perf test: Validate PERF_RECORD_ events and perf_sample fields

This new test will validate these new routines extracted from 'perf
record':

 - perf_evlist__config_attrs
 - perf_evlist__prepare_workload
 - perf_evlist__start_workload

In addition to several other perf_evlist methods.

It consists of starting a simple workload, setting up just one event to
monitor ("cycles") requesting that several PERF_SAMPLE_ fields be
present in all events.

It then will check that the expected PERF_RECORD_ events are produced
and will sanity check all its fields.

Some checks performed:

. PERF_SAMPLE_TIME monotonically increases.

. PERF_SAMPLE_CPU is the one requested with sched_setaffinity

. PERF_SAMPLE_TID and PERF_SAMPLE_PID matches the one we forked
  in perf_evlist__prepare_workload and that is stored in
  evlist->workload.pid

. For the events where these fields are also present in its
  pre-sample_id_all fields (e.g. event->mmap.pid), that they are what
  is expected too.

. That we get a bunch of mmaps:

  PATH/libcSUFFIX
  PATH/ldSUFFIX
  [vdso]
  PATH/sleep

Example:

  [root@emilia ~]# taskset -c 3,4 perf test -v1 perf_sample
   6: Validate PERF_RECORD_* events & perf_sample fields:
  --- start ---
  7159480799825 3 PERF_RECORD_SAMPLE
  7159480805584 3 PERF_RECORD_SAMPLE
  7159480807814 3 PERF_RECORD_SAMPLE
  7159480810430 3 PERF_RECORD_SAMPLE
  7159480861511 3 PERF_RECORD_MMAP 8086/8086: [0x7fffffffd000(0x2000) @ 0x7fffffffd000]: //anon
  7159481052516 3 PERF_RECORD_COMM: sleep:8086
  7159481070188 3 PERF_RECORD_MMAP 8086/8086: [0x400000(0x6000) @ 0]: /bin/sleep
  7159481077104 3 PERF_RECORD_MMAP 8086/8086: [0x3d06400000(0x221000) @ 0]: /lib64/ld-2.12.so
  7159481092912 3 PERF_RECORD_MMAP 8086/8086: [0x7fff1adff000(0x1000) @ 0x7fff1adff000]: [vdso]
  7159481196779 3 PERF_RECORD_MMAP 8086/8086: [0x3d06800000(0x37f000) @ 0]: /lib64/libc-2.12.so
  7160481558435 3 PERF_RECORD_EXIT(8086:8086):(8086:8086)
  ---- end ----
  Validate PERF_RECORD_* events & perf_sample fields: Ok
  [root@emilia ~]#

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-svag18v2z4idas0dyz3umjpq@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 482ad897
...@@ -841,6 +841,339 @@ static int test__parse_events(void) ...@@ -841,6 +841,339 @@ static int test__parse_events(void)
return ret; return ret;
} }
static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t **maskp,
size_t *sizep)
{
cpu_set_t *mask;
size_t size;
int i, cpu = -1, nrcpus = 1024;
realloc:
mask = CPU_ALLOC(nrcpus);
size = CPU_ALLOC_SIZE(nrcpus);
CPU_ZERO_S(size, mask);
if (sched_getaffinity(pid, size, mask) == -1) {
CPU_FREE(mask);
if (errno == EINVAL && nrcpus < (1024 << 8)) {
nrcpus = nrcpus << 2;
goto realloc;
}
perror("sched_getaffinity");
return -1;
}
for (i = 0; i < nrcpus; i++) {
if (CPU_ISSET_S(i, size, mask)) {
if (cpu == -1) {
cpu = i;
*maskp = mask;
*sizep = size;
} else
CPU_CLR_S(i, size, mask);
}
}
if (cpu == -1)
CPU_FREE(mask);
return cpu;
}
static int test__PERF_RECORD(void)
{
struct perf_record_opts opts = {
.target_pid = -1,
.target_tid = -1,
.no_delay = true,
.freq = 10,
.mmap_pages = 256,
.sample_id_all_avail = true,
};
cpu_set_t *cpu_mask = NULL;
size_t cpu_mask_size = 0;
struct perf_evlist *evlist = perf_evlist__new(NULL, NULL);
struct perf_evsel *evsel;
struct perf_sample sample;
const char *cmd = "sleep";
const char *argv[] = { cmd, "1", NULL, };
char *bname;
u64 sample_type, prev_time = 0;
bool found_cmd_mmap = false,
found_libc_mmap = false,
found_vdso_mmap = false,
found_ld_mmap = false;
int err = -1, i, wakeups = 0, sample_size;
u32 cpu;
int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
if (evlist == NULL || argv == NULL) {
pr_debug("Not enough memory to create evlist\n");
goto out;
}
/*
* We need at least one evsel in the evlist, use the default
* one: "cycles".
*/
err = perf_evlist__add_default(evlist);
if (err < 0) {
pr_debug("Not enough memory to create evsel\n");
goto out_delete_evlist;
}
/*
* Create maps of threads and cpus to monitor. In this case
* we start with all threads and cpus (-1, -1) but then in
* perf_evlist__prepare_workload we'll fill in the only thread
* we're monitoring, the one forked there.
*/
err = perf_evlist__create_maps(evlist, opts.target_pid,
opts.target_tid, opts.cpu_list);
if (err < 0) {
pr_debug("Not enough memory to create thread/cpu maps\n");
goto out_delete_evlist;
}
/*
* Prepare the workload in argv[] to run, it'll fork it, and then wait
* for perf_evlist__start_workload() to exec it. This is done this way
* so that we have time to open the evlist (calling sys_perf_event_open
* on all the fds) and then mmap them.
*/
err = perf_evlist__prepare_workload(evlist, &opts, argv);
if (err < 0) {
pr_debug("Couldn't run the workload!\n");
goto out_delete_evlist;
}
/*
* Config the evsels, setting attr->comm on the first one, etc.
*/
evsel = list_entry(evlist->entries.next, struct perf_evsel, node);
evsel->attr.sample_type |= PERF_SAMPLE_CPU;
evsel->attr.sample_type |= PERF_SAMPLE_TID;
evsel->attr.sample_type |= PERF_SAMPLE_TIME;
perf_evlist__config_attrs(evlist, &opts);
err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask,
&cpu_mask_size);
if (err < 0) {
pr_debug("sched__get_first_possible_cpu: %s\n", strerror(errno));
goto out_delete_evlist;
}
cpu = err;
/*
* So that we can check perf_sample.cpu on all the samples.
*/
if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, cpu_mask) < 0) {
pr_debug("sched_setaffinity: %s\n", strerror(errno));
goto out_free_cpu_mask;
}
/*
* Call sys_perf_event_open on all the fds on all the evsels,
* grouping them if asked to.
*/
err = perf_evlist__open(evlist, opts.group);
if (err < 0) {
pr_debug("perf_evlist__open: %s\n", strerror(errno));
goto out_delete_evlist;
}
/*
* mmap the first fd on a given CPU and ask for events for the other
* fds in the same CPU to be injected in the same mmap ring buffer
* (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
*/
err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
if (err < 0) {
pr_debug("perf_evlist__mmap: %s\n", strerror(errno));
goto out_delete_evlist;
}
/*
* We'll need these two to parse the PERF_SAMPLE_* fields in each
* event.
*/
sample_type = perf_evlist__sample_type(evlist);
sample_size = __perf_evsel__sample_size(sample_type);
/*
* Now that all is properly set up, enable the events, they will
* count just on workload.pid, which will start...
*/
perf_evlist__enable(evlist);
/*
* Now!
*/
perf_evlist__start_workload(evlist);
err = -1;
while (1) {
int before = total_events;
for (i = 0; i < evlist->nr_mmaps; i++) {
union perf_event *event;
while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
const u32 type = event->header.type;
const char *name = perf_event__name(type);
++total_events;
if (type < PERF_RECORD_MAX)
nr_events[type]++;
if (perf_event__parse_sample(event, sample_type,
sample_size, true,
&sample, false) < 0) {
if (verbose)
perf_event__fprintf(event, stderr);
pr_debug("Couldn't parse sample\n");
goto out_err;
}
if (verbose) {
pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
perf_event__fprintf(event, stderr);
}
if (prev_time > sample.time) {
pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
name, prev_time, sample.time);
goto out_err;
}
prev_time = sample.time;
if (sample.cpu != cpu) {
pr_debug("%s with unexpected cpu, expected %d, got %d\n",
name, cpu, sample.cpu);
goto out_err;
}
if ((pid_t)sample.pid != evlist->workload.pid) {
pr_debug("%s with unexpected pid, expected %d, got %d\n",
name, evlist->workload.pid, sample.pid);
goto out_err;
}
if ((pid_t)sample.tid != evlist->workload.pid) {
pr_debug("%s with unexpected tid, expected %d, got %d\n",
name, evlist->workload.pid, sample.tid);
goto out_err;
}
if ((type == PERF_RECORD_COMM ||
type == PERF_RECORD_MMAP ||
type == PERF_RECORD_FORK ||
type == PERF_RECORD_EXIT) &&
(pid_t)event->comm.pid != evlist->workload.pid) {
pr_debug("%s with unexpected pid/tid\n", name);
goto out_err;
}
if ((type == PERF_RECORD_COMM ||
type == PERF_RECORD_MMAP) &&
event->comm.pid != event->comm.tid) {
pr_debug("%s with different pid/tid!\n", name);
goto out_err;
}
switch (type) {
case PERF_RECORD_COMM:
if (strcmp(event->comm.comm, cmd)) {
pr_debug("%s with unexpected comm!\n", name);
goto out_err;
}
break;
case PERF_RECORD_EXIT:
goto found_exit;
case PERF_RECORD_MMAP:
bname = strrchr(event->mmap.filename, '/');
if (bname != NULL) {
if (!found_cmd_mmap)
found_cmd_mmap = !strcmp(bname + 1, cmd);
if (!found_libc_mmap)
found_libc_mmap = !strncmp(bname + 1, "libc", 4);
if (!found_ld_mmap)
found_ld_mmap = !strncmp(bname + 1, "ld", 2);
} else if (!found_vdso_mmap)
found_vdso_mmap = !strcmp(event->mmap.filename, "[vdso]");
break;
case PERF_RECORD_SAMPLE:
/* Just ignore samples for now */
break;
default:
pr_debug("Unexpected perf_event->header.type %d!\n",
type);
goto out_err;
}
}
}
/*
* We don't use poll here because at least at 3.1 times the
* PERF_RECORD_{!SAMPLE} events don't honour
* perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
*/
if (total_events == before && false)
poll(evlist->pollfd, evlist->nr_fds, -1);
sleep(1);
if (++wakeups > 5) {
pr_debug("No PERF_RECORD_EXIT event!\n");
goto out_err;
}
}
found_exit:
if (nr_events[PERF_RECORD_COMM] > 1) {
pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
goto out_err;
}
if (nr_events[PERF_RECORD_COMM] == 0) {
pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
goto out_err;
}
if (!found_cmd_mmap) {
pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
goto out_err;
}
if (!found_libc_mmap) {
pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
goto out_err;
}
if (!found_ld_mmap) {
pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
goto out_err;
}
if (!found_vdso_mmap) {
pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
goto out_err;
}
err = 0;
out_err:
perf_evlist__munmap(evlist);
out_free_cpu_mask:
CPU_FREE(cpu_mask);
out_delete_evlist:
perf_evlist__delete(evlist);
out:
return err;
}
static struct test { static struct test {
const char *desc; const char *desc;
int (*func)(void); int (*func)(void);
...@@ -865,6 +1198,10 @@ static struct test { ...@@ -865,6 +1198,10 @@ static struct test {
.desc = "parse events tests", .desc = "parse events tests",
.func = test__parse_events, .func = test__parse_events,
}, },
{
.desc = "Validate PERF_RECORD_* events & perf_sample fields",
.func = test__PERF_RECORD,
},
{ {
.func = NULL, .func = NULL,
}, },
......
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