linux/tools/perf/util/record.c
Adrian Hunter 60b0896cc3 perf evlist: Add perf_evlist__set_tracking_event()
Add a function to change which event is used to track mmap, comm and
task events.

This is needed with Instruction Tracing because the Instruction Tracing
event must come first but cannot be used for tracking because it will be
disabled under some circumstances.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1406786474-9306-10-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-13 19:21:32 -03:00

253 lines
5.2 KiB
C

#include "evlist.h"
#include "evsel.h"
#include "cpumap.h"
#include "parse-events.h"
#include <api/fs/fs.h>
#include "util.h"
#include "cloexec.h"
typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
static int perf_do_probe_api(setup_probe_fn_t fn, int cpu, const char *str)
{
struct perf_evlist *evlist;
struct perf_evsel *evsel;
unsigned long flags = perf_event_open_cloexec_flag();
int err = -EAGAIN, fd;
static pid_t pid = -1;
evlist = perf_evlist__new();
if (!evlist)
return -ENOMEM;
if (parse_events(evlist, str))
goto out_delete;
evsel = perf_evlist__first(evlist);
while (1) {
fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
if (fd < 0) {
if (pid == -1 && errno == EACCES) {
pid = 0;
continue;
}
goto out_delete;
}
break;
}
close(fd);
fn(evsel);
fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
if (fd < 0) {
if (errno == EINVAL)
err = -EINVAL;
goto out_delete;
}
close(fd);
err = 0;
out_delete:
perf_evlist__delete(evlist);
return err;
}
static bool perf_probe_api(setup_probe_fn_t fn)
{
const char *try[] = {"cycles:u", "instructions:u", "cpu-clock:u", NULL};
struct cpu_map *cpus;
int cpu, ret, i = 0;
cpus = cpu_map__new(NULL);
if (!cpus)
return false;
cpu = cpus->map[0];
cpu_map__delete(cpus);
do {
ret = perf_do_probe_api(fn, cpu, try[i++]);
if (!ret)
return true;
} while (ret == -EAGAIN && try[i]);
return false;
}
static void perf_probe_sample_identifier(struct perf_evsel *evsel)
{
evsel->attr.sample_type |= PERF_SAMPLE_IDENTIFIER;
}
static void perf_probe_comm_exec(struct perf_evsel *evsel)
{
evsel->attr.comm_exec = 1;
}
bool perf_can_sample_identifier(void)
{
return perf_probe_api(perf_probe_sample_identifier);
}
static bool perf_can_comm_exec(void)
{
return perf_probe_api(perf_probe_comm_exec);
}
void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts)
{
struct perf_evsel *evsel;
bool use_sample_identifier = false;
bool use_comm_exec;
/*
* Set the evsel leader links before we configure attributes,
* since some might depend on this info.
*/
if (opts->group)
perf_evlist__set_leader(evlist);
if (evlist->cpus->map[0] < 0)
opts->no_inherit = true;
use_comm_exec = perf_can_comm_exec();
evlist__for_each(evlist, evsel) {
perf_evsel__config(evsel, opts);
if (evsel->tracking && use_comm_exec)
evsel->attr.comm_exec = 1;
}
if (evlist->nr_entries > 1) {
struct perf_evsel *first = perf_evlist__first(evlist);
evlist__for_each(evlist, evsel) {
if (evsel->attr.sample_type == first->attr.sample_type)
continue;
use_sample_identifier = perf_can_sample_identifier();
break;
}
evlist__for_each(evlist, evsel)
perf_evsel__set_sample_id(evsel, use_sample_identifier);
}
perf_evlist__set_id_pos(evlist);
}
static int get_max_rate(unsigned int *rate)
{
char path[PATH_MAX];
const char *procfs = procfs__mountpoint();
if (!procfs)
return -1;
snprintf(path, PATH_MAX,
"%s/sys/kernel/perf_event_max_sample_rate", procfs);
return filename__read_int(path, (int *) rate);
}
static int record_opts__config_freq(struct record_opts *opts)
{
bool user_freq = opts->user_freq != UINT_MAX;
unsigned int max_rate;
if (opts->user_interval != ULLONG_MAX)
opts->default_interval = opts->user_interval;
if (user_freq)
opts->freq = opts->user_freq;
/*
* User specified count overrides default frequency.
*/
if (opts->default_interval)
opts->freq = 0;
else if (opts->freq) {
opts->default_interval = opts->freq;
} else {
pr_err("frequency and count are zero, aborting\n");
return -1;
}
if (get_max_rate(&max_rate))
return 0;
/*
* User specified frequency is over current maximum.
*/
if (user_freq && (max_rate < opts->freq)) {
pr_err("Maximum frequency rate (%u) reached.\n"
"Please use -F freq option with lower value or consider\n"
"tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
max_rate);
return -1;
}
/*
* Default frequency is over current maximum.
*/
if (max_rate < opts->freq) {
pr_warning("Lowering default frequency rate to %u.\n"
"Please consider tweaking "
"/proc/sys/kernel/perf_event_max_sample_rate.\n",
max_rate);
opts->freq = max_rate;
}
return 0;
}
int record_opts__config(struct record_opts *opts)
{
return record_opts__config_freq(opts);
}
bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
{
struct perf_evlist *temp_evlist;
struct perf_evsel *evsel;
int err, fd, cpu;
bool ret = false;
pid_t pid = -1;
temp_evlist = perf_evlist__new();
if (!temp_evlist)
return false;
err = parse_events(temp_evlist, str);
if (err)
goto out_delete;
evsel = perf_evlist__last(temp_evlist);
if (!evlist || cpu_map__empty(evlist->cpus)) {
struct cpu_map *cpus = cpu_map__new(NULL);
cpu = cpus ? cpus->map[0] : 0;
cpu_map__delete(cpus);
} else {
cpu = evlist->cpus->map[0];
}
while (1) {
fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1,
perf_event_open_cloexec_flag());
if (fd < 0) {
if (pid == -1 && errno == EACCES) {
pid = 0;
continue;
}
goto out_delete;
}
break;
}
close(fd);
ret = true;
out_delete:
perf_evlist__delete(temp_evlist);
return ret;
}