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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-23 04:34:11 +08:00
linux-next/tools/perf/util/event.c
Adrian Hunter 5b7ba82a75 perf symbols: Load kernel maps before using
In order to use kernel maps to read object code, those maps must be
adjusted to map to the dso file offset.  Because lazy-initialization is
used, that is not done until symbols are loaded.  However the maps are
first used by thread__find_addr_map() before symbols are loaded.  So
this patch changes thread__find_addr() to "load" kernel maps before
using them.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1375875537-4509-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-07 17:35:31 -03:00

744 lines
19 KiB
C

#include <linux/types.h>
#include "event.h"
#include "debug.h"
#include "machine.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
#include "thread_map.h"
static const char *perf_event__names[] = {
[0] = "TOTAL",
[PERF_RECORD_MMAP] = "MMAP",
[PERF_RECORD_LOST] = "LOST",
[PERF_RECORD_COMM] = "COMM",
[PERF_RECORD_EXIT] = "EXIT",
[PERF_RECORD_THROTTLE] = "THROTTLE",
[PERF_RECORD_UNTHROTTLE] = "UNTHROTTLE",
[PERF_RECORD_FORK] = "FORK",
[PERF_RECORD_READ] = "READ",
[PERF_RECORD_SAMPLE] = "SAMPLE",
[PERF_RECORD_HEADER_ATTR] = "ATTR",
[PERF_RECORD_HEADER_EVENT_TYPE] = "EVENT_TYPE",
[PERF_RECORD_HEADER_TRACING_DATA] = "TRACING_DATA",
[PERF_RECORD_HEADER_BUILD_ID] = "BUILD_ID",
[PERF_RECORD_FINISHED_ROUND] = "FINISHED_ROUND",
};
const char *perf_event__name(unsigned int id)
{
if (id >= ARRAY_SIZE(perf_event__names))
return "INVALID";
if (!perf_event__names[id])
return "UNKNOWN";
return perf_event__names[id];
}
static struct perf_sample synth_sample = {
.pid = -1,
.tid = -1,
.time = -1,
.stream_id = -1,
.cpu = -1,
.period = 1,
};
static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len)
{
char filename[PATH_MAX];
char bf[BUFSIZ];
FILE *fp;
size_t size = 0;
pid_t tgid = -1;
snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
fp = fopen(filename, "r");
if (fp == NULL) {
pr_debug("couldn't open %s\n", filename);
return 0;
}
while (!comm[0] || (tgid < 0)) {
if (fgets(bf, sizeof(bf), fp) == NULL) {
pr_warning("couldn't get COMM and pgid, malformed %s\n",
filename);
break;
}
if (memcmp(bf, "Name:", 5) == 0) {
char *name = bf + 5;
while (*name && isspace(*name))
++name;
size = strlen(name) - 1;
if (size >= len)
size = len - 1;
memcpy(comm, name, size);
comm[size] = '\0';
} else if (memcmp(bf, "Tgid:", 5) == 0) {
char *tgids = bf + 5;
while (*tgids && isspace(*tgids))
++tgids;
tgid = atoi(tgids);
}
}
fclose(fp);
return tgid;
}
static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
union perf_event *event, pid_t pid,
int full,
perf_event__handler_t process,
struct machine *machine)
{
char filename[PATH_MAX];
size_t size;
DIR *tasks;
struct dirent dirent, *next;
pid_t tgid;
memset(&event->comm, 0, sizeof(event->comm));
tgid = perf_event__get_comm_tgid(pid, event->comm.comm,
sizeof(event->comm.comm));
if (tgid < 0)
goto out;
event->comm.pid = tgid;
event->comm.header.type = PERF_RECORD_COMM;
size = strlen(event->comm.comm) + 1;
size = PERF_ALIGN(size, sizeof(u64));
memset(event->comm.comm + size, 0, machine->id_hdr_size);
event->comm.header.size = (sizeof(event->comm) -
(sizeof(event->comm.comm) - size) +
machine->id_hdr_size);
if (!full) {
event->comm.tid = pid;
if (process(tool, event, &synth_sample, machine) != 0)
return -1;
goto out;
}
snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
tasks = opendir(filename);
if (tasks == NULL) {
pr_debug("couldn't open %s\n", filename);
return 0;
}
while (!readdir_r(tasks, &dirent, &next) && next) {
char *end;
pid = strtol(dirent.d_name, &end, 10);
if (*end)
continue;
/* already have tgid; jut want to update the comm */
(void) perf_event__get_comm_tgid(pid, event->comm.comm,
sizeof(event->comm.comm));
size = strlen(event->comm.comm) + 1;
size = PERF_ALIGN(size, sizeof(u64));
memset(event->comm.comm + size, 0, machine->id_hdr_size);
event->comm.header.size = (sizeof(event->comm) -
(sizeof(event->comm.comm) - size) +
machine->id_hdr_size);
event->comm.tid = pid;
if (process(tool, event, &synth_sample, machine) != 0) {
tgid = -1;
break;
}
}
closedir(tasks);
out:
return tgid;
}
static int perf_event__synthesize_mmap_events(struct perf_tool *tool,
union perf_event *event,
pid_t pid, pid_t tgid,
perf_event__handler_t process,
struct machine *machine)
{
char filename[PATH_MAX];
FILE *fp;
int rc = 0;
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;
}
event->header.type = PERF_RECORD_MMAP;
/*
* Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
*/
event->header.misc = PERF_RECORD_MISC_USER;
while (1) {
char bf[BUFSIZ];
char prot[5];
char execname[PATH_MAX];
char anonstr[] = "//anon";
size_t size;
if (fgets(bf, sizeof(bf), fp) == NULL)
break;
/* ensure null termination since stack will be reused. */
strcpy(execname, "");
/* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
sscanf(bf, "%"PRIx64"-%"PRIx64" %s %"PRIx64" %*x:%*x %*u %s\n",
&event->mmap.start, &event->mmap.len, prot,
&event->mmap.pgoff, execname);
if (prot[2] != 'x')
continue;
if (!strcmp(execname, ""))
strcpy(execname, anonstr);
size = strlen(execname) + 1;
memcpy(event->mmap.filename, execname, size);
size = PERF_ALIGN(size, sizeof(u64));
event->mmap.len -= event->mmap.start;
event->mmap.header.size = (sizeof(event->mmap) -
(sizeof(event->mmap.filename) - size));
memset(event->mmap.filename + size, 0, machine->id_hdr_size);
event->mmap.header.size += machine->id_hdr_size;
event->mmap.pid = tgid;
event->mmap.tid = pid;
if (process(tool, event, &synth_sample, machine) != 0) {
rc = -1;
break;
}
}
fclose(fp);
return rc;
}
int perf_event__synthesize_modules(struct perf_tool *tool,
perf_event__handler_t process,
struct machine *machine)
{
int rc = 0;
struct rb_node *nd;
struct map_groups *kmaps = &machine->kmaps;
union perf_event *event = zalloc((sizeof(event->mmap) +
machine->id_hdr_size));
if (event == NULL) {
pr_debug("Not enough memory synthesizing mmap event "
"for kernel modules\n");
return -1;
}
event->header.type = PERF_RECORD_MMAP;
/*
* kernel uses 0 for user space maps, see kernel/perf_event.c
* __perf_event_mmap
*/
if (machine__is_host(machine))
event->header.misc = PERF_RECORD_MISC_KERNEL;
else
event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
for (nd = rb_first(&kmaps->maps[MAP__FUNCTION]);
nd; nd = rb_next(nd)) {
size_t size;
struct map *pos = rb_entry(nd, struct map, rb_node);
if (pos->dso->kernel)
continue;
size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
event->mmap.header.type = PERF_RECORD_MMAP;
event->mmap.header.size = (sizeof(event->mmap) -
(sizeof(event->mmap.filename) - size));
memset(event->mmap.filename + size, 0, machine->id_hdr_size);
event->mmap.header.size += machine->id_hdr_size;
event->mmap.start = pos->start;
event->mmap.len = pos->end - pos->start;
event->mmap.pid = machine->pid;
memcpy(event->mmap.filename, pos->dso->long_name,
pos->dso->long_name_len + 1);
if (process(tool, event, &synth_sample, machine) != 0) {
rc = -1;
break;
}
}
free(event);
return rc;
}
static int __event__synthesize_thread(union perf_event *comm_event,
union perf_event *mmap_event,
pid_t pid, int full,
perf_event__handler_t process,
struct perf_tool *tool,
struct machine *machine)
{
pid_t tgid = perf_event__synthesize_comm(tool, comm_event, pid, full,
process, machine);
if (tgid == -1)
return -1;
return perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
process, machine);
}
int perf_event__synthesize_thread_map(struct perf_tool *tool,
struct thread_map *threads,
perf_event__handler_t process,
struct machine *machine)
{
union perf_event *comm_event, *mmap_event;
int err = -1, thread, j;
comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
if (comm_event == NULL)
goto out;
mmap_event = malloc(sizeof(mmap_event->mmap) + machine->id_hdr_size);
if (mmap_event == NULL)
goto out_free_comm;
err = 0;
for (thread = 0; thread < threads->nr; ++thread) {
if (__event__synthesize_thread(comm_event, mmap_event,
threads->map[thread], 0,
process, tool, machine)) {
err = -1;
break;
}
/*
* comm.pid is set to thread group id by
* perf_event__synthesize_comm
*/
if ((int) comm_event->comm.pid != threads->map[thread]) {
bool need_leader = true;
/* is thread group leader in thread_map? */
for (j = 0; j < threads->nr; ++j) {
if ((int) comm_event->comm.pid == threads->map[j]) {
need_leader = false;
break;
}
}
/* if not, generate events for it */
if (need_leader &&
__event__synthesize_thread(comm_event,
mmap_event,
comm_event->comm.pid, 0,
process, tool, machine)) {
err = -1;
break;
}
}
}
free(mmap_event);
out_free_comm:
free(comm_event);
out:
return err;
}
int perf_event__synthesize_threads(struct perf_tool *tool,
perf_event__handler_t process,
struct machine *machine)
{
DIR *proc;
struct dirent dirent, *next;
union perf_event *comm_event, *mmap_event;
int err = -1;
comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
if (comm_event == NULL)
goto out;
mmap_event = malloc(sizeof(mmap_event->mmap) + machine->id_hdr_size);
if (mmap_event == NULL)
goto out_free_comm;
proc = opendir("/proc");
if (proc == NULL)
goto out_free_mmap;
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;
/*
* We may race with exiting thread, so don't stop just because
* one thread couldn't be synthesized.
*/
__event__synthesize_thread(comm_event, mmap_event, pid, 1,
process, tool, machine);
}
err = 0;
closedir(proc);
out_free_mmap:
free(mmap_event);
out_free_comm:
free(comm_event);
out:
return err;
}
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;
/*
* Must be a function or at least an alias, as in PARISC64, where "_text" is
* an 'A' to the same address as "_stext".
*/
if (!(symbol_type__is_a(type, MAP__FUNCTION) ||
type == 'A') || strcmp(name, args->name))
return 0;
args->start = start;
return 1;
}
int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
perf_event__handler_t process,
struct machine *machine,
const char *symbol_name)
{
size_t size;
const char *filename, *mmap_name;
char path[PATH_MAX];
char name_buff[PATH_MAX];
struct map *map;
int err;
/*
* 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, };
union perf_event *event = zalloc((sizeof(event->mmap) +
machine->id_hdr_size));
if (event == NULL) {
pr_debug("Not enough memory synthesizing mmap event "
"for kernel modules\n");
return -1;
}
mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
if (machine__is_host(machine)) {
/*
* kernel uses PERF_RECORD_MISC_USER for user space maps,
* see kernel/perf_event.c __perf_event_mmap
*/
event->header.misc = PERF_RECORD_MISC_KERNEL;
filename = "/proc/kallsyms";
} else {
event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
if (machine__is_default_guest(machine))
filename = (char *) symbol_conf.default_guest_kallsyms;
else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
filename = path;
}
}
if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0) {
free(event);
return -ENOENT;
}
map = machine->vmlinux_maps[MAP__FUNCTION];
size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
"%s%s", mmap_name, symbol_name) + 1;
size = PERF_ALIGN(size, sizeof(u64));
event->mmap.header.type = PERF_RECORD_MMAP;
event->mmap.header.size = (sizeof(event->mmap) -
(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
event->mmap.pgoff = args.start;
event->mmap.start = map->start;
event->mmap.len = map->end - event->mmap.start;
event->mmap.pid = machine->pid;
err = process(tool, event, &synth_sample, machine);
free(event);
return err;
}
size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
{
return fprintf(fp, ": %s:%d\n", event->comm.comm, event->comm.tid);
}
int perf_event__process_comm(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_comm_event(machine, event);
}
int perf_event__process_lost(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_lost_event(machine, event);
}
size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp)
{
return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %s\n",
event->mmap.pid, event->mmap.tid, event->mmap.start,
event->mmap.len, event->mmap.pgoff, event->mmap.filename);
}
int perf_event__process_mmap(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_mmap_event(machine, event);
}
size_t perf_event__fprintf_task(union perf_event *event, FILE *fp)
{
return fprintf(fp, "(%d:%d):(%d:%d)\n",
event->fork.pid, event->fork.tid,
event->fork.ppid, event->fork.ptid);
}
int perf_event__process_fork(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_fork_event(machine, event);
}
int perf_event__process_exit(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_exit_event(machine, event);
}
size_t perf_event__fprintf(union perf_event *event, FILE *fp)
{
size_t ret = fprintf(fp, "PERF_RECORD_%s",
perf_event__name(event->header.type));
switch (event->header.type) {
case PERF_RECORD_COMM:
ret += perf_event__fprintf_comm(event, fp);
break;
case PERF_RECORD_FORK:
case PERF_RECORD_EXIT:
ret += perf_event__fprintf_task(event, fp);
break;
case PERF_RECORD_MMAP:
ret += perf_event__fprintf_mmap(event, fp);
break;
default:
ret += fprintf(fp, "\n");
}
return ret;
}
int perf_event__process(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine)
{
return machine__process_event(machine, event);
}
void thread__find_addr_map(struct thread *self,
struct machine *machine, u8 cpumode,
enum map_type type, u64 addr,
struct addr_location *al, symbol_filter_t filter)
{
struct map_groups *mg = &self->mg;
bool load_map = false;
al->thread = self;
al->addr = addr;
al->cpumode = cpumode;
al->filtered = false;
if (machine == NULL) {
al->map = NULL;
return;
}
if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
al->level = 'k';
mg = &machine->kmaps;
load_map = true;
} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
al->level = '.';
} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
al->level = 'g';
mg = &machine->kmaps;
load_map = true;
} else {
/*
* 'u' means guest os user space.
* TODO: We don't support guest user space. Might support late.
*/
if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest)
al->level = 'u';
else
al->level = 'H';
al->map = NULL;
if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
!perf_guest)
al->filtered = true;
if ((cpumode == PERF_RECORD_MISC_USER ||
cpumode == PERF_RECORD_MISC_KERNEL) &&
!perf_host)
al->filtered = true;
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 &&
cpumode == PERF_RECORD_MISC_USER &&
machine && mg != &machine->kmaps) {
mg = &machine->kmaps;
goto try_again;
}
} else {
/*
* Kernel maps might be changed when loading symbols so loading
* must be done prior to using kernel maps.
*/
if (load_map)
map__load(al->map, filter);
al->addr = al->map->map_ip(al->map, al->addr);
}
}
void thread__find_addr_location(struct thread *thread, struct machine *machine,
u8 cpumode, enum map_type type, u64 addr,
struct addr_location *al,
symbol_filter_t filter)
{
thread__find_addr_map(thread, machine, cpumode, type, addr, al, filter);
if (al->map != NULL)
al->sym = map__find_symbol(al->map, al->addr, filter);
else
al->sym = NULL;
}
int perf_event__preprocess_sample(const union perf_event *event,
struct machine *machine,
struct addr_location *al,
struct perf_sample *sample,
symbol_filter_t filter)
{
u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
struct thread *thread = machine__findnew_thread(machine, event->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->tid);
/*
* Have we already created the kernel maps for this machine?
*
* This should have happened earlier, when we processed the kernel MMAP
* events, but for older perf.data files there was no such thing, so do
* it now.
*/
if (cpumode == PERF_RECORD_MISC_KERNEL &&
machine->vmlinux_maps[MAP__FUNCTION] == NULL)
machine__create_kernel_maps(machine);
thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
event->ip.ip, al, filter);
dump_printf(" ...... dso: %s\n",
al->map ? al->map->dso->long_name :
al->level == 'H' ? "[hypervisor]" : "<not found>");
al->sym = NULL;
al->cpu = sample->cpu;
if (al->map) {
struct dso *dso = al->map->dso;
if (symbol_conf.dso_list &&
(!dso || !(strlist__has_entry(symbol_conf.dso_list,
dso->short_name) ||
(dso->short_name != dso->long_name &&
strlist__has_entry(symbol_conf.dso_list,
dso->long_name)))))
goto out_filtered;
al->sym = map__find_symbol(al->map, al->addr, filter);
}
if (symbol_conf.sym_list &&
(!al->sym || !strlist__has_entry(symbol_conf.sym_list,
al->sym->name)))
goto out_filtered;
return 0;
out_filtered:
al->filtered = true;
return 0;
}