[tip:perf/core] perf top: Use perf_evsel__open

tip-bot for Arnaldo Carvalho de Melo
2011-01-26T07:16:05Z

Commit-ID: 72cb7013e08dec29631e0447f9496b7bacd3e14b
Gitweb: http://git.kernel.org/tip/72cb7013e08dec29631e0447f9496b7bacd3e14b
Author: Arnaldo Carvalho de Melo <acme@redhat.com>
AuthorDate: Wed, 12 Jan 2011 10:52:47 -0200
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Sat, 22 Jan 2011 19:56:29 -0200

perf top: Use perf_evsel__open

Now that it handles group_fd and inherit we can use it, sharing it with
stat.

Next step: 'perf record' should use, then move the mmap_array out of
->priv and into perf_evsel, with top and record sharing this, and at the
same time, write a 'perf test' stress test.

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>
---
tools/perf/builtin-top.c | 92 +++++++++++++++++++++-------------------------
1 files changed, 42 insertions(+), 50 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1bc4652..15d89be 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1210,39 +1210,50 @@ static void perf_session__mmap_read(struct perf_session *self)
}
}

-int group_fd;
-
static void start_counter(int i, struct perf_evlist *evlist,
struct perf_evsel *evsel)
{
struct xyarray *mmap_array = evsel->priv;
struct mmap_data *mm;
- struct perf_event_attr *attr;
- int cpu = -1;
int thread_index;

- if (target_tid == -1)
- cpu = cpus->map[i];
-
- attr = &evsel->attr;
+ for (thread_index = 0; thread_index < threads->nr; thread_index++) {
+ assert(FD(evsel, i, thread_index) >= 0);
+ fcntl(FD(evsel, i, thread_index), F_SETFL, O_NONBLOCK);

- attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
+ evlist->pollfd[evlist->nr_fds].fd = FD(evsel, i, thread_index);
+ evlist->pollfd[evlist->nr_fds].events = POLLIN;
+ evlist->nr_fds++;

- if (freq) {
- attr->sample_type |= PERF_SAMPLE_PERIOD;
- attr->freq = 1;
- attr->sample_freq = freq;
+ mm = xyarray__entry(mmap_array, i, thread_index);
+ mm->prev = 0;
+ mm->mask = mmap_pages*page_size - 1;
+ mm->base = mmap(NULL, (mmap_pages+1)*page_size,
+ PROT_READ, MAP_SHARED, FD(evsel, i, thread_index), 0);
+ if (mm->base == MAP_FAILED)
+ die("failed to mmap with %d (%s)\n", errno, strerror(errno));
}
+}
+
+static void start_counters(struct perf_evlist *evlist)
+{
+ struct perf_evsel *counter;
+ int i;

- attr->inherit = (cpu < 0) && inherit;
- attr->mmap = 1;
+ list_for_each_entry(counter, &evlist->entries, node) {
+ struct perf_event_attr *attr = &counter->attr;

- for (thread_index = 0; thread_index < threads->nr; thread_index++) {
-try_again:
- FD(evsel, i, thread_index) = sys_perf_event_open(attr,
- threads->map[thread_index], cpu, group_fd, 0);
+ attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
+
+ if (freq) {
+ attr->sample_type |= PERF_SAMPLE_PERIOD;
+ attr->freq = 1;
+ attr->sample_freq = freq;
+ }

- if (FD(evsel, i, thread_index) < 0) {
+ attr->mmap = 1;
+try_again:
+ if (perf_evsel__open(counter, cpus, threads, group, inherit) < 0) {
int err = errno;

if (err == EPERM || err == EACCES)
@@ -1254,8 +1265,8 @@ try_again:
* based cpu-clock-tick sw counter, which
* is always available even if no PMU support:
*/
- if (attr->type == PERF_TYPE_HARDWARE
- && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
+ if (attr->type == PERF_TYPE_HARDWARE &&
+ attr->config == PERF_COUNT_HW_CPU_CYCLES) {

if (verbose)
warning(" ... trying to fall back to cpu-clock-ticks\n");
@@ -1265,39 +1276,24 @@ try_again:
goto try_again;
}
printf("\n");
- error("sys_perf_event_open() syscall returned with %d (%s). /bin/dmesg may provide additional information.\n",
- FD(evsel, i, thread_index), strerror(err));
+ error("sys_perf_event_open() syscall returned with %d "
+ "(%s). /bin/dmesg may provide additional information.\n",
+ err, strerror(err));
die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
exit(-1);
}
- assert(FD(evsel, i, thread_index) >= 0);
- fcntl(FD(evsel, i, thread_index), F_SETFL, O_NONBLOCK);
-
- /*
- * First counter acts as the group leader:
- */
- if (group && group_fd == -1)
- group_fd = FD(evsel, i, thread_index);
-
- evlist->pollfd[evlist->nr_fds].fd = FD(evsel, i, thread_index);
- evlist->pollfd[evlist->nr_fds].events = POLLIN;
- evlist->nr_fds++;
+ }

- mm = xyarray__entry(mmap_array, i, thread_index);
- mm->prev = 0;
- mm->mask = mmap_pages*page_size - 1;
- mm->base = mmap(NULL, (mmap_pages+1)*page_size,
- PROT_READ, MAP_SHARED, FD(evsel, i, thread_index), 0);
- if (mm->base == MAP_FAILED)
- die("failed to mmap with %d (%s)\n", errno, strerror(errno));
+ for (i = 0; i < cpus->nr; i++) {
+ list_for_each_entry(counter, &evlist->entries, node)
+ start_counter(i, evsel_list, counter);
}
}

static int __cmd_top(void)
{
pthread_t thread;
- struct perf_evsel *counter;
- int i, ret;
+ int ret;
/*
* FIXME: perf_session__new should allow passing a O_MMAP, so that all this
* mmap reading, etc is encapsulated in it. Use O_WRONLY for now.
@@ -1311,11 +1307,7 @@ static int __cmd_top(void)
else
event__synthesize_threads(event__process, session);

- for (i = 0; i < cpus->nr; i++) {
- group_fd = -1;
- list_for_each_entry(counter, &evsel_list->entries, node)
- start_counter(i, evsel_list, counter);
- }
+ start_counters(evsel_list);

/* Wait for a minimal set of events before starting the snapshot */
poll(evsel_list->pollfd, evsel_list->nr_fds, 100);