linux/tools/perf/util/session.c
Stephane Eranian 444d286639 perf tools: Fix piped mode read code
In __perf_session__process_pipe_events(), there was a risk we would read
more than what a union perf_event struct can hold. this could happen in
case, perf is reading a file which contains new record types it does not
know about and which are larger than anything it knows about.

In general, perf is supposed to skip records it does not understand, but
in pipe mode, those have to be read and ignored.  The fixed size header
contains the size of the record, but that size may be larger than union
perf_event, yet it was used as the backing to the read in:

  union perf_event event;
  void *p;

  size = event->header.size;

  p = &event;
  p += sizeof(struct perf_event_header);
  if (size - sizeof(struct perf_event_header)) {
    err = readn(self->fd, p, size - sizeof(struct perf_event_header));

We fix this by allocating a buffer based on the size reported in the
header. We reuse the buffer as much as we can. We realloc in case it
becomes too small. In the  common case, the performance impact is
negligible.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1337081295-10303-3-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-22 12:59:52 -03:00

1548 lines
40 KiB
C

#define _FILE_OFFSET_BITS 64
#include <linux/kernel.h>
#include <byteswap.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include "evlist.h"
#include "evsel.h"
#include "session.h"
#include "tool.h"
#include "sort.h"
#include "util.h"
#include "cpumap.h"
static int perf_session__open(struct perf_session *self, bool force)
{
struct stat input_stat;
if (!strcmp(self->filename, "-")) {
self->fd_pipe = true;
self->fd = STDIN_FILENO;
if (perf_session__read_header(self, self->fd) < 0)
pr_err("incompatible file format (rerun with -v to learn more)");
return 0;
}
self->fd = open(self->filename, O_RDONLY);
if (self->fd < 0) {
int err = errno;
pr_err("failed to open %s: %s", self->filename, strerror(err));
if (err == ENOENT && !strcmp(self->filename, "perf.data"))
pr_err(" (try 'perf record' first)");
pr_err("\n");
return -errno;
}
if (fstat(self->fd, &input_stat) < 0)
goto out_close;
if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
pr_err("file %s not owned by current user or root\n",
self->filename);
goto out_close;
}
if (!input_stat.st_size) {
pr_info("zero-sized file (%s), nothing to do!\n",
self->filename);
goto out_close;
}
if (perf_session__read_header(self, self->fd) < 0) {
pr_err("incompatible file format (rerun with -v to learn more)");
goto out_close;
}
if (!perf_evlist__valid_sample_type(self->evlist)) {
pr_err("non matching sample_type");
goto out_close;
}
if (!perf_evlist__valid_sample_id_all(self->evlist)) {
pr_err("non matching sample_id_all");
goto out_close;
}
self->size = input_stat.st_size;
return 0;
out_close:
close(self->fd);
self->fd = -1;
return -1;
}
void perf_session__update_sample_type(struct perf_session *self)
{
self->sample_type = perf_evlist__sample_type(self->evlist);
self->sample_size = __perf_evsel__sample_size(self->sample_type);
self->sample_id_all = perf_evlist__sample_id_all(self->evlist);
self->id_hdr_size = perf_evlist__id_hdr_size(self->evlist);
self->host_machine.id_hdr_size = self->id_hdr_size;
}
int perf_session__create_kernel_maps(struct perf_session *self)
{
int ret = machine__create_kernel_maps(&self->host_machine);
if (ret >= 0)
ret = machines__create_guest_kernel_maps(&self->machines);
return ret;
}
static void perf_session__destroy_kernel_maps(struct perf_session *self)
{
machine__destroy_kernel_maps(&self->host_machine);
machines__destroy_guest_kernel_maps(&self->machines);
}
struct perf_session *perf_session__new(const char *filename, int mode,
bool force, bool repipe,
struct perf_tool *tool)
{
struct perf_session *self;
struct stat st;
size_t len;
if (!filename || !strlen(filename)) {
if (!fstat(STDIN_FILENO, &st) && S_ISFIFO(st.st_mode))
filename = "-";
else
filename = "perf.data";
}
len = strlen(filename);
self = zalloc(sizeof(*self) + len);
if (self == NULL)
goto out;
memcpy(self->filename, filename, len);
/*
* On 64bit we can mmap the data file in one go. No need for tiny mmap
* slices. On 32bit we use 32MB.
*/
#if BITS_PER_LONG == 64
self->mmap_window = ULLONG_MAX;
#else
self->mmap_window = 32 * 1024 * 1024ULL;
#endif
self->machines = RB_ROOT;
self->repipe = repipe;
INIT_LIST_HEAD(&self->ordered_samples.samples);
INIT_LIST_HEAD(&self->ordered_samples.sample_cache);
INIT_LIST_HEAD(&self->ordered_samples.to_free);
machine__init(&self->host_machine, "", HOST_KERNEL_ID);
hists__init(&self->hists);
if (mode == O_RDONLY) {
if (perf_session__open(self, force) < 0)
goto out_delete;
perf_session__update_sample_type(self);
} else if (mode == O_WRONLY) {
/*
* In O_RDONLY mode this will be performed when reading the
* kernel MMAP event, in perf_event__process_mmap().
*/
if (perf_session__create_kernel_maps(self) < 0)
goto out_delete;
}
if (tool && tool->ordering_requires_timestamps &&
tool->ordered_samples && !self->sample_id_all) {
dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
tool->ordered_samples = false;
}
out:
return self;
out_delete:
perf_session__delete(self);
return NULL;
}
static void machine__delete_dead_threads(struct machine *machine)
{
struct thread *n, *t;
list_for_each_entry_safe(t, n, &machine->dead_threads, node) {
list_del(&t->node);
thread__delete(t);
}
}
static void perf_session__delete_dead_threads(struct perf_session *session)
{
machine__delete_dead_threads(&session->host_machine);
}
static void machine__delete_threads(struct machine *self)
{
struct rb_node *nd = rb_first(&self->threads);
while (nd) {
struct thread *t = rb_entry(nd, struct thread, rb_node);
rb_erase(&t->rb_node, &self->threads);
nd = rb_next(nd);
thread__delete(t);
}
}
static void perf_session__delete_threads(struct perf_session *session)
{
machine__delete_threads(&session->host_machine);
}
void perf_session__delete(struct perf_session *self)
{
perf_session__destroy_kernel_maps(self);
perf_session__delete_dead_threads(self);
perf_session__delete_threads(self);
machine__exit(&self->host_machine);
close(self->fd);
free(self);
}
void machine__remove_thread(struct machine *self, struct thread *th)
{
self->last_match = NULL;
rb_erase(&th->rb_node, &self->threads);
/*
* We may have references to this thread, for instance in some hist_entry
* instances, so just move them to a separate list.
*/
list_add_tail(&th->node, &self->dead_threads);
}
static bool symbol__match_parent_regex(struct symbol *sym)
{
if (sym->name && !regexec(&parent_regex, sym->name, 0, NULL, 0))
return 1;
return 0;
}
static const u8 cpumodes[] = {
PERF_RECORD_MISC_USER,
PERF_RECORD_MISC_KERNEL,
PERF_RECORD_MISC_GUEST_USER,
PERF_RECORD_MISC_GUEST_KERNEL
};
#define NCPUMODES (sizeof(cpumodes)/sizeof(u8))
static void ip__resolve_ams(struct machine *self, struct thread *thread,
struct addr_map_symbol *ams,
u64 ip)
{
struct addr_location al;
size_t i;
u8 m;
memset(&al, 0, sizeof(al));
for (i = 0; i < NCPUMODES; i++) {
m = cpumodes[i];
/*
* 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_addr_location(thread, self, m, MAP__FUNCTION,
ip, &al, NULL);
if (al.sym)
goto found;
}
found:
ams->addr = ip;
ams->al_addr = al.addr;
ams->sym = al.sym;
ams->map = al.map;
}
struct branch_info *machine__resolve_bstack(struct machine *self,
struct thread *thr,
struct branch_stack *bs)
{
struct branch_info *bi;
unsigned int i;
bi = calloc(bs->nr, sizeof(struct branch_info));
if (!bi)
return NULL;
for (i = 0; i < bs->nr; i++) {
ip__resolve_ams(self, thr, &bi[i].to, bs->entries[i].to);
ip__resolve_ams(self, thr, &bi[i].from, bs->entries[i].from);
bi[i].flags = bs->entries[i].flags;
}
return bi;
}
int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
struct thread *thread,
struct ip_callchain *chain,
struct symbol **parent)
{
u8 cpumode = PERF_RECORD_MISC_USER;
unsigned int i;
int err;
callchain_cursor_reset(&evsel->hists.callchain_cursor);
for (i = 0; i < chain->nr; i++) {
u64 ip;
struct addr_location al;
if (callchain_param.order == ORDER_CALLEE)
ip = chain->ips[i];
else
ip = chain->ips[chain->nr - i - 1];
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:
break;
}
continue;
}
al.filtered = false;
thread__find_addr_location(thread, self, cpumode,
MAP__FUNCTION, ip, &al, NULL);
if (al.sym != NULL) {
if (sort__has_parent && !*parent &&
symbol__match_parent_regex(al.sym))
*parent = al.sym;
if (!symbol_conf.use_callchain)
break;
}
err = callchain_cursor_append(&evsel->hists.callchain_cursor,
ip, al.map, al.sym);
if (err)
return err;
}
return 0;
}
static int process_event_synth_tracing_data_stub(union perf_event *event __used,
struct perf_session *session __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_event_synth_attr_stub(union perf_event *event __used,
struct perf_evlist **pevlist __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_event_sample_stub(struct perf_tool *tool __used,
union perf_event *event __used,
struct perf_sample *sample __used,
struct perf_evsel *evsel __used,
struct machine *machine __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_event_stub(struct perf_tool *tool __used,
union perf_event *event __used,
struct perf_sample *sample __used,
struct machine *machine __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_finished_round_stub(struct perf_tool *tool __used,
union perf_event *event __used,
struct perf_session *perf_session __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_event_type_stub(struct perf_tool *tool __used,
union perf_event *event __used)
{
dump_printf(": unhandled!\n");
return 0;
}
static int process_finished_round(struct perf_tool *tool,
union perf_event *event,
struct perf_session *session);
static void perf_tool__fill_defaults(struct perf_tool *tool)
{
if (tool->sample == NULL)
tool->sample = process_event_sample_stub;
if (tool->mmap == NULL)
tool->mmap = process_event_stub;
if (tool->comm == NULL)
tool->comm = process_event_stub;
if (tool->fork == NULL)
tool->fork = process_event_stub;
if (tool->exit == NULL)
tool->exit = process_event_stub;
if (tool->lost == NULL)
tool->lost = perf_event__process_lost;
if (tool->read == NULL)
tool->read = process_event_sample_stub;
if (tool->throttle == NULL)
tool->throttle = process_event_stub;
if (tool->unthrottle == NULL)
tool->unthrottle = process_event_stub;
if (tool->attr == NULL)
tool->attr = process_event_synth_attr_stub;
if (tool->event_type == NULL)
tool->event_type = process_event_type_stub;
if (tool->tracing_data == NULL)
tool->tracing_data = process_event_synth_tracing_data_stub;
if (tool->build_id == NULL)
tool->build_id = process_finished_round_stub;
if (tool->finished_round == NULL) {
if (tool->ordered_samples)
tool->finished_round = process_finished_round;
else
tool->finished_round = process_finished_round_stub;
}
}
void mem_bswap_64(void *src, int byte_size)
{
u64 *m = src;
while (byte_size > 0) {
*m = bswap_64(*m);
byte_size -= sizeof(u64);
++m;
}
}
static void perf_event__all64_swap(union perf_event *event)
{
struct perf_event_header *hdr = &event->header;
mem_bswap_64(hdr + 1, event->header.size - sizeof(*hdr));
}
static void perf_event__comm_swap(union perf_event *event)
{
event->comm.pid = bswap_32(event->comm.pid);
event->comm.tid = bswap_32(event->comm.tid);
}
static void perf_event__mmap_swap(union perf_event *event)
{
event->mmap.pid = bswap_32(event->mmap.pid);
event->mmap.tid = bswap_32(event->mmap.tid);
event->mmap.start = bswap_64(event->mmap.start);
event->mmap.len = bswap_64(event->mmap.len);
event->mmap.pgoff = bswap_64(event->mmap.pgoff);
}
static void perf_event__task_swap(union perf_event *event)
{
event->fork.pid = bswap_32(event->fork.pid);
event->fork.tid = bswap_32(event->fork.tid);
event->fork.ppid = bswap_32(event->fork.ppid);
event->fork.ptid = bswap_32(event->fork.ptid);
event->fork.time = bswap_64(event->fork.time);
}
static void perf_event__read_swap(union perf_event *event)
{
event->read.pid = bswap_32(event->read.pid);
event->read.tid = bswap_32(event->read.tid);
event->read.value = bswap_64(event->read.value);
event->read.time_enabled = bswap_64(event->read.time_enabled);
event->read.time_running = bswap_64(event->read.time_running);
event->read.id = bswap_64(event->read.id);
}
static u8 revbyte(u8 b)
{
int rev = (b >> 4) | ((b & 0xf) << 4);
rev = ((rev & 0xcc) >> 2) | ((rev & 0x33) << 2);
rev = ((rev & 0xaa) >> 1) | ((rev & 0x55) << 1);
return (u8) rev;
}
/*
* XXX this is hack in attempt to carry flags bitfield
* throught endian village. ABI says:
*
* Bit-fields are allocated from right to left (least to most significant)
* on little-endian implementations and from left to right (most to least
* significant) on big-endian implementations.
*
* The above seems to be byte specific, so we need to reverse each
* byte of the bitfield. 'Internet' also says this might be implementation
* specific and we probably need proper fix and carry perf_event_attr
* bitfield flags in separate data file FEAT_ section. Thought this seems
* to work for now.
*/
static void swap_bitfield(u8 *p, unsigned len)
{
unsigned i;
for (i = 0; i < len; i++) {
*p = revbyte(*p);
p++;
}
}
/* exported for swapping attributes in file header */
void perf_event__attr_swap(struct perf_event_attr *attr)
{
attr->type = bswap_32(attr->type);
attr->size = bswap_32(attr->size);
attr->config = bswap_64(attr->config);
attr->sample_period = bswap_64(attr->sample_period);
attr->sample_type = bswap_64(attr->sample_type);
attr->read_format = bswap_64(attr->read_format);
attr->wakeup_events = bswap_32(attr->wakeup_events);
attr->bp_type = bswap_32(attr->bp_type);
attr->bp_addr = bswap_64(attr->bp_addr);
attr->bp_len = bswap_64(attr->bp_len);
swap_bitfield((u8 *) (&attr->read_format + 1), sizeof(u64));
}
static void perf_event__hdr_attr_swap(union perf_event *event)
{
size_t size;
perf_event__attr_swap(&event->attr.attr);
size = event->header.size;
size -= (void *)&event->attr.id - (void *)event;
mem_bswap_64(event->attr.id, size);
}
static void perf_event__event_type_swap(union perf_event *event)
{
event->event_type.event_type.event_id =
bswap_64(event->event_type.event_type.event_id);
}
static void perf_event__tracing_data_swap(union perf_event *event)
{
event->tracing_data.size = bswap_32(event->tracing_data.size);
}
typedef void (*perf_event__swap_op)(union perf_event *event);
static perf_event__swap_op perf_event__swap_ops[] = {
[PERF_RECORD_MMAP] = perf_event__mmap_swap,
[PERF_RECORD_COMM] = perf_event__comm_swap,
[PERF_RECORD_FORK] = perf_event__task_swap,
[PERF_RECORD_EXIT] = perf_event__task_swap,
[PERF_RECORD_LOST] = perf_event__all64_swap,
[PERF_RECORD_READ] = perf_event__read_swap,
[PERF_RECORD_SAMPLE] = perf_event__all64_swap,
[PERF_RECORD_HEADER_ATTR] = perf_event__hdr_attr_swap,
[PERF_RECORD_HEADER_EVENT_TYPE] = perf_event__event_type_swap,
[PERF_RECORD_HEADER_TRACING_DATA] = perf_event__tracing_data_swap,
[PERF_RECORD_HEADER_BUILD_ID] = NULL,
[PERF_RECORD_HEADER_MAX] = NULL,
};
struct sample_queue {
u64 timestamp;
u64 file_offset;
union perf_event *event;
struct list_head list;
};
static void perf_session_free_sample_buffers(struct perf_session *session)
{
struct ordered_samples *os = &session->ordered_samples;
while (!list_empty(&os->to_free)) {
struct sample_queue *sq;
sq = list_entry(os->to_free.next, struct sample_queue, list);
list_del(&sq->list);
free(sq);
}
}
static int perf_session_deliver_event(struct perf_session *session,
union perf_event *event,
struct perf_sample *sample,
struct perf_tool *tool,
u64 file_offset);
static void flush_sample_queue(struct perf_session *s,
struct perf_tool *tool)
{
struct ordered_samples *os = &s->ordered_samples;
struct list_head *head = &os->samples;
struct sample_queue *tmp, *iter;
struct perf_sample sample;
u64 limit = os->next_flush;
u64 last_ts = os->last_sample ? os->last_sample->timestamp : 0ULL;
unsigned idx = 0, progress_next = os->nr_samples / 16;
int ret;
if (!tool->ordered_samples || !limit)
return;
list_for_each_entry_safe(iter, tmp, head, list) {
if (iter->timestamp > limit)
break;
ret = perf_session__parse_sample(s, iter->event, &sample);
if (ret)
pr_err("Can't parse sample, err = %d\n", ret);
else
perf_session_deliver_event(s, iter->event, &sample, tool,
iter->file_offset);
os->last_flush = iter->timestamp;
list_del(&iter->list);
list_add(&iter->list, &os->sample_cache);
if (++idx >= progress_next) {
progress_next += os->nr_samples / 16;
ui_progress__update(idx, os->nr_samples,
"Processing time ordered events...");
}
}
if (list_empty(head)) {
os->last_sample = NULL;
} else if (last_ts <= limit) {
os->last_sample =
list_entry(head->prev, struct sample_queue, list);
}
os->nr_samples = 0;
}
/*
* When perf record finishes a pass on every buffers, it records this pseudo
* event.
* We record the max timestamp t found in the pass n.
* Assuming these timestamps are monotonic across cpus, we know that if
* a buffer still has events with timestamps below t, they will be all
* available and then read in the pass n + 1.
* Hence when we start to read the pass n + 2, we can safely flush every
* events with timestamps below t.
*
* ============ PASS n =================
* CPU 0 | CPU 1
* |
* cnt1 timestamps | cnt2 timestamps
* 1 | 2
* 2 | 3
* - | 4 <--- max recorded
*
* ============ PASS n + 1 ==============
* CPU 0 | CPU 1
* |
* cnt1 timestamps | cnt2 timestamps
* 3 | 5
* 4 | 6
* 5 | 7 <---- max recorded
*
* Flush every events below timestamp 4
*
* ============ PASS n + 2 ==============
* CPU 0 | CPU 1
* |
* cnt1 timestamps | cnt2 timestamps
* 6 | 8
* 7 | 9
* - | 10
*
* Flush every events below timestamp 7
* etc...
*/
static int process_finished_round(struct perf_tool *tool,
union perf_event *event __used,
struct perf_session *session)
{
flush_sample_queue(session, tool);
session->ordered_samples.next_flush = session->ordered_samples.max_timestamp;
return 0;
}
/* The queue is ordered by time */
static void __queue_event(struct sample_queue *new, struct perf_session *s)
{
struct ordered_samples *os = &s->ordered_samples;
struct sample_queue *sample = os->last_sample;
u64 timestamp = new->timestamp;
struct list_head *p;
++os->nr_samples;
os->last_sample = new;
if (!sample) {
list_add(&new->list, &os->samples);
os->max_timestamp = timestamp;
return;
}
/*
* last_sample might point to some random place in the list as it's
* the last queued event. We expect that the new event is close to
* this.
*/
if (sample->timestamp <= timestamp) {
while (sample->timestamp <= timestamp) {
p = sample->list.next;
if (p == &os->samples) {
list_add_tail(&new->list, &os->samples);
os->max_timestamp = timestamp;
return;
}
sample = list_entry(p, struct sample_queue, list);
}
list_add_tail(&new->list, &sample->list);
} else {
while (sample->timestamp > timestamp) {
p = sample->list.prev;
if (p == &os->samples) {
list_add(&new->list, &os->samples);
return;
}
sample = list_entry(p, struct sample_queue, list);
}
list_add(&new->list, &sample->list);
}
}
#define MAX_SAMPLE_BUFFER (64 * 1024 / sizeof(struct sample_queue))
static int perf_session_queue_event(struct perf_session *s, union perf_event *event,
struct perf_sample *sample, u64 file_offset)
{
struct ordered_samples *os = &s->ordered_samples;
struct list_head *sc = &os->sample_cache;
u64 timestamp = sample->time;
struct sample_queue *new;
if (!timestamp || timestamp == ~0ULL)
return -ETIME;
if (timestamp < s->ordered_samples.last_flush) {
printf("Warning: Timestamp below last timeslice flush\n");
return -EINVAL;
}
if (!list_empty(sc)) {
new = list_entry(sc->next, struct sample_queue, list);
list_del(&new->list);
} else if (os->sample_buffer) {
new = os->sample_buffer + os->sample_buffer_idx;
if (++os->sample_buffer_idx == MAX_SAMPLE_BUFFER)
os->sample_buffer = NULL;
} else {
os->sample_buffer = malloc(MAX_SAMPLE_BUFFER * sizeof(*new));
if (!os->sample_buffer)
return -ENOMEM;
list_add(&os->sample_buffer->list, &os->to_free);
os->sample_buffer_idx = 2;
new = os->sample_buffer + 1;
}
new->timestamp = timestamp;
new->file_offset = file_offset;
new->event = event;
__queue_event(new, s);
return 0;
}
static void callchain__printf(struct perf_sample *sample)
{
unsigned int i;
printf("... chain: nr:%" PRIu64 "\n", sample->callchain->nr);
for (i = 0; i < sample->callchain->nr; i++)
printf("..... %2d: %016" PRIx64 "\n",
i, sample->callchain->ips[i]);
}
static void branch_stack__printf(struct perf_sample *sample)
{
uint64_t i;
printf("... branch stack: nr:%" PRIu64 "\n", sample->branch_stack->nr);
for (i = 0; i < sample->branch_stack->nr; i++)
printf("..... %2"PRIu64": %016" PRIx64 " -> %016" PRIx64 "\n",
i, sample->branch_stack->entries[i].from,
sample->branch_stack->entries[i].to);
}
static void perf_session__print_tstamp(struct perf_session *session,
union perf_event *event,
struct perf_sample *sample)
{
if (event->header.type != PERF_RECORD_SAMPLE &&
!session->sample_id_all) {
fputs("-1 -1 ", stdout);
return;
}
if ((session->sample_type & PERF_SAMPLE_CPU))
printf("%u ", sample->cpu);
if (session->sample_type & PERF_SAMPLE_TIME)
printf("%" PRIu64 " ", sample->time);
}
static void dump_event(struct perf_session *session, union perf_event *event,
u64 file_offset, struct perf_sample *sample)
{
if (!dump_trace)
return;
printf("\n%#" PRIx64 " [%#x]: event: %d\n",
file_offset, event->header.size, event->header.type);
trace_event(event);
if (sample)
perf_session__print_tstamp(session, event, sample);
printf("%#" PRIx64 " [%#x]: PERF_RECORD_%s", file_offset,
event->header.size, perf_event__name(event->header.type));
}
static void dump_sample(struct perf_session *session, union perf_event *event,
struct perf_sample *sample)
{
if (!dump_trace)
return;
printf("(IP, %d): %d/%d: %#" PRIx64 " period: %" PRIu64 " addr: %#" PRIx64 "\n",
event->header.misc, sample->pid, sample->tid, sample->ip,
sample->period, sample->addr);
if (session->sample_type & PERF_SAMPLE_CALLCHAIN)
callchain__printf(sample);
if (session->sample_type & PERF_SAMPLE_BRANCH_STACK)
branch_stack__printf(sample);
}
static struct machine *
perf_session__find_machine_for_cpumode(struct perf_session *session,
union perf_event *event)
{
const u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
u32 pid;
if (event->header.type == PERF_RECORD_MMAP)
pid = event->mmap.pid;
else
pid = event->ip.pid;
return perf_session__find_machine(session, pid);
}
return perf_session__find_host_machine(session);
}
static int perf_session_deliver_event(struct perf_session *session,
union perf_event *event,
struct perf_sample *sample,
struct perf_tool *tool,
u64 file_offset)
{
struct perf_evsel *evsel;
struct machine *machine;
dump_event(session, event, file_offset, sample);
evsel = perf_evlist__id2evsel(session->evlist, sample->id);
if (evsel != NULL && event->header.type != PERF_RECORD_SAMPLE) {
/*
* XXX We're leaving PERF_RECORD_SAMPLE unnacounted here
* because the tools right now may apply filters, discarding
* some of the samples. For consistency, in the future we
* should have something like nr_filtered_samples and remove
* the sample->period from total_sample_period, etc, KISS for
* now tho.
*
* Also testing against NULL allows us to handle files without
* attr.sample_id_all and/or without PERF_SAMPLE_ID. In the
* future probably it'll be a good idea to restrict event
* processing via perf_session to files with both set.
*/
hists__inc_nr_events(&evsel->hists, event->header.type);
}
machine = perf_session__find_machine_for_cpumode(session, event);
switch (event->header.type) {
case PERF_RECORD_SAMPLE:
dump_sample(session, event, sample);
if (evsel == NULL) {
++session->hists.stats.nr_unknown_id;
return 0;
}
if (machine == NULL) {
++session->hists.stats.nr_unprocessable_samples;
return 0;
}
return tool->sample(tool, event, sample, evsel, machine);
case PERF_RECORD_MMAP:
return tool->mmap(tool, event, sample, machine);
case PERF_RECORD_COMM:
return tool->comm(tool, event, sample, machine);
case PERF_RECORD_FORK:
return tool->fork(tool, event, sample, machine);
case PERF_RECORD_EXIT:
return tool->exit(tool, event, sample, machine);
case PERF_RECORD_LOST:
if (tool->lost == perf_event__process_lost)
session->hists.stats.total_lost += event->lost.lost;
return tool->lost(tool, event, sample, machine);
case PERF_RECORD_READ:
return tool->read(tool, event, sample, evsel, machine);
case PERF_RECORD_THROTTLE:
return tool->throttle(tool, event, sample, machine);
case PERF_RECORD_UNTHROTTLE:
return tool->unthrottle(tool, event, sample, machine);
default:
++session->hists.stats.nr_unknown_events;
return -1;
}
}
static int perf_session__preprocess_sample(struct perf_session *session,
union perf_event *event, struct perf_sample *sample)
{
if (event->header.type != PERF_RECORD_SAMPLE ||
!(session->sample_type & PERF_SAMPLE_CALLCHAIN))
return 0;
if (!ip_callchain__valid(sample->callchain, event)) {
pr_debug("call-chain problem with event, skipping it.\n");
++session->hists.stats.nr_invalid_chains;
session->hists.stats.total_invalid_chains += sample->period;
return -EINVAL;
}
return 0;
}
static int perf_session__process_user_event(struct perf_session *session, union perf_event *event,
struct perf_tool *tool, u64 file_offset)
{
int err;
dump_event(session, event, file_offset, NULL);
/* These events are processed right away */
switch (event->header.type) {
case PERF_RECORD_HEADER_ATTR:
err = tool->attr(event, &session->evlist);
if (err == 0)
perf_session__update_sample_type(session);
return err;
case PERF_RECORD_HEADER_EVENT_TYPE:
return tool->event_type(tool, event);
case PERF_RECORD_HEADER_TRACING_DATA:
/* setup for reading amidst mmap */
lseek(session->fd, file_offset, SEEK_SET);
return tool->tracing_data(event, session);
case PERF_RECORD_HEADER_BUILD_ID:
return tool->build_id(tool, event, session);
case PERF_RECORD_FINISHED_ROUND:
return tool->finished_round(tool, event, session);
default:
return -EINVAL;
}
}
static int perf_session__process_event(struct perf_session *session,
union perf_event *event,
struct perf_tool *tool,
u64 file_offset)
{
struct perf_sample sample;
int ret;
if (session->header.needs_swap &&
perf_event__swap_ops[event->header.type])
perf_event__swap_ops[event->header.type](event);
if (event->header.type >= PERF_RECORD_HEADER_MAX)
return -EINVAL;
hists__inc_nr_events(&session->hists, event->header.type);
if (event->header.type >= PERF_RECORD_USER_TYPE_START)
return perf_session__process_user_event(session, event, tool, file_offset);
/*
* For all kernel events we get the sample data
*/
ret = perf_session__parse_sample(session, event, &sample);
if (ret)
return ret;
/* Preprocess sample records - precheck callchains */
if (perf_session__preprocess_sample(session, event, &sample))
return 0;
if (tool->ordered_samples) {
ret = perf_session_queue_event(session, event, &sample,
file_offset);
if (ret != -ETIME)
return ret;
}
return perf_session_deliver_event(session, event, &sample, tool,
file_offset);
}
void perf_event_header__bswap(struct perf_event_header *self)
{
self->type = bswap_32(self->type);
self->misc = bswap_16(self->misc);
self->size = bswap_16(self->size);
}
struct thread *perf_session__findnew(struct perf_session *session, pid_t pid)
{
return machine__findnew_thread(&session->host_machine, pid);
}
static struct thread *perf_session__register_idle_thread(struct perf_session *self)
{
struct thread *thread = perf_session__findnew(self, 0);
if (thread == NULL || thread__set_comm(thread, "swapper")) {
pr_err("problem inserting idle task.\n");
thread = NULL;
}
return thread;
}
static void perf_session__warn_about_errors(const struct perf_session *session,
const struct perf_tool *tool)
{
if (tool->lost == perf_event__process_lost &&
session->hists.stats.nr_events[PERF_RECORD_LOST] != 0) {
ui__warning("Processed %d events and lost %d chunks!\n\n"
"Check IO/CPU overload!\n\n",
session->hists.stats.nr_events[0],
session->hists.stats.nr_events[PERF_RECORD_LOST]);
}
if (session->hists.stats.nr_unknown_events != 0) {
ui__warning("Found %u unknown events!\n\n"
"Is this an older tool processing a perf.data "
"file generated by a more recent tool?\n\n"
"If that is not the case, consider "
"reporting to linux-kernel@vger.kernel.org.\n\n",
session->hists.stats.nr_unknown_events);
}
if (session->hists.stats.nr_unknown_id != 0) {
ui__warning("%u samples with id not present in the header\n",
session->hists.stats.nr_unknown_id);
}
if (session->hists.stats.nr_invalid_chains != 0) {
ui__warning("Found invalid callchains!\n\n"
"%u out of %u events were discarded for this reason.\n\n"
"Consider reporting to linux-kernel@vger.kernel.org.\n\n",
session->hists.stats.nr_invalid_chains,
session->hists.stats.nr_events[PERF_RECORD_SAMPLE]);
}
if (session->hists.stats.nr_unprocessable_samples != 0) {
ui__warning("%u unprocessable samples recorded.\n"
"Do you have a KVM guest running and not using 'perf kvm'?\n",
session->hists.stats.nr_unprocessable_samples);
}
}
#define session_done() (*(volatile int *)(&session_done))
volatile int session_done;
static int __perf_session__process_pipe_events(struct perf_session *self,
struct perf_tool *tool)
{
union perf_event *event;
uint32_t size, cur_size = 0;
void *buf = NULL;
int skip = 0;
u64 head;
int err;
void *p;
perf_tool__fill_defaults(tool);
head = 0;
cur_size = sizeof(union perf_event);
buf = malloc(cur_size);
if (!buf)
return -errno;
more:
event = buf;
err = readn(self->fd, event, sizeof(struct perf_event_header));
if (err <= 0) {
if (err == 0)
goto done;
pr_err("failed to read event header\n");
goto out_err;
}
if (self->header.needs_swap)
perf_event_header__bswap(&event->header);
size = event->header.size;
if (size == 0)
size = 8;
if (size > cur_size) {
void *new = realloc(buf, size);
if (!new) {
pr_err("failed to allocate memory to read event\n");
goto out_err;
}
buf = new;
cur_size = size;
event = buf;
}
p = event;
p += sizeof(struct perf_event_header);
if (size - sizeof(struct perf_event_header)) {
err = readn(self->fd, p, size - sizeof(struct perf_event_header));
if (err <= 0) {
if (err == 0) {
pr_err("unexpected end of event stream\n");
goto done;
}
pr_err("failed to read event data\n");
goto out_err;
}
}
if ((skip = perf_session__process_event(self, event, tool, head)) < 0) {
pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
head, event->header.size, event->header.type);
err = -EINVAL;
goto out_err;
}
head += size;
if (skip > 0)
head += skip;
if (!session_done())
goto more;
done:
err = 0;
out_err:
free(buf);
perf_session__warn_about_errors(self, tool);
perf_session_free_sample_buffers(self);
return err;
}
static union perf_event *
fetch_mmaped_event(struct perf_session *session,
u64 head, size_t mmap_size, char *buf)
{
union perf_event *event;
/*
* Ensure we have enough space remaining to read
* the size of the event in the headers.
*/
if (head + sizeof(event->header) > mmap_size)
return NULL;
event = (union perf_event *)(buf + head);
if (session->header.needs_swap)
perf_event_header__bswap(&event->header);
if (head + event->header.size > mmap_size)
return NULL;
return event;
}
int __perf_session__process_events(struct perf_session *session,
u64 data_offset, u64 data_size,
u64 file_size, struct perf_tool *tool)
{
u64 head, page_offset, file_offset, file_pos, progress_next;
int err, mmap_prot, mmap_flags, map_idx = 0;
size_t page_size, mmap_size;
char *buf, *mmaps[8];
union perf_event *event;
uint32_t size;
perf_tool__fill_defaults(tool);
page_size = sysconf(_SC_PAGESIZE);
page_offset = page_size * (data_offset / page_size);
file_offset = page_offset;
head = data_offset - page_offset;
if (data_offset + data_size < file_size)
file_size = data_offset + data_size;
progress_next = file_size / 16;
mmap_size = session->mmap_window;
if (mmap_size > file_size)
mmap_size = file_size;
memset(mmaps, 0, sizeof(mmaps));
mmap_prot = PROT_READ;
mmap_flags = MAP_SHARED;
if (session->header.needs_swap) {
mmap_prot |= PROT_WRITE;
mmap_flags = MAP_PRIVATE;
}
remap:
buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, session->fd,
file_offset);
if (buf == MAP_FAILED) {
pr_err("failed to mmap file\n");
err = -errno;
goto out_err;
}
mmaps[map_idx] = buf;
map_idx = (map_idx + 1) & (ARRAY_SIZE(mmaps) - 1);
file_pos = file_offset + head;
more:
event = fetch_mmaped_event(session, head, mmap_size, buf);
if (!event) {
if (mmaps[map_idx]) {
munmap(mmaps[map_idx], mmap_size);
mmaps[map_idx] = NULL;
}
page_offset = page_size * (head / page_size);
file_offset += page_offset;
head -= page_offset;
goto remap;
}
size = event->header.size;
if (size == 0 ||
perf_session__process_event(session, event, tool, file_pos) < 0) {
pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
file_offset + head, event->header.size,
event->header.type);
err = -EINVAL;
goto out_err;
}
head += size;
file_pos += size;
if (file_pos >= progress_next) {
progress_next += file_size / 16;
ui_progress__update(file_pos, file_size,
"Processing events...");
}
if (file_pos < file_size)
goto more;
err = 0;
/* do the final flush for ordered samples */
session->ordered_samples.next_flush = ULLONG_MAX;
flush_sample_queue(session, tool);
out_err:
perf_session__warn_about_errors(session, tool);
perf_session_free_sample_buffers(session);
return err;
}
int perf_session__process_events(struct perf_session *self,
struct perf_tool *tool)
{
int err;
if (perf_session__register_idle_thread(self) == NULL)
return -ENOMEM;
if (!self->fd_pipe)
err = __perf_session__process_events(self,
self->header.data_offset,
self->header.data_size,
self->size, tool);
else
err = __perf_session__process_pipe_events(self, tool);
return err;
}
bool perf_session__has_traces(struct perf_session *self, const char *msg)
{
if (!(self->sample_type & PERF_SAMPLE_RAW)) {
pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
return false;
}
return true;
}
int maps__set_kallsyms_ref_reloc_sym(struct map **maps,
const char *symbol_name, u64 addr)
{
char *bracket;
enum map_type i;
struct ref_reloc_sym *ref;
ref = zalloc(sizeof(struct ref_reloc_sym));
if (ref == NULL)
return -ENOMEM;
ref->name = strdup(symbol_name);
if (ref->name == NULL) {
free(ref);
return -ENOMEM;
}
bracket = strchr(ref->name, ']');
if (bracket)
*bracket = '\0';
ref->addr = addr;
for (i = 0; i < MAP__NR_TYPES; ++i) {
struct kmap *kmap = map__kmap(maps[i]);
kmap->ref_reloc_sym = ref;
}
return 0;
}
size_t perf_session__fprintf_dsos(struct perf_session *self, FILE *fp)
{
return __dsos__fprintf(&self->host_machine.kernel_dsos, fp) +
__dsos__fprintf(&self->host_machine.user_dsos, fp) +
machines__fprintf_dsos(&self->machines, fp);
}
size_t perf_session__fprintf_dsos_buildid(struct perf_session *self, FILE *fp,
bool with_hits)
{
size_t ret = machine__fprintf_dsos_buildid(&self->host_machine, fp, with_hits);
return ret + machines__fprintf_dsos_buildid(&self->machines, fp, with_hits);
}
size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp)
{
struct perf_evsel *pos;
size_t ret = fprintf(fp, "Aggregated stats:\n");
ret += hists__fprintf_nr_events(&session->hists, fp);
list_for_each_entry(pos, &session->evlist->entries, node) {
ret += fprintf(fp, "%s stats:\n", event_name(pos));
ret += hists__fprintf_nr_events(&pos->hists, fp);
}
return ret;
}
size_t perf_session__fprintf(struct perf_session *session, FILE *fp)
{
/*
* FIXME: Here we have to actually print all the machines in this
* session, not just the host...
*/
return machine__fprintf(&session->host_machine, fp);
}
void perf_session__remove_thread(struct perf_session *session,
struct thread *th)
{
/*
* FIXME: This one makes no sense, we need to remove the thread from
* the machine it belongs to, perf_session can have many machines, so
* doing it always on ->host_machine is wrong. Fix when auditing all
* the 'perf kvm' code.
*/
machine__remove_thread(&session->host_machine, th);
}
struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session,
unsigned int type)
{
struct perf_evsel *pos;
list_for_each_entry(pos, &session->evlist->entries, node) {
if (pos->attr.type == type)
return pos;
}
return NULL;
}
void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
struct machine *machine, struct perf_evsel *evsel,
int print_sym, int print_dso, int print_symoffset)
{
struct addr_location al;
struct callchain_cursor *cursor = &evsel->hists.callchain_cursor;
struct callchain_cursor_node *node;
if (perf_event__preprocess_sample(event, machine, &al, sample,
NULL) < 0) {
error("problem processing %d event, skipping it.\n",
event->header.type);
return;
}
if (symbol_conf.use_callchain && sample->callchain) {
if (machine__resolve_callchain(machine, evsel, al.thread,
sample->callchain, NULL) != 0) {
if (verbose)
error("Failed to resolve callchain. Skipping\n");
return;
}
callchain_cursor_commit(cursor);
while (1) {
node = callchain_cursor_current(cursor);
if (!node)
break;
printf("\t%16" PRIx64, node->ip);
if (print_sym) {
printf(" ");
symbol__fprintf_symname(node->sym, stdout);
}
if (print_dso) {
printf(" (");
map__fprintf_dsoname(al.map, stdout);
printf(")");
}
printf("\n");
callchain_cursor_advance(cursor);
}
} else {
printf("%16" PRIx64, sample->ip);
if (print_sym) {
printf(" ");
if (print_symoffset)
symbol__fprintf_symname_offs(al.sym, &al,
stdout);
else
symbol__fprintf_symname(al.sym, stdout);
}
if (print_dso) {
printf(" (");
map__fprintf_dsoname(al.map, stdout);
printf(")");
}
}
}
int perf_session__cpu_bitmap(struct perf_session *session,
const char *cpu_list, unsigned long *cpu_bitmap)
{
int i;
struct cpu_map *map;
for (i = 0; i < PERF_TYPE_MAX; ++i) {
struct perf_evsel *evsel;
evsel = perf_session__find_first_evtype(session, i);
if (!evsel)
continue;
if (!(evsel->attr.sample_type & PERF_SAMPLE_CPU)) {
pr_err("File does not contain CPU events. "
"Remove -c option to proceed.\n");
return -1;
}
}
map = cpu_map__new(cpu_list);
if (map == NULL) {
pr_err("Invalid cpu_list\n");
return -1;
}
for (i = 0; i < map->nr; i++) {
int cpu = map->map[i];
if (cpu >= MAX_NR_CPUS) {
pr_err("Requested CPU %d too large. "
"Consider raising MAX_NR_CPUS\n", cpu);
return -1;
}
set_bit(cpu, cpu_bitmap);
}
return 0;
}
void perf_session__fprintf_info(struct perf_session *session, FILE *fp,
bool full)
{
struct stat st;
int ret;
if (session == NULL || fp == NULL)
return;
ret = fstat(session->fd, &st);
if (ret == -1)
return;
fprintf(fp, "# ========\n");
fprintf(fp, "# captured on: %s", ctime(&st.st_ctime));
perf_header__fprintf_info(session, fp, full);
fprintf(fp, "# ========\n#\n");
}