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#include <poll.h>
#include "evlist.h"
#include "evsel.h"
#include "util.h"
#include <linux/bitops.h>
#include <linux/hash.h>
void perf_evlist__init(struct perf_evlist *evlist)
{
int i;
for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
INIT_HLIST_HEAD(&evlist->heads[i]);
INIT_LIST_HEAD(&evlist->entries);
}
struct perf_evlist *perf_evlist__new(void)
{
struct perf_evlist *evlist = zalloc(sizeof(*evlist));
if (evlist != NULL)
perf_evlist__init(evlist);
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 ncpus, int nthreads)
{
int nfds = ncpus * nthreads * 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++;
}
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;
}
event_t *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;
event_t *event = NULL;
int diff;
/*
* 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.
*/
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 = (event_t *)&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;
return event;
}
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