android_kernel_xiaomi_sm8350/tools/perf/util/event.c
Arnaldo Carvalho de Melo 56b03f3c4d perf tools: Handle relocatable kernels
DSOs don't have this problem because the kernel emits a
PERF_MMAP for each new executable mapping it performs on
monitored threads.

To fix the kernel case we simulate the same behaviour, by having
'perf record' to synthesize a PERF_MMAP for the kernel, encoded
like this:

[root@doppio ~]# perf record -a -f sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.344 MB perf.data (~15038 samples) ]
[root@doppio ~]# perf report -D | head -10

0xd0 [0x40]: event: 1
.
. ... raw event: size 64 bytes
.  0000:  01 00 00 00 00 00 40 00 00 00 00 00 00 00 00 00 ......@........
.  0010:  00 00 00 81 ff ff ff ff 00 00 00 00 00 00 00 00 ...............
.  0020:  00 00 00 00 00 00 00 00 5b 6b 65 72 6e 65 6c 2e ........  [kernel
.  0030:  6b 61 6c 6c 73 79 6d 73 2e 5f 74 65 78 74 5d 00  kallsyms._text]
.  0xd0
[0x40]: PERF_RECORD_MMAP 0/0: [0xffffffff81000000((nil)) @ (nil)]: [kernel.kallsyms._text]

I.e. we identify such event as having:

 .pid      = 0
 .filename = [kernel.kallsyms.REFNAME]
 .start    = REFNAME addr in /proc/kallsyms at 'perf record' time

and use now a hardcoded value of '.text' for REFNAME.

Then, later, in 'perf report', if there are any kernel hits and
thus we need to resolve kernel symbols, we search for REFNAME
and if its address changed, relocation happened and we thus must
change the kernel mapping routines to one that uses .pgoff as
the relocation to apply.

This way we use the same mechanism used for the other DSOs and
don't have to do a two pass in all the kernel symbols.

Reported-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
LKML-Reference: <1262717431-1246-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:11 +01:00

515 lines
12 KiB
C

#include <linux/types.h>
#include "event.h"
#include "debug.h"
#include "session.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
static pid_t event__synthesize_comm(pid_t pid, int full,
int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session)
{
event_t ev;
char filename[PATH_MAX];
char bf[BUFSIZ];
FILE *fp;
size_t size = 0;
DIR *tasks;
struct dirent dirent, *next;
pid_t tgid = 0;
snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
fp = fopen(filename, "r");
if (fp == NULL) {
out_race:
/*
* We raced with a task exiting - just return:
*/
pr_debug("couldn't open %s\n", filename);
return 0;
}
memset(&ev.comm, 0, sizeof(ev.comm));
while (!ev.comm.comm[0] || !ev.comm.pid) {
if (fgets(bf, sizeof(bf), fp) == NULL)
goto out_failure;
if (memcmp(bf, "Name:", 5) == 0) {
char *name = bf + 5;
while (*name && isspace(*name))
++name;
size = strlen(name) - 1;
memcpy(ev.comm.comm, name, size++);
} else if (memcmp(bf, "Tgid:", 5) == 0) {
char *tgids = bf + 5;
while (*tgids && isspace(*tgids))
++tgids;
tgid = ev.comm.pid = atoi(tgids);
}
}
ev.comm.header.type = PERF_RECORD_COMM;
size = ALIGN(size, sizeof(u64));
ev.comm.header.size = sizeof(ev.comm) - (sizeof(ev.comm.comm) - size);
if (!full) {
ev.comm.tid = pid;
process(&ev, session);
goto out_fclose;
}
snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
tasks = opendir(filename);
if (tasks == NULL)
goto out_race;
while (!readdir_r(tasks, &dirent, &next) && next) {
char *end;
pid = strtol(dirent.d_name, &end, 10);
if (*end)
continue;
ev.comm.tid = pid;
process(&ev, session);
}
closedir(tasks);
out_fclose:
fclose(fp);
return tgid;
out_failure:
pr_warning("couldn't get COMM and pgid, malformed %s\n", filename);
return -1;
}
static int event__synthesize_mmap_events(pid_t pid, pid_t tgid,
int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session)
{
char filename[PATH_MAX];
FILE *fp;
snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
fp = fopen(filename, "r");
if (fp == NULL) {
/*
* We raced with a task exiting - just return:
*/
pr_debug("couldn't open %s\n", filename);
return -1;
}
while (1) {
char bf[BUFSIZ], *pbf = bf;
event_t ev = {
.header = { .type = PERF_RECORD_MMAP },
};
int n;
size_t size;
if (fgets(bf, sizeof(bf), fp) == NULL)
break;
/* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
n = hex2u64(pbf, &ev.mmap.start);
if (n < 0)
continue;
pbf += n + 1;
n = hex2u64(pbf, &ev.mmap.len);
if (n < 0)
continue;
pbf += n + 3;
if (*pbf == 'x') { /* vm_exec */
char *execname = strchr(bf, '/');
/* Catch VDSO */
if (execname == NULL)
execname = strstr(bf, "[vdso]");
if (execname == NULL)
continue;
size = strlen(execname);
execname[size - 1] = '\0'; /* Remove \n */
memcpy(ev.mmap.filename, execname, size);
size = ALIGN(size, sizeof(u64));
ev.mmap.len -= ev.mmap.start;
ev.mmap.header.size = (sizeof(ev.mmap) -
(sizeof(ev.mmap.filename) - size));
ev.mmap.pid = tgid;
ev.mmap.tid = pid;
process(&ev, session);
}
}
fclose(fp);
return 0;
}
int event__synthesize_thread(pid_t pid,
int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session)
{
pid_t tgid = event__synthesize_comm(pid, 1, process, session);
if (tgid == -1)
return -1;
return event__synthesize_mmap_events(pid, tgid, process, session);
}
void event__synthesize_threads(int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session)
{
DIR *proc;
struct dirent dirent, *next;
proc = opendir("/proc");
while (!readdir_r(proc, &dirent, &next) && next) {
char *end;
pid_t pid = strtol(dirent.d_name, &end, 10);
if (*end) /* only interested in proper numerical dirents */
continue;
event__synthesize_thread(pid, process, session);
}
closedir(proc);
}
struct process_symbol_args {
const char *name;
u64 start;
};
static int find_symbol_cb(void *arg, const char *name, char type, u64 start)
{
struct process_symbol_args *args = arg;
if (!symbol_type__is_a(type, MAP__FUNCTION) || strcmp(name, args->name))
return 0;
args->start = start;
return 1;
}
int event__synthesize_kernel_mmap(int (*process)(event_t *event,
struct perf_session *session),
struct perf_session *session,
const char *symbol_name)
{
size_t size;
event_t ev = {
.header = { .type = PERF_RECORD_MMAP },
};
/*
* We should get this from /sys/kernel/sections/.text, but till that is
* available use this, and after it is use this as a fallback for older
* kernels.
*/
struct process_symbol_args args = { .name = symbol_name, };
if (kallsyms__parse(&args, find_symbol_cb) <= 0)
return -ENOENT;
size = snprintf(ev.mmap.filename, sizeof(ev.mmap.filename),
"[kernel.kallsyms.%s]", symbol_name) + 1;
size = ALIGN(size, sizeof(u64));
ev.mmap.header.size = (sizeof(ev.mmap) - (sizeof(ev.mmap.filename) - size));
ev.mmap.start = args.start;
return process(&ev, session);
}
static void thread__comm_adjust(struct thread *self)
{
char *comm = self->comm;
if (!symbol_conf.col_width_list_str && !symbol_conf.field_sep &&
(!symbol_conf.comm_list ||
strlist__has_entry(symbol_conf.comm_list, comm))) {
unsigned int slen = strlen(comm);
if (slen > comms__col_width) {
comms__col_width = slen;
threads__col_width = slen + 6;
}
}
}
static int thread__set_comm_adjust(struct thread *self, const char *comm)
{
int ret = thread__set_comm(self, comm);
if (ret)
return ret;
thread__comm_adjust(self);
return 0;
}
int event__process_comm(event_t *self, struct perf_session *session)
{
struct thread *thread = perf_session__findnew(session, self->comm.pid);
dump_printf(": %s:%d\n", self->comm.comm, self->comm.pid);
if (thread == NULL || thread__set_comm_adjust(thread, self->comm.comm)) {
dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
return -1;
}
return 0;
}
int event__process_lost(event_t *self, struct perf_session *session)
{
dump_printf(": id:%Ld: lost:%Ld\n", self->lost.id, self->lost.lost);
session->events_stats.lost += self->lost.lost;
return 0;
}
int event__process_mmap(event_t *self, struct perf_session *session)
{
struct thread *thread;
struct map *map;
static const char kmmap_prefix[] = "[kernel.kallsyms.";
dump_printf(" %d/%d: [%p(%p) @ %p]: %s\n",
self->mmap.pid, self->mmap.tid,
(void *)(long)self->mmap.start,
(void *)(long)self->mmap.len,
(void *)(long)self->mmap.pgoff,
self->mmap.filename);
if (self->mmap.pid == 0 &&
memcmp(self->mmap.filename, kmmap_prefix,
sizeof(kmmap_prefix) - 1) == 0) {
const char *symbol_name = (self->mmap.filename +
sizeof(kmmap_prefix) - 1);
perf_session__set_kallsyms_ref_reloc_sym(session, symbol_name,
self->mmap.start);
return 0;
}
thread = perf_session__findnew(session, self->mmap.pid);
map = map__new(&self->mmap, MAP__FUNCTION,
session->cwd, session->cwdlen);
if (thread == NULL || map == NULL)
dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
else
thread__insert_map(thread, map);
return 0;
}
int event__process_task(event_t *self, struct perf_session *session)
{
struct thread *thread = perf_session__findnew(session, self->fork.pid);
struct thread *parent = perf_session__findnew(session, self->fork.ppid);
dump_printf("(%d:%d):(%d:%d)\n", self->fork.pid, self->fork.tid,
self->fork.ppid, self->fork.ptid);
/*
* A thread clone will have the same PID for both parent and child.
*/
if (thread == parent)
return 0;
if (self->header.type == PERF_RECORD_EXIT)
return 0;
if (thread == NULL || parent == NULL ||
thread__fork(thread, parent) < 0) {
dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
return -1;
}
return 0;
}
void thread__find_addr_location(struct thread *self,
struct perf_session *session, u8 cpumode,
enum map_type type, u64 addr,
struct addr_location *al,
symbol_filter_t filter)
{
struct map_groups *mg = &self->mg;
al->thread = self;
al->addr = addr;
if (cpumode & PERF_RECORD_MISC_KERNEL) {
al->level = 'k';
mg = &session->kmaps;
} else if (cpumode & PERF_RECORD_MISC_USER)
al->level = '.';
else {
al->level = 'H';
al->map = NULL;
al->sym = NULL;
return;
}
try_again:
al->map = map_groups__find(mg, type, al->addr);
if (al->map == NULL) {
/*
* If this is outside of all known maps, and is a negative
* address, try to look it up in the kernel dso, as it might be
* a vsyscall or vdso (which executes in user-mode).
*
* XXX This is nasty, we should have a symbol list in the
* "[vdso]" dso, but for now lets use the old trick of looking
* in the whole kernel symbol list.
*/
if ((long long)al->addr < 0 && mg != &session->kmaps) {
mg = &session->kmaps;
goto try_again;
}
al->sym = NULL;
} else {
al->addr = al->map->map_ip(al->map, al->addr);
al->sym = map__find_symbol(al->map, session, al->addr, filter);
}
}
static void dso__calc_col_width(struct dso *self)
{
if (!symbol_conf.col_width_list_str && !symbol_conf.field_sep &&
(!symbol_conf.dso_list ||
strlist__has_entry(symbol_conf.dso_list, self->name))) {
unsigned int slen = strlen(self->name);
if (slen > dsos__col_width)
dsos__col_width = slen;
}
self->slen_calculated = 1;
}
int event__preprocess_sample(const event_t *self, struct perf_session *session,
struct addr_location *al, symbol_filter_t filter)
{
u8 cpumode = self->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
struct thread *thread = perf_session__findnew(session, self->ip.pid);
if (thread == NULL)
return -1;
if (symbol_conf.comm_list &&
!strlist__has_entry(symbol_conf.comm_list, thread->comm))
goto out_filtered;
dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
thread__find_addr_location(thread, session, cpumode, MAP__FUNCTION,
self->ip.ip, al, filter);
dump_printf(" ...... dso: %s\n",
al->map ? al->map->dso->long_name :
al->level == 'H' ? "[hypervisor]" : "<not found>");
/*
* We have to do this here as we may have a dso with no symbol hit that
* has a name longer than the ones with symbols sampled.
*/
if (al->map && !sort_dso.elide && !al->map->dso->slen_calculated)
dso__calc_col_width(al->map->dso);
if (symbol_conf.dso_list &&
(!al->map || !al->map->dso ||
!(strlist__has_entry(symbol_conf.dso_list, al->map->dso->short_name) ||
(al->map->dso->short_name != al->map->dso->long_name &&
strlist__has_entry(symbol_conf.dso_list, al->map->dso->long_name)))))
goto out_filtered;
if (symbol_conf.sym_list && al->sym &&
!strlist__has_entry(symbol_conf.sym_list, al->sym->name))
goto out_filtered;
al->filtered = false;
return 0;
out_filtered:
al->filtered = true;
return 0;
}
int event__parse_sample(event_t *event, u64 type, struct sample_data *data)
{
u64 *array = event->sample.array;
if (type & PERF_SAMPLE_IP) {
data->ip = event->ip.ip;
array++;
}
if (type & PERF_SAMPLE_TID) {
u32 *p = (u32 *)array;
data->pid = p[0];
data->tid = p[1];
array++;
}
if (type & PERF_SAMPLE_TIME) {
data->time = *array;
array++;
}
if (type & PERF_SAMPLE_ADDR) {
data->addr = *array;
array++;
}
if (type & PERF_SAMPLE_ID) {
data->id = *array;
array++;
}
if (type & PERF_SAMPLE_STREAM_ID) {
data->stream_id = *array;
array++;
}
if (type & PERF_SAMPLE_CPU) {
u32 *p = (u32 *)array;
data->cpu = *p;
array++;
}
if (type & PERF_SAMPLE_PERIOD) {
data->period = *array;
array++;
}
if (type & PERF_SAMPLE_READ) {
pr_debug("PERF_SAMPLE_READ is unsuported for now\n");
return -1;
}
if (type & PERF_SAMPLE_CALLCHAIN) {
data->callchain = (struct ip_callchain *)array;
array += 1 + data->callchain->nr;
}
if (type & PERF_SAMPLE_RAW) {
u32 *p = (u32 *)array;
data->raw_size = *p;
p++;
data->raw_data = p;
}
return 0;
}