kernel-ark/tools/perf/util/evlist.c
Arnaldo Carvalho de Melo a91e5431d5 perf session: Use evlist/evsel for managing perf.data attributes
So that we can reuse things like the id to attr lookup routine
(perf_evlist__id2evsel) that uses a hash table instead of the linear
lookup done in the older perf_header_attr routines, etc.

Also to make evsels/evlist more pervasive an API, simplyfing using the
emerging perf lib.

cc: Arun Sharma <arun@sharma-home.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-03-10 11:15:54 -03:00

395 lines
9.7 KiB
C

/*
* Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
*
* Parts came from builtin-{top,stat,record}.c, see those files for further
* copyright notes.
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include <poll.h>
#include "cpumap.h"
#include "thread_map.h"
#include "evlist.h"
#include "evsel.h"
#include "util.h"
#include <sys/mman.h>
#include <linux/bitops.h>
#include <linux/hash.h>
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
#define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
struct thread_map *threads)
{
int i;
for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
INIT_HLIST_HEAD(&evlist->heads[i]);
INIT_LIST_HEAD(&evlist->entries);
perf_evlist__set_maps(evlist, cpus, threads);
}
struct perf_evlist *perf_evlist__new(struct cpu_map *cpus,
struct thread_map *threads)
{
struct perf_evlist *evlist = zalloc(sizeof(*evlist));
if (evlist != NULL)
perf_evlist__init(evlist, cpus, threads);
return evlist;
}
static void perf_evlist__purge(struct perf_evlist *evlist)
{
struct perf_evsel *pos, *n;
list_for_each_entry_safe(pos, n, &evlist->entries, node) {
list_del_init(&pos->node);
perf_evsel__delete(pos);
}
evlist->nr_entries = 0;
}
void perf_evlist__exit(struct perf_evlist *evlist)
{
free(evlist->mmap);
free(evlist->pollfd);
evlist->mmap = NULL;
evlist->pollfd = NULL;
}
void perf_evlist__delete(struct perf_evlist *evlist)
{
perf_evlist__purge(evlist);
perf_evlist__exit(evlist);
free(evlist);
}
void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
{
list_add_tail(&entry->node, &evlist->entries);
++evlist->nr_entries;
}
int perf_evlist__add_default(struct perf_evlist *evlist)
{
struct perf_event_attr attr = {
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES,
};
struct perf_evsel *evsel = perf_evsel__new(&attr, 0);
if (evsel == NULL)
return -ENOMEM;
perf_evlist__add(evlist, evsel);
return 0;
}
int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
{
int nfds = evlist->cpus->nr * evlist->threads->nr * evlist->nr_entries;
evlist->pollfd = malloc(sizeof(struct pollfd) * nfds);
return evlist->pollfd != NULL ? 0 : -ENOMEM;
}
void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
{
fcntl(fd, F_SETFL, O_NONBLOCK);
evlist->pollfd[evlist->nr_fds].fd = fd;
evlist->pollfd[evlist->nr_fds].events = POLLIN;
evlist->nr_fds++;
}
static void perf_evlist__id_hash(struct perf_evlist *evlist,
struct perf_evsel *evsel,
int cpu, int thread, u64 id)
{
int hash;
struct perf_sample_id *sid = SID(evsel, cpu, 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__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
int cpu, int thread, u64 id)
{
perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
evsel->id[evsel->ids++] = id;
}
static int perf_evlist__id_add_fd(struct perf_evlist *evlist,
struct perf_evsel *evsel,
int cpu, int thread, int fd)
{
u64 read_data[4] = { 0, };
int id_idx = 1; /* The first entry is the counter value */
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;
perf_evlist__id_add(evlist, evsel, cpu, thread, read_data[id_idx]);
return 0;
}
struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id)
{
struct hlist_head *head;
struct hlist_node *pos;
struct perf_sample_id *sid;
int hash;
if (evlist->nr_entries == 1)
return list_entry(evlist->entries.next, struct perf_evsel, node);
hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
head = &evlist->heads[hash];
hlist_for_each_entry(sid, pos, head, node)
if (sid->id == id)
return sid->evsel;
return NULL;
}
union perf_event *perf_evlist__read_on_cpu(struct perf_evlist *evlist, int cpu)
{
/* XXX Move this to perf.c, making it generally available */
unsigned int page_size = sysconf(_SC_PAGE_SIZE);
struct perf_mmap *md = &evlist->mmap[cpu];
unsigned int head = perf_mmap__read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
union perf_event *event = NULL;
if (evlist->overwrite) {
/*
* If we're further behind than half the buffer, there's a chance
* the writer will bite our tail and mess up the samples under us.
*
* If we somehow ended up ahead of the head, we got messed up.
*
* In either case, truncate and restart at head.
*/
int diff = head - old;
if (diff > md->mask / 2 || diff < 0) {
fprintf(stderr, "WARNING: failed to keep up with mmap data.\n");
/*
* head points to a known good entry, start there.
*/
old = head;
}
}
if (old != head) {
size_t size;
event = (union perf_event *)&data[old & md->mask];
size = event->header.size;
/*
* Event straddles the mmap boundary -- header should always
* be inside due to u64 alignment of output.
*/
if ((old & md->mask) + size != ((old + size) & md->mask)) {
unsigned int offset = old;
unsigned int len = min(sizeof(*event), size), cpy;
void *dst = &evlist->event_copy;
do {
cpy = min(md->mask + 1 - (offset & md->mask), len);
memcpy(dst, &data[offset & md->mask], cpy);
offset += cpy;
dst += cpy;
len -= cpy;
} while (len);
event = &evlist->event_copy;
}
old += size;
}
md->prev = old;
if (!evlist->overwrite)
perf_mmap__write_tail(md, old);
return event;
}
void perf_evlist__munmap(struct perf_evlist *evlist)
{
int cpu;
for (cpu = 0; cpu < evlist->cpus->nr; cpu++) {
if (evlist->mmap[cpu].base != NULL) {
munmap(evlist->mmap[cpu].base, evlist->mmap_len);
evlist->mmap[cpu].base = NULL;
}
}
}
int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
{
evlist->mmap = zalloc(evlist->cpus->nr * sizeof(struct perf_mmap));
return evlist->mmap != NULL ? 0 : -ENOMEM;
}
static int __perf_evlist__mmap(struct perf_evlist *evlist, int cpu, int prot,
int mask, int fd)
{
evlist->mmap[cpu].prev = 0;
evlist->mmap[cpu].mask = mask;
evlist->mmap[cpu].base = mmap(NULL, evlist->mmap_len, prot,
MAP_SHARED, fd, 0);
if (evlist->mmap[cpu].base == MAP_FAILED)
return -1;
perf_evlist__add_pollfd(evlist, fd);
return 0;
}
/** perf_evlist__mmap - Create per cpu maps to receive events
*
* @evlist - list of events
* @pages - map length in pages
* @overwrite - overwrite older events?
*
* If overwrite is false the user needs to signal event consuption using:
*
* struct perf_mmap *m = &evlist->mmap[cpu];
* unsigned int head = perf_mmap__read_head(m);
*
* perf_mmap__write_tail(m, head)
*
* Using perf_evlist__read_on_cpu does this automatically.
*/
int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)
{
unsigned int page_size = sysconf(_SC_PAGE_SIZE);
int mask = pages * page_size - 1, cpu;
struct perf_evsel *first_evsel, *evsel;
const struct cpu_map *cpus = evlist->cpus;
const struct thread_map *threads = evlist->threads;
int thread, prot = PROT_READ | (overwrite ? 0 : PROT_WRITE);
if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
return -ENOMEM;
if (evlist->pollfd == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
return -ENOMEM;
evlist->overwrite = overwrite;
evlist->mmap_len = (pages + 1) * page_size;
first_evsel = list_entry(evlist->entries.next, struct perf_evsel, node);
list_for_each_entry(evsel, &evlist->entries, node) {
if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
evsel->sample_id == NULL &&
perf_evsel__alloc_id(evsel, cpus->nr, threads->nr) < 0)
return -ENOMEM;
for (cpu = 0; cpu < cpus->nr; cpu++) {
for (thread = 0; thread < threads->nr; thread++) {
int fd = FD(evsel, cpu, thread);
if (evsel->idx || thread) {
if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT,
FD(first_evsel, cpu, 0)) != 0)
goto out_unmap;
} else if (__perf_evlist__mmap(evlist, cpu, prot, mask, fd) < 0)
goto out_unmap;
if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
goto out_unmap;
}
}
}
return 0;
out_unmap:
for (cpu = 0; cpu < cpus->nr; cpu++) {
if (evlist->mmap[cpu].base != NULL) {
munmap(evlist->mmap[cpu].base, evlist->mmap_len);
evlist->mmap[cpu].base = NULL;
}
}
return -1;
}
int perf_evlist__create_maps(struct perf_evlist *evlist, pid_t target_pid,
pid_t target_tid, const char *cpu_list)
{
evlist->threads = thread_map__new(target_pid, target_tid);
if (evlist->threads == NULL)
return -1;
if (target_tid != -1)
evlist->cpus = cpu_map__dummy_new();
else
evlist->cpus = cpu_map__new(cpu_list);
if (evlist->cpus == NULL)
goto out_delete_threads;
return 0;
out_delete_threads:
thread_map__delete(evlist->threads);
return -1;
}
void perf_evlist__delete_maps(struct perf_evlist *evlist)
{
cpu_map__delete(evlist->cpus);
thread_map__delete(evlist->threads);
evlist->cpus = NULL;
evlist->threads = NULL;
}
int perf_evlist__set_filters(struct perf_evlist *evlist)
{
const struct thread_map *threads = evlist->threads;
const struct cpu_map *cpus = evlist->cpus;
struct perf_evsel *evsel;
char *filter;
int thread;
int cpu;
int err;
int fd;
list_for_each_entry(evsel, &evlist->entries, node) {
filter = evsel->filter;
if (!filter)
continue;
for (cpu = 0; cpu < cpus->nr; cpu++) {
for (thread = 0; thread < threads->nr; thread++) {
fd = FD(evsel, cpu, thread);
err = ioctl(fd, PERF_EVENT_IOC_SET_FILTER, filter);
if (err)
return err;
}
}
}
return 0;
}