https://github.com/torvalds/linux
Tip revision: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 authored by Linus Torvalds on 09 July 2023, 20:53:13 UTC
Linux 6.5-rc1
Linux 6.5-rc1
Tip revision: 06c2afb
builtin-lock.c
// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <inttypes.h>
#include "builtin.h"
#include "perf.h"
#include "util/evlist.h" // for struct evsel_str_handler
#include "util/evsel.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"
#include "util/target.h"
#include "util/callchain.h"
#include "util/lock-contention.h"
#include "util/bpf_skel/lock_data.h"
#include <subcmd/pager.h>
#include <subcmd/parse-options.h>
#include "util/trace-event.h"
#include "util/tracepoint.h"
#include "util/debug.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/data.h"
#include "util/string2.h"
#include "util/map.h"
#include "util/util.h"
#include <stdio.h>
#include <sys/types.h>
#include <sys/prctl.h>
#include <semaphore.h>
#include <math.h>
#include <limits.h>
#include <ctype.h>
#include <linux/list.h>
#include <linux/hash.h>
#include <linux/kernel.h>
#include <linux/zalloc.h>
#include <linux/err.h>
#include <linux/stringify.h>
static struct perf_session *session;
static struct target target;
/* based on kernel/lockdep.c */
#define LOCKHASH_BITS 12
#define LOCKHASH_SIZE (1UL << LOCKHASH_BITS)
static struct hlist_head *lockhash_table;
#define __lockhashfn(key) hash_long((unsigned long)key, LOCKHASH_BITS)
#define lockhashentry(key) (lockhash_table + __lockhashfn((key)))
static struct rb_root thread_stats;
static bool combine_locks;
static bool show_thread_stats;
static bool show_lock_addrs;
static bool show_lock_owner;
static bool use_bpf;
static unsigned long bpf_map_entries = MAX_ENTRIES;
static int max_stack_depth = CONTENTION_STACK_DEPTH;
static int stack_skip = CONTENTION_STACK_SKIP;
static int print_nr_entries = INT_MAX / 2;
static LIST_HEAD(callstack_filters);
static const char *output_name = NULL;
static FILE *lock_output;
struct callstack_filter {
struct list_head list;
char name[];
};
static struct lock_filter filters;
static enum lock_aggr_mode aggr_mode = LOCK_AGGR_ADDR;
static bool needs_callstack(void)
{
return !list_empty(&callstack_filters);
}
static struct thread_stat *thread_stat_find(u32 tid)
{
struct rb_node *node;
struct thread_stat *st;
node = thread_stats.rb_node;
while (node) {
st = container_of(node, struct thread_stat, rb);
if (st->tid == tid)
return st;
else if (tid < st->tid)
node = node->rb_left;
else
node = node->rb_right;
}
return NULL;
}
static void thread_stat_insert(struct thread_stat *new)
{
struct rb_node **rb = &thread_stats.rb_node;
struct rb_node *parent = NULL;
struct thread_stat *p;
while (*rb) {
p = container_of(*rb, struct thread_stat, rb);
parent = *rb;
if (new->tid < p->tid)
rb = &(*rb)->rb_left;
else if (new->tid > p->tid)
rb = &(*rb)->rb_right;
else
BUG_ON("inserting invalid thread_stat\n");
}
rb_link_node(&new->rb, parent, rb);
rb_insert_color(&new->rb, &thread_stats);
}
static struct thread_stat *thread_stat_findnew_after_first(u32 tid)
{
struct thread_stat *st;
st = thread_stat_find(tid);
if (st)
return st;
st = zalloc(sizeof(struct thread_stat));
if (!st) {
pr_err("memory allocation failed\n");
return NULL;
}
st->tid = tid;
INIT_LIST_HEAD(&st->seq_list);
thread_stat_insert(st);
return st;
}
static struct thread_stat *thread_stat_findnew_first(u32 tid);
static struct thread_stat *(*thread_stat_findnew)(u32 tid) =
thread_stat_findnew_first;
static struct thread_stat *thread_stat_findnew_first(u32 tid)
{
struct thread_stat *st;
st = zalloc(sizeof(struct thread_stat));
if (!st) {
pr_err("memory allocation failed\n");
return NULL;
}
st->tid = tid;
INIT_LIST_HEAD(&st->seq_list);
rb_link_node(&st->rb, NULL, &thread_stats.rb_node);
rb_insert_color(&st->rb, &thread_stats);
thread_stat_findnew = thread_stat_findnew_after_first;
return st;
}
/* build simple key function one is bigger than two */
#define SINGLE_KEY(member) \
static int lock_stat_key_ ## member(struct lock_stat *one, \
struct lock_stat *two) \
{ \
return one->member > two->member; \
}
SINGLE_KEY(nr_acquired)
SINGLE_KEY(nr_contended)
SINGLE_KEY(avg_wait_time)
SINGLE_KEY(wait_time_total)
SINGLE_KEY(wait_time_max)
static int lock_stat_key_wait_time_min(struct lock_stat *one,
struct lock_stat *two)
{
u64 s1 = one->wait_time_min;
u64 s2 = two->wait_time_min;
if (s1 == ULLONG_MAX)
s1 = 0;
if (s2 == ULLONG_MAX)
s2 = 0;
return s1 > s2;
}
struct lock_key {
/*
* name: the value for specify by user
* this should be simpler than raw name of member
* e.g. nr_acquired -> acquired, wait_time_total -> wait_total
*/
const char *name;
/* header: the string printed on the header line */
const char *header;
/* len: the printing width of the field */
int len;
/* key: a pointer to function to compare two lock stats for sorting */
int (*key)(struct lock_stat*, struct lock_stat*);
/* print: a pointer to function to print a given lock stats */
void (*print)(struct lock_key*, struct lock_stat*);
/* list: list entry to link this */
struct list_head list;
};
static void lock_stat_key_print_time(unsigned long long nsec, int len)
{
static const struct {
float base;
const char *unit;
} table[] = {
{ 1e9 * 3600, "h " },
{ 1e9 * 60, "m " },
{ 1e9, "s " },
{ 1e6, "ms" },
{ 1e3, "us" },
{ 0, NULL },
};
/* for CSV output */
if (len == 0) {
fprintf(lock_output, "%llu", nsec);
return;
}
for (int i = 0; table[i].unit; i++) {
if (nsec < table[i].base)
continue;
fprintf(lock_output, "%*.2f %s", len - 3, nsec / table[i].base, table[i].unit);
return;
}
fprintf(lock_output, "%*llu %s", len - 3, nsec, "ns");
}
#define PRINT_KEY(member) \
static void lock_stat_key_print_ ## member(struct lock_key *key, \
struct lock_stat *ls) \
{ \
fprintf(lock_output, "%*llu", key->len, (unsigned long long)ls->member);\
}
#define PRINT_TIME(member) \
static void lock_stat_key_print_ ## member(struct lock_key *key, \
struct lock_stat *ls) \
{ \
lock_stat_key_print_time((unsigned long long)ls->member, key->len); \
}
PRINT_KEY(nr_acquired)
PRINT_KEY(nr_contended)
PRINT_TIME(avg_wait_time)
PRINT_TIME(wait_time_total)
PRINT_TIME(wait_time_max)
static void lock_stat_key_print_wait_time_min(struct lock_key *key,
struct lock_stat *ls)
{
u64 wait_time = ls->wait_time_min;
if (wait_time == ULLONG_MAX)
wait_time = 0;
lock_stat_key_print_time(wait_time, key->len);
}
static const char *sort_key = "acquired";
static int (*compare)(struct lock_stat *, struct lock_stat *);
static struct rb_root sorted; /* place to store intermediate data */
static struct rb_root result; /* place to store sorted data */
static LIST_HEAD(lock_keys);
static const char *output_fields;
#define DEF_KEY_LOCK(name, header, fn_suffix, len) \
{ #name, header, len, lock_stat_key_ ## fn_suffix, lock_stat_key_print_ ## fn_suffix, {} }
static struct lock_key report_keys[] = {
DEF_KEY_LOCK(acquired, "acquired", nr_acquired, 10),
DEF_KEY_LOCK(contended, "contended", nr_contended, 10),
DEF_KEY_LOCK(avg_wait, "avg wait", avg_wait_time, 12),
DEF_KEY_LOCK(wait_total, "total wait", wait_time_total, 12),
DEF_KEY_LOCK(wait_max, "max wait", wait_time_max, 12),
DEF_KEY_LOCK(wait_min, "min wait", wait_time_min, 12),
/* extra comparisons much complicated should be here */
{ }
};
static struct lock_key contention_keys[] = {
DEF_KEY_LOCK(contended, "contended", nr_contended, 10),
DEF_KEY_LOCK(wait_total, "total wait", wait_time_total, 12),
DEF_KEY_LOCK(wait_max, "max wait", wait_time_max, 12),
DEF_KEY_LOCK(wait_min, "min wait", wait_time_min, 12),
DEF_KEY_LOCK(avg_wait, "avg wait", avg_wait_time, 12),
/* extra comparisons much complicated should be here */
{ }
};
static int select_key(bool contention)
{
int i;
struct lock_key *keys = report_keys;
if (contention)
keys = contention_keys;
for (i = 0; keys[i].name; i++) {
if (!strcmp(keys[i].name, sort_key)) {
compare = keys[i].key;
/* selected key should be in the output fields */
if (list_empty(&keys[i].list))
list_add_tail(&keys[i].list, &lock_keys);
return 0;
}
}
pr_err("Unknown compare key: %s\n", sort_key);
return -1;
}
static int add_output_field(bool contention, char *name)
{
int i;
struct lock_key *keys = report_keys;
if (contention)
keys = contention_keys;
for (i = 0; keys[i].name; i++) {
if (strcmp(keys[i].name, name))
continue;
/* prevent double link */
if (list_empty(&keys[i].list))
list_add_tail(&keys[i].list, &lock_keys);
return 0;
}
pr_err("Unknown output field: %s\n", name);
return -1;
}
static int setup_output_field(bool contention, const char *str)
{
char *tok, *tmp, *orig;
int i, ret = 0;
struct lock_key *keys = report_keys;
if (contention)
keys = contention_keys;
/* no output field given: use all of them */
if (str == NULL) {
for (i = 0; keys[i].name; i++)
list_add_tail(&keys[i].list, &lock_keys);
return 0;
}
for (i = 0; keys[i].name; i++)
INIT_LIST_HEAD(&keys[i].list);
orig = tmp = strdup(str);
if (orig == NULL)
return -ENOMEM;
while ((tok = strsep(&tmp, ",")) != NULL){
ret = add_output_field(contention, tok);
if (ret < 0)
break;
}
free(orig);
return ret;
}
static void combine_lock_stats(struct lock_stat *st)
{
struct rb_node **rb = &sorted.rb_node;
struct rb_node *parent = NULL;
struct lock_stat *p;
int ret;
while (*rb) {
p = container_of(*rb, struct lock_stat, rb);
parent = *rb;
if (st->name && p->name)
ret = strcmp(st->name, p->name);
else
ret = !!st->name - !!p->name;
if (ret == 0) {
p->nr_acquired += st->nr_acquired;
p->nr_contended += st->nr_contended;
p->wait_time_total += st->wait_time_total;
if (p->nr_contended)
p->avg_wait_time = p->wait_time_total / p->nr_contended;
if (p->wait_time_min > st->wait_time_min)
p->wait_time_min = st->wait_time_min;
if (p->wait_time_max < st->wait_time_max)
p->wait_time_max = st->wait_time_max;
p->broken |= st->broken;
st->combined = 1;
return;
}
if (ret < 0)
rb = &(*rb)->rb_left;
else
rb = &(*rb)->rb_right;
}
rb_link_node(&st->rb, parent, rb);
rb_insert_color(&st->rb, &sorted);
}
static void insert_to_result(struct lock_stat *st,
int (*bigger)(struct lock_stat *, struct lock_stat *))
{
struct rb_node **rb = &result.rb_node;
struct rb_node *parent = NULL;
struct lock_stat *p;
if (combine_locks && st->combined)
return;
while (*rb) {
p = container_of(*rb, struct lock_stat, rb);
parent = *rb;
if (bigger(st, p))
rb = &(*rb)->rb_left;
else
rb = &(*rb)->rb_right;
}
rb_link_node(&st->rb, parent, rb);
rb_insert_color(&st->rb, &result);
}
/* returns left most element of result, and erase it */
static struct lock_stat *pop_from_result(void)
{
struct rb_node *node = result.rb_node;
if (!node)
return NULL;
while (node->rb_left)
node = node->rb_left;
rb_erase(node, &result);
return container_of(node, struct lock_stat, rb);
}
struct lock_stat *lock_stat_find(u64 addr)
{
struct hlist_head *entry = lockhashentry(addr);
struct lock_stat *ret;
hlist_for_each_entry(ret, entry, hash_entry) {
if (ret->addr == addr)
return ret;
}
return NULL;
}
struct lock_stat *lock_stat_findnew(u64 addr, const char *name, int flags)
{
struct hlist_head *entry = lockhashentry(addr);
struct lock_stat *ret, *new;
hlist_for_each_entry(ret, entry, hash_entry) {
if (ret->addr == addr)
return ret;
}
new = zalloc(sizeof(struct lock_stat));
if (!new)
goto alloc_failed;
new->addr = addr;
new->name = strdup(name);
if (!new->name) {
free(new);
goto alloc_failed;
}
new->flags = flags;
new->wait_time_min = ULLONG_MAX;
hlist_add_head(&new->hash_entry, entry);
return new;
alloc_failed:
pr_err("memory allocation failed\n");
return NULL;
}
bool match_callstack_filter(struct machine *machine, u64 *callstack)
{
struct map *kmap;
struct symbol *sym;
u64 ip;
if (list_empty(&callstack_filters))
return true;
for (int i = 0; i < max_stack_depth; i++) {
struct callstack_filter *filter;
if (!callstack || !callstack[i])
break;
ip = callstack[i];
sym = machine__find_kernel_symbol(machine, ip, &kmap);
if (sym == NULL)
continue;
list_for_each_entry(filter, &callstack_filters, list) {
if (strstr(sym->name, filter->name))
return true;
}
}
return false;
}
struct trace_lock_handler {
/* it's used on CONFIG_LOCKDEP */
int (*acquire_event)(struct evsel *evsel,
struct perf_sample *sample);
/* it's used on CONFIG_LOCKDEP && CONFIG_LOCK_STAT */
int (*acquired_event)(struct evsel *evsel,
struct perf_sample *sample);
/* it's used on CONFIG_LOCKDEP && CONFIG_LOCK_STAT */
int (*contended_event)(struct evsel *evsel,
struct perf_sample *sample);
/* it's used on CONFIG_LOCKDEP */
int (*release_event)(struct evsel *evsel,
struct perf_sample *sample);
/* it's used when CONFIG_LOCKDEP is off */
int (*contention_begin_event)(struct evsel *evsel,
struct perf_sample *sample);
/* it's used when CONFIG_LOCKDEP is off */
int (*contention_end_event)(struct evsel *evsel,
struct perf_sample *sample);
};
static struct lock_seq_stat *get_seq(struct thread_stat *ts, u64 addr)
{
struct lock_seq_stat *seq;
list_for_each_entry(seq, &ts->seq_list, list) {
if (seq->addr == addr)
return seq;
}
seq = zalloc(sizeof(struct lock_seq_stat));
if (!seq) {
pr_err("memory allocation failed\n");
return NULL;
}
seq->state = SEQ_STATE_UNINITIALIZED;
seq->addr = addr;
list_add(&seq->list, &ts->seq_list);
return seq;
}
enum broken_state {
BROKEN_ACQUIRE,
BROKEN_ACQUIRED,
BROKEN_CONTENDED,
BROKEN_RELEASE,
BROKEN_MAX,
};
static int bad_hist[BROKEN_MAX];
enum acquire_flags {
TRY_LOCK = 1,
READ_LOCK = 2,
};
static int get_key_by_aggr_mode_simple(u64 *key, u64 addr, u32 tid)
{
switch (aggr_mode) {
case LOCK_AGGR_ADDR:
*key = addr;
break;
case LOCK_AGGR_TASK:
*key = tid;
break;
case LOCK_AGGR_CALLER:
default:
pr_err("Invalid aggregation mode: %d\n", aggr_mode);
return -EINVAL;
}
return 0;
}
static u64 callchain_id(struct evsel *evsel, struct perf_sample *sample);
static int get_key_by_aggr_mode(u64 *key, u64 addr, struct evsel *evsel,
struct perf_sample *sample)
{
if (aggr_mode == LOCK_AGGR_CALLER) {
*key = callchain_id(evsel, sample);
return 0;
}
return get_key_by_aggr_mode_simple(key, addr, sample->tid);
}
static int report_lock_acquire_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
const char *name = evsel__strval(evsel, sample, "name");
u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
int flag = evsel__intval(evsel, sample, "flags");
u64 key;
int ret;
ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
if (ret < 0)
return ret;
ls = lock_stat_findnew(key, name, 0);
if (!ls)
return -ENOMEM;
ts = thread_stat_findnew(sample->tid);
if (!ts)
return -ENOMEM;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
case SEQ_STATE_RELEASED:
if (!flag) {
seq->state = SEQ_STATE_ACQUIRING;
} else {
if (flag & TRY_LOCK)
ls->nr_trylock++;
if (flag & READ_LOCK)
ls->nr_readlock++;
seq->state = SEQ_STATE_READ_ACQUIRED;
seq->read_count = 1;
ls->nr_acquired++;
}
break;
case SEQ_STATE_READ_ACQUIRED:
if (flag & READ_LOCK) {
seq->read_count++;
ls->nr_acquired++;
goto end;
} else {
goto broken;
}
break;
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_CONTENDED:
broken:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_ACQUIRE]++;
}
list_del_init(&seq->list);
free(seq);
goto end;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
ls->nr_acquire++;
seq->prev_event_time = sample->time;
end:
return 0;
}
static int report_lock_acquired_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
u64 contended_term;
const char *name = evsel__strval(evsel, sample, "name");
u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
u64 key;
int ret;
ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
if (ret < 0)
return ret;
ls = lock_stat_findnew(key, name, 0);
if (!ls)
return -ENOMEM;
ts = thread_stat_findnew(sample->tid);
if (!ts)
return -ENOMEM;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
/* orphan event, do nothing */
return 0;
case SEQ_STATE_ACQUIRING:
break;
case SEQ_STATE_CONTENDED:
contended_term = sample->time - seq->prev_event_time;
ls->wait_time_total += contended_term;
if (contended_term < ls->wait_time_min)
ls->wait_time_min = contended_term;
if (ls->wait_time_max < contended_term)
ls->wait_time_max = contended_term;
break;
case SEQ_STATE_RELEASED:
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_READ_ACQUIRED:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_ACQUIRED]++;
}
list_del_init(&seq->list);
free(seq);
goto end;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
seq->state = SEQ_STATE_ACQUIRED;
ls->nr_acquired++;
ls->avg_wait_time = ls->nr_contended ? ls->wait_time_total/ls->nr_contended : 0;
seq->prev_event_time = sample->time;
end:
return 0;
}
static int report_lock_contended_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
const char *name = evsel__strval(evsel, sample, "name");
u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
u64 key;
int ret;
ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
if (ret < 0)
return ret;
ls = lock_stat_findnew(key, name, 0);
if (!ls)
return -ENOMEM;
ts = thread_stat_findnew(sample->tid);
if (!ts)
return -ENOMEM;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
/* orphan event, do nothing */
return 0;
case SEQ_STATE_ACQUIRING:
break;
case SEQ_STATE_RELEASED:
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_READ_ACQUIRED:
case SEQ_STATE_CONTENDED:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_CONTENDED]++;
}
list_del_init(&seq->list);
free(seq);
goto end;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
seq->state = SEQ_STATE_CONTENDED;
ls->nr_contended++;
ls->avg_wait_time = ls->wait_time_total/ls->nr_contended;
seq->prev_event_time = sample->time;
end:
return 0;
}
static int report_lock_release_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
const char *name = evsel__strval(evsel, sample, "name");
u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
u64 key;
int ret;
ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
if (ret < 0)
return ret;
ls = lock_stat_findnew(key, name, 0);
if (!ls)
return -ENOMEM;
ts = thread_stat_findnew(sample->tid);
if (!ts)
return -ENOMEM;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
goto end;
case SEQ_STATE_ACQUIRED:
break;
case SEQ_STATE_READ_ACQUIRED:
seq->read_count--;
BUG_ON(seq->read_count < 0);
if (seq->read_count) {
ls->nr_release++;
goto end;
}
break;
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_CONTENDED:
case SEQ_STATE_RELEASED:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_RELEASE]++;
}
goto free_seq;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
ls->nr_release++;
free_seq:
list_del_init(&seq->list);
free(seq);
end:
return 0;
}
static int get_symbol_name_offset(struct map *map, struct symbol *sym, u64 ip,
char *buf, int size)
{
u64 offset;
if (map == NULL || sym == NULL) {
buf[0] = '\0';
return 0;
}
offset = map__map_ip(map, ip) - sym->start;
if (offset)
return scnprintf(buf, size, "%s+%#lx", sym->name, offset);
else
return strlcpy(buf, sym->name, size);
}
static int lock_contention_caller(struct evsel *evsel, struct perf_sample *sample,
char *buf, int size)
{
struct thread *thread;
struct callchain_cursor *cursor;
struct machine *machine = &session->machines.host;
struct symbol *sym;
int skip = 0;
int ret;
/* lock names will be replaced to task name later */
if (show_thread_stats)
return -1;
thread = machine__findnew_thread(machine, -1, sample->pid);
if (thread == NULL)
return -1;
cursor = get_tls_callchain_cursor();
/* use caller function name from the callchain */
ret = thread__resolve_callchain(thread, cursor, evsel, sample,
NULL, NULL, max_stack_depth);
if (ret != 0) {
thread__put(thread);
return -1;
}
callchain_cursor_commit(cursor);
thread__put(thread);
while (true) {
struct callchain_cursor_node *node;
node = callchain_cursor_current(cursor);
if (node == NULL)
break;
/* skip first few entries - for lock functions */
if (++skip <= stack_skip)
goto next;
sym = node->ms.sym;
if (sym && !machine__is_lock_function(machine, node->ip)) {
get_symbol_name_offset(node->ms.map, sym, node->ip,
buf, size);
return 0;
}
next:
callchain_cursor_advance(cursor);
}
return -1;
}
static u64 callchain_id(struct evsel *evsel, struct perf_sample *sample)
{
struct callchain_cursor *cursor;
struct machine *machine = &session->machines.host;
struct thread *thread;
u64 hash = 0;
int skip = 0;
int ret;
thread = machine__findnew_thread(machine, -1, sample->pid);
if (thread == NULL)
return -1;
cursor = get_tls_callchain_cursor();
/* use caller function name from the callchain */
ret = thread__resolve_callchain(thread, cursor, evsel, sample,
NULL, NULL, max_stack_depth);
thread__put(thread);
if (ret != 0)
return -1;
callchain_cursor_commit(cursor);
while (true) {
struct callchain_cursor_node *node;
node = callchain_cursor_current(cursor);
if (node == NULL)
break;
/* skip first few entries - for lock functions */
if (++skip <= stack_skip)
goto next;
if (node->ms.sym && machine__is_lock_function(machine, node->ip))
goto next;
hash ^= hash_long((unsigned long)node->ip, 64);
next:
callchain_cursor_advance(cursor);
}
return hash;
}
static u64 *get_callstack(struct perf_sample *sample, int max_stack)
{
u64 *callstack;
u64 i;
int c;
callstack = calloc(max_stack, sizeof(*callstack));
if (callstack == NULL)
return NULL;
for (i = 0, c = 0; i < sample->callchain->nr && c < max_stack; i++) {
u64 ip = sample->callchain->ips[i];
if (ip >= PERF_CONTEXT_MAX)
continue;
callstack[c++] = ip;
}
return callstack;
}
static int report_lock_contention_begin_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
u64 addr = evsel__intval(evsel, sample, "lock_addr");
unsigned int flags = evsel__intval(evsel, sample, "flags");
u64 key;
int i, ret;
static bool kmap_loaded;
struct machine *machine = &session->machines.host;
struct map *kmap;
struct symbol *sym;
ret = get_key_by_aggr_mode(&key, addr, evsel, sample);
if (ret < 0)
return ret;
if (!kmap_loaded) {
unsigned long *addrs;
/* make sure it loads the kernel map to find lock symbols */
map__load(machine__kernel_map(machine));
kmap_loaded = true;
/* convert (kernel) symbols to addresses */
for (i = 0; i < filters.nr_syms; i++) {
sym = machine__find_kernel_symbol_by_name(machine,
filters.syms[i],
&kmap);
if (sym == NULL) {
pr_warning("ignore unknown symbol: %s\n",
filters.syms[i]);
continue;
}
addrs = realloc(filters.addrs,
(filters.nr_addrs + 1) * sizeof(*addrs));
if (addrs == NULL) {
pr_warning("memory allocation failure\n");
return -ENOMEM;
}
addrs[filters.nr_addrs++] = map__unmap_ip(kmap, sym->start);
filters.addrs = addrs;
}
}
ls = lock_stat_find(key);
if (!ls) {
char buf[128];
const char *name = "";
switch (aggr_mode) {
case LOCK_AGGR_ADDR:
sym = machine__find_kernel_symbol(machine, key, &kmap);
if (sym)
name = sym->name;
break;
case LOCK_AGGR_CALLER:
name = buf;
if (lock_contention_caller(evsel, sample, buf, sizeof(buf)) < 0)
name = "Unknown";
break;
case LOCK_AGGR_TASK:
default:
break;
}
ls = lock_stat_findnew(key, name, flags);
if (!ls)
return -ENOMEM;
}
if (filters.nr_types) {
bool found = false;
for (i = 0; i < filters.nr_types; i++) {
if (flags == filters.types[i]) {
found = true;
break;
}
}
if (!found)
return 0;
}
if (filters.nr_addrs) {
bool found = false;
for (i = 0; i < filters.nr_addrs; i++) {
if (addr == filters.addrs[i]) {
found = true;
break;
}
}
if (!found)
return 0;
}
if (needs_callstack()) {
u64 *callstack = get_callstack(sample, max_stack_depth);
if (callstack == NULL)
return -ENOMEM;
if (!match_callstack_filter(machine, callstack)) {
free(callstack);
return 0;
}
if (ls->callstack == NULL)
ls->callstack = callstack;
else
free(callstack);
}
ts = thread_stat_findnew(sample->tid);
if (!ts)
return -ENOMEM;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
case SEQ_STATE_ACQUIRED:
break;
case SEQ_STATE_CONTENDED:
/*
* It can have nested contention begin with mutex spinning,
* then we would use the original contention begin event and
* ignore the second one.
*/
goto end;
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_READ_ACQUIRED:
case SEQ_STATE_RELEASED:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_CONTENDED]++;
}
list_del_init(&seq->list);
free(seq);
goto end;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
if (seq->state != SEQ_STATE_CONTENDED) {
seq->state = SEQ_STATE_CONTENDED;
seq->prev_event_time = sample->time;
ls->nr_contended++;
}
end:
return 0;
}
static int report_lock_contention_end_event(struct evsel *evsel,
struct perf_sample *sample)
{
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
u64 contended_term;
u64 addr = evsel__intval(evsel, sample, "lock_addr");
u64 key;
int ret;
ret = get_key_by_aggr_mode(&key, addr, evsel, sample);
if (ret < 0)
return ret;
ls = lock_stat_find(key);
if (!ls)
return 0;
ts = thread_stat_find(sample->tid);
if (!ts)
return 0;
seq = get_seq(ts, addr);
if (!seq)
return -ENOMEM;
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
goto end;
case SEQ_STATE_CONTENDED:
contended_term = sample->time - seq->prev_event_time;
ls->wait_time_total += contended_term;
if (contended_term < ls->wait_time_min)
ls->wait_time_min = contended_term;
if (ls->wait_time_max < contended_term)
ls->wait_time_max = contended_term;
break;
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_READ_ACQUIRED:
case SEQ_STATE_RELEASED:
/* broken lock sequence */
if (!ls->broken) {
ls->broken = 1;
bad_hist[BROKEN_ACQUIRED]++;
}
list_del_init(&seq->list);
free(seq);
goto end;
default:
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
seq->state = SEQ_STATE_ACQUIRED;
ls->nr_acquired++;
ls->avg_wait_time = ls->wait_time_total/ls->nr_acquired;
end:
return 0;
}
/* lock oriented handlers */
/* TODO: handlers for CPU oriented, thread oriented */
static struct trace_lock_handler report_lock_ops = {
.acquire_event = report_lock_acquire_event,
.acquired_event = report_lock_acquired_event,
.contended_event = report_lock_contended_event,
.release_event = report_lock_release_event,
.contention_begin_event = report_lock_contention_begin_event,
.contention_end_event = report_lock_contention_end_event,
};
static struct trace_lock_handler contention_lock_ops = {
.contention_begin_event = report_lock_contention_begin_event,
.contention_end_event = report_lock_contention_end_event,
};
static struct trace_lock_handler *trace_handler;
static int evsel__process_lock_acquire(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->acquire_event)
return trace_handler->acquire_event(evsel, sample);
return 0;
}
static int evsel__process_lock_acquired(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->acquired_event)
return trace_handler->acquired_event(evsel, sample);
return 0;
}
static int evsel__process_lock_contended(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->contended_event)
return trace_handler->contended_event(evsel, sample);
return 0;
}
static int evsel__process_lock_release(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->release_event)
return trace_handler->release_event(evsel, sample);
return 0;
}
static int evsel__process_contention_begin(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->contention_begin_event)
return trace_handler->contention_begin_event(evsel, sample);
return 0;
}
static int evsel__process_contention_end(struct evsel *evsel, struct perf_sample *sample)
{
if (trace_handler->contention_end_event)
return trace_handler->contention_end_event(evsel, sample);
return 0;
}
static void print_bad_events(int bad, int total)
{
/* Output for debug, this have to be removed */
int i;
int broken = 0;
const char *name[4] =
{ "acquire", "acquired", "contended", "release" };
for (i = 0; i < BROKEN_MAX; i++)
broken += bad_hist[i];
if (quiet || total == 0 || (broken == 0 && verbose <= 0))
return;
fprintf(lock_output, "\n=== output for debug ===\n\n");
fprintf(lock_output, "bad: %d, total: %d\n", bad, total);
fprintf(lock_output, "bad rate: %.2f %%\n", (double)bad / (double)total * 100);
fprintf(lock_output, "histogram of events caused bad sequence\n");
for (i = 0; i < BROKEN_MAX; i++)
fprintf(lock_output, " %10s: %d\n", name[i], bad_hist[i]);
}
/* TODO: various way to print, coloring, nano or milli sec */
static void print_result(void)
{
struct lock_stat *st;
struct lock_key *key;
char cut_name[20];
int bad, total, printed;
if (!quiet) {
fprintf(lock_output, "%20s ", "Name");
list_for_each_entry(key, &lock_keys, list)
fprintf(lock_output, "%*s ", key->len, key->header);
fprintf(lock_output, "\n\n");
}
bad = total = printed = 0;
while ((st = pop_from_result())) {
total++;
if (st->broken)
bad++;
if (!st->nr_acquired)
continue;
bzero(cut_name, 20);
if (strlen(st->name) < 20) {
/* output raw name */
const char *name = st->name;
if (show_thread_stats) {
struct thread *t;
/* st->addr contains tid of thread */
t = perf_session__findnew(session, st->addr);
name = thread__comm_str(t);
}
fprintf(lock_output, "%20s ", name);
} else {
strncpy(cut_name, st->name, 16);
cut_name[16] = '.';
cut_name[17] = '.';
cut_name[18] = '.';
cut_name[19] = '\0';
/* cut off name for saving output style */
fprintf(lock_output, "%20s ", cut_name);
}
list_for_each_entry(key, &lock_keys, list) {
key->print(key, st);
fprintf(lock_output, " ");
}
fprintf(lock_output, "\n");
if (++printed >= print_nr_entries)
break;
}
print_bad_events(bad, total);
}
static bool info_threads, info_map;
static void dump_threads(void)
{
struct thread_stat *st;
struct rb_node *node;
struct thread *t;
fprintf(lock_output, "%10s: comm\n", "Thread ID");
node = rb_first(&thread_stats);
while (node) {
st = container_of(node, struct thread_stat, rb);
t = perf_session__findnew(session, st->tid);
fprintf(lock_output, "%10d: %s\n", st->tid, thread__comm_str(t));
node = rb_next(node);
thread__put(t);
}
}
static int compare_maps(struct lock_stat *a, struct lock_stat *b)
{
int ret;
if (a->name && b->name)
ret = strcmp(a->name, b->name);
else
ret = !!a->name - !!b->name;
if (!ret)
return a->addr < b->addr;
else
return ret < 0;
}
static void dump_map(void)
{
unsigned int i;
struct lock_stat *st;
fprintf(lock_output, "Address of instance: name of class\n");
for (i = 0; i < LOCKHASH_SIZE; i++) {
hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
insert_to_result(st, compare_maps);
}
}
while ((st = pop_from_result()))
fprintf(lock_output, " %#llx: %s\n", (unsigned long long)st->addr, st->name);
}
static int dump_info(void)
{
int rc = 0;
if (info_threads)
dump_threads();
else if (info_map)
dump_map();
else {
rc = -1;
pr_err("Unknown type of information\n");
}
return rc;
}
static const struct evsel_str_handler lock_tracepoints[] = {
{ "lock:lock_acquire", evsel__process_lock_acquire, }, /* CONFIG_LOCKDEP */
{ "lock:lock_acquired", evsel__process_lock_acquired, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
{ "lock:lock_contended", evsel__process_lock_contended, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
{ "lock:lock_release", evsel__process_lock_release, }, /* CONFIG_LOCKDEP */
};
static const struct evsel_str_handler contention_tracepoints[] = {
{ "lock:contention_begin", evsel__process_contention_begin, },
{ "lock:contention_end", evsel__process_contention_end, },
};
static int process_event_update(struct perf_tool *tool,
union perf_event *event,
struct evlist **pevlist)
{
int ret;
ret = perf_event__process_event_update(tool, event, pevlist);
if (ret < 0)
return ret;
/* this can return -EEXIST since we call it for each evsel */
perf_session__set_tracepoints_handlers(session, lock_tracepoints);
perf_session__set_tracepoints_handlers(session, contention_tracepoints);
return 0;
}
typedef int (*tracepoint_handler)(struct evsel *evsel,
struct perf_sample *sample);
static int process_sample_event(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample,
struct evsel *evsel,
struct machine *machine)
{
int err = 0;
struct thread *thread = machine__findnew_thread(machine, sample->pid,
sample->tid);
if (thread == NULL) {
pr_debug("problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
if (evsel->handler != NULL) {
tracepoint_handler f = evsel->handler;
err = f(evsel, sample);
}
thread__put(thread);
return err;
}
static void combine_result(void)
{
unsigned int i;
struct lock_stat *st;
if (!combine_locks)
return;
for (i = 0; i < LOCKHASH_SIZE; i++) {
hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
combine_lock_stats(st);
}
}
}
static void sort_result(void)
{
unsigned int i;
struct lock_stat *st;
for (i = 0; i < LOCKHASH_SIZE; i++) {
hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
insert_to_result(st, compare);
}
}
}
static const struct {
unsigned int flags;
const char *str;
const char *name;
} lock_type_table[] = {
{ 0, "semaphore", "semaphore" },
{ LCB_F_SPIN, "spinlock", "spinlock" },
{ LCB_F_SPIN | LCB_F_READ, "rwlock:R", "rwlock" },
{ LCB_F_SPIN | LCB_F_WRITE, "rwlock:W", "rwlock" },
{ LCB_F_READ, "rwsem:R", "rwsem" },
{ LCB_F_WRITE, "rwsem:W", "rwsem" },
{ LCB_F_RT, "rt-mutex", "rt-mutex" },
{ LCB_F_RT | LCB_F_READ, "rwlock-rt:R", "rwlock-rt" },
{ LCB_F_RT | LCB_F_WRITE, "rwlock-rt:W", "rwlock-rt" },
{ LCB_F_PERCPU | LCB_F_READ, "pcpu-sem:R", "percpu-rwsem" },
{ LCB_F_PERCPU | LCB_F_WRITE, "pcpu-sem:W", "percpu-rwsem" },
{ LCB_F_MUTEX, "mutex", "mutex" },
{ LCB_F_MUTEX | LCB_F_SPIN, "mutex", "mutex" },
/* alias for get_type_flag() */
{ LCB_F_MUTEX | LCB_F_SPIN, "mutex-spin", "mutex" },
};
static const char *get_type_str(unsigned int flags)
{
flags &= LCB_F_MAX_FLAGS - 1;
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (lock_type_table[i].flags == flags)
return lock_type_table[i].str;
}
return "unknown";
}
static const char *get_type_name(unsigned int flags)
{
flags &= LCB_F_MAX_FLAGS - 1;
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (lock_type_table[i].flags == flags)
return lock_type_table[i].name;
}
return "unknown";
}
static unsigned int get_type_flag(const char *str)
{
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (!strcmp(lock_type_table[i].name, str))
return lock_type_table[i].flags;
}
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (!strcmp(lock_type_table[i].str, str))
return lock_type_table[i].flags;
}
return UINT_MAX;
}
static void lock_filter_finish(void)
{
zfree(&filters.types);
filters.nr_types = 0;
zfree(&filters.addrs);
filters.nr_addrs = 0;
for (int i = 0; i < filters.nr_syms; i++)
free(filters.syms[i]);
zfree(&filters.syms);
filters.nr_syms = 0;
}
static void sort_contention_result(void)
{
sort_result();
}
static void print_header_stdio(void)
{
struct lock_key *key;
list_for_each_entry(key, &lock_keys, list)
fprintf(lock_output, "%*s ", key->len, key->header);
switch (aggr_mode) {
case LOCK_AGGR_TASK:
fprintf(lock_output, " %10s %s\n\n", "pid",
show_lock_owner ? "owner" : "comm");
break;
case LOCK_AGGR_CALLER:
fprintf(lock_output, " %10s %s\n\n", "type", "caller");
break;
case LOCK_AGGR_ADDR:
fprintf(lock_output, " %16s %s\n\n", "address", "symbol");
break;
default:
break;
}
}
static void print_header_csv(const char *sep)
{
struct lock_key *key;
fprintf(lock_output, "# output: ");
list_for_each_entry(key, &lock_keys, list)
fprintf(lock_output, "%s%s ", key->header, sep);
switch (aggr_mode) {
case LOCK_AGGR_TASK:
fprintf(lock_output, "%s%s %s\n", "pid", sep,
show_lock_owner ? "owner" : "comm");
break;
case LOCK_AGGR_CALLER:
fprintf(lock_output, "%s%s %s", "type", sep, "caller");
if (verbose > 0)
fprintf(lock_output, "%s %s", sep, "stacktrace");
fprintf(lock_output, "\n");
break;
case LOCK_AGGR_ADDR:
fprintf(lock_output, "%s%s %s%s %s\n", "address", sep, "symbol", sep, "type");
break;
default:
break;
}
}
static void print_header(void)
{
if (!quiet) {
if (symbol_conf.field_sep)
print_header_csv(symbol_conf.field_sep);
else
print_header_stdio();
}
}
static void print_lock_stat_stdio(struct lock_contention *con, struct lock_stat *st)
{
struct lock_key *key;
struct thread *t;
int pid;
list_for_each_entry(key, &lock_keys, list) {
key->print(key, st);
fprintf(lock_output, " ");
}
switch (aggr_mode) {
case LOCK_AGGR_CALLER:
fprintf(lock_output, " %10s %s\n", get_type_str(st->flags), st->name);
break;
case LOCK_AGGR_TASK:
pid = st->addr;
t = perf_session__findnew(session, pid);
fprintf(lock_output, " %10d %s\n",
pid, pid == -1 ? "Unknown" : thread__comm_str(t));
break;
case LOCK_AGGR_ADDR:
fprintf(lock_output, " %016llx %s (%s)\n", (unsigned long long)st->addr,
st->name, get_type_name(st->flags));
break;
default:
break;
}
if (aggr_mode == LOCK_AGGR_CALLER && verbose > 0) {
struct map *kmap;
struct symbol *sym;
char buf[128];
u64 ip;
for (int i = 0; i < max_stack_depth; i++) {
if (!st->callstack || !st->callstack[i])
break;
ip = st->callstack[i];
sym = machine__find_kernel_symbol(con->machine, ip, &kmap);
get_symbol_name_offset(kmap, sym, ip, buf, sizeof(buf));
fprintf(lock_output, "\t\t\t%#lx %s\n", (unsigned long)ip, buf);
}
}
}
static void print_lock_stat_csv(struct lock_contention *con, struct lock_stat *st,
const char *sep)
{
struct lock_key *key;
struct thread *t;
int pid;
list_for_each_entry(key, &lock_keys, list) {
key->print(key, st);
fprintf(lock_output, "%s ", sep);
}
switch (aggr_mode) {
case LOCK_AGGR_CALLER:
fprintf(lock_output, "%s%s %s", get_type_str(st->flags), sep, st->name);
if (verbose <= 0)
fprintf(lock_output, "\n");
break;
case LOCK_AGGR_TASK:
pid = st->addr;
t = perf_session__findnew(session, pid);
fprintf(lock_output, "%d%s %s\n", pid, sep,
pid == -1 ? "Unknown" : thread__comm_str(t));
break;
case LOCK_AGGR_ADDR:
fprintf(lock_output, "%llx%s %s%s %s\n", (unsigned long long)st->addr, sep,
st->name, sep, get_type_name(st->flags));
break;
default:
break;
}
if (aggr_mode == LOCK_AGGR_CALLER && verbose > 0) {
struct map *kmap;
struct symbol *sym;
char buf[128];
u64 ip;
for (int i = 0; i < max_stack_depth; i++) {
if (!st->callstack || !st->callstack[i])
break;
ip = st->callstack[i];
sym = machine__find_kernel_symbol(con->machine, ip, &kmap);
get_symbol_name_offset(kmap, sym, ip, buf, sizeof(buf));
fprintf(lock_output, "%s %#lx %s", i ? ":" : sep, (unsigned long) ip, buf);
}
fprintf(lock_output, "\n");
}
}
static void print_lock_stat(struct lock_contention *con, struct lock_stat *st)
{
if (symbol_conf.field_sep)
print_lock_stat_csv(con, st, symbol_conf.field_sep);
else
print_lock_stat_stdio(con, st);
}
static void print_footer_stdio(int total, int bad, struct lock_contention_fails *fails)
{
/* Output for debug, this have to be removed */
int broken = fails->task + fails->stack + fails->time + fails->data;
if (!use_bpf)
print_bad_events(bad, total);
if (quiet || total == 0 || (broken == 0 && verbose <= 0))
return;
total += broken;
fprintf(lock_output, "\n=== output for debug ===\n\n");
fprintf(lock_output, "bad: %d, total: %d\n", broken, total);
fprintf(lock_output, "bad rate: %.2f %%\n", 100.0 * broken / total);
fprintf(lock_output, "histogram of failure reasons\n");
fprintf(lock_output, " %10s: %d\n", "task", fails->task);
fprintf(lock_output, " %10s: %d\n", "stack", fails->stack);
fprintf(lock_output, " %10s: %d\n", "time", fails->time);
fprintf(lock_output, " %10s: %d\n", "data", fails->data);
}
static void print_footer_csv(int total, int bad, struct lock_contention_fails *fails,
const char *sep)
{
/* Output for debug, this have to be removed */
if (use_bpf)
bad = fails->task + fails->stack + fails->time + fails->data;
if (quiet || total == 0 || (bad == 0 && verbose <= 0))
return;
total += bad;
fprintf(lock_output, "# debug: total=%d%s bad=%d", total, sep, bad);
if (use_bpf) {
fprintf(lock_output, "%s bad_%s=%d", sep, "task", fails->task);
fprintf(lock_output, "%s bad_%s=%d", sep, "stack", fails->stack);
fprintf(lock_output, "%s bad_%s=%d", sep, "time", fails->time);
fprintf(lock_output, "%s bad_%s=%d", sep, "data", fails->data);
} else {
int i;
const char *name[4] = { "acquire", "acquired", "contended", "release" };
for (i = 0; i < BROKEN_MAX; i++)
fprintf(lock_output, "%s bad_%s=%d", sep, name[i], bad_hist[i]);
}
fprintf(lock_output, "\n");
}
static void print_footer(int total, int bad, struct lock_contention_fails *fails)
{
if (symbol_conf.field_sep)
print_footer_csv(total, bad, fails, symbol_conf.field_sep);
else
print_footer_stdio(total, bad, fails);
}
static void print_contention_result(struct lock_contention *con)
{
struct lock_stat *st;
int bad, total, printed;
if (!quiet)
print_header();
bad = total = printed = 0;
while ((st = pop_from_result())) {
total += use_bpf ? st->nr_contended : 1;
if (st->broken)
bad++;
if (!st->wait_time_total)
continue;
print_lock_stat(con, st);
if (++printed >= print_nr_entries)
break;
}
if (print_nr_entries) {
/* update the total/bad stats */
while ((st = pop_from_result())) {
total += use_bpf ? st->nr_contended : 1;
if (st->broken)
bad++;
}
}
/* some entries are collected but hidden by the callstack filter */
total += con->nr_filtered;
print_footer(total, bad, &con->fails);
}
static bool force;
static int __cmd_report(bool display_info)
{
int err = -EINVAL;
struct perf_tool eops = {
.attr = perf_event__process_attr,
.event_update = process_event_update,
.sample = process_sample_event,
.comm = perf_event__process_comm,
.mmap = perf_event__process_mmap,
.namespaces = perf_event__process_namespaces,
.tracing_data = perf_event__process_tracing_data,
.ordered_events = true,
};
struct perf_data data = {
.path = input_name,
.mode = PERF_DATA_MODE_READ,
.force = force,
};
session = perf_session__new(&data, &eops);
if (IS_ERR(session)) {
pr_err("Initializing perf session failed\n");
return PTR_ERR(session);
}
symbol_conf.allow_aliases = true;
symbol__init(&session->header.env);
if (!data.is_pipe) {
if (!perf_session__has_traces(session, "lock record"))
goto out_delete;
if (perf_session__set_tracepoints_handlers(session, lock_tracepoints)) {
pr_err("Initializing perf session tracepoint handlers failed\n");
goto out_delete;
}
if (perf_session__set_tracepoints_handlers(session, contention_tracepoints)) {
pr_err("Initializing perf session tracepoint handlers failed\n");
goto out_delete;
}
}
if (setup_output_field(false, output_fields))
goto out_delete;
if (select_key(false))
goto out_delete;
if (show_thread_stats)
aggr_mode = LOCK_AGGR_TASK;
err = perf_session__process_events(session);
if (err)
goto out_delete;
setup_pager();
if (display_info) /* used for info subcommand */
err = dump_info();
else {
combine_result();
sort_result();
print_result();
}
out_delete:
perf_session__delete(session);
return err;
}
static void sighandler(int sig __maybe_unused)
{
}
static int check_lock_contention_options(const struct option *options,
const char * const *usage)
{
if (show_thread_stats && show_lock_addrs) {
pr_err("Cannot use thread and addr mode together\n");
parse_options_usage(usage, options, "threads", 0);
parse_options_usage(NULL, options, "lock-addr", 0);
return -1;
}
if (show_lock_owner && !use_bpf) {
pr_err("Lock owners are available only with BPF\n");
parse_options_usage(usage, options, "lock-owner", 0);
parse_options_usage(NULL, options, "use-bpf", 0);
return -1;
}
if (show_lock_owner && show_lock_addrs) {
pr_err("Cannot use owner and addr mode together\n");
parse_options_usage(usage, options, "lock-owner", 0);
parse_options_usage(NULL, options, "lock-addr", 0);
return -1;
}
if (symbol_conf.field_sep) {
if (strstr(symbol_conf.field_sep, ":") || /* part of type flags */
strstr(symbol_conf.field_sep, "+") || /* part of caller offset */
strstr(symbol_conf.field_sep, ".")) { /* can be in a symbol name */
pr_err("Cannot use the separator that is already used\n");
parse_options_usage(usage, options, "x", 1);
return -1;
}
}
if (show_lock_owner)
show_thread_stats = true;
return 0;
}
static int __cmd_contention(int argc, const char **argv)
{
int err = -EINVAL;
struct perf_tool eops = {
.attr = perf_event__process_attr,
.event_update = process_event_update,
.sample = process_sample_event,
.comm = perf_event__process_comm,
.mmap = perf_event__process_mmap,
.tracing_data = perf_event__process_tracing_data,
.ordered_events = true,
};
struct perf_data data = {
.path = input_name,
.mode = PERF_DATA_MODE_READ,
.force = force,
};
struct lock_contention con = {
.target = &target,
.map_nr_entries = bpf_map_entries,
.max_stack = max_stack_depth,
.stack_skip = stack_skip,
.filters = &filters,
.save_callstack = needs_callstack(),
.owner = show_lock_owner,
};
lockhash_table = calloc(LOCKHASH_SIZE, sizeof(*lockhash_table));
if (!lockhash_table)
return -ENOMEM;
con.result = &lockhash_table[0];
session = perf_session__new(use_bpf ? NULL : &data, &eops);
if (IS_ERR(session)) {
pr_err("Initializing perf session failed\n");
err = PTR_ERR(session);
goto out_delete;
}
con.machine = &session->machines.host;
con.aggr_mode = aggr_mode = show_thread_stats ? LOCK_AGGR_TASK :
show_lock_addrs ? LOCK_AGGR_ADDR : LOCK_AGGR_CALLER;
if (con.aggr_mode == LOCK_AGGR_CALLER)
con.save_callstack = true;
symbol_conf.allow_aliases = true;
symbol__init(&session->header.env);
if (use_bpf) {
err = target__validate(&target);
if (err) {
char errbuf[512];
target__strerror(&target, err, errbuf, 512);
pr_err("%s\n", errbuf);
goto out_delete;
}
signal(SIGINT, sighandler);
signal(SIGCHLD, sighandler);
signal(SIGTERM, sighandler);
con.evlist = evlist__new();
if (con.evlist == NULL) {
err = -ENOMEM;
goto out_delete;
}
err = evlist__create_maps(con.evlist, &target);
if (err < 0)
goto out_delete;
if (argc) {
err = evlist__prepare_workload(con.evlist, &target,
argv, false, NULL);
if (err < 0)
goto out_delete;
}
if (lock_contention_prepare(&con) < 0) {
pr_err("lock contention BPF setup failed\n");
goto out_delete;
}
} else if (!data.is_pipe) {
if (!perf_session__has_traces(session, "lock record"))
goto out_delete;
if (!evlist__find_evsel_by_str(session->evlist,
"lock:contention_begin")) {
pr_err("lock contention evsel not found\n");
goto out_delete;
}
if (perf_session__set_tracepoints_handlers(session,
contention_tracepoints)) {
pr_err("Initializing perf session tracepoint handlers failed\n");
goto out_delete;
}
}
if (setup_output_field(true, output_fields))
goto out_delete;
if (select_key(true))
goto out_delete;
if (symbol_conf.field_sep) {
int i;
struct lock_key *keys = contention_keys;
/* do not align output in CSV format */
for (i = 0; keys[i].name; i++)
keys[i].len = 0;
}
if (use_bpf) {
lock_contention_start();
if (argc)
evlist__start_workload(con.evlist);
/* wait for signal */
pause();
lock_contention_stop();
lock_contention_read(&con);
} else {
err = perf_session__process_events(session);
if (err)
goto out_delete;
}
setup_pager();
sort_contention_result();
print_contention_result(&con);
out_delete:
lock_filter_finish();
evlist__delete(con.evlist);
lock_contention_finish();
perf_session__delete(session);
zfree(&lockhash_table);
return err;
}
static int __cmd_record(int argc, const char **argv)
{
const char *record_args[] = {
"record", "-R", "-m", "1024", "-c", "1", "--synth", "task",
};
const char *callgraph_args[] = {
"--call-graph", "fp," __stringify(CONTENTION_STACK_DEPTH),
};
unsigned int rec_argc, i, j, ret;
unsigned int nr_tracepoints;
unsigned int nr_callgraph_args = 0;
const char **rec_argv;
bool has_lock_stat = true;
for (i = 0; i < ARRAY_SIZE(lock_tracepoints); i++) {
if (!is_valid_tracepoint(lock_tracepoints[i].name)) {
pr_debug("tracepoint %s is not enabled. "
"Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled?\n",
lock_tracepoints[i].name);
has_lock_stat = false;
break;
}
}
if (has_lock_stat)
goto setup_args;
for (i = 0; i < ARRAY_SIZE(contention_tracepoints); i++) {
if (!is_valid_tracepoint(contention_tracepoints[i].name)) {
pr_err("tracepoint %s is not enabled.\n",
contention_tracepoints[i].name);
return 1;
}
}
nr_callgraph_args = ARRAY_SIZE(callgraph_args);
setup_args:
rec_argc = ARRAY_SIZE(record_args) + nr_callgraph_args + argc - 1;
if (has_lock_stat)
nr_tracepoints = ARRAY_SIZE(lock_tracepoints);
else
nr_tracepoints = ARRAY_SIZE(contention_tracepoints);
/* factor of 2 is for -e in front of each tracepoint */
rec_argc += 2 * nr_tracepoints;
rec_argv = calloc(rec_argc + 1, sizeof(char *));
if (!rec_argv)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(record_args); i++)
rec_argv[i] = strdup(record_args[i]);
for (j = 0; j < nr_tracepoints; j++) {
const char *ev_name;
if (has_lock_stat)
ev_name = strdup(lock_tracepoints[j].name);
else
ev_name = strdup(contention_tracepoints[j].name);
if (!ev_name)
return -ENOMEM;
rec_argv[i++] = "-e";
rec_argv[i++] = ev_name;
}
for (j = 0; j < nr_callgraph_args; j++, i++)
rec_argv[i] = callgraph_args[j];
for (j = 1; j < (unsigned int)argc; j++, i++)
rec_argv[i] = argv[j];
BUG_ON(i != rec_argc);
ret = cmd_record(i, rec_argv);
free(rec_argv);
return ret;
}
static int parse_map_entry(const struct option *opt, const char *str,
int unset __maybe_unused)
{
unsigned long *len = (unsigned long *)opt->value;
unsigned long val;
char *endptr;
errno = 0;
val = strtoul(str, &endptr, 0);
if (*endptr != '\0' || errno != 0) {
pr_err("invalid BPF map length: %s\n", str);
return -1;
}
*len = val;
return 0;
}
static int parse_max_stack(const struct option *opt, const char *str,
int unset __maybe_unused)
{
unsigned long *len = (unsigned long *)opt->value;
long val;
char *endptr;
errno = 0;
val = strtol(str, &endptr, 0);
if (*endptr != '\0' || errno != 0) {
pr_err("invalid max stack depth: %s\n", str);
return -1;
}
if (val < 0 || val > sysctl__max_stack()) {
pr_err("invalid max stack depth: %ld\n", val);
return -1;
}
*len = val;
return 0;
}
static bool add_lock_type(unsigned int flags)
{
unsigned int *tmp;
tmp = realloc(filters.types, (filters.nr_types + 1) * sizeof(*filters.types));
if (tmp == NULL)
return false;
tmp[filters.nr_types++] = flags;
filters.types = tmp;
return true;
}
static int parse_lock_type(const struct option *opt __maybe_unused, const char *str,
int unset __maybe_unused)
{
char *s, *tmp, *tok;
int ret = 0;
s = strdup(str);
if (s == NULL)
return -1;
for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
unsigned int flags = get_type_flag(tok);
if (flags == -1U) {
pr_err("Unknown lock flags: %s\n", tok);
ret = -1;
break;
}
if (!add_lock_type(flags)) {
ret = -1;
break;
}
}
free(s);
return ret;
}
static bool add_lock_addr(unsigned long addr)
{
unsigned long *tmp;
tmp = realloc(filters.addrs, (filters.nr_addrs + 1) * sizeof(*filters.addrs));
if (tmp == NULL) {
pr_err("Memory allocation failure\n");
return false;
}
tmp[filters.nr_addrs++] = addr;
filters.addrs = tmp;
return true;
}
static bool add_lock_sym(char *name)
{
char **tmp;
char *sym = strdup(name);
if (sym == NULL) {
pr_err("Memory allocation failure\n");
return false;
}
tmp = realloc(filters.syms, (filters.nr_syms + 1) * sizeof(*filters.syms));
if (tmp == NULL) {
pr_err("Memory allocation failure\n");
free(sym);
return false;
}
tmp[filters.nr_syms++] = sym;
filters.syms = tmp;
return true;
}
static int parse_lock_addr(const struct option *opt __maybe_unused, const char *str,
int unset __maybe_unused)
{
char *s, *tmp, *tok;
int ret = 0;
u64 addr;
s = strdup(str);
if (s == NULL)
return -1;
for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
char *end;
addr = strtoul(tok, &end, 16);
if (*end == '\0') {
if (!add_lock_addr(addr)) {
ret = -1;
break;
}
continue;
}
/*
* At this moment, we don't have kernel symbols. Save the symbols
* in a separate list and resolve them to addresses later.
*/
if (!add_lock_sym(tok)) {
ret = -1;
break;
}
}
free(s);
return ret;
}
static int parse_call_stack(const struct option *opt __maybe_unused, const char *str,
int unset __maybe_unused)
{
char *s, *tmp, *tok;
int ret = 0;
s = strdup(str);
if (s == NULL)
return -1;
for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
struct callstack_filter *entry;
entry = malloc(sizeof(*entry) + strlen(tok) + 1);
if (entry == NULL) {
pr_err("Memory allocation failure\n");
return -1;
}
strcpy(entry->name, tok);
list_add_tail(&entry->list, &callstack_filters);
}
free(s);
return ret;
}
static int parse_output(const struct option *opt __maybe_unused, const char *str,
int unset __maybe_unused)
{
const char **name = (const char **)opt->value;
if (str == NULL)
return -1;
lock_output = fopen(str, "w");
if (lock_output == NULL) {
pr_err("Cannot open %s\n", str);
return -1;
}
*name = str;
return 0;
}
int cmd_lock(int argc, const char **argv)
{
const struct option lock_options[] = {
OPT_STRING('i', "input", &input_name, "file", "input file name"),
OPT_CALLBACK(0, "output", &output_name, "file", "output file name", parse_output),
OPT_INCR('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
OPT_STRING(0, "vmlinux", &symbol_conf.vmlinux_name,
"file", "vmlinux pathname"),
OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
"file", "kallsyms pathname"),
OPT_BOOLEAN('q', "quiet", &quiet, "Do not show any warnings or messages"),
OPT_END()
};
const struct option info_options[] = {
OPT_BOOLEAN('t', "threads", &info_threads,
"dump thread list in perf.data"),
OPT_BOOLEAN('m', "map", &info_map,
"map of lock instances (address:name table)"),
OPT_PARENT(lock_options)
};
const struct option report_options[] = {
OPT_STRING('k', "key", &sort_key, "acquired",
"key for sorting (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
OPT_STRING('F', "field", &output_fields, NULL,
"output fields (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
/* TODO: type */
OPT_BOOLEAN('c', "combine-locks", &combine_locks,
"combine locks in the same class"),
OPT_BOOLEAN('t', "threads", &show_thread_stats,
"show per-thread lock stats"),
OPT_INTEGER('E', "entries", &print_nr_entries, "display this many functions"),
OPT_PARENT(lock_options)
};
struct option contention_options[] = {
OPT_STRING('k', "key", &sort_key, "wait_total",
"key for sorting (contended / wait_total / wait_max / wait_min / avg_wait)"),
OPT_STRING('F', "field", &output_fields, "contended,wait_total,wait_max,avg_wait",
"output fields (contended / wait_total / wait_max / wait_min / avg_wait)"),
OPT_BOOLEAN('t', "threads", &show_thread_stats,
"show per-thread lock stats"),
OPT_BOOLEAN('b', "use-bpf", &use_bpf, "use BPF program to collect lock contention stats"),
OPT_BOOLEAN('a', "all-cpus", &target.system_wide,
"System-wide collection from all CPUs"),
OPT_STRING('C', "cpu", &target.cpu_list, "cpu",
"List of cpus to monitor"),
OPT_STRING('p', "pid", &target.pid, "pid",
"Trace on existing process id"),
OPT_STRING(0, "tid", &target.tid, "tid",
"Trace on existing thread id (exclusive to --pid)"),
OPT_CALLBACK('M', "map-nr-entries", &bpf_map_entries, "num",
"Max number of BPF map entries", parse_map_entry),
OPT_CALLBACK(0, "max-stack", &max_stack_depth, "num",
"Set the maximum stack depth when collecting lopck contention, "
"Default: " __stringify(CONTENTION_STACK_DEPTH), parse_max_stack),
OPT_INTEGER(0, "stack-skip", &stack_skip,
"Set the number of stack depth to skip when finding a lock caller, "
"Default: " __stringify(CONTENTION_STACK_SKIP)),
OPT_INTEGER('E', "entries", &print_nr_entries, "display this many functions"),
OPT_BOOLEAN('l', "lock-addr", &show_lock_addrs, "show lock stats by address"),
OPT_CALLBACK('Y', "type-filter", NULL, "FLAGS",
"Filter specific type of locks", parse_lock_type),
OPT_CALLBACK('L', "lock-filter", NULL, "ADDRS/NAMES",
"Filter specific address/symbol of locks", parse_lock_addr),
OPT_CALLBACK('S', "callstack-filter", NULL, "NAMES",
"Filter specific function in the callstack", parse_call_stack),
OPT_BOOLEAN('o', "lock-owner", &show_lock_owner, "show lock owners instead of waiters"),
OPT_STRING_NOEMPTY('x', "field-separator", &symbol_conf.field_sep, "separator",
"print result in CSV format with custom separator"),
OPT_PARENT(lock_options)
};
const char * const info_usage[] = {
"perf lock info [<options>]",
NULL
};
const char *const lock_subcommands[] = { "record", "report", "script",
"info", "contention", NULL };
const char *lock_usage[] = {
NULL,
NULL
};
const char * const report_usage[] = {
"perf lock report [<options>]",
NULL
};
const char * const contention_usage[] = {
"perf lock contention [<options>]",
NULL
};
unsigned int i;
int rc = 0;
lockhash_table = calloc(LOCKHASH_SIZE, sizeof(*lockhash_table));
if (!lockhash_table)
return -ENOMEM;
for (i = 0; i < LOCKHASH_SIZE; i++)
INIT_HLIST_HEAD(lockhash_table + i);
lock_output = stderr;
argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc)
usage_with_options(lock_usage, lock_options);
if (strlen(argv[0]) > 2 && strstarts("record", argv[0])) {
return __cmd_record(argc, argv);
} else if (strlen(argv[0]) > 2 && strstarts("report", argv[0])) {
trace_handler = &report_lock_ops;
if (argc) {
argc = parse_options(argc, argv,
report_options, report_usage, 0);
if (argc)
usage_with_options(report_usage, report_options);
}
rc = __cmd_report(false);
} else if (!strcmp(argv[0], "script")) {
/* Aliased to 'perf script' */
rc = cmd_script(argc, argv);
} else if (!strcmp(argv[0], "info")) {
if (argc) {
argc = parse_options(argc, argv,
info_options, info_usage, 0);
if (argc)
usage_with_options(info_usage, info_options);
}
/* recycling report_lock_ops */
trace_handler = &report_lock_ops;
rc = __cmd_report(true);
} else if (strlen(argv[0]) > 2 && strstarts("contention", argv[0])) {
trace_handler = &contention_lock_ops;
sort_key = "wait_total";
output_fields = "contended,wait_total,wait_max,avg_wait";
#ifndef HAVE_BPF_SKEL
set_option_nobuild(contention_options, 'b', "use-bpf",
"no BUILD_BPF_SKEL=1", false);
#endif
if (argc) {
argc = parse_options(argc, argv, contention_options,
contention_usage, 0);
}
if (check_lock_contention_options(contention_options,
contention_usage) < 0)
return -1;
rc = __cmd_contention(argc, argv);
} else {
usage_with_options(lock_usage, lock_options);
}
zfree(&lockhash_table);
return rc;
}