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linux/tools/perf/util/machine.c
Ian Rogers 2832ef81d4 perf map: Add reference count checking 
There's no strict get/put policy with map that leads to leaks or use
after free. Reference count checking identifies correct pairing of gets
and puts.

Committer notes:

Extracted from a larger patch removing bits that were covered by the use
of pre-existing map__ accessors (e.g. maps__nr_maps()) and new ones
added (map__refcnt() and the maps__set_ ones) to reduce
RC_CHK_ACCESS(maps)-> source code pollution.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Link: https://lore.kernel.org/lkml/20230407230405.2931830-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 12:57:53 -03:00

3436 lines
84 KiB
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// SPDX-License-Identifier: GPL-2.0
#include <dirent.h>
#include <errno.h>
#include <inttypes.h>
#include <regex.h>
#include <stdlib.h>
#include "callchain.h"
#include "debug.h"
#include "dso.h"
#include "env.h"
#include "event.h"
#include "evsel.h"
#include "hist.h"
#include "machine.h"
#include "map.h"
#include "map_symbol.h"
#include "branch.h"
#include "mem-events.h"
#include "path.h"
#include "srcline.h"
#include "symbol.h"
#include "sort.h"
#include "strlist.h"
#include "target.h"
#include "thread.h"
#include "util.h"
#include "vdso.h"
#include <stdbool.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "unwind.h"
#include "linux/hash.h"
#include "asm/bug.h"
#include "bpf-event.h"
#include <internal/lib.h> // page_size
#include "cgroup.h"
#include "arm64-frame-pointer-unwind-support.h"
#include <linux/ctype.h>
#include <symbol/kallsyms.h>
#include <linux/mman.h>
#include <linux/string.h>
#include <linux/zalloc.h>
static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock);
static int append_inlines(struct callchain_cursor *cursor, struct map_symbol *ms, u64 ip);
static struct dso *machine__kernel_dso(struct machine *machine)
{
return map__dso(machine->vmlinux_map);
}
static void dsos__init(struct dsos *dsos)
{
INIT_LIST_HEAD(&dsos->head);
dsos->root = RB_ROOT;
init_rwsem(&dsos->lock);
}
static void machine__threads_init(struct machine *machine)
{
int i;
for (i = 0; i < THREADS__TABLE_SIZE; i++) {
struct threads *threads = &machine->threads[i];
threads->entries = RB_ROOT_CACHED;
init_rwsem(&threads->lock);
threads->nr = 0;
INIT_LIST_HEAD(&threads->dead);
threads->last_match = NULL;
}
}
static int machine__set_mmap_name(struct machine *machine)
{
if (machine__is_host(machine))
machine->mmap_name = strdup("[kernel.kallsyms]");
else if (machine__is_default_guest(machine))
machine->mmap_name = strdup("[guest.kernel.kallsyms]");
else if (asprintf(&machine->mmap_name, "[guest.kernel.kallsyms.%d]",
machine->pid) < 0)
machine->mmap_name = NULL;
return machine->mmap_name ? 0 : -ENOMEM;
}
static void thread__set_guest_comm(struct thread *thread, pid_t pid)
{
char comm[64];
snprintf(comm, sizeof(comm), "[guest/%d]", pid);
thread__set_comm(thread, comm, 0);
}
int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
{
int err = -ENOMEM;
memset(machine, 0, sizeof(*machine));
machine->kmaps = maps__new(machine);
if (machine->kmaps == NULL)
return -ENOMEM;
RB_CLEAR_NODE(&machine->rb_node);
dsos__init(&machine->dsos);
machine__threads_init(machine);
machine->vdso_info = NULL;
machine->env = NULL;
machine->pid = pid;
machine->id_hdr_size = 0;
machine->kptr_restrict_warned = false;
machine->comm_exec = false;
machine->kernel_start = 0;
machine->vmlinux_map = NULL;
machine->root_dir = strdup(root_dir);
if (machine->root_dir == NULL)
goto out;
if (machine__set_mmap_name(machine))
goto out;
if (pid != HOST_KERNEL_ID) {
struct thread *thread = machine__findnew_thread(machine, -1,
pid);
if (thread == NULL)
goto out;
thread__set_guest_comm(thread, pid);
thread__put(thread);
}
machine->current_tid = NULL;
err = 0;
out:
if (err) {
zfree(&machine->kmaps);
zfree(&machine->root_dir);
zfree(&machine->mmap_name);
}
return 0;
}
struct machine *machine__new_host(void)
{
struct machine *machine = malloc(sizeof(*machine));
if (machine != NULL) {
machine__init(machine, "", HOST_KERNEL_ID);
if (machine__create_kernel_maps(machine) < 0)
goto out_delete;
}
return machine;
out_delete:
free(machine);
return NULL;
}
struct machine *machine__new_kallsyms(void)
{
struct machine *machine = machine__new_host();
/*
* FIXME:
* 1) We should switch to machine__load_kallsyms(), i.e. not explicitly
* ask for not using the kcore parsing code, once this one is fixed
* to create a map per module.
*/
if (machine && machine__load_kallsyms(machine, "/proc/kallsyms") <= 0) {
machine__delete(machine);
machine = NULL;
}
return machine;
}
static void dsos__purge(struct dsos *dsos)
{
struct dso *pos, *n;
down_write(&dsos->lock);
list_for_each_entry_safe(pos, n, &dsos->head, node) {
RB_CLEAR_NODE(&pos->rb_node);
pos->root = NULL;
list_del_init(&pos->node);
dso__put(pos);
}
up_write(&dsos->lock);
}
static void dsos__exit(struct dsos *dsos)
{
dsos__purge(dsos);
exit_rwsem(&dsos->lock);
}
void machine__delete_threads(struct machine *machine)
{
struct rb_node *nd;
int i;
for (i = 0; i < THREADS__TABLE_SIZE; i++) {
struct threads *threads = &machine->threads[i];
down_write(&threads->lock);
nd = rb_first_cached(&threads->entries);
while (nd) {
struct thread *t = rb_entry(nd, struct thread, rb_node);
nd = rb_next(nd);
__machine__remove_thread(machine, t, false);
}
up_write(&threads->lock);
}
}
void machine__exit(struct machine *machine)
{
int i;
if (machine == NULL)
return;
machine__destroy_kernel_maps(machine);
maps__delete(machine->kmaps);
dsos__exit(&machine->dsos);
machine__exit_vdso(machine);
zfree(&machine->root_dir);
zfree(&machine->mmap_name);
zfree(&machine->current_tid);
zfree(&machine->kallsyms_filename);
for (i = 0; i < THREADS__TABLE_SIZE; i++) {
struct threads *threads = &machine->threads[i];
struct thread *thread, *n;
/*
* Forget about the dead, at this point whatever threads were
* left in the dead lists better have a reference count taken
* by who is using them, and then, when they drop those references
* and it finally hits zero, thread__put() will check and see that
* its not in the dead threads list and will not try to remove it
* from there, just calling thread__delete() straight away.
*/
list_for_each_entry_safe(thread, n, &threads->dead, node)
list_del_init(&thread->node);
exit_rwsem(&threads->lock);
}
}
void machine__delete(struct machine *machine)
{
if (machine) {
machine__exit(machine);
free(machine);
}
}
void machines__init(struct machines *machines)
{
machine__init(&machines->host, "", HOST_KERNEL_ID);
machines->guests = RB_ROOT_CACHED;
}
void machines__exit(struct machines *machines)
{
machine__exit(&machines->host);
/* XXX exit guest */
}
struct machine *machines__add(struct machines *machines, pid_t pid,
const char *root_dir)
{
struct rb_node **p = &machines->guests.rb_root.rb_node;
struct rb_node *parent = NULL;
struct machine *pos, *machine = malloc(sizeof(*machine));
bool leftmost = true;
if (machine == NULL)
return NULL;
if (machine__init(machine, root_dir, pid) != 0) {
free(machine);
return NULL;
}
while (*p != NULL) {
parent = *p;
pos = rb_entry(parent, struct machine, rb_node);
if (pid < pos->pid)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
rb_link_node(&machine->rb_node, parent, p);
rb_insert_color_cached(&machine->rb_node, &machines->guests, leftmost);
machine->machines = machines;
return machine;
}
void machines__set_comm_exec(struct machines *machines, bool comm_exec)
{
struct rb_node *nd;
machines->host.comm_exec = comm_exec;
for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
struct machine *machine = rb_entry(nd, struct machine, rb_node);
machine->comm_exec = comm_exec;
}
}
struct machine *machines__find(struct machines *machines, pid_t pid)
{
struct rb_node **p = &machines->guests.rb_root.rb_node;
struct rb_node *parent = NULL;
struct machine *machine;
struct machine *default_machine = NULL;
if (pid == HOST_KERNEL_ID)
return &machines->host;
while (*p != NULL) {
parent = *p;
machine = rb_entry(parent, struct machine, rb_node);
if (pid < machine->pid)
p = &(*p)->rb_left;
else if (pid > machine->pid)
p = &(*p)->rb_right;
else
return machine;
if (!machine->pid)
default_machine = machine;
}
return default_machine;
}
struct machine *machines__findnew(struct machines *machines, pid_t pid)
{
char path[PATH_MAX];
const char *root_dir = "";
struct machine *machine = machines__find(machines, pid);
if (machine && (machine->pid == pid))
goto out;
if ((pid != HOST_KERNEL_ID) &&
(pid != DEFAULT_GUEST_KERNEL_ID) &&
(symbol_conf.guestmount)) {
sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
if (access(path, R_OK)) {
static struct strlist *seen;
if (!seen)
seen = strlist__new(NULL, NULL);
if (!strlist__has_entry(seen, path)) {
pr_err("Can't access file %s\n", path);
strlist__add(seen, path);
}
machine = NULL;
goto out;
}
root_dir = path;
}
machine = machines__add(machines, pid, root_dir);
out:
return machine;
}
struct machine *machines__find_guest(struct machines *machines, pid_t pid)
{
struct machine *machine = machines__find(machines, pid);
if (!machine)
machine = machines__findnew(machines, DEFAULT_GUEST_KERNEL_ID);
return machine;
}
/*
* A common case for KVM test programs is that the test program acts as the
* hypervisor, creating, running and destroying the virtual machine, and
* providing the guest object code from its own object code. In this case,
* the VM is not running an OS, but only the functions loaded into it by the
* hypervisor test program, and conveniently, loaded at the same virtual
* addresses.
*
* Normally to resolve addresses, MMAP events are needed to map addresses
* back to the object code and debug symbols for that object code.
*
* Currently, there is no way to get such mapping information from guests
* but, in the scenario described above, the guest has the same mappings
* as the hypervisor, so support for that scenario can be achieved.
*
* To support that, copy the host thread's maps to the guest thread's maps.
* Note, we do not discover the guest until we encounter a guest event,
* which works well because it is not until then that we know that the host
* thread's maps have been set up.
*
* This function returns the guest thread. Apart from keeping the data
* structures sane, using a thread belonging to the guest machine, instead
* of the host thread, allows it to have its own comm (refer
* thread__set_guest_comm()).
*/
static struct thread *findnew_guest_code(struct machine *machine,
struct machine *host_machine,
pid_t pid)
{
struct thread *host_thread;
struct thread *thread;
int err;
if (!machine)
return NULL;
thread = machine__findnew_thread(machine, -1, pid);
if (!thread)
return NULL;
/* Assume maps are set up if there are any */
if (maps__nr_maps(thread->maps))
return thread;
host_thread = machine__find_thread(host_machine, -1, pid);
if (!host_thread)
goto out_err;
thread__set_guest_comm(thread, pid);
/*
* Guest code can be found in hypervisor process at the same address
* so copy host maps.
*/
err = maps__clone(thread, host_thread->maps);
thread__put(host_thread);
if (err)
goto out_err;
return thread;
out_err:
thread__zput(thread);
return NULL;
}
struct thread *machines__findnew_guest_code(struct machines *machines, pid_t pid)
{
struct machine *host_machine = machines__find(machines, HOST_KERNEL_ID);
struct machine *machine = machines__findnew(machines, pid);
return findnew_guest_code(machine, host_machine, pid);
}
struct thread *machine__findnew_guest_code(struct machine *machine, pid_t pid)
{
struct machines *machines = machine->machines;
struct machine *host_machine;
if (!machines)
return NULL;
host_machine = machines__find(machines, HOST_KERNEL_ID);
return findnew_guest_code(machine, host_machine, pid);
}
void machines__process_guests(struct machines *machines,
machine__process_t process, void *data)
{
struct rb_node *nd;
for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
process(pos, data);
}
}
void machines__set_id_hdr_size(struct machines *machines, u16 id_hdr_size)
{
struct rb_node *node;
struct machine *machine;
machines->host.id_hdr_size = id_hdr_size;
for (node = rb_first_cached(&machines->guests); node;
node = rb_next(node)) {
machine = rb_entry(node, struct machine, rb_node);
machine->id_hdr_size = id_hdr_size;
}
return;
}
static void machine__update_thread_pid(struct machine *machine,
struct thread *th, pid_t pid)
{
struct thread *leader;
if (pid == th->pid_ || pid == -1 || th->pid_ != -1)
return;
th->pid_ = pid;
if (th->pid_ == th->tid)
return;
leader = __machine__findnew_thread(machine, th->pid_, th->pid_);
if (!leader)
goto out_err;
if (!leader->maps)
leader->maps = maps__new(machine);
if (!leader->maps)
goto out_err;
if (th->maps == leader->maps)
return;
if (th->maps) {
/*
* Maps are created from MMAP events which provide the pid and
* tid. Consequently there never should be any maps on a thread
* with an unknown pid. Just print an error if there are.
*/
if (!maps__empty(th->maps))
pr_err("Discarding thread maps for %d:%d\n",
th->pid_, th->tid);
maps__put(th->maps);
}
th->maps = maps__get(leader->maps);
out_put:
thread__put(leader);
return;
out_err:
pr_err("Failed to join map groups for %d:%d\n", th->pid_, th->tid);
goto out_put;
}
/*
* Front-end cache - TID lookups come in blocks,
* so most of the time we dont have to look up
* the full rbtree:
*/
static struct thread*
__threads__get_last_match(struct threads *threads, struct machine *machine,
int pid, int tid)
{
struct thread *th;
th = threads->last_match;
if (th != NULL) {
if (th->tid == tid) {
machine__update_thread_pid(machine, th, pid);
return thread__get(th);
}
threads->last_match = NULL;
}
return NULL;
}
static struct thread*
threads__get_last_match(struct threads *threads, struct machine *machine,
int pid, int tid)
{
struct thread *th = NULL;
if (perf_singlethreaded)
th = __threads__get_last_match(threads, machine, pid, tid);
return th;
}
static void
__threads__set_last_match(struct threads *threads, struct thread *th)
{
threads->last_match = th;
}
static void
threads__set_last_match(struct threads *threads, struct thread *th)
{
if (perf_singlethreaded)
__threads__set_last_match(threads, th);
}
/*
* Caller must eventually drop thread->refcnt returned with a successful
* lookup/new thread inserted.
*/
static struct thread *____machine__findnew_thread(struct machine *machine,
struct threads *threads,
pid_t pid, pid_t tid,
bool create)
{
struct rb_node **p = &threads->entries.rb_root.rb_node;
struct rb_node *parent = NULL;
struct thread *th;
bool leftmost = true;
th = threads__get_last_match(threads, machine, pid, tid);
if (th)
return th;
while (*p != NULL) {
parent = *p;
th = rb_entry(parent, struct thread, rb_node);
if (th->tid == tid) {
threads__set_last_match(threads, th);
machine__update_thread_pid(machine, th, pid);
return thread__get(th);
}
if (tid < th->tid)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
if (!create)
return NULL;
th = thread__new(pid, tid);
if (th != NULL) {
rb_link_node(&th->rb_node, parent, p);
rb_insert_color_cached(&th->rb_node, &threads->entries, leftmost);
/*
* We have to initialize maps separately after rb tree is updated.
*
* The reason is that we call machine__findnew_thread
* within thread__init_maps to find the thread
* leader and that would screwed the rb tree.
*/
if (thread__init_maps(th, machine)) {
rb_erase_cached(&th->rb_node, &threads->entries);
RB_CLEAR_NODE(&th->rb_node);
thread__put(th);
return NULL;
}
/*
* It is now in the rbtree, get a ref
*/
thread__get(th);
threads__set_last_match(threads, th);
++threads->nr;
}
return th;
}
struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid)
{
return ____machine__findnew_thread(machine, machine__threads(machine, tid), pid, tid, true);
}
struct thread *machine__findnew_thread(struct machine *machine, pid_t pid,
pid_t tid)
{
struct threads *threads = machine__threads(machine, tid);
struct thread *th;
down_write(&threads->lock);
th = __machine__findnew_thread(machine, pid, tid);
up_write(&threads->lock);
return th;
}
struct thread *machine__find_thread(struct machine *machine, pid_t pid,
pid_t tid)
{
struct threads *threads = machine__threads(machine, tid);
struct thread *th;
down_read(&threads->lock);
th = ____machine__findnew_thread(machine, threads, pid, tid, false);
up_read(&threads->lock);
return th;
}
/*
* Threads are identified by pid and tid, and the idle task has pid == tid == 0.
* So here a single thread is created for that, but actually there is a separate
* idle task per cpu, so there should be one 'struct thread' per cpu, but there
* is only 1. That causes problems for some tools, requiring workarounds. For
* example get_idle_thread() in builtin-sched.c, or thread_stack__per_cpu().
*/
struct thread *machine__idle_thread(struct machine *machine)
{
struct thread *thread = machine__findnew_thread(machine, 0, 0);
if (!thread || thread__set_comm(thread, "swapper", 0) ||
thread__set_namespaces(thread, 0, NULL))
pr_err("problem inserting idle task for machine pid %d\n", machine->pid);
return thread;
}
struct comm *machine__thread_exec_comm(struct machine *machine,
struct thread *thread)
{
if (machine->comm_exec)
return thread__exec_comm(thread);
else
return thread__comm(thread);
}
int machine__process_comm_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample)
{
struct thread *thread = machine__findnew_thread(machine,
event->comm.pid,
event->comm.tid);
bool exec = event->header.misc & PERF_RECORD_MISC_COMM_EXEC;
int err = 0;
if (exec)
machine->comm_exec = true;
if (dump_trace)
perf_event__fprintf_comm(event, stdout);
if (thread == NULL ||
__thread__set_comm(thread, event->comm.comm, sample->time, exec)) {
dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
err = -1;
}
thread__put(thread);
return err;
}
int machine__process_namespaces_event(struct machine *machine __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct thread *thread = machine__findnew_thread(machine,
event->namespaces.pid,
event->namespaces.tid);
int err = 0;
WARN_ONCE(event->namespaces.nr_namespaces > NR_NAMESPACES,
"\nWARNING: kernel seems to support more namespaces than perf"
" tool.\nTry updating the perf tool..\n\n");
WARN_ONCE(event->namespaces.nr_namespaces < NR_NAMESPACES,
"\nWARNING: perf tool seems to support more namespaces than"
" the kernel.\nTry updating the kernel..\n\n");
if (dump_trace)
perf_event__fprintf_namespaces(event, stdout);
if (thread == NULL ||
thread__set_namespaces(thread, sample->time, &event->namespaces)) {
dump_printf("problem processing PERF_RECORD_NAMESPACES, skipping event.\n");
err = -1;
}
thread__put(thread);
return err;
}
int machine__process_cgroup_event(struct machine *machine,
union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct cgroup *cgrp;
if (dump_trace)
perf_event__fprintf_cgroup(event, stdout);
cgrp = cgroup__findnew(machine->env, event->cgroup.id, event->cgroup.path);
if (cgrp == NULL)
return -ENOMEM;
return 0;
}
int machine__process_lost_event(struct machine *machine __maybe_unused,
union perf_event *event, struct perf_sample *sample __maybe_unused)
{
dump_printf(": id:%" PRI_lu64 ": lost:%" PRI_lu64 "\n",
event->lost.id, event->lost.lost);
return 0;
}
int machine__process_lost_samples_event(struct machine *machine __maybe_unused,
union perf_event *event, struct perf_sample *sample)
{
dump_printf(": id:%" PRIu64 ": lost samples :%" PRI_lu64 "\n",
sample->id, event->lost_samples.lost);
return 0;
}
static struct dso *machine__findnew_module_dso(struct machine *machine,
struct kmod_path *m,
const char *filename)
{
struct dso *dso;
down_write(&machine->dsos.lock);
dso = __dsos__find(&machine->dsos, m->name, true);
if (!dso) {
dso = __dsos__addnew(&machine->dsos, m->name);
if (dso == NULL)
goto out_unlock;
dso__set_module_info(dso, m, machine);
dso__set_long_name(dso, strdup(filename), true);
dso->kernel = DSO_SPACE__KERNEL;
}
dso__get(dso);
out_unlock:
up_write(&machine->dsos.lock);
return dso;
}
int machine__process_aux_event(struct machine *machine __maybe_unused,
union perf_event *event)
{
if (dump_trace)
perf_event__fprintf_aux(event, stdout);
return 0;
}
int machine__process_itrace_start_event(struct machine *machine __maybe_unused,
union perf_event *event)
{
if (dump_trace)
perf_event__fprintf_itrace_start(event, stdout);
return 0;
}
int machine__process_aux_output_hw_id_event(struct machine *machine __maybe_unused,
union perf_event *event)
{
if (dump_trace)
perf_event__fprintf_aux_output_hw_id(event, stdout);
return 0;
}
int machine__process_switch_event(struct machine *machine __maybe_unused,
union perf_event *event)
{
if (dump_trace)
perf_event__fprintf_switch(event, stdout);
return 0;
}
static int machine__process_ksymbol_register(struct machine *machine,
union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct symbol *sym;
struct dso *dso;
struct map *map = maps__find(machine__kernel_maps(machine), event->ksymbol.addr);
bool put_map = false;
int err = 0;
if (!map) {
dso = dso__new(event->ksymbol.name);
if (!dso) {
err = -ENOMEM;
goto out;
}
dso->kernel = DSO_SPACE__KERNEL;
map = map__new2(0, dso);
dso__put(dso);
if (!map) {
err = -ENOMEM;
goto out;
}
/*
* The inserted map has a get on it, we need to put to release
* the reference count here, but do it after all accesses are
* done.
*/
put_map = true;
if (event->ksymbol.ksym_type == PERF_RECORD_KSYMBOL_TYPE_OOL) {
dso->binary_type = DSO_BINARY_TYPE__OOL;
dso->data.file_size = event->ksymbol.len;
dso__set_loaded(dso);
}
map__set_start(map, event->ksymbol.addr);
map__set_end(map, map__start(map) + event->ksymbol.len);
err = maps__insert(machine__kernel_maps(machine), map);
if (err) {
err = -ENOMEM;
goto out;
}
dso__set_loaded(dso);
if (is_bpf_image(event->ksymbol.name)) {
dso->binary_type = DSO_BINARY_TYPE__BPF_IMAGE;
dso__set_long_name(dso, "", false);
}
} else {
dso = map__dso(map);
}
sym = symbol__new(map__map_ip(map, map__start(map)),
event->ksymbol.len,
0, 0, event->ksymbol.name);
if (!sym) {
err = -ENOMEM;
goto out;
}
dso__insert_symbol(dso, sym);
out:
if (put_map)
map__put(map);
return err;
}
static int machine__process_ksymbol_unregister(struct machine *machine,
union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct symbol *sym;
struct map *map;
map = maps__find(machine__kernel_maps(machine), event->ksymbol.addr);
if (!map)
return 0;
if (RC_CHK_ACCESS(map) != RC_CHK_ACCESS(machine->vmlinux_map))
maps__remove(machine__kernel_maps(machine), map);
else {
struct dso *dso = map__dso(map);
sym = dso__find_symbol(dso, map__map_ip(map, map__start(map)));
if (sym)
dso__delete_symbol(dso, sym);
}
return 0;
}
int machine__process_ksymbol(struct machine *machine __maybe_unused,
union perf_event *event,
struct perf_sample *sample)
{
if (dump_trace)
perf_event__fprintf_ksymbol(event, stdout);
if (event->ksymbol.flags & PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER)
return machine__process_ksymbol_unregister(machine, event,
sample);
return machine__process_ksymbol_register(machine, event, sample);
}
int machine__process_text_poke(struct machine *machine, union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct map *map = maps__find(machine__kernel_maps(machine), event->text_poke.addr);
u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
struct dso *dso = map ? map__dso(map) : NULL;
if (dump_trace)
perf_event__fprintf_text_poke(event, machine, stdout);
if (!event->text_poke.new_len)
return 0;
if (cpumode != PERF_RECORD_MISC_KERNEL) {
pr_debug("%s: unsupported cpumode - ignoring\n", __func__);
return 0;
}
if (dso) {
u8 *new_bytes = event->text_poke.bytes + event->text_poke.old_len;
int ret;
/*
* Kernel maps might be changed when loading symbols so loading
* must be done prior to using kernel maps.
*/
map__load(map);
ret = dso__data_write_cache_addr(dso, map, machine,
event->text_poke.addr,
new_bytes,
event->text_poke.new_len);
if (ret != event->text_poke.new_len)
pr_debug("Failed to write kernel text poke at %#" PRI_lx64 "\n",
event->text_poke.addr);
} else {
pr_debug("Failed to find kernel text poke address map for %#" PRI_lx64 "\n",
event->text_poke.addr);
}
return 0;
}
static struct map *machine__addnew_module_map(struct machine *machine, u64 start,
const char *filename)
{
struct map *map = NULL;
struct kmod_path m;
struct dso *dso;
int err;
if (kmod_path__parse_name(&m, filename))
return NULL;
dso = machine__findnew_module_dso(machine, &m, filename);
if (dso == NULL)
goto out;
map = map__new2(start, dso);
if (map == NULL)
goto out;
err = maps__insert(machine__kernel_maps(machine), map);
/* If maps__insert failed, return NULL. */
if (err) {
map__put(map);
map = NULL;
}
out:
/* put the dso here, corresponding to machine__findnew_module_dso */
dso__put(dso);
zfree(&m.name);
return map;
}
size_t machines__fprintf_dsos(struct machines *machines, FILE *fp)
{
struct rb_node *nd;
size_t ret = __dsos__fprintf(&machines->host.dsos.head, fp);
for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret += __dsos__fprintf(&pos->dsos.head, fp);
}
return ret;
}
size_t machine__fprintf_dsos_buildid(struct machine *m, FILE *fp,
bool (skip)(struct dso *dso, int parm), int parm)
{
return __dsos__fprintf_buildid(&m->dsos.head, fp, skip, parm);
}
size_t machines__fprintf_dsos_buildid(struct machines *machines, FILE *fp,
bool (skip)(struct dso *dso, int parm), int parm)
{
struct rb_node *nd;
size_t ret = machine__fprintf_dsos_buildid(&machines->host, fp, skip, parm);
for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret += machine__fprintf_dsos_buildid(pos, fp, skip, parm);
}
return ret;
}
size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp)
{
int i;
size_t printed = 0;
struct dso *kdso = machine__kernel_dso(machine);
if (kdso->has_build_id) {
char filename[PATH_MAX];
if (dso__build_id_filename(kdso, filename, sizeof(filename),
false))
printed += fprintf(fp, "[0] %s\n", filename);
}
for (i = 0; i < vmlinux_path__nr_entries; ++i)
printed += fprintf(fp, "[%d] %s\n",
i + kdso->has_build_id, vmlinux_path[i]);
return printed;
}
size_t machine__fprintf(struct machine *machine, FILE *fp)
{
struct rb_node *nd;
size_t ret;
int i;
for (i = 0; i < THREADS__TABLE_SIZE; i++) {
struct threads *threads = &machine->threads[i];
down_read(&threads->lock);
ret = fprintf(fp, "Threads: %u\n", threads->nr);
for (nd = rb_first_cached(&threads->entries); nd;
nd = rb_next(nd)) {
struct thread *pos = rb_entry(nd, struct thread, rb_node);
ret += thread__fprintf(pos, fp);
}
up_read(&threads->lock);
}
return ret;
}
static struct dso *machine__get_kernel(struct machine *machine)
{
const char *vmlinux_name = machine->mmap_name;
struct dso *kernel;
if (machine__is_host(machine)) {
if (symbol_conf.vmlinux_name)
vmlinux_name = symbol_conf.vmlinux_name;
kernel = machine__findnew_kernel(machine, vmlinux_name,
"[kernel]", DSO_SPACE__KERNEL);
} else {
if (symbol_conf.default_guest_vmlinux_name)
vmlinux_name = symbol_conf.default_guest_vmlinux_name;
kernel = machine__findnew_kernel(machine, vmlinux_name,
"[guest.kernel]",
DSO_SPACE__KERNEL_GUEST);
}
if (kernel != NULL && (!kernel->has_build_id))
dso__read_running_kernel_build_id(kernel, machine);
return kernel;
}
void machine__get_kallsyms_filename(struct machine *machine, char *buf,
size_t bufsz)
{
if (machine__is_default_guest(machine))
scnprintf(buf, bufsz, "%s", symbol_conf.default_guest_kallsyms);
else
scnprintf(buf, bufsz, "%s/proc/kallsyms", machine->root_dir);
}
const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL};
/* Figure out the start address of kernel map from /proc/kallsyms.
* Returns the name of the start symbol in *symbol_name. Pass in NULL as
* symbol_name if it's not that important.
*/
static int machine__get_running_kernel_start(struct machine *machine,
const char **symbol_name,
u64 *start, u64 *end)
{
char filename[PATH_MAX];
int i, err = -1;
const char *name;
u64 addr = 0;
machine__get_kallsyms_filename(machine, filename, PATH_MAX);
if (symbol__restricted_filename(filename, "/proc/kallsyms"))
return 0;
for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
err = kallsyms__get_function_start(filename, name, &addr);
if (!err)
break;
}
if (err)
return -1;
if (symbol_name)
*symbol_name = name;
*start = addr;
err = kallsyms__get_function_start(filename, "_etext", &addr);
if (!err)
*end = addr;
return 0;
}
int machine__create_extra_kernel_map(struct machine *machine,
struct dso *kernel,
struct extra_kernel_map *xm)
{
struct kmap *kmap;
struct map *map;
int err;
map = map__new2(xm->start, kernel);
if (!map)
return -ENOMEM;
map__set_end(map, xm->end);
map__set_pgoff(map, xm->pgoff);
kmap = map__kmap(map);
strlcpy(kmap->name, xm->name, KMAP_NAME_LEN);
err = maps__insert(machine__kernel_maps(machine), map);
if (!err) {
pr_debug2("Added extra kernel map %s %" PRIx64 "-%" PRIx64 "\n",
kmap->name, map__start(map), map__end(map));
}
map__put(map);
return err;
}
static u64 find_entry_trampoline(struct dso *dso)
{
/* Duplicates are removed so lookup all aliases */
const char *syms[] = {
"_entry_trampoline",
"__entry_trampoline_start",
"entry_SYSCALL_64_trampoline",
};
struct symbol *sym = dso__first_symbol(dso);
unsigned int i;
for (; sym; sym = dso__next_symbol(sym)) {
if (sym->binding != STB_GLOBAL)
continue;
for (i = 0; i < ARRAY_SIZE(syms); i++) {
if (!strcmp(sym->name, syms[i]))
return sym->start;
}
}
return 0;
}
/*
* These values can be used for kernels that do not have symbols for the entry
* trampolines in kallsyms.
*/
#define X86_64_CPU_ENTRY_AREA_PER_CPU 0xfffffe0000000000ULL
#define X86_64_CPU_ENTRY_AREA_SIZE 0x2c000
#define X86_64_ENTRY_TRAMPOLINE 0x6000
/* Map x86_64 PTI entry trampolines */
int machine__map_x86_64_entry_trampolines(struct machine *machine,
struct dso *kernel)
{
struct maps *kmaps = machine__kernel_maps(machine);
int nr_cpus_avail, cpu;
bool found = false;
struct map_rb_node *rb_node;
u64 pgoff;
/*
* In the vmlinux case, pgoff is a virtual address which must now be
* mapped to a vmlinux offset.
*/
maps__for_each_entry(kmaps, rb_node) {
struct map *dest_map, *map = rb_node->map;
struct kmap *kmap = __map__kmap(map);
if (!kmap || !is_entry_trampoline(kmap->name))
continue;
dest_map = maps__find(kmaps, map__pgoff(map));
if (dest_map != map)
map__set_pgoff(map, map__map_ip(dest_map, map__pgoff(map)));
found = true;
}
if (found || machine->trampolines_mapped)
return 0;
pgoff = find_entry_trampoline(kernel);
if (!pgoff)
return 0;
nr_cpus_avail = machine__nr_cpus_avail(machine);
/* Add a 1 page map for each CPU's entry trampoline */
for (cpu = 0; cpu < nr_cpus_avail; cpu++) {
u64 va = X86_64_CPU_ENTRY_AREA_PER_CPU +
cpu * X86_64_CPU_ENTRY_AREA_SIZE +
X86_64_ENTRY_TRAMPOLINE;
struct extra_kernel_map xm = {
.start = va,
.end = va + page_size,
.pgoff = pgoff,
};
strlcpy(xm.name, ENTRY_TRAMPOLINE_NAME, KMAP_NAME_LEN);
if (machine__create_extra_kernel_map(machine, kernel, &xm) < 0)
return -1;
}
machine->trampolines_mapped = nr_cpus_avail;
return 0;
}
int __weak machine__create_extra_kernel_maps(struct machine *machine __maybe_unused,
struct dso *kernel __maybe_unused)
{
return 0;
}
static int
__machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
{
/* In case of renewal the kernel map, destroy previous one */
machine__destroy_kernel_maps(machine);
map__put(machine->vmlinux_map);
machine->vmlinux_map = map__new2(0, kernel);
if (machine->vmlinux_map == NULL)
return -ENOMEM;
map__set_map_ip(machine->vmlinux_map, identity__map_ip);
map__set_unmap_ip(machine->vmlinux_map, identity__map_ip);
return maps__insert(machine__kernel_maps(machine), machine->vmlinux_map);
}
void machine__destroy_kernel_maps(struct machine *machine)
{
struct kmap *kmap;
struct map *map = machine__kernel_map(machine);
if (map == NULL)
return;
kmap = map__kmap(map);
maps__remove(machine__kernel_maps(machine), map);
if (kmap && kmap->ref_reloc_sym) {
zfree((char **)&kmap->ref_reloc_sym->name);
zfree(&kmap->ref_reloc_sym);
}
map__zput(machine->vmlinux_map);
}
int machines__create_guest_kernel_maps(struct machines *machines)
{
int ret = 0;
struct dirent **namelist = NULL;
int i, items = 0;
char path[PATH_MAX];
pid_t pid;
char *endp;
if (symbol_conf.default_guest_vmlinux_name ||
symbol_conf.default_guest_modules ||
symbol_conf.default_guest_kallsyms) {
machines__create_kernel_maps(machines, DEFAULT_GUEST_KERNEL_ID);
}
if (symbol_conf.guestmount) {
items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
if (items <= 0)
return -ENOENT;
for (i = 0; i < items; i++) {
if (!isdigit(namelist[i]->d_name[0])) {
/* Filter out . and .. */
continue;
}
pid = (pid_t)strtol(namelist[i]->d_name, &endp, 10);
if ((*endp != '\0') ||
(endp == namelist[i]->d_name) ||
(errno == ERANGE)) {
pr_debug("invalid directory (%s). Skipping.\n",
namelist[i]->d_name);
continue;
}
sprintf(path, "%s/%s/proc/kallsyms",
symbol_conf.guestmount,
namelist[i]->d_name);
ret = access(path, R_OK);
if (ret) {
pr_debug("Can't access file %s\n", path);
goto failure;
}
machines__create_kernel_maps(machines, pid);
}
failure:
free(namelist);
}
return ret;
}
void machines__destroy_kernel_maps(struct machines *machines)
{
struct rb_node *next = rb_first_cached(&machines->guests);
machine__destroy_kernel_maps(&machines->host);
while (next) {
struct machine *pos = rb_entry(next, struct machine, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_cached(&pos->rb_node, &machines->guests);
machine__delete(pos);
}
}
int machines__create_kernel_maps(struct machines *machines, pid_t pid)
{
struct machine *machine = machines__findnew(machines, pid);
if (machine == NULL)
return -1;
return machine__create_kernel_maps(machine);
}
int machine__load_kallsyms(struct machine *machine, const char *filename)
{
struct map *map = machine__kernel_map(machine);
struct dso *dso = map__dso(map);
int ret = __dso__load_kallsyms(dso, filename, map, true);
if (ret > 0) {
dso__set_loaded(dso);
/*
* Since /proc/kallsyms will have multiple sessions for the
* kernel, with modules between them, fixup the end of all
* sections.
*/
maps__fixup_end(machine__kernel_maps(machine));
}
return ret;
}
int machine__load_vmlinux_path(struct machine *machine)
{
struct map *map = machine__kernel_map(machine);
struct dso *dso = map__dso(map);
int ret = dso__load_vmlinux_path(dso, map);
if (ret > 0)
dso__set_loaded(dso);
return ret;
}
static char *get_kernel_version(const char *root_dir)
{
char version[PATH_MAX];
FILE *file;
char *name, *tmp;
const char *prefix = "Linux version ";
sprintf(version, "%s/proc/version", root_dir);
file = fopen(version, "r");
if (!file)
return NULL;
tmp = fgets(version, sizeof(version), file);
fclose(file);
if (!tmp)
return NULL;
name = strstr(version, prefix);
if (!name)
return NULL;
name += strlen(prefix);
tmp = strchr(name, ' ');
if (tmp)
*tmp = '\0';
return strdup(name);
}
static bool is_kmod_dso(struct dso *dso)
{
return dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
}
static int maps__set_module_path(struct maps *maps, const char *path, struct kmod_path *m)
{
char *long_name;
struct dso *dso;
struct map *map = maps__find_by_name(maps, m->name);
if (map == NULL)
return 0;
long_name = strdup(path);
if (long_name == NULL)
return -ENOMEM;
dso = map__dso(map);
dso__set_long_name(dso, long_name, true);
dso__kernel_module_get_build_id(dso, "");
/*
* Full name could reveal us kmod compression, so
* we need to update the symtab_type if needed.
*/
if (m->comp && is_kmod_dso(dso)) {
dso->symtab_type++;
dso->comp = m->comp;
}
return 0;
}
static int maps__set_modules_path_dir(struct maps *maps, const char *dir_name, int depth)
{
struct dirent *dent;
DIR *dir = opendir(dir_name);
int ret = 0;
if (!dir) {
pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
return -1;
}
while ((dent = readdir(dir)) != NULL) {
char path[PATH_MAX];
struct stat st;
/*sshfs might return bad dent->d_type, so we have to stat*/
path__join(path, sizeof(path), dir_name, dent->d_name);
if (stat(path, &st))
continue;
if (S_ISDIR(st.st_mode)) {
if (!strcmp(dent->d_name, ".") ||
!strcmp(dent->d_name, ".."))
continue;
/* Do not follow top-level source and build symlinks */
if (depth == 0) {
if (!strcmp(dent->d_name, "source") ||
!strcmp(dent->d_name, "build"))
continue;
}
ret = maps__set_modules_path_dir(maps, path, depth + 1);
if (ret < 0)
goto out;
} else {
struct kmod_path m;
ret = kmod_path__parse_name(&m, dent->d_name);
if (ret)
goto out;
if (m.kmod)
ret = maps__set_module_path(maps, path, &m);
zfree(&m.name);
if (ret)
goto out;
}
}
out:
closedir(dir);
return ret;
}
static int machine__set_modules_path(struct machine *machine)
{
char *version;
char modules_path[PATH_MAX];
version = get_kernel_version(machine->root_dir);
if (!version)
return -1;
snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s",
machine->root_dir, version);
free(version);
return maps__set_modules_path_dir(machine__kernel_maps(machine), modules_path, 0);
}
int __weak arch__fix_module_text_start(u64 *start __maybe_unused,
u64 *size __maybe_unused,
const char *name __maybe_unused)
{
return 0;
}
static int machine__create_module(void *arg, const char *name, u64 start,
u64 size)
{
struct machine *machine = arg;
struct map *map;
if (arch__fix_module_text_start(&start, &size, name) < 0)
return -1;
map = machine__addnew_module_map(machine, start, name);
if (map == NULL)
return -1;
map__set_end(map, start + size);
dso__kernel_module_get_build_id(map__dso(map), machine->root_dir);
map__put(map);
return 0;
}
static int machine__create_modules(struct machine *machine)
{
const char *modules;
char path[PATH_MAX];
if (machine__is_default_guest(machine)) {
modules = symbol_conf.default_guest_modules;
} else {
snprintf(path, PATH_MAX, "%s/proc/modules", machine->root_dir);
modules = path;
}
if (symbol__restricted_filename(modules, "/proc/modules"))
return -1;
if (modules__parse(modules, machine, machine__create_module))
return -1;
if (!machine__set_modules_path(machine))
return 0;
pr_debug("Problems setting modules path maps, continuing anyway...\n");
return 0;
}
static void machine__set_kernel_mmap(struct machine *machine,
u64 start, u64 end)
{
map__set_start(machine->vmlinux_map, start);
map__set_end(machine->vmlinux_map, end);
/*
* Be a bit paranoid here, some perf.data file came with
* a zero sized synthesized MMAP event for the kernel.
*/
if (start == 0 && end == 0)
map__set_end(machine->vmlinux_map, ~0ULL);
}
static int machine__update_kernel_mmap(struct machine *machine,
u64 start, u64 end)
{
struct map *orig, *updated;
int err;
orig = machine->vmlinux_map;
updated = map__get(orig);
machine->vmlinux_map = updated;
machine__set_kernel_mmap(machine, start, end);
maps__remove(machine__kernel_maps(machine), orig);
err = maps__insert(machine__kernel_maps(machine), updated);
map__put(orig);
return err;
}
int machine__create_kernel_maps(struct machine *machine)
{
struct dso *kernel = machine__get_kernel(machine);
const char *name = NULL;
u64 start = 0, end = ~0ULL;
int ret;
if (kernel == NULL)
return -1;
ret = __machine__create_kernel_maps(machine, kernel);
if (ret < 0)
goto out_put;
if (symbol_conf.use_modules && machine__create_modules(machine) < 0) {
if (machine__is_host(machine))
pr_debug("Problems creating module maps, "
"continuing anyway...\n");
else
pr_debug("Problems creating module maps for guest %d, "
"continuing anyway...\n", machine->pid);
}
if (!machine__get_running_kernel_start(machine, &name, &start, &end)) {
if (name &&
map__set_kallsyms_ref_reloc_sym(machine->vmlinux_map, name, start)) {
machine__destroy_kernel_maps(machine);
ret = -1;
goto out_put;
}
/*
* we have a real start address now, so re-order the kmaps
* assume it's the last in the kmaps
*/
ret = machine__update_kernel_mmap(machine, start, end);
if (ret < 0)
goto out_put;
}
if (machine__create_extra_kernel_maps(machine, kernel))
pr_debug("Problems creating extra kernel maps, continuing anyway...\n");
if (end == ~0ULL) {
/* update end address of the kernel map using adjacent module address */
struct map_rb_node *rb_node = maps__find_node(machine__kernel_maps(machine),
machine__kernel_map(machine));
struct map_rb_node *next = map_rb_node__next(rb_node);
if (next)
machine__set_kernel_mmap(machine, start, map__start(next->map));
}
out_put:
dso__put(kernel);
return ret;
}
static bool machine__uses_kcore(struct machine *machine)
{
struct dso *dso;
list_for_each_entry(dso, &machine->dsos.head, node) {
if (dso__is_kcore(dso))
return true;
}
return false;
}
static bool perf_event__is_extra_kernel_mmap(struct machine *machine,
struct extra_kernel_map *xm)
{
return machine__is(machine, "x86_64") &&
is_entry_trampoline(xm->name);
}
static int machine__process_extra_kernel_map(struct machine *machine,
struct extra_kernel_map *xm)
{
struct dso *kernel = machine__kernel_dso(machine);
if (kernel == NULL)
return -1;
return machine__create_extra_kernel_map(machine, kernel, xm);
}
static int machine__process_kernel_mmap_event(struct machine *machine,
struct extra_kernel_map *xm,
struct build_id *bid)
{
struct map *map;
enum dso_space_type dso_space;
bool is_kernel_mmap;
const char *mmap_name = machine->mmap_name;
/* If we have maps from kcore then we do not need or want any others */
if (machine__uses_kcore(machine))
return 0;
if (machine__is_host(machine))
dso_space = DSO_SPACE__KERNEL;
else
dso_space = DSO_SPACE__KERNEL_GUEST;
is_kernel_mmap = memcmp(xm->name, mmap_name, strlen(mmap_name) - 1) == 0;
if (!is_kernel_mmap && !machine__is_host(machine)) {
/*
* If the event was recorded inside the guest and injected into
* the host perf.data file, then it will match a host mmap_name,
* so try that - see machine__set_mmap_name().
*/
mmap_name = "[kernel.kallsyms]";
is_kernel_mmap = memcmp(xm->name, mmap_name, strlen(mmap_name) - 1) == 0;
}
if (xm->name[0] == '/' ||
(!is_kernel_mmap && xm->name[0] == '[')) {
map = machine__addnew_module_map(machine, xm->start,
xm->name);
if (map == NULL)
goto out_problem;
map__set_end(map, map__start(map) + xm->end - xm->start);
if (build_id__is_defined(bid))
dso__set_build_id(map__dso(map), bid);
} else if (is_kernel_mmap) {
const char *symbol_name = xm->name + strlen(mmap_name);
/*
* Should be there already, from the build-id table in
* the header.
*/
struct dso *kernel = NULL;
struct dso *dso;
down_read(&machine->dsos.lock);
list_for_each_entry(dso, &machine->dsos.head, node) {
/*
* The cpumode passed to is_kernel_module is not the
* cpumode of *this* event. If we insist on passing
* correct cpumode to is_kernel_module, we should
* record the cpumode when we adding this dso to the
* linked list.
*
* However we don't really need passing correct
* cpumode. We know the correct cpumode must be kernel
* mode (if not, we should not link it onto kernel_dsos
* list).
*
* Therefore, we pass PERF_RECORD_MISC_CPUMODE_UNKNOWN.
* is_kernel_module() treats it as a kernel cpumode.
*/
if (!dso->kernel ||
is_kernel_module(dso->long_name,
PERF_RECORD_MISC_CPUMODE_UNKNOWN))
continue;
kernel = dso;
break;
}
up_read(&machine->dsos.lock);
if (kernel == NULL)
kernel = machine__findnew_dso(machine, machine->mmap_name);
if (kernel == NULL)
goto out_problem;
kernel->kernel = dso_space;
if (__machine__create_kernel_maps(machine, kernel) < 0) {
dso__put(kernel);
goto out_problem;
}
if (strstr(kernel->long_name, "vmlinux"))
dso__set_short_name(kernel, "[kernel.vmlinux]", false);
if (machine__update_kernel_mmap(machine, xm->start, xm->end) < 0) {
dso__put(kernel);
goto out_problem;
}
if (build_id__is_defined(bid))
dso__set_build_id(kernel, bid);
/*
* Avoid using a zero address (kptr_restrict) for the ref reloc
* symbol. Effectively having zero here means that at record
* time /proc/sys/kernel/kptr_restrict was non zero.
*/
if (xm->pgoff != 0) {
map__set_kallsyms_ref_reloc_sym(machine->vmlinux_map,
symbol_name,
xm->pgoff);
}
if (machine__is_default_guest(machine)) {
/*
* preload dso of guest kernel and modules
*/
dso__load(kernel, machine__kernel_map(machine));
}
} else if (perf_event__is_extra_kernel_mmap(machine, xm)) {
return machine__process_extra_kernel_map(machine, xm);
}
return 0;
out_problem:
return -1;
}
int machine__process_mmap2_event(struct machine *machine,
union perf_event *event,
struct perf_sample *sample)
{
struct thread *thread;
struct map *map;
struct dso_id dso_id = {
.maj = event->mmap2.maj,
.min = event->mmap2.min,
.ino = event->mmap2.ino,
.ino_generation = event->mmap2.ino_generation,
};
struct build_id __bid, *bid = NULL;
int ret = 0;
if (dump_trace)
perf_event__fprintf_mmap2(event, stdout);
if (event->header.misc & PERF_RECORD_MISC_MMAP_BUILD_ID) {
bid = &__bid;
build_id__init(bid, event->mmap2.build_id, event->mmap2.build_id_size);
}
if (sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
sample->cpumode == PERF_RECORD_MISC_KERNEL) {
struct extra_kernel_map xm = {
.start = event->mmap2.start,
.end = event->mmap2.start + event->mmap2.len,
.pgoff = event->mmap2.pgoff,
};
strlcpy(xm.name, event->mmap2.filename, KMAP_NAME_LEN);
ret = machine__process_kernel_mmap_event(machine, &xm, bid);
if (ret < 0)
goto out_problem;
return 0;
}
thread = machine__findnew_thread(machine, event->mmap2.pid,
event->mmap2.tid);
if (thread == NULL)
goto out_problem;
map = map__new(machine, event->mmap2.start,
event->mmap2.len, event->mmap2.pgoff,
&dso_id, event->mmap2.prot,
event->mmap2.flags, bid,
event->mmap2.filename, thread);
if (map == NULL)
goto out_problem_map;
ret = thread__insert_map(thread, map);
if (ret)
goto out_problem_insert;
thread__put(thread);
map__put(map);
return 0;
out_problem_insert:
map__put(map);
out_problem_map:
thread__put(thread);
out_problem:
dump_printf("problem processing PERF_RECORD_MMAP2, skipping event.\n");
return 0;
}
int machine__process_mmap_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample)
{
struct thread *thread;
struct map *map;
u32 prot = 0;
int ret = 0;
if (dump_trace)
perf_event__fprintf_mmap(event, stdout);
if (sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
sample->cpumode == PERF_RECORD_MISC_KERNEL) {
struct extra_kernel_map xm = {
.start = event->mmap.start,
.end = event->mmap.start + event->mmap.len,
.pgoff = event->mmap.pgoff,
};
strlcpy(xm.name, event->mmap.filename, KMAP_NAME_LEN);
ret = machine__process_kernel_mmap_event(machine, &xm, NULL);
if (ret < 0)
goto out_problem;
return 0;
}
thread = machine__findnew_thread(machine, event->mmap.pid,
event->mmap.tid);
if (thread == NULL)
goto out_problem;
if (!(event->header.misc & PERF_RECORD_MISC_MMAP_DATA))
prot = PROT_EXEC;
map = map__new(machine, event->mmap.start,
event->mmap.len, event->mmap.pgoff,
NULL, prot, 0, NULL, event->mmap.filename, thread);
if (map == NULL)
goto out_problem_map;
ret = thread__insert_map(thread, map);
if (ret)
goto out_problem_insert;
thread__put(thread);
map__put(map);
return 0;
out_problem_insert:
map__put(map);
out_problem_map:
thread__put(thread);
out_problem:
dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
return 0;
}
static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock)
{
struct threads *threads = machine__threads(machine, th->tid);
if (threads->last_match == th)
threads__set_last_match(threads, NULL);
if (lock)
down_write(&threads->lock);
BUG_ON(refcount_read(&th->refcnt) == 0);
rb_erase_cached(&th->rb_node, &threads->entries);
RB_CLEAR_NODE(&th->rb_node);
--threads->nr;
/*
* Move it first to the dead_threads list, then drop the reference,
* if this is the last reference, then the thread__delete destructor
* will be called and we will remove it from the dead_threads list.
*/
list_add_tail(&th->node, &threads->dead);
/*
* We need to do the put here because if this is the last refcount,
* then we will be touching the threads->dead head when removing the
* thread.
*/
thread__put(th);
if (lock)
up_write(&threads->lock);
}
void machine__remove_thread(struct machine *machine, struct thread *th)
{
return __machine__remove_thread(machine, th, true);
}
int machine__process_fork_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample)
{
struct thread *thread = machine__find_thread(machine,
event->fork.pid,
event->fork.tid);
struct thread *parent = machine__findnew_thread(machine,
event->fork.ppid,
event->fork.ptid);
bool do_maps_clone = true;
int err = 0;
if (dump_trace)
perf_event__fprintf_task(event, stdout);
/*
* There may be an existing thread that is not actually the parent,
* either because we are processing events out of order, or because the
* (fork) event that would have removed the thread was lost. Assume the
* latter case and continue on as best we can.
*/
if (parent->pid_ != (pid_t)event->fork.ppid) {
dump_printf("removing erroneous parent thread %d/%d\n",
parent->pid_, parent->tid);
machine__remove_thread(machine, parent);
thread__put(parent);
parent = machine__findnew_thread(machine, event->fork.ppid,
event->fork.ptid);
}
/* if a thread currently exists for the thread id remove it */
if (thread != NULL) {
machine__remove_thread(machine, thread);
thread__put(thread);
}
thread = machine__findnew_thread(machine, event->fork.pid,
event->fork.tid);
/*
* When synthesizing FORK events, we are trying to create thread
* objects for the already running tasks on the machine.
*
* Normally, for a kernel FORK event, we want to clone the parent's
* maps because that is what the kernel just did.
*
* But when synthesizing, this should not be done. If we do, we end up
* with overlapping maps as we process the synthesized MMAP2 events that
* get delivered shortly thereafter.
*
* Use the FORK event misc flags in an internal way to signal this
* situation, so we can elide the map clone when appropriate.
*/
if (event->fork.header.misc & PERF_RECORD_MISC_FORK_EXEC)
do_maps_clone = false;
if (thread == NULL || parent == NULL ||
thread__fork(thread, parent, sample->time, do_maps_clone) < 0) {
dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
err = -1;
}
thread__put(thread);
thread__put(parent);
return err;
}
int machine__process_exit_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample __maybe_unused)
{
struct thread *thread = machine__find_thread(machine,
event->fork.pid,
event->fork.tid);
if (dump_trace)
perf_event__fprintf_task(event, stdout);
if (thread != NULL) {
thread__exited(thread);
thread__put(thread);
}
return 0;
}
int machine__process_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample)
{
int ret;
switch (event->header.type) {
case PERF_RECORD_COMM:
ret = machine__process_comm_event(machine, event, sample); break;
case PERF_RECORD_MMAP:
ret = machine__process_mmap_event(machine, event, sample); break;
case PERF_RECORD_NAMESPACES:
ret = machine__process_namespaces_event(machine, event, sample); break;
case PERF_RECORD_CGROUP:
ret = machine__process_cgroup_event(machine, event, sample); break;
case PERF_RECORD_MMAP2:
ret = machine__process_mmap2_event(machine, event, sample); break;
case PERF_RECORD_FORK:
ret = machine__process_fork_event(machine, event, sample); break;
case PERF_RECORD_EXIT:
ret = machine__process_exit_event(machine, event, sample); break;
case PERF_RECORD_LOST:
ret = machine__process_lost_event(machine, event, sample); break;
case PERF_RECORD_AUX:
ret = machine__process_aux_event(machine, event); break;
case PERF_RECORD_ITRACE_START:
ret = machine__process_itrace_start_event(machine, event); break;
case PERF_RECORD_LOST_SAMPLES:
ret = machine__process_lost_samples_event(machine, event, sample); break;
case PERF_RECORD_SWITCH:
case PERF_RECORD_SWITCH_CPU_WIDE:
ret = machine__process_switch_event(machine, event); break;
case PERF_RECORD_KSYMBOL:
ret = machine__process_ksymbol(machine, event, sample); break;
case PERF_RECORD_BPF_EVENT:
ret = machine__process_bpf(machine, event, sample); break;
case PERF_RECORD_TEXT_POKE:
ret = machine__process_text_poke(machine, event, sample); break;
case PERF_RECORD_AUX_OUTPUT_HW_ID:
ret = machine__process_aux_output_hw_id_event(machine, event); break;
default:
ret = -1;
break;
}
return ret;
}
static bool symbol__match_regex(struct symbol *sym, regex_t *regex)
{
if (!regexec(regex, sym->name, 0, NULL, 0))
return true;
return false;
}
static void ip__resolve_ams(struct thread *thread,
struct addr_map_symbol *ams,
u64 ip)
{
struct addr_location al;
memset(&al, 0, sizeof(al));
/*
* We cannot use the header.misc hint to determine whether a
* branch stack address is user, kernel, guest, hypervisor.
* Branches may straddle the kernel/user/hypervisor boundaries.
* Thus, we have to try consecutively until we find a match
* or else, the symbol is unknown
*/
thread__find_cpumode_addr_location(thread, ip, &al);
ams->addr = ip;
ams->al_addr = al.addr;
ams->al_level = al.level;
ams->ms.maps = al.maps;
ams->ms.sym = al.sym;
ams->ms.map = al.map;
ams->phys_addr = 0;
ams->data_page_size = 0;
}
static void ip__resolve_data(struct thread *thread,
u8 m, struct addr_map_symbol *ams,
u64 addr, u64 phys_addr, u64 daddr_page_size)
{
struct addr_location al;
memset(&al, 0, sizeof(al));
thread__find_symbol(thread, m, addr, &al);
ams->addr = addr;
ams->al_addr = al.addr;
ams->al_level = al.level;
ams->ms.maps = al.maps;
ams->ms.sym = al.sym;
ams->ms.map = al.map;
ams->phys_addr = phys_addr;
ams->data_page_size = daddr_page_size;
}
struct mem_info *sample__resolve_mem(struct perf_sample *sample,
struct addr_location *al)
{
struct mem_info *mi = mem_info__new();
if (!mi)
return NULL;
ip__resolve_ams(al->thread, &mi->iaddr, sample->ip);
ip__resolve_data(al->thread, al->cpumode, &mi->daddr,
sample->addr, sample->phys_addr,
sample->data_page_size);
mi->data_src.val = sample->data_src;
return mi;
}
static char *callchain_srcline(struct map_symbol *ms, u64 ip)
{
struct map *map = ms->map;
char *srcline = NULL;
struct dso *dso;
if (!map || callchain_param.key == CCKEY_FUNCTION)
return srcline;
dso = map__dso(map);
srcline = srcline__tree_find(&dso->srclines, ip);
if (!srcline) {
bool show_sym = false;
bool show_addr = callchain_param.key == CCKEY_ADDRESS;
srcline = get_srcline(dso, map__rip_2objdump(map, ip),
ms->sym, show_sym, show_addr, ip);
srcline__tree_insert(&dso->srclines, ip, srcline);
}
return srcline;
}
struct iterations {
int nr_loop_iter;
u64 cycles;
};
static int add_callchain_ip(struct thread *thread,
struct callchain_cursor *cursor,
struct symbol **parent,
struct addr_location *root_al,
u8 *cpumode,
u64 ip,
bool branch,
struct branch_flags *flags,
struct iterations *iter,
u64 branch_from)
{
struct map_symbol ms;
struct addr_location al;
int nr_loop_iter = 0, err;
u64 iter_cycles = 0;
const char *srcline = NULL;
al.filtered = 0;
al.sym = NULL;
al.srcline = NULL;
if (!cpumode) {
thread__find_cpumode_addr_location(thread, ip, &al);
} else {
if (ip >= PERF_CONTEXT_MAX) {
switch (ip) {
case PERF_CONTEXT_HV:
*cpumode = PERF_RECORD_MISC_HYPERVISOR;
break;
case PERF_CONTEXT_KERNEL:
*cpumode = PERF_RECORD_MISC_KERNEL;
break;
case PERF_CONTEXT_USER:
*cpumode = PERF_RECORD_MISC_USER;
break;
default:
pr_debug("invalid callchain context: "
"%"PRId64"\n", (s64) ip);
/*
* It seems the callchain is corrupted.
* Discard all.
*/
callchain_cursor_reset(cursor);
return 1;
}
return 0;
}
thread__find_symbol(thread, *cpumode, ip, &al);
}
if (al.sym != NULL) {
if (perf_hpp_list.parent && !*parent &&
symbol__match_regex(al.sym, &parent_regex))
*parent = al.sym;
else if (have_ignore_callees && root_al &&
symbol__match_regex(al.sym, &ignore_callees_regex)) {
/* Treat this symbol as the root,
forgetting its callees. */
*root_al = al;
callchain_cursor_reset(cursor);
}
}
if (symbol_conf.hide_unresolved && al.sym == NULL)
return 0;
if (iter) {
nr_loop_iter = iter->nr_loop_iter;
iter_cycles = iter->cycles;
}
ms.maps = al.maps;
ms.map = al.map;
ms.sym = al.sym;
if (!branch && append_inlines(cursor, &ms, ip) == 0)
return 0;
srcline = callchain_srcline(&ms, al.addr);
err = callchain_cursor_append(cursor, ip, &ms,
branch, flags, nr_loop_iter,
iter_cycles, branch_from, srcline);
map__put(al.map);
return err;
}
struct branch_info *sample__resolve_bstack(struct perf_sample *sample,
struct addr_location *al)
{
unsigned int i;
const struct branch_stack *bs = sample->branch_stack;
struct branch_entry *entries = perf_sample__branch_entries(sample);
struct branch_info *bi = calloc(bs->nr, sizeof(struct branch_info));
if (!bi)
return NULL;
for (i = 0; i < bs->nr; i++) {
ip__resolve_ams(al->thread, &bi[i].to, entries[i].to);
ip__resolve_ams(al->thread, &bi[i].from, entries[i].from);
bi[i].flags = entries[i].flags;
}
return bi;
}
static void save_iterations(struct iterations *iter,
struct branch_entry *be, int nr)
{
int i;
iter->nr_loop_iter++;
iter->cycles = 0;
for (i = 0; i < nr; i++)
iter->cycles += be[i].flags.cycles;
}
#define CHASHSZ 127
#define CHASHBITS 7
#define NO_ENTRY 0xff
#define PERF_MAX_BRANCH_DEPTH 127
/* Remove loops. */
static int remove_loops(struct branch_entry *l, int nr,
struct iterations *iter)
{
int i, j, off;
unsigned char chash[CHASHSZ];
memset(chash, NO_ENTRY, sizeof(chash));
BUG_ON(PERF_MAX_BRANCH_DEPTH > 255);
for (i = 0; i < nr; i++) {
int h = hash_64(l[i].from, CHASHBITS) % CHASHSZ;
/* no collision handling for now */
if (chash[h] == NO_ENTRY) {
chash[h] = i;
} else if (l[chash[h]].from == l[i].from) {
bool is_loop = true;
/* check if it is a real loop */
off = 0;
for (j = chash[h]; j < i && i + off < nr; j++, off++)
if (l[j].from != l[i + off].from) {
is_loop = false;
break;
}
if (is_loop) {
j = nr - (i + off);
if (j > 0) {
save_iterations(iter + i + off,
l + i, off);
memmove(iter + i, iter + i + off,
j * sizeof(*iter));
memmove(l + i, l + i + off,
j * sizeof(*l));
}
nr -= off;
}
}
}
return nr;
}
static int lbr_callchain_add_kernel_ip(struct thread *thread,
struct callchain_cursor *cursor,
struct perf_sample *sample,
struct symbol **parent,
struct addr_location *root_al,
u64 branch_from,
bool callee, int end)
{
struct ip_callchain *chain = sample->callchain;
u8 cpumode = PERF_RECORD_MISC_USER;
int err, i;
if (callee) {
for (i = 0; i < end + 1; i++) {
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, chain->ips[i],
false, NULL, NULL, branch_from);
if (err)
return err;
}
return 0;
}
for (i = end; i >= 0; i--) {
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, chain->ips[i],
false, NULL, NULL, branch_from);
if (err)
return err;
}
return 0;
}
static void save_lbr_cursor_node(struct thread *thread,
struct callchain_cursor *cursor,
int idx)
{
struct lbr_stitch *lbr_stitch = thread->lbr_stitch;
if (!lbr_stitch)
return;
if (cursor->pos == cursor->nr) {
lbr_stitch->prev_lbr_cursor[idx].valid = false;
return;
}
if (!cursor->curr)
cursor->curr = cursor->first;
else
cursor->curr = cursor->curr->next;
memcpy(&lbr_stitch->prev_lbr_cursor[idx], cursor->curr,
sizeof(struct callchain_cursor_node));
lbr_stitch->prev_lbr_cursor[idx].valid = true;
cursor->pos++;
}
static int lbr_callchain_add_lbr_ip(struct thread *thread,
struct callchain_cursor *cursor,
struct perf_sample *sample,
struct symbol **parent,
struct addr_location *root_al,
u64 *branch_from,
bool callee)
{
struct branch_stack *lbr_stack = sample->branch_stack;
struct branch_entry *entries = perf_sample__branch_entries(sample);
u8 cpumode = PERF_RECORD_MISC_USER;
int lbr_nr = lbr_stack->nr;
struct branch_flags *flags;
int err, i;
u64 ip;
/*
* The curr and pos are not used in writing session. They are cleared
* in callchain_cursor_commit() when the writing session is closed.
* Using curr and pos to track the current cursor node.
*/
if (thread->lbr_stitch) {
cursor->curr = NULL;
cursor->pos = cursor->nr;
if (cursor->nr) {
cursor->curr = cursor->first;
for (i = 0; i < (int)(cursor->nr - 1); i++)
cursor->curr = cursor->curr->next;
}
}
if (callee) {
/* Add LBR ip from first entries.to */
ip = entries[0].to;
flags = &entries[0].flags;
*branch_from = entries[0].from;
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, ip,
true, flags, NULL,
*branch_from);
if (err)
return err;
/*
* The number of cursor node increases.
* Move the current cursor node.
* But does not need to save current cursor node for entry 0.
* It's impossible to stitch the whole LBRs of previous sample.
*/
if (thread->lbr_stitch && (cursor->pos != cursor->nr)) {
if (!cursor->curr)
cursor->curr = cursor->first;
else
cursor->curr = cursor->curr->next;
cursor->pos++;
}
/* Add LBR ip from entries.from one by one. */
for (i = 0; i < lbr_nr; i++) {
ip = entries[i].from;
flags = &entries[i].flags;
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, ip,
true, flags, NULL,
*branch_from);
if (err)
return err;
save_lbr_cursor_node(thread, cursor, i);
}
return 0;
}
/* Add LBR ip from entries.from one by one. */
for (i = lbr_nr - 1; i >= 0; i--) {
ip = entries[i].from;
flags = &entries[i].flags;
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, ip,
true, flags, NULL,
*branch_from);
if (err)
return err;
save_lbr_cursor_node(thread, cursor, i);
}
/* Add LBR ip from first entries.to */
ip = entries[0].to;
flags = &entries[0].flags;
*branch_from = entries[0].from;
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, ip,
true, flags, NULL,
*branch_from);
if (err)
return err;
return 0;
}
static int lbr_callchain_add_stitched_lbr_ip(struct thread *thread,
struct callchain_cursor *cursor)
{
struct lbr_stitch *lbr_stitch = thread->lbr_stitch;
struct callchain_cursor_node *cnode;
struct stitch_list *stitch_node;
int err;
list_for_each_entry(stitch_node, &lbr_stitch->lists, node) {
cnode = &stitch_node->cursor;
err = callchain_cursor_append(cursor, cnode->ip,
&cnode->ms,
cnode->branch,
&cnode->branch_flags,
cnode->nr_loop_iter,
cnode->iter_cycles,
cnode->branch_from,
cnode->srcline);
if (err)
return err;
}
return 0;
}
static struct stitch_list *get_stitch_node(struct thread *thread)
{
struct lbr_stitch *lbr_stitch = thread->lbr_stitch;
struct stitch_list *stitch_node;
if (!list_empty(&lbr_stitch->free_lists)) {
stitch_node = list_first_entry(&lbr_stitch->free_lists,
struct stitch_list, node);
list_del(&stitch_node->node);
return stitch_node;
}
return malloc(sizeof(struct stitch_list));
}
static bool has_stitched_lbr(struct thread *thread,
struct perf_sample *cur,
struct perf_sample *prev,
unsigned int max_lbr,
bool callee)
{
struct branch_stack *cur_stack = cur->branch_stack;
struct branch_entry *cur_entries = perf_sample__branch_entries(cur);
struct branch_stack *prev_stack = prev->branch_stack;
struct branch_entry *prev_entries = perf_sample__branch_entries(prev);
struct lbr_stitch *lbr_stitch = thread->lbr_stitch;
int i, j, nr_identical_branches = 0;
struct stitch_list *stitch_node;
u64 cur_base, distance;
if (!cur_stack || !prev_stack)
return false;
/* Find the physical index of the base-of-stack for current sample. */
cur_base = max_lbr - cur_stack->nr + cur_stack->hw_idx + 1;
distance = (prev_stack->hw_idx > cur_base) ? (prev_stack->hw_idx - cur_base) :
(max_lbr + prev_stack->hw_idx - cur_base);
/* Previous sample has shorter stack. Nothing can be stitched. */
if (distance + 1 > prev_stack->nr)
return false;
/*
* Check if there are identical LBRs between two samples.
* Identical LBRs must have same from, to and flags values. Also,
* they have to be saved in the same LBR registers (same physical
* index).
*
* Starts from the base-of-stack of current sample.
*/
for (i = distance, j = cur_stack->nr - 1; (i >= 0) && (j >= 0); i--, j--) {
if ((prev_entries[i].from != cur_entries[j].from) ||
(prev_entries[i].to != cur_entries[j].to) ||
(prev_entries[i].flags.value != cur_entries[j].flags.value))
break;
nr_identical_branches++;
}
if (!nr_identical_branches)
return false;
/*
* Save the LBRs between the base-of-stack of previous sample
* and the base-of-stack of current sample into lbr_stitch->lists.
* These LBRs will be stitched later.
*/
for (i = prev_stack->nr - 1; i > (int)distance; i--) {
if (!lbr_stitch->prev_lbr_cursor[i].valid)
continue;
stitch_node = get_stitch_node(thread);
if (!stitch_node)
return false;
memcpy(&stitch_node->cursor, &lbr_stitch->prev_lbr_cursor[i],
sizeof(struct callchain_cursor_node));
if (callee)
list_add(&stitch_node->node, &lbr_stitch->lists);
else
list_add_tail(&stitch_node->node, &lbr_stitch->lists);
}
return true;
}
static bool alloc_lbr_stitch(struct thread *thread, unsigned int max_lbr)
{
if (thread->lbr_stitch)
return true;
thread->lbr_stitch = zalloc(sizeof(*thread->lbr_stitch));
if (!thread->lbr_stitch)
goto err;
thread->lbr_stitch->prev_lbr_cursor = calloc(max_lbr + 1, sizeof(struct callchain_cursor_node));
if (!thread->lbr_stitch->prev_lbr_cursor)
goto free_lbr_stitch;
INIT_LIST_HEAD(&thread->lbr_stitch->lists);
INIT_LIST_HEAD(&thread->lbr_stitch->free_lists);
return true;
free_lbr_stitch:
zfree(&thread->lbr_stitch);
err:
pr_warning("Failed to allocate space for stitched LBRs. Disable LBR stitch\n");
thread->lbr_stitch_enable = false;
return false;
}
/*
* Resolve LBR callstack chain sample
* Return:
* 1 on success get LBR callchain information
* 0 no available LBR callchain information, should try fp
* negative error code on other errors.
*/
static int resolve_lbr_callchain_sample(struct thread *thread,
struct callchain_cursor *cursor,
struct perf_sample *sample,
struct symbol **parent,
struct addr_location *root_al,
int max_stack,
unsigned int max_lbr)
{
bool callee = (callchain_param.order == ORDER_CALLEE);
struct ip_callchain *chain = sample->callchain;
int chain_nr = min(max_stack, (int)chain->nr), i;
struct lbr_stitch *lbr_stitch;
bool stitched_lbr = false;
u64 branch_from = 0;
int err;
for (i = 0; i < chain_nr; i++) {
if (chain->ips[i] == PERF_CONTEXT_USER)
break;
}
/* LBR only affects the user callchain */
if (i == chain_nr)
return 0;
if (thread->lbr_stitch_enable && !sample->no_hw_idx &&
(max_lbr > 0) && alloc_lbr_stitch(thread, max_lbr)) {
lbr_stitch = thread->lbr_stitch;
stitched_lbr = has_stitched_lbr(thread, sample,
&lbr_stitch->prev_sample,
max_lbr, callee);
if (!stitched_lbr && !list_empty(&lbr_stitch->lists)) {
list_replace_init(&lbr_stitch->lists,
&lbr_stitch->free_lists);
}
memcpy(&lbr_stitch->prev_sample, sample, sizeof(*sample));
}
if (callee) {
/* Add kernel ip */
err = lbr_callchain_add_kernel_ip(thread, cursor, sample,
parent, root_al, branch_from,
true, i);
if (err)
goto error;
err = lbr_callchain_add_lbr_ip(thread, cursor, sample, parent,
root_al, &branch_from, true);
if (err)
goto error;
if (stitched_lbr) {
err = lbr_callchain_add_stitched_lbr_ip(thread, cursor);
if (err)
goto error;
}
} else {
if (stitched_lbr) {
err = lbr_callchain_add_stitched_lbr_ip(thread, cursor);
if (err)
goto error;
}
err = lbr_callchain_add_lbr_ip(thread, cursor, sample, parent,
root_al, &branch_from, false);
if (err)
goto error;
/* Add kernel ip */
err = lbr_callchain_add_kernel_ip(thread, cursor, sample,
parent, root_al, branch_from,
false, i);
if (err)
goto error;
}
return 1;
error:
return (err < 0) ? err : 0;
}
static int find_prev_cpumode(struct ip_callchain *chain, struct thread *thread,
struct callchain_cursor *cursor,
struct symbol **parent,
struct addr_location *root_al,
u8 *cpumode, int ent)
{
int err = 0;
while (--ent >= 0) {
u64 ip = chain->ips[ent];
if (ip >= PERF_CONTEXT_MAX) {
err = add_callchain_ip(thread, cursor, parent,
root_al, cpumode, ip,
false, NULL, NULL, 0);
break;
}
}
return err;
}
static u64 get_leaf_frame_caller(struct perf_sample *sample,
struct thread *thread, int usr_idx)
{
if (machine__normalized_is(maps__machine(thread->maps), "arm64"))
return get_leaf_frame_caller_aarch64(sample, thread, usr_idx);
else
return 0;
}
static int thread__resolve_callchain_sample(struct thread *thread,
struct callchain_cursor *cursor,
struct evsel *evsel,
struct perf_sample *sample,
struct symbol **parent,
struct addr_location *root_al,
int max_stack)
{
struct branch_stack *branch = sample->branch_stack;
struct branch_entry *entries = perf_sample__branch_entries(sample);
struct ip_callchain *chain = sample->callchain;
int chain_nr = 0;
u8 cpumode = PERF_RECORD_MISC_USER;
int i, j, err, nr_entries, usr_idx;
int skip_idx = -1;
int first_call = 0;
u64 leaf_frame_caller;
if (chain)
chain_nr = chain->nr;
if (evsel__has_branch_callstack(evsel)) {
struct perf_env *env = evsel__env(evsel);
err = resolve_lbr_callchain_sample(thread, cursor, sample, parent,
root_al, max_stack,
!env ? 0 : env->max_branches);
if (err)
return (err < 0) ? err : 0;
}
/*
* Based on DWARF debug information, some architectures skip
* a callchain entry saved by the kernel.
*/
skip_idx = arch_skip_callchain_idx(thread, chain);
/*
* Add branches to call stack for easier browsing. This gives
* more context for a sample than just the callers.
*
* This uses individual histograms of paths compared to the
* aggregated histograms the normal LBR mode uses.
*
* Limitations for now:
* - No extra filters
* - No annotations (should annotate somehow)
*/
if (branch && callchain_param.branch_callstack) {
int nr = min(max_stack, (int)branch->nr);
struct branch_entry be[nr];
struct iterations iter[nr];
if (branch->nr > PERF_MAX_BRANCH_DEPTH) {
pr_warning("corrupted branch chain. skipping...\n");
goto check_calls;
}
for (i = 0; i < nr; i++) {
if (callchain_param.order == ORDER_CALLEE) {
be[i] = entries[i];
if (chain == NULL)
continue;
/*
* Check for overlap into the callchain.
* The return address is one off compared to
* the branch entry. To adjust for this
* assume the calling instruction is not longer
* than 8 bytes.
*/
if (i == skip_idx ||
chain->ips[first_call] >= PERF_CONTEXT_MAX)
first_call++;
else if (be[i].from < chain->ips[first_call] &&
be[i].from >= chain->ips[first_call] - 8)
first_call++;
} else
be[i] = entries[branch->nr - i - 1];
}
memset(iter, 0, sizeof(struct iterations) * nr);
nr = remove_loops(be, nr, iter);
for (i = 0; i < nr; i++) {
err = add_callchain_ip(thread, cursor, parent,
root_al,
NULL, be[i].to,
true, &be[i].flags,
NULL, be[i].from);
if (!err)
err = add_callchain_ip(thread, cursor, parent, root_al,
NULL, be[i].from,
true, &be[i].flags,
&iter[i], 0);
if (err == -EINVAL)
break;
if (err)
return err;
}
if (chain_nr == 0)
return 0;
chain_nr -= nr;
}
check_calls:
if (chain && callchain_param.order != ORDER_CALLEE) {
err = find_prev_cpumode(chain, thread, cursor, parent, root_al,
&cpumode, chain->nr - first_call);
if (err)
return (err < 0) ? err : 0;
}
for (i = first_call, nr_entries = 0;
i < chain_nr && nr_entries < max_stack; i++) {
u64 ip;
if (callchain_param.order == ORDER_CALLEE)
j = i;
else
j = chain->nr - i - 1;
#ifdef HAVE_SKIP_CALLCHAIN_IDX
if (j == skip_idx)
continue;
#endif
ip = chain->ips[j];
if (ip < PERF_CONTEXT_MAX)
++nr_entries;
else if (callchain_param.order != ORDER_CALLEE) {
err = find_prev_cpumode(chain, thread, cursor, parent,
root_al, &cpumode, j);
if (err)
return (err < 0) ? err : 0;
continue;
}
/*
* PERF_CONTEXT_USER allows us to locate where the user stack ends.
* Depending on callchain_param.order and the position of PERF_CONTEXT_USER,
* the index will be different in order to add the missing frame
* at the right place.
*/
usr_idx = callchain_param.order == ORDER_CALLEE ? j-2 : j-1;
if (usr_idx >= 0 && chain->ips[usr_idx] == PERF_CONTEXT_USER) {
leaf_frame_caller = get_leaf_frame_caller(sample, thread, usr_idx);
/*
* check if leaf_frame_Caller != ip to not add the same
* value twice.
*/
if (leaf_frame_caller && leaf_frame_caller != ip) {
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, leaf_frame_caller,
false, NULL, NULL, 0);
if (err)
return (err < 0) ? err : 0;
}
}
err = add_callchain_ip(thread, cursor, parent,
root_al, &cpumode, ip,
false, NULL, NULL, 0);
if (err)
return (err < 0) ? err : 0;
}
return 0;
}
static int append_inlines(struct callchain_cursor *cursor, struct map_symbol *ms, u64 ip)
{
struct symbol *sym = ms->sym;
struct map *map = ms->map;
struct inline_node *inline_node;
struct inline_list *ilist;
struct dso *dso;
u64 addr;
int ret = 1;
if (!symbol_conf.inline_name || !map || !sym)
return ret;
addr = map__dso_map_ip(map, ip);
addr = map__rip_2objdump(map, addr);
dso = map__dso(map);
inline_node = inlines__tree_find(&dso->inlined_nodes, addr);
if (!inline_node) {
inline_node = dso__parse_addr_inlines(dso, addr, sym);
if (!inline_node)
return ret;
inlines__tree_insert(&dso->inlined_nodes, inline_node);
}
list_for_each_entry(ilist, &inline_node->val, list) {
struct map_symbol ilist_ms = {
.maps = ms->maps,
.map = map,
.sym = ilist->symbol,
};
ret = callchain_cursor_append(cursor, ip, &ilist_ms, false,
NULL, 0, 0, 0, ilist->srcline);
if (ret != 0)
return ret;
}
return ret;
}
static int unwind_entry(struct unwind_entry *entry, void *arg)
{
struct callchain_cursor *cursor = arg;
const char *srcline = NULL;
u64 addr = entry->ip;
if (symbol_conf.hide_unresolved && entry->ms.sym == NULL)
return 0;
if (append_inlines(cursor, &entry->ms, entry->ip) == 0)
return 0;
/*
* Convert entry->ip from a virtual address to an offset in
* its corresponding binary.
*/
if (entry->ms.map)
addr = map__dso_map_ip(entry->ms.map, entry->ip);
srcline = callchain_srcline(&entry->ms, addr);
return callchain_cursor_append(cursor, entry->ip, &entry->ms,
false, NULL, 0, 0, 0, srcline);
}
static int thread__resolve_callchain_unwind(struct thread *thread,
struct callchain_cursor *cursor,
struct evsel *evsel,
struct perf_sample *sample,
int max_stack)
{
/* Can we do dwarf post unwind? */
if (!((evsel->core.attr.sample_type & PERF_SAMPLE_REGS_USER) &&
(evsel->core.attr.sample_type & PERF_SAMPLE_STACK_USER)))
return 0;
/* Bail out if nothing was captured. */
if ((!sample->user_regs.regs) ||
(!sample->user_stack.size))
return 0;
return unwind__get_entries(unwind_entry, cursor,
thread, sample, max_stack, false);
}
int thread__resolve_callchain(struct thread *thread,
struct callchain_cursor *cursor,
struct evsel *evsel,
struct perf_sample *sample,
struct symbol **parent,
struct addr_location *root_al,
int max_stack)
{
int ret = 0;
callchain_cursor_reset(cursor);
if (callchain_param.order == ORDER_CALLEE) {
ret = thread__resolve_callchain_sample(thread, cursor,
evsel, sample,
parent, root_al,
max_stack);
if (ret)
return ret;
ret = thread__resolve_callchain_unwind(thread, cursor,
evsel, sample,
max_stack);
} else {
ret = thread__resolve_callchain_unwind(thread, cursor,
evsel, sample,
max_stack);
if (ret)
return ret;
ret = thread__resolve_callchain_sample(thread, cursor,
evsel, sample,
parent, root_al,
max_stack);
}
return ret;
}
int machine__for_each_thread(struct machine *machine,
int (*fn)(struct thread *thread, void *p),
void *priv)
{
struct threads *threads;
struct rb_node *nd;
struct thread *thread;
int rc = 0;
int i;
for (i = 0; i < THREADS__TABLE_SIZE; i++) {
threads = &machine->threads[i];
for (nd = rb_first_cached(&threads->entries); nd;
nd = rb_next(nd)) {
thread = rb_entry(nd, struct thread, rb_node);
rc = fn(thread, priv);
if (rc != 0)
return rc;
}
list_for_each_entry(thread, &threads->dead, node) {
rc = fn(thread, priv);
if (rc != 0)
return rc;
}
}
return rc;
}
int machines__for_each_thread(struct machines *machines,
int (*fn)(struct thread *thread, void *p),
void *priv)
{
struct rb_node *nd;
int rc = 0;
rc = machine__for_each_thread(&machines->host, fn, priv);
if (rc != 0)
return rc;
for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
struct machine *machine = rb_entry(nd, struct machine, rb_node);
rc = machine__for_each_thread(machine, fn, priv);
if (rc != 0)
return rc;
}
return rc;
}
pid_t machine__get_current_tid(struct machine *machine, int cpu)
{
if (cpu < 0 || (size_t)cpu >= machine->current_tid_sz)
return -1;
return machine->current_tid[cpu];
}
int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
pid_t tid)
{
struct thread *thread;
const pid_t init_val = -1;
if (cpu < 0)
return -EINVAL;
if (realloc_array_as_needed(machine->current_tid,
machine->current_tid_sz,
(unsigned int)cpu,
&init_val))
return -ENOMEM;
machine->current_tid[cpu] = tid;
thread = machine__findnew_thread(machine, pid, tid);
if (!thread)
return -ENOMEM;
thread->cpu = cpu;
thread__put(thread);
return 0;
}
/*
* Compares the raw arch string. N.B. see instead perf_env__arch() or
* machine__normalized_is() if a normalized arch is needed.
*/
bool machine__is(struct machine *machine, const char *arch)
{
return machine && !strcmp(perf_env__raw_arch(machine->env), arch);
}
bool machine__normalized_is(struct machine *machine, const char *arch)
{
return machine && !strcmp(perf_env__arch(machine->env), arch);
}
int machine__nr_cpus_avail(struct machine *machine)
{
return machine ? perf_env__nr_cpus_avail(machine->env) : 0;
}
int machine__get_kernel_start(struct machine *machine)
{
struct map *map = machine__kernel_map(machine);
int err = 0;
/*
* The only addresses above 2^63 are kernel addresses of a 64-bit
* kernel. Note that addresses are unsigned so that on a 32-bit system
* all addresses including kernel addresses are less than 2^32. In
* that case (32-bit system), if the kernel mapping is unknown, all
* addresses will be assumed to be in user space - see
* machine__kernel_ip().
*/
machine->kernel_start = 1ULL << 63;
if (map) {
err = map__load(map);
/*
* On x86_64, PTI entry trampolines are less than the
* start of kernel text, but still above 2^63. So leave
* kernel_start = 1ULL << 63 for x86_64.
*/
if (!err && !machine__is(machine, "x86_64"))
machine->kernel_start = map__start(map);
}
return err;
}
u8 machine__addr_cpumode(struct machine *machine, u8 cpumode, u64 addr)
{
u8 addr_cpumode = cpumode;
bool kernel_ip;
if (!machine->single_address_space)
goto out;
kernel_ip = machine__kernel_ip(machine, addr);
switch (cpumode) {
case PERF_RECORD_MISC_KERNEL:
case PERF_RECORD_MISC_USER:
addr_cpumode = kernel_ip ? PERF_RECORD_MISC_KERNEL :
PERF_RECORD_MISC_USER;
break;
case PERF_RECORD_MISC_GUEST_KERNEL:
case PERF_RECORD_MISC_GUEST_USER:
addr_cpumode = kernel_ip ? PERF_RECORD_MISC_GUEST_KERNEL :
PERF_RECORD_MISC_GUEST_USER;
break;
default:
break;
}
out:
return addr_cpumode;
}
struct dso *machine__findnew_dso_id(struct machine *machine, const char *filename, struct dso_id *id)
{
return dsos__findnew_id(&machine->dsos, filename, id);
}
struct dso *machine__findnew_dso(struct machine *machine, const char *filename)
{
return machine__findnew_dso_id(machine, filename, NULL);
}
char *machine__resolve_kernel_addr(void *vmachine, unsigned long long *addrp, char **modp)
{
struct machine *machine = vmachine;
struct map *map;
struct symbol *sym = machine__find_kernel_symbol(machine, *addrp, &map);
if (sym == NULL)
return NULL;
*modp = __map__is_kmodule(map) ? (char *)map__dso(map)->short_name : NULL;
*addrp = map__unmap_ip(map, sym->start);
return sym->name;
}
int machine__for_each_dso(struct machine *machine, machine__dso_t fn, void *priv)
{
struct dso *pos;
int err = 0;
list_for_each_entry(pos, &machine->dsos.head, node) {
if (fn(pos, machine, priv))
err = -1;
}
return err;
}
int machine__for_each_kernel_map(struct machine *machine, machine__map_t fn, void *priv)
{
struct maps *maps = machine__kernel_maps(machine);
struct map_rb_node *pos;
int err = 0;
maps__for_each_entry(maps, pos) {
err = fn(pos->map, priv);
if (err != 0) {
break;
}
}
return err;
}
bool machine__is_lock_function(struct machine *machine, u64 addr)
{
if (!machine->sched.text_start) {
struct map *kmap;
struct symbol *sym = machine__find_kernel_symbol_by_name(machine, "__sched_text_start", &kmap);
if (!sym) {
/* to avoid retry */
machine->sched.text_start = 1;
return false;
}
machine->sched.text_start = map__unmap_ip(kmap, sym->start);
/* should not fail from here */
sym = machine__find_kernel_symbol_by_name(machine, "__sched_text_end", &kmap);
machine->sched.text_end = map__unmap_ip(kmap, sym->start);
sym = machine__find_kernel_symbol_by_name(machine, "__lock_text_start", &kmap);
machine->lock.text_start = map__unmap_ip(kmap, sym->start);
sym = machine__find_kernel_symbol_by_name(machine, "__lock_text_end", &kmap);
machine->lock.text_end = map__unmap_ip(kmap, sym->start);
}
/* failed to get kernel symbols */
if (machine->sched.text_start == 1)
return false;
/* mutex and rwsem functions are in sched text section */
if (machine->sched.text_start <= addr && addr < machine->sched.text_end)
return true;
/* spinlock functions are in lock text section */
if (machine->lock.text_start <= addr && addr < machine->lock.text_end)
return true;
return false;
}
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