perf_evlist__set_maps(evlist, cpus, threads);
fdarray__init(&evlist->pollfd, 64);
evlist->workload.pid = -1;
+ evlist->backward = false;
}
struct perf_evlist *perf_evlist__new(void)
return NULL;
}
-union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
+static int perf_evlist__set_paused(struct perf_evlist *evlist, bool value)
+{
+ int i;
+
+ for (i = 0; i < evlist->nr_mmaps; i++) {
+ int fd = evlist->mmap[i].fd;
+ int err;
+
+ if (fd < 0)
+ continue;
+ err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+int perf_evlist__pause(struct perf_evlist *evlist)
+{
+ return perf_evlist__set_paused(evlist, true);
+}
+
+int perf_evlist__resume(struct perf_evlist *evlist)
+{
+ return perf_evlist__set_paused(evlist, false);
+}
+
+/* When check_messup is true, 'end' must points to a good entry */
+static union perf_event *
+perf_mmap__read(struct perf_mmap *md, bool check_messup, u64 start,
+ u64 end, u64 *prev)
{
- struct perf_mmap *md = &evlist->mmap[idx];
- u64 head;
- u64 old = md->prev;
unsigned char *data = md->base + page_size;
union perf_event *event = NULL;
+ int diff = end - start;
- /*
- * Check if event was unmapped due to a POLLHUP/POLLERR.
- */
- if (!atomic_read(&md->refcnt))
- return NULL;
-
- head = perf_mmap__read_head(md);
- if (evlist->overwrite) {
+ if (check_messup) {
/*
* 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.
+ * If we somehow ended up ahead of the 'end', we got messed up.
*
- * In either case, truncate and restart at head.
+ * In either case, truncate and restart at 'end'.
*/
- 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.
+ * 'end' points to a known good entry, start there.
*/
- old = head;
+ start = end;
+ diff = 0;
}
}
- if (old != head) {
+ if (diff >= (int)sizeof(event->header)) {
size_t size;
- event = (union perf_event *)&data[old & md->mask];
+ event = (union perf_event *)&data[start & md->mask];
size = event->header.size;
+ if (size < sizeof(event->header) || diff < (int)size) {
+ event = NULL;
+ goto broken_event;
+ }
+
/*
* 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;
+ if ((start & md->mask) + size != ((start + size) & md->mask)) {
+ unsigned int offset = start;
unsigned int len = min(sizeof(*event), size), cpy;
void *dst = md->event_copy;
event = (union perf_event *) md->event_copy;
}
- old += size;
+ start += size;
}
- md->prev = old;
+broken_event:
+ if (prev)
+ *prev = start;
return event;
}
+union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
+{
+ struct perf_mmap *md = &evlist->mmap[idx];
+ u64 head;
+ u64 old = md->prev;
+
+ /*
+ * Check if event was unmapped due to a POLLHUP/POLLERR.
+ */
+ if (!atomic_read(&md->refcnt))
+ return NULL;
+
+ head = perf_mmap__read_head(md);
+
+ return perf_mmap__read(md, evlist->overwrite, old, head, &md->prev);
+}
+
+union perf_event *
+perf_evlist__mmap_read_backward(struct perf_evlist *evlist, int idx)
+{
+ struct perf_mmap *md = &evlist->mmap[idx];
+ u64 head, end;
+ u64 start = md->prev;
+
+ /*
+ * Check if event was unmapped due to a POLLHUP/POLLERR.
+ */
+ if (!atomic_read(&md->refcnt))
+ return NULL;
+
+ head = perf_mmap__read_head(md);
+ if (!head)
+ return NULL;
+
+ /*
+ * 'head' pointer starts from 0. Kernel minus sizeof(record) form
+ * it each time when kernel writes to it, so in fact 'head' is
+ * negative. 'end' pointer is made manually by adding the size of
+ * the ring buffer to 'head' pointer, means the validate data can
+ * read is the whole ring buffer. If 'end' is positive, the ring
+ * buffer has not fully filled, so we must adjust 'end' to 0.
+ *
+ * However, since both 'head' and 'end' is unsigned, we can't
+ * simply compare 'end' against 0. Here we compare '-head' and
+ * the size of the ring buffer, where -head is the number of bytes
+ * kernel write to the ring buffer.
+ */
+ if (-head < (u64)(md->mask + 1))
+ end = 0;
+ else
+ end = head + md->mask + 1;
+
+ return perf_mmap__read(md, false, start, end, &md->prev);
+}
+
+void perf_evlist__mmap_read_catchup(struct perf_evlist *evlist, int idx)
+{
+ struct perf_mmap *md = &evlist->mmap[idx];
+ u64 head;
+
+ if (!atomic_read(&md->refcnt))
+ return;
+
+ head = perf_mmap__read_head(md);
+ md->prev = head;
+}
+
static bool perf_mmap__empty(struct perf_mmap *md)
{
return perf_mmap__read_head(md) == md->prev && !md->auxtrace_mmap.base;
if (evlist->mmap[idx].base != NULL) {
munmap(evlist->mmap[idx].base, evlist->mmap_len);
evlist->mmap[idx].base = NULL;
+ evlist->mmap[idx].fd = -1;
atomic_set(&evlist->mmap[idx].refcnt, 0);
}
auxtrace_mmap__munmap(&evlist->mmap[idx].auxtrace_mmap);
static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
{
+ int i;
+
evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
if (cpu_map__empty(evlist->cpus))
evlist->nr_mmaps = thread_map__nr(evlist->threads);
evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
+ for (i = 0; i < evlist->nr_mmaps; i++)
+ evlist->mmap[i].fd = -1;
return evlist->mmap != NULL ? 0 : -ENOMEM;
}
evlist->mmap[idx].base = NULL;
return -1;
}
+ evlist->mmap[idx].fd = fd;
if (auxtrace_mmap__mmap(&evlist->mmap[idx].auxtrace_mmap,
&mp->auxtrace_mp, evlist->mmap[idx].base, fd))
return -1;
}
-static size_t perf_evlist__mmap_size(unsigned long pages)
+unsigned long perf_event_mlock_kb_in_pages(void)
{
- if (pages == UINT_MAX) {
- int max;
+ unsigned long pages;
+ int max;
- if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
- /*
- * Pick a once upon a time good value, i.e. things look
- * strange since we can't read a sysctl value, but lets not
- * die yet...
- */
- max = 512;
- } else {
- max -= (page_size / 1024);
- }
+ if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
+ /*
+ * Pick a once upon a time good value, i.e. things look
+ * strange since we can't read a sysctl value, but lets not
+ * die yet...
+ */
+ max = 512;
+ } else {
+ max -= (page_size / 1024);
+ }
+
+ pages = (max * 1024) / page_size;
+ if (!is_power_of_2(pages))
+ pages = rounddown_pow_of_two(pages);
+
+ return pages;
+}
- pages = (max * 1024) / page_size;
- if (!is_power_of_2(pages))
- pages = rounddown_pow_of_two(pages);
- } else if (!is_power_of_2(pages))
+static size_t perf_evlist__mmap_size(unsigned long pages)
+{
+ if (pages == UINT_MAX)
+ pages = perf_event_mlock_kb_in_pages();
+ else if (!is_power_of_2(pages))
return 0;
return (pages + 1) * page_size;
perf_evlist__propagate_maps(evlist);
}
+void __perf_evlist__set_sample_bit(struct perf_evlist *evlist,
+ enum perf_event_sample_format bit)
+{
+ struct perf_evsel *evsel;
+
+ evlist__for_each(evlist, evsel)
+ __perf_evsel__set_sample_bit(evsel, bit);
+}
+
+void __perf_evlist__reset_sample_bit(struct perf_evlist *evlist,
+ enum perf_event_sample_format bit)
+{
+ struct perf_evsel *evsel;
+
+ evlist__for_each(evlist, evsel)
+ __perf_evsel__reset_sample_bit(evsel, bit);
+}
+
int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **err_evsel)
{
struct perf_evsel *evsel;
projects / cascardo / linux.git / blobdiff