linux/tools/lib/perf/evsel.c
Namhyung Kim 1337b9dcb0 perf tools: Remove special handling of system-wide evsel
For system-wide evsels, the thread map should be dummy - i.e. it has a
single entry of -1.  But the code guarantees such a thread map, so no
need to handle it specially.

No functional change intended.

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221003204647.1481128-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-10-06 08:03:53 -03:00

558 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <perf/evsel.h>
#include <perf/cpumap.h>
#include <perf/threadmap.h>
#include <linux/list.h>
#include <internal/evsel.h>
#include <linux/zalloc.h>
#include <stdlib.h>
#include <internal/xyarray.h>
#include <internal/cpumap.h>
#include <internal/mmap.h>
#include <internal/threadmap.h>
#include <internal/lib.h>
#include <linux/string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <asm/bug.h>
void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr,
int idx)
{
INIT_LIST_HEAD(&evsel->node);
evsel->attr = *attr;
evsel->idx = idx;
evsel->leader = evsel;
}
struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr)
{
struct perf_evsel *evsel = zalloc(sizeof(*evsel));
if (evsel != NULL)
perf_evsel__init(evsel, attr, 0);
return evsel;
}
void perf_evsel__delete(struct perf_evsel *evsel)
{
free(evsel);
}
#define FD(_evsel, _cpu_map_idx, _thread) \
((int *)xyarray__entry(_evsel->fd, _cpu_map_idx, _thread))
#define MMAP(_evsel, _cpu_map_idx, _thread) \
(_evsel->mmap ? ((struct perf_mmap *) xyarray__entry(_evsel->mmap, _cpu_map_idx, _thread)) \
: NULL)
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
if (evsel->fd) {
int idx, thread;
for (idx = 0; idx < ncpus; idx++) {
for (thread = 0; thread < nthreads; thread++) {
int *fd = FD(evsel, idx, thread);
if (fd)
*fd = -1;
}
}
}
return evsel->fd != NULL ? 0 : -ENOMEM;
}
static int perf_evsel__alloc_mmap(struct perf_evsel *evsel, int ncpus, int nthreads)
{
evsel->mmap = xyarray__new(ncpus, nthreads, sizeof(struct perf_mmap));
return evsel->mmap != NULL ? 0 : -ENOMEM;
}
static int
sys_perf_event_open(struct perf_event_attr *attr,
pid_t pid, struct perf_cpu cpu, int group_fd,
unsigned long flags)
{
return syscall(__NR_perf_event_open, attr, pid, cpu.cpu, group_fd, flags);
}
static int get_group_fd(struct perf_evsel *evsel, int cpu_map_idx, int thread, int *group_fd)
{
struct perf_evsel *leader = evsel->leader;
int *fd;
if (evsel == leader) {
*group_fd = -1;
return 0;
}
/*
* Leader must be already processed/open,
* if not it's a bug.
*/
if (!leader->fd)
return -ENOTCONN;
fd = FD(leader, cpu_map_idx, thread);
if (fd == NULL || *fd == -1)
return -EBADF;
*group_fd = *fd;
return 0;
}
int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus,
struct perf_thread_map *threads)
{
struct perf_cpu cpu;
int idx, thread, err = 0;
if (cpus == NULL) {
static struct perf_cpu_map *empty_cpu_map;
if (empty_cpu_map == NULL) {
empty_cpu_map = perf_cpu_map__dummy_new();
if (empty_cpu_map == NULL)
return -ENOMEM;
}
cpus = empty_cpu_map;
}
if (threads == NULL) {
static struct perf_thread_map *empty_thread_map;
if (empty_thread_map == NULL) {
empty_thread_map = perf_thread_map__new_dummy();
if (empty_thread_map == NULL)
return -ENOMEM;
}
threads = empty_thread_map;
}
if (evsel->fd == NULL &&
perf_evsel__alloc_fd(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0)
return -ENOMEM;
perf_cpu_map__for_each_cpu(cpu, idx, cpus) {
for (thread = 0; thread < threads->nr; thread++) {
int fd, group_fd, *evsel_fd;
evsel_fd = FD(evsel, idx, thread);
if (evsel_fd == NULL) {
err = -EINVAL;
goto out;
}
err = get_group_fd(evsel, idx, thread, &group_fd);
if (err < 0)
goto out;
fd = sys_perf_event_open(&evsel->attr,
threads->map[thread].pid,
cpu, group_fd, 0);
if (fd < 0) {
err = -errno;
goto out;
}
*evsel_fd = fd;
}
}
out:
if (err)
perf_evsel__close(evsel);
return err;
}
static void perf_evsel__close_fd_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
int thread;
for (thread = 0; thread < xyarray__max_y(evsel->fd); ++thread) {
int *fd = FD(evsel, cpu_map_idx, thread);
if (fd && *fd >= 0) {
close(*fd);
*fd = -1;
}
}
}
void perf_evsel__close_fd(struct perf_evsel *evsel)
{
for (int idx = 0; idx < xyarray__max_x(evsel->fd); idx++)
perf_evsel__close_fd_cpu(evsel, idx);
}
void perf_evsel__free_fd(struct perf_evsel *evsel)
{
xyarray__delete(evsel->fd);
evsel->fd = NULL;
}
void perf_evsel__close(struct perf_evsel *evsel)
{
if (evsel->fd == NULL)
return;
perf_evsel__close_fd(evsel);
perf_evsel__free_fd(evsel);
}
void perf_evsel__close_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
if (evsel->fd == NULL)
return;
perf_evsel__close_fd_cpu(evsel, cpu_map_idx);
}
void perf_evsel__munmap(struct perf_evsel *evsel)
{
int idx, thread;
if (evsel->fd == NULL || evsel->mmap == NULL)
return;
for (idx = 0; idx < xyarray__max_x(evsel->fd); idx++) {
for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
int *fd = FD(evsel, idx, thread);
if (fd == NULL || *fd < 0)
continue;
perf_mmap__munmap(MMAP(evsel, idx, thread));
}
}
xyarray__delete(evsel->mmap);
evsel->mmap = NULL;
}
int perf_evsel__mmap(struct perf_evsel *evsel, int pages)
{
int ret, idx, thread;
struct perf_mmap_param mp = {
.prot = PROT_READ | PROT_WRITE,
.mask = (pages * page_size) - 1,
};
if (evsel->fd == NULL || evsel->mmap)
return -EINVAL;
if (perf_evsel__alloc_mmap(evsel, xyarray__max_x(evsel->fd), xyarray__max_y(evsel->fd)) < 0)
return -ENOMEM;
for (idx = 0; idx < xyarray__max_x(evsel->fd); idx++) {
for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
int *fd = FD(evsel, idx, thread);
struct perf_mmap *map;
struct perf_cpu cpu = perf_cpu_map__cpu(evsel->cpus, idx);
if (fd == NULL || *fd < 0)
continue;
map = MMAP(evsel, idx, thread);
perf_mmap__init(map, NULL, false, NULL);
ret = perf_mmap__mmap(map, &mp, *fd, cpu);
if (ret) {
perf_evsel__munmap(evsel);
return ret;
}
}
}
return 0;
}
void *perf_evsel__mmap_base(struct perf_evsel *evsel, int cpu_map_idx, int thread)
{
int *fd = FD(evsel, cpu_map_idx, thread);
if (fd == NULL || *fd < 0 || MMAP(evsel, cpu_map_idx, thread) == NULL)
return NULL;
return MMAP(evsel, cpu_map_idx, thread)->base;
}
int perf_evsel__read_size(struct perf_evsel *evsel)
{
u64 read_format = evsel->attr.read_format;
int entry = sizeof(u64); /* value */
int size = 0;
int nr = 1;
if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
size += sizeof(u64);
if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
size += sizeof(u64);
if (read_format & PERF_FORMAT_ID)
entry += sizeof(u64);
if (read_format & PERF_FORMAT_LOST)
entry += sizeof(u64);
if (read_format & PERF_FORMAT_GROUP) {
nr = evsel->nr_members;
size += sizeof(u64);
}
size += entry * nr;
return size;
}
/* This only reads values for the leader */
static int perf_evsel__read_group(struct perf_evsel *evsel, int cpu_map_idx,
int thread, struct perf_counts_values *count)
{
size_t size = perf_evsel__read_size(evsel);
int *fd = FD(evsel, cpu_map_idx, thread);
u64 read_format = evsel->attr.read_format;
u64 *data;
int idx = 1;
if (fd == NULL || *fd < 0)
return -EINVAL;
data = calloc(1, size);
if (data == NULL)
return -ENOMEM;
if (readn(*fd, data, size) <= 0) {
free(data);
return -errno;
}
/*
* This reads only the leader event intentionally since we don't have
* perf counts values for sibling events.
*/
if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
count->ena = data[idx++];
if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
count->run = data[idx++];
/* value is always available */
count->val = data[idx++];
if (read_format & PERF_FORMAT_ID)
count->id = data[idx++];
if (read_format & PERF_FORMAT_LOST)
count->lost = data[idx++];
free(data);
return 0;
}
/*
* The perf read format is very flexible. It needs to set the proper
* values according to the read format.
*/
static void perf_evsel__adjust_values(struct perf_evsel *evsel, u64 *buf,
struct perf_counts_values *count)
{
u64 read_format = evsel->attr.read_format;
int n = 0;
count->val = buf[n++];
if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
count->ena = buf[n++];
if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
count->run = buf[n++];
if (read_format & PERF_FORMAT_ID)
count->id = buf[n++];
if (read_format & PERF_FORMAT_LOST)
count->lost = buf[n++];
}
int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int thread,
struct perf_counts_values *count)
{
size_t size = perf_evsel__read_size(evsel);
int *fd = FD(evsel, cpu_map_idx, thread);
u64 read_format = evsel->attr.read_format;
struct perf_counts_values buf;
memset(count, 0, sizeof(*count));
if (fd == NULL || *fd < 0)
return -EINVAL;
if (read_format & PERF_FORMAT_GROUP)
return perf_evsel__read_group(evsel, cpu_map_idx, thread, count);
if (MMAP(evsel, cpu_map_idx, thread) &&
!(read_format & (PERF_FORMAT_ID | PERF_FORMAT_LOST)) &&
!perf_mmap__read_self(MMAP(evsel, cpu_map_idx, thread), count))
return 0;
if (readn(*fd, buf.values, size) <= 0)
return -errno;
perf_evsel__adjust_values(evsel, buf.values, count);
return 0;
}
static int perf_evsel__ioctl(struct perf_evsel *evsel, int ioc, void *arg,
int cpu_map_idx, int thread)
{
int *fd = FD(evsel, cpu_map_idx, thread);
if (fd == NULL || *fd < 0)
return -1;
return ioctl(*fd, ioc, arg);
}
static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
int ioc, void *arg,
int cpu_map_idx)
{
int thread;
for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
int err = perf_evsel__ioctl(evsel, ioc, arg, cpu_map_idx, thread);
if (err)
return err;
}
return 0;
}
int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, cpu_map_idx);
}
int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread)
{
struct perf_cpu cpu __maybe_unused;
int idx;
int err;
perf_cpu_map__for_each_cpu(cpu, idx, evsel->cpus) {
err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, idx, thread);
if (err)
return err;
}
return 0;
}
int perf_evsel__enable(struct perf_evsel *evsel)
{
int i;
int err = 0;
for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, i);
return err;
}
int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, cpu_map_idx);
}
int perf_evsel__disable(struct perf_evsel *evsel)
{
int i;
int err = 0;
for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, i);
return err;
}
int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter)
{
int err = 0, i;
for (i = 0; i < perf_cpu_map__nr(evsel->cpus) && !err; i++)
err = perf_evsel__run_ioctl(evsel,
PERF_EVENT_IOC_SET_FILTER,
(void *)filter, i);
return err;
}
struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel)
{
return evsel->cpus;
}
struct perf_thread_map *perf_evsel__threads(struct perf_evsel *evsel)
{
return evsel->threads;
}
struct perf_event_attr *perf_evsel__attr(struct perf_evsel *evsel)
{
return &evsel->attr;
}
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
if (ncpus == 0 || nthreads == 0)
return 0;
evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
if (evsel->sample_id == NULL)
return -ENOMEM;
evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
if (evsel->id == NULL) {
xyarray__delete(evsel->sample_id);
evsel->sample_id = NULL;
return -ENOMEM;
}
return 0;
}
void perf_evsel__free_id(struct perf_evsel *evsel)
{
xyarray__delete(evsel->sample_id);
evsel->sample_id = NULL;
zfree(&evsel->id);
evsel->ids = 0;
}
void perf_counts_values__scale(struct perf_counts_values *count,
bool scale, __s8 *pscaled)
{
s8 scaled = 0;
if (scale) {
if (count->run == 0) {
scaled = -1;
count->val = 0;
} else if (count->run < count->ena) {
scaled = 1;
count->val = (u64)((double)count->val * count->ena / count->run);
}
}
if (pscaled)
*pscaled = scaled;
}