// SPDX-License-Identifier: GPL-2.0
#include <perf/evlist.h>
#include <perf/evsel.h>
#include <linux/bitops.h>
#include <linux/list.h>
#include <linux/hash.h>
#include <sys/ioctl.h>
#include <internal/evlist.h>
#include <internal/evsel.h>
#include <internal/xyarray.h>
#include <internal/mmap.h>
#include <internal/cpumap.h>
#include <internal/threadmap.h>
#include <internal/lib.h>
#include <linux/zalloc.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <poll.h>
#include <sys/mman.h>
#include <perf/cpumap.h>
#include <perf/threadmap.h>
#include <api/fd/array.h>
#include "internal.h"
void perf_evlist__init(struct perf_evlist *evlist)
{
INIT_LIST_HEAD(&evlist->entries);
evlist->nr_entries = 0;
fdarray__init(&evlist->pollfd, 64);
perf_evlist__reset_id_hash(evlist);
}
static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
struct perf_evsel *evsel)
{
if (evsel->system_wide) {
/* System wide: set the cpu map of the evsel to all online CPUs. */
perf_cpu_map__put(evsel->cpus);
evsel->cpus = perf_cpu_map__new_online_cpus();
} else if (evlist->has_user_cpus && evsel->is_pmu_core) {
/*
* User requested CPUs on a core PMU, ensure the requested CPUs
* are valid by intersecting with those of the PMU.
*/
perf_cpu_map__put(evsel->cpus);
evsel->cpus = perf_cpu_map__intersect(evlist->user_requested_cpus, evsel->own_cpus);
} else if (!evsel->own_cpus || evlist->has_user_cpus ||
(!evsel->requires_cpu && perf_cpu_map__has_any_cpu(evlist->user_requested_cpus))) {
/*
* The PMU didn't specify a default cpu map, this isn't a core
* event and the user requested CPUs or the evlist user
* requested CPUs have the "any CPU" (aka dummy) CPU value. In
* which case use the user requested CPUs rather than the PMU
* ones.
*/
perf_cpu_map__put(evsel->cpus);
evsel->cpus = perf_cpu_map__get(evlist->user_requested_cpus);
} else if (evsel->cpus != evsel->own_cpus) {
/*
* No user requested cpu map but the PMU cpu map doesn't match
* the evsel's. Reset it back to the PMU cpu map.
*/
perf_cpu_map__put(evsel->cpus);
evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
}
if (evsel->system_wide) {
perf_thread_map__put(evsel->threads);
evsel->threads = perf_thread_map__new_dummy();
} else {
perf_thread_map__put(evsel->threads);
evsel->threads = perf_thread_map__get(evlist->threads);
}
evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus);
}
static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
evlist->needs_map_propagation = true;
perf_evlist__for_each_evsel(evlist, evsel)
__perf_evlist__propagate_maps(evlist, evsel);
}
void perf_evlist__add(struct perf_evlist *evlist,
struct perf_evsel *evsel)
{
evsel->idx = evlist->nr_entries;
list_add_tail(&evsel->node, &evlist->entries);
evlist->nr_entries += 1;
if (evlist->needs_map_propagation)
__perf_evlist__propagate_maps(evlist, evsel);
}
void perf_evlist__remove(struct perf_evlist *evlist,
struct perf_evsel *evsel)
{
list_del_init(&evsel->node);
evlist->nr_entries -= 1;
}
struct perf_evlist *perf_evlist__new(void)
{
struct perf_evlist *evlist = zalloc(sizeof(*evlist));
if (evlist != NULL)
perf_evlist__init(evlist);
return evlist;
}
struct perf_evsel *
perf_evlist__next(struct perf_evlist *evlist, struct perf_evsel *prev)
{
struct perf_evsel *next;
if (!prev) {
next = list_first_entry(&evlist->entries,
struct perf_evsel,
node);
} else {
next = list_next_entry(prev, node);
}
/* Empty list is noticed here so don't need checking on entry. */
if (&next->node == &evlist->entries)
return NULL;
return next;
}
static void perf_evlist__purge(struct perf_evlist *evlist)
{
struct perf_evsel *pos, *n;
perf_evlist__for_each_entry_safe(evlist, n, pos) {
list_del_init(&pos->node);
perf_evsel__delete(pos);
}
evlist->nr_entries = 0;
}
void perf_evlist__exit(struct perf_evlist *evlist)
{
perf_cpu_map__put(evlist->user_requested_cpus);
perf_cpu_map__put(evlist->all_cpus);
perf_thread_map__put(evlist->threads);
evlist->user_requested_cpus = NULL;
evlist->all_cpus = NULL;
evlist->threads = NULL;
fdarray__exit(&evlist->pollfd);
}
void perf_evlist__delete(struct perf_evlist *evlist)
{
if (evlist == NULL)
return;
perf_evlist__munmap(evlist);
perf_evlist__close(evlist);
perf_evlist__purge(evlist);
perf_evlist__exit(evlist);
free(evlist);
}
void perf_evlist__set_maps(struct perf_evlist *evlist,
struct perf_cpu_map *cpus,
struct perf_thread_map *threads)
{
/*
* Allow for the possibility that one or another of the maps isn't being
* changed i.e. don't put it. Note we are assuming the maps that are
* being applied are brand new and evlist is taking ownership of the
* original reference count of 1. If that is not the case it is up to
* the caller to increase the reference count.
*/
if (cpus != evlist->user_requested_cpus) {
perf_cpu_map__put(evlist->user_requested_cpus);
evlist->user_requested_cpus = perf_cpu_map__get(cpus);
}
if (threads != evlist->threads) {
perf_thread_map__put(evlist->threads);
evlist->threads = perf_thread_map__get(threads);
}
perf_evlist__propagate_maps(evlist);
}
int perf_evlist__open(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
int err;
perf_evlist__for_each_entry(evlist, evsel) {
err = perf_evsel__open(evsel, evsel->cpus, evsel->threads);
if (err < 0)
goto out_err;
}
return 0;
out_err:
perf_evlist__close(evlist);
return err;
}
void perf_evlist__close(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
perf_evlist__for_each_entry_reverse(evlist, evsel)
perf_evsel__close(evsel);
}
void perf_evlist__enable(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
perf_evlist__for_each_entry(evlist, evsel)
perf_evsel__enable(evsel);
}
void perf_evlist__disable(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
perf_evlist__for_each_entry(evlist, evsel)
perf_evsel__disable(evsel);
}
u64 perf_evlist__read_format(struct perf_evlist *evlist)
{
struct perf_evsel *first = perf_evlist__first(evlist);
return first->attr.read_format;
}
#define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
static void perf_evlist__id_hash(struct perf_evlist *evlist,
struct perf_evsel *evsel,
int cpu_map_idx, int thread, u64 id)
{
int hash;
struct perf_sample_id *sid = SID(evsel, cpu_map_idx, thread);
sid->id = id;
sid->evsel = evsel;
hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
hlist_add_head(&sid->node, &evlist->heads[hash]);
}
void perf_evlist__reset_id_hash(struct perf_evlist *evlist)
{
int i;
for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
INIT_HLIST_HEAD(&evlist->heads[i]);
}
void perf_evlist__id_add(struct perf_evlist *evlist,
struct perf_evsel *evsel,
int cpu_map_idx, int thread, u64 id)
{
if (!SID(evsel, cpu_map_idx, thread))
return;
perf_evlist__id_hash(evlist, evsel, cpu_map_idx, thread, id);
evsel->id[evsel->ids++] = id;
}
int perf_evlist__id_add_fd(struct perf_evlist *evlist,
struct perf_evsel *evsel,
int cpu_map_idx, int thread, int fd)
{
u64 read_data[4] = { 0, };
int id_idx = 1; /* The first entry is the counter value */
u64 id;
int ret;
if (!SID(evsel, cpu_map_idx, thread))
return -1;
ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);
if (!ret)
goto add;
if (errno != ENOTTY)
return -1;
/* Legacy way to get event id.. All hail to old kernels! */
/*
* This way does not work with group format read, so bail
* out in that case.
*/
if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)
return -1;
if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
read(fd, &read_data, sizeof(read_data)) == -1)
return -1;
if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
++id_idx;
if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
++id_idx;
id = read_data[id_idx];
add:
perf_evlist__id_add(evlist, evsel, cpu_map_idx, thread, id);
return 0;
}
int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
{
int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);
int nr_threads = perf_thread_map__nr(evlist->threads);
int nfds = 0;
struct perf_evsel *evsel;
perf_evlist__for_each_entry(evlist, evsel) {
if (evsel->system_wide)
nfds += nr_cpus;
else
nfds += nr_cpus * nr_threads;
}
if (fdarray__available_entries(&evlist->pollfd) < nfds &&
fdarray__grow(&evlist->pollfd, nfds) < 0)
return -ENOMEM;
return 0;
}
int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd,
void *ptr, short revent, enum fdarray_flags flags)
{
int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP, flags);
if (pos >= 0) {
evlist->pollfd.priv[pos].ptr = ptr;
fcntl(fd, F_SETFL, O_NONBLOCK);
}
return pos;
}
static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd,
void *arg __maybe_unused)
{
struct perf_mmap *map = fda->priv[fd].ptr;
if (map)
perf_mmap__put(map);
}
int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)
{
return fdarray__filter(&evlist->pollfd, revents_and_mask,
perf_evlist__munmap_filtered, NULL);
}
int perf_evlist__poll(struct perf_evlist *evlist, int timeout)
{
return fdarray__poll(&evlist->pollfd, timeout);
}
static struct perf_mmap* perf_evlist__alloc_mmap(struct perf_evlist *evlist, bool overwrite)
{
int i;
struct perf_mmap *map;
map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
if (!map)
return NULL;
for (i = 0; i < evlist->nr_mmaps; i++) {
struct perf_mmap *prev = i ? &map[i - 1] : NULL;
/*
* When the perf_mmap() call is made we grab one refcount, plus
* one extra to let perf_mmap__consume() get the last
* events after all real references (perf_mmap__get()) are
* dropped.
*
* Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
* thus does perf_mmap__get() on it.
*/
perf_mmap__init(&map[i], prev, overwrite, NULL);
}
return map;
}
static void perf_evsel__set_sid_idx(struct perf_evsel *evsel, int idx, int cpu, int thread)
{
struct perf_sample_id *sid = SID(evsel, cpu, thread);
sid->idx = idx;
sid->cpu = perf_cpu_map__cpu(evsel->cpus, cpu);
sid->tid = perf_thread_map__pid(evsel->threads, thread);
}
static struct perf_mmap*
perf_evlist__mmap_cb_get(struct perf_evlist *evlist, bool overwrite, int idx)
{
struct perf_mmap *maps;
maps = overwrite ? evlist->mmap_ovw : evlist->mmap;
if (!maps) {
maps = perf_evlist__alloc_mmap(evlist, overwrite);
if (!maps)
return NULL;
if (overwrite)
evlist->mmap_ovw = maps;
else
evlist->mmap = maps;
}
return &maps[idx];
}
#define FD(e, x, y) (*(int *) xyarray__entry(e->fd, x, y))
static int
perf_evlist__mmap_cb_mmap(struct perf_mmap *map, struct perf_mmap_param *mp,
int output, struct perf_cpu cpu)
{
return perf_mmap__mmap(map, mp, output, cpu);
}
static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_mmap *map,
bool overwrite)
{
if (overwrite)
evlist->mmap_ovw_first = map;
else
evlist->mmap_first = map;
}
static int
mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
int idx, struct perf_mmap_param *mp, int cpu_idx,
int thread, int *_output, int *_output_overwrite, int *nr_mmaps)
{
struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->all_cpus, cpu_idx);
struct perf_evsel *evsel;
int revent;
perf_evlist__for_each_entry(evlist, evsel) {
bool overwrite = evsel->attr.write_backward;
enum fdarray_flags flgs;
struct perf_mmap *map;
int *output, fd, cpu;
if (evsel->system_wide && thread)
continue;
cpu = perf_cpu_map__idx(evsel->cpus, evlist_cpu);
if (cpu == -1)
continue;
map = ops->get(evlist, overwrite, idx);
if (map == NULL)
return -ENOMEM;
if (overwrite) {
mp->prot = PROT_READ;
output = _output_overwrite;
} else {
mp->prot = PROT_READ | PROT_WRITE;
output = _output;
}
fd = FD(evsel, cpu, thread);
if (*output == -1) {
*output = fd;
/*
* The last one will be done at perf_mmap__consume(), so that we
* make sure we don't prevent tools from consuming every last event in
* the ring buffer.
*
* I.e. we can get the POLLHUP meaning that the fd doesn't exist
* anymore, but the last events for it are still in the ring buffer,
* waiting to be consumed.
*
* Tools can chose to ignore this at their own discretion, but the
* evlist layer can't just drop it when filtering events in
* perf_evlist__filter_pollfd().
*/
refcount_set(&map->refcnt, 2);
if (ops->idx)
ops->idx(evlist, evsel, mp, idx);
/* Debug message used by test scripts */
pr_debug("idx %d: mmapping fd %d\n", idx, *output);
if (ops->mmap(map, mp, *output, evlist_cpu) < 0)
return -1;
*nr_mmaps += 1;
if (!idx)
perf_evlist__set_mmap_first(evlist, map, overwrite);
} else {
/* Debug message used by test scripts */
pr_debug("idx %d: set output fd %d -> %d\n", idx, fd, *output);
if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
return -1;
perf_mmap__get(map);
}
revent = !overwrite ? POLLIN : 0;
flgs = evsel->system_wide ? fdarray_flag__nonfilterable : fdarray_flag__default;
if (perf_evlist__add_pollfd(evlist, fd, map, revent, flgs) < 0) {
perf_mmap__put(map);
return -1;
}
if (evsel->attr.read_format & PERF_FORMAT_ID) {
if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,
fd) < 0)
return -1;
perf_evsel__set_sid_idx(evsel, idx, cpu, thread);
}
}
return 0;
}
static int
mmap_per_thread(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
struct perf_mmap_param *mp)
{
int nr_threads = perf_thread_map__nr(evlist->threads);
int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);
int cpu, thread, idx = 0;
int nr_mmaps = 0;
pr_debug("%s: nr cpu values (may include -1) %d nr threads %d\n",
__func__, nr_cpus, nr_threads);
/* per-thread mmaps */
for (thread = 0; thread < nr_threads; thread++, idx++) {
int output = -1;
int output_overwrite = -1;
if (mmap_per_evsel(evlist, ops, idx, mp, 0, thread, &output,
&output_overwrite, &nr_mmaps))
goto out_unmap;
}
/* system-wide mmaps i.e. per-cpu */
for (cpu = 1; cpu < nr_cpus; cpu++, idx++) {
int output = -1;
int output_overwrite = -1;
if (mmap_per_evsel(evlist, ops, idx, mp, cpu, 0, &output,
&output_overwrite, &nr_mmaps))
goto out_unmap;
}
if (nr_mmaps != evlist->nr_mmaps)
pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);
return 0;
out_unmap:
perf_evlist__munmap(evlist);
return -1;
}
static int
mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
struct perf_mmap_param *mp)
{
int nr_threads = perf_thread_map__nr(evlist->threads);
int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);
int nr_mmaps = 0;
int cpu, thread;
pr_debug("%s: nr cpu values %d nr threads %d\n", __func__, nr_cpus, nr_threads);
for (cpu = 0; cpu < nr_cpus; cpu++) {
int output = -1;
int output_overwrite = -1;
for (thread = 0; thread < nr_threads; thread++) {
if (mmap_per_evsel(evlist, ops, cpu, mp, cpu,
thread, &output, &output_overwrite, &nr_mmaps))
goto out_unmap;
}
}
if (nr_mmaps != evlist->nr_mmaps)
pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);
return 0;
out_unmap:
perf_evlist__munmap(evlist);
return -1;
}
static int perf_evlist__nr_mmaps(struct perf_evlist *evlist)
{
int nr_mmaps;
/* One for each CPU */
nr_mmaps = perf_cpu_map__nr(evlist->all_cpus);
if (perf_cpu_map__has_any_cpu_or_is_empty(evlist->all_cpus)) {
/* Plus one for each thread */
nr_mmaps += perf_thread_map__nr(evlist->threads);
/* Minus the per-thread CPU (-1) */
nr_mmaps -= 1;
}
return nr_mmaps;
}
int perf_evlist__mmap_ops(struct perf_evlist *evlist,
struct perf_evlist_mmap_ops *ops,
struct perf_mmap_param *mp)
{
const struct perf_cpu_map *cpus = evlist->all_cpus;
struct perf_evsel *evsel;
if (!ops || !ops->get || !ops->mmap)
return -EINVAL;
mp->mask = evlist->mmap_len - page_size - 1;
evlist->nr_mmaps = perf_evlist__nr_mmaps(evlist);
perf_evlist__for_each_entry(evlist, evsel) {
if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
evsel->sample_id == NULL &&
perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0)
return -ENOMEM;
}
if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
return -ENOMEM;
if (perf_cpu_map__has_any_cpu_or_is_empty(cpus))
return mmap_per_thread(evlist, ops, mp);
return mmap_per_cpu(evlist, ops, mp);
}
int perf_evlist__mmap(struct perf_evlist *evlist, int pages)
{
struct perf_mmap_param mp;
struct perf_evlist_mmap_ops ops = {
.get = perf_evlist__mmap_cb_get,
.mmap = perf_evlist__mmap_cb_mmap,
};
evlist->mmap_len = (pages + 1) * page_size;
return perf_evlist__mmap_ops(evlist, &ops, &mp);
}
void perf_evlist__munmap(struct perf_evlist *evlist)
{
int i;
if (evlist->mmap) {
for (i = 0; i < evlist->nr_mmaps; i++)
perf_mmap__munmap(&evlist->mmap[i]);
}
if (evlist->mmap_ovw) {
for (i = 0; i < evlist->nr_mmaps; i++)
perf_mmap__munmap(&evlist->mmap_ovw[i]);
}
zfree(&evlist->mmap);
zfree(&evlist->mmap_ovw);
}
struct perf_mmap*
perf_evlist__next_mmap(struct perf_evlist *evlist, struct perf_mmap *map,
bool overwrite)
{
if (map)
return map->next;
return overwrite ? evlist->mmap_ovw_first : evlist->mmap_first;
}
void __perf_evlist__set_leader(struct list_head *list, struct perf_evsel *leader)
{
struct perf_evsel *evsel;
int n = 0;
__perf_evlist__for_each_entry(list, evsel) {
evsel->leader = leader;
n++;
}
leader->nr_members = n;
}
void perf_evlist__set_leader(struct perf_evlist *evlist)
{
if (evlist->nr_entries) {
struct perf_evsel *first = list_entry(evlist->entries.next,
struct perf_evsel, node);
__perf_evlist__set_leader(&evlist->entries, first);
}
}
int perf_evlist__nr_groups(struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
int nr_groups = 0;
perf_evlist__for_each_evsel(evlist, evsel) {
/*
* evsels by default have a nr_members of 1, and they are their
* own leader. If the nr_members is >1 then this is an
* indication of a group.
*/
if (evsel->leader == evsel && evsel->nr_members > 1)
nr_groups++;
}
return nr_groups;
}
void perf_evlist__go_system_wide(struct perf_evlist *evlist, struct perf_evsel *evsel)
{
if (!evsel->system_wide) {
evsel->system_wide = true;
if (evlist->needs_map_propagation)
__perf_evlist__propagate_maps(evlist, evsel);
}
}
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