fp)
return fprintf(fp, "%s", str);
return scnprintf(bf, bfsize, "%s", str);
}
int callchain_list_counts__printf_value(struct callchain_list *clist,
FILE *fp, char *bf, int bfsize)
{
static const struct branch_type_stat empty_brtype_stat = {};
const struct branch_type_stat *brtype_stat;
u64 branch_count, predicted_count;
u64 abort_count, cycles_count;
u64 iter_count, iter_cycles;
u64 from_count;
brtype_stat = clist->brtype_stat ?: &empty_brtype_stat;
branch_count = clist->branch_count;
predicted_count = clist->predicted_count;
abort_count = clist->abort_count;
cycles_count = clist->cycles_count;
iter_count = clist->iter_count;
iter_cycles = clist->iter_cycles;
from_count = clist->from_count;
return callchain_counts_printf(fp, bf, bfsize, branch_count,
predicted_count, abort_count,
cycles_count, iter_count, iter_cycles,
from_count, brtype_stat);
}
static void free_callchain_node(struct callchain_node *node)
{
struct callchain_list *list, *tmp;
struct callchain_node *child;
struct rb_node *n;
list_for_each_entry_safe(list, tmp, &node->parent_val, list) {
list_del_init(&list->list);
map_symbol__exit(&list->ms);
zfree(&list->brtype_stat);
free(list);
}
list_for_each_entry_safe(list, tmp, &node->val, list) {
list_del_init(&list->list);
map_symbol__exit(&list->ms);
zfree(&list->brtype_stat);
free(list);
}
n = rb_first(&node->rb_root_in);
while (n) {
child = container_of(n, struct callchain_node, rb_node_in);
n = rb_next(n);
rb_erase(&child->rb_node_in, &node->rb_root_in);
free_callchain_node(child);
free(child);
}
}
void free_callchain(struct callchain_root *root)
{
if (!symbol_conf.use_callchain)
return;
free_callchain_node(&root->node);
}
static u64 decay_callchain_node(struct callchain_node *node)
{
struct callchain_node *child;
struct rb_node *n;
u64 child_hits = 0;
n = rb_first(&node->rb_root_in);
while (n) {
child = container_of(n, struct callchain_node, rb_node_in);
child_hits += decay_callchain_node(child);
n = rb_next(n);
}
node->hit = (node->hit * 7) / 8;
node->children_hit = child_hits;
return node->hit;
}
void decay_callchain(struct callchain_root *root)
{
if (!symbol_conf.use_callchain)
return;
decay_callchain_node(&root->node);
}
int callchain_node__make_parent_list(struct callchain_node *node)
{
struct callchain_node *parent = node->parent;
struct callchain_list *chain, *new;
LIST_HEAD(head);
while (parent) {
list_for_each_entry_reverse(chain, &parent->val, list) {
new = malloc(sizeof(*new));
if (new == NULL)
goto out;
*new = *chain;
new->has_children = false;
new->ms.map = map__get(new->ms.map);
list_add_tail(&new->list, &head);
}
parent = parent->parent;
}
list_for_each_entry_safe_reverse(chain, new, &head, list)
list_move_tail(&chain->list, &node->parent_val);
if (!list_empty(&node->parent_val)) {
chain = list_first_entry(&node->parent_val, struct callchain_list, list);
chain->has_children = rb_prev(&node->rb_node) || rb_next(&node->rb_node);
chain = list_first_entry(&node->val, struct callchain_list, list);
chain->has_children = false;
}
return 0;
out:
list_for_each_entry_safe(chain, new, &head, list) {
list_del_init(&chain->list);
map_symbol__exit(&chain->ms);
zfree(&chain->brtype_stat);
free(chain);
}
return -ENOMEM;
}
static void callchain_cursor__delete(void *vcursor)
{
struct callchain_cursor *cursor = vcursor;
struct callchain_cursor_node *node, *next;
callchain_cursor_reset(cursor);
for (node = cursor->first; node != NULL; node = next) {
next = node->next;
free(node);
}
free(cursor);
}
static void init_callchain_cursor_key(void)
{
if (pthread_key_create(&callchain_cursor, callchain_cursor__delete)) {
pr_err("callchain cursor creation failed");
abort();
}
}
struct callchain_cursor *get_tls_callchain_cursor(void)
{
static pthread_once_t once_control = PTHREAD_ONCE_INIT;
struct callchain_cursor *cursor;
pthread_once(&once_control, init_callchain_cursor_key);
cursor = pthread_getspecific(callchain_cursor);
if (!cursor) {
cursor = zalloc(sizeof(*cursor));
if (!cursor)
pr_debug3("%s: not enough memory\n", __func__);
pthread_setspecific(callchain_cursor, cursor);
}
return cursor;
}
int callchain_cursor__copy(struct callchain_cursor *dst,
struct callchain_cursor *src)
{
int rc = 0;
callchain_cursor_reset(dst);
callchain_cursor_commit(src);
while (true) {
struct callchain_cursor_node *node;
node = callchain_cursor_current(src);
if (node == NULL)
break;
rc = callchain_cursor_append(dst, node->ip, &node->ms,
node->branch, &node->branch_flags,
node->nr_loop_iter,
node->iter_cycles,
node->branch_from, node->srcline);
if (rc)
break;
callchain_cursor_advance(src);
}
return rc;
}
/*
* Initialize a cursor before adding entries inside, but keep
* the previously allocated entries as a cache.
*/
void callchain_cursor_reset(struct callchain_cursor *cursor)
{
struct callchain_cursor_node *node;
cursor->nr = 0;
cursor->last = &cursor->first;
for (node = cursor->first; node != NULL; node = node->next)
map_symbol__exit(&node->ms);
}
void callchain_param_setup(u64 sample_type, const char *arch)
{
if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain) {
if ((sample_type & PERF_SAMPLE_REGS_USER) &&
(sample_type & PERF_SAMPLE_STACK_USER)) {
callchain_param.record_mode = CALLCHAIN_DWARF;
dwarf_callchain_users = true;
} else if (sample_type & PERF_SAMPLE_BRANCH_STACK)
callchain_param.record_mode = CALLCHAIN_LBR;
else
callchain_param.record_mode = CALLCHAIN_FP;
}
/*
* It's necessary to use libunwind to reliably determine the caller of
* a leaf function on aarch64, as otherwise we cannot know whether to
* start from the LR or FP.
*
* Always starting from the LR can result in duplicate or entirely
* erroneous entries. Always skipping the LR and starting from the FP
* can result in missing entries.
*/
if (callchain_param.record_mode == CALLCHAIN_FP && !strcmp(arch, "arm64"))
dwarf_callchain_users = true;
}
static bool chain_match(struct callchain_list *base_chain,
struct callchain_list *pair_chain)
{
enum match_result match;
match = match_chain_strings(base_chain->srcline,
pair_chain->srcline);
if (match != MATCH_ERROR)
return match == MATCH_EQ;
match = match_chain_dso_addresses(base_chain->ms.map,
base_chain->ip,
pair_chain->ms.map,
pair_chain->ip);
return match == MATCH_EQ;
}
bool callchain_cnode_matched(struct callchain_node *base_cnode,
struct callchain_node *pair_cnode)
{
struct callchain_list *base_chain, *pair_chain;
bool match = false;
pair_chain = list_first_entry(&pair_cnode->val,
struct callchain_list,
list);
list_for_each_entry(base_chain, &base_cnode->val, list) {
if (&pair_chain->list == &pair_cnode->val)
return false;
if (!base_chain->srcline || !pair_chain->srcline) {
pair_chain = list_next_entry(pair_chain, list);
continue;
}
match = chain_match(base_chain, pair_chain);
if (!match)
return false;
pair_chain = list_next_entry(pair_chain, list);
}
/*
* Say chain1 is ABC, chain2 is ABCD, we consider they are
* not fully matched.
*/
if (pair_chain && (&pair_chain->list != &pair_cnode->val))
return false;
return match;
}
static u64 count_callchain_hits(struct hist_entry *he)
{
struct rb_root *root = &he->sorted_chain;
struct rb_node *rb_node = rb_first(root);
struct callchain_node *node;
u64 chain_hits = 0;
while (rb_node) {
node = rb_entry(rb_node, struct callchain_node, rb_node);
chain_hits += node->hit;
rb_node = rb_next(rb_node);
}
return chain_hits;
}
u64 callchain_total_hits(struct hists *hists)
{
struct rb_node *next = rb_first_cached(&hists->entries);
u64 chain_hits = 0;
while (next) {
struct hist_entry *he = rb_entry(next, struct hist_entry,
rb_node);
chain_hits += count_callchain_hits(he);
next = rb_next(&he->rb_node);
}
return chain_hits;
}
s64 callchain_avg_cycles(struct callchain_node *cnode)
{
struct callchain_list *chain;
s64 cycles = 0;
list_for_each_entry(chain, &cnode->val, list) {
if (chain->srcline && chain->branch_count)
cycles += chain->cycles_count / chain->branch_count;
}
return cycles;
}
int sample__for_each_callchain_node(struct thread *thread, struct evsel *evsel,
struct perf_sample *sample, int max_stack,
bool symbols, callchain_iter_fn cb, void *data)
{
struct callchain_cursor *cursor = get_tls_callchain_cursor();
int ret;
if (!cursor)
return -ENOMEM;
/* Fill in the callchain. */
ret = __thread__resolve_callchain(thread, cursor, evsel, sample,
/*parent=*/NULL, /*root_al=*/NULL,
max_stack, symbols);
if (ret)
return ret;
/* Switch from writing the callchain to reading it. */
callchain_cursor_commit(cursor);
while (1) {
struct callchain_cursor_node *node = callchain_cursor_current(cursor);
if (!node)
break;
ret = cb(node, data);
if (ret)
return ret;
callchain_cursor_advance(cursor);
}
return 0;
}
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