linux/tools/perf/tests/mmap-thread-lookup.c
Jiri Olsa 20f2be1d48 libperf: Move 'page_size' global variable to libperf
We need the 'page_size' variable in libperf, so move it there.

Add a libperf_init() as a global libperf init function to obtain this
value via sysconf() at tool start.

Committer notes:

Add internal/lib.h to tools/perf/ files using 'page_size', sometimes
replacing util.h with it if that was the only reason for having util.h
included.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lore.kernel.org/lkml/20190913132355.21634-33-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-09-25 09:51:48 -03:00

239 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <inttypes.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
#include "debug.h"
#include "event.h"
#include "tests.h"
#include "machine.h"
#include "thread_map.h"
#include "map.h"
#include "symbol.h"
#include "util/synthetic-events.h"
#include "thread.h"
#include <internal/lib.h> // page_size
#define THREADS 4
static int go_away;
struct thread_data {
pthread_t pt;
pid_t tid;
void *map;
int ready[2];
};
static struct thread_data threads[THREADS];
static int thread_init(struct thread_data *td)
{
void *map;
map = mmap(NULL, page_size,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_SHARED|MAP_ANONYMOUS, -1, 0);
if (map == MAP_FAILED) {
perror("mmap failed");
return -1;
}
td->map = map;
td->tid = syscall(SYS_gettid);
pr_debug("tid = %d, map = %p\n", td->tid, map);
return 0;
}
static void *thread_fn(void *arg)
{
struct thread_data *td = arg;
ssize_t ret;
int go = 0;
if (thread_init(td))
return NULL;
/* Signal thread_create thread is initialized. */
ret = write(td->ready[1], &go, sizeof(int));
if (ret != sizeof(int)) {
pr_err("failed to notify\n");
return NULL;
}
while (!go_away) {
/* Waiting for main thread to kill us. */
usleep(100);
}
munmap(td->map, page_size);
return NULL;
}
static int thread_create(int i)
{
struct thread_data *td = &threads[i];
int err, go;
if (pipe(td->ready))
return -1;
err = pthread_create(&td->pt, NULL, thread_fn, td);
if (!err) {
/* Wait for thread initialization. */
ssize_t ret = read(td->ready[0], &go, sizeof(int));
err = ret != sizeof(int);
}
close(td->ready[0]);
close(td->ready[1]);
return err;
}
static int threads_create(void)
{
struct thread_data *td0 = &threads[0];
int i, err = 0;
go_away = 0;
/* 0 is main thread */
if (thread_init(td0))
return -1;
for (i = 1; !err && i < THREADS; i++)
err = thread_create(i);
return err;
}
static int threads_destroy(void)
{
struct thread_data *td0 = &threads[0];
int i, err = 0;
/* cleanup the main thread */
munmap(td0->map, page_size);
go_away = 1;
for (i = 1; !err && i < THREADS; i++)
err = pthread_join(threads[i].pt, NULL);
return err;
}
typedef int (*synth_cb)(struct machine *machine);
static int synth_all(struct machine *machine)
{
return perf_event__synthesize_threads(NULL,
perf_event__process,
machine, 0, 1);
}
static int synth_process(struct machine *machine)
{
struct perf_thread_map *map;
int err;
map = thread_map__new_by_pid(getpid());
err = perf_event__synthesize_thread_map(NULL, map,
perf_event__process,
machine, 0);
perf_thread_map__put(map);
return err;
}
static int mmap_events(synth_cb synth)
{
struct machine *machine;
int err, i;
/*
* The threads_create will not return before all threads
* are spawned and all created memory map.
*
* They will loop until threads_destroy is called, so we
* can safely run synthesizing function.
*/
TEST_ASSERT_VAL("failed to create threads", !threads_create());
machine = machine__new_host();
dump_trace = verbose > 1 ? 1 : 0;
err = synth(machine);
dump_trace = 0;
TEST_ASSERT_VAL("failed to destroy threads", !threads_destroy());
TEST_ASSERT_VAL("failed to synthesize maps", !err);
/*
* All data is synthesized, try to find map for each
* thread object.
*/
for (i = 0; i < THREADS; i++) {
struct thread_data *td = &threads[i];
struct addr_location al;
struct thread *thread;
thread = machine__findnew_thread(machine, getpid(), td->tid);
pr_debug("looking for map %p\n", td->map);
thread__find_map(thread, PERF_RECORD_MISC_USER,
(unsigned long) (td->map + 1), &al);
thread__put(thread);
if (!al.map) {
pr_debug("failed, couldn't find map\n");
err = -1;
break;
}
pr_debug("map %p, addr %" PRIx64 "\n", al.map, al.map->start);
}
machine__delete_threads(machine);
machine__delete(machine);
return err;
}
/*
* This test creates 'THREADS' number of threads (including
* main thread) and each thread creates memory map.
*
* When threads are created, we synthesize them with both
* (separate tests):
* perf_event__synthesize_thread_map (process based)
* perf_event__synthesize_threads (global)
*
* We test we can find all memory maps via:
* thread__find_map
*
* by using all thread objects.
*/
int test__mmap_thread_lookup(struct test *test __maybe_unused, int subtest __maybe_unused)
{
/* perf_event__synthesize_threads synthesize */
TEST_ASSERT_VAL("failed with sythesizing all",
!mmap_events(synth_all));
/* perf_event__synthesize_thread_map synthesize */
TEST_ASSERT_VAL("failed with sythesizing process",
!mmap_events(synth_process));
return 0;
}