https://github.com/torvalds/linux
Tip revision: bfeffd155283772bbe78c6a05dec7c0128ee500c authored by Linus Torvalds on 07 January 2019, 01:08:20 UTC
Linux 5.0-rc1
Linux 5.0-rc1
Tip revision: bfeffd1
attr.c
// SPDX-License-Identifier: GPL-2.0
/*
* The struct perf_event_attr test support.
*
* This test is embedded inside into perf directly and is governed
* by the PERF_TEST_ATTR environment variable and hook inside
* sys_perf_event_open function.
*
* The general idea is to store 'struct perf_event_attr' details for
* each event created within single perf command. Each event details
* are stored into separate text file. Once perf command is finished
* these files can be checked for values we expect for command.
*
* Besides 'struct perf_event_attr' values we also store 'fd' and
* 'group_fd' values to allow checking for groups created.
*
* This all is triggered by setting PERF_TEST_ATTR environment variable.
* It must contain name of existing directory with access and write
* permissions. All the event text files are stored there.
*/
#include <debug.h>
#include <errno.h>
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "../perf.h"
#include <subcmd/exec-cmd.h>
#include "tests.h"
#define ENV "PERF_TEST_ATTR"
static char *dir;
static bool ready;
void test_attr__init(void)
{
dir = getenv(ENV);
test_attr__enabled = (dir != NULL);
}
#define BUFSIZE 1024
#define __WRITE_ASS(str, fmt, data) \
do { \
char buf[BUFSIZE]; \
size_t size; \
\
size = snprintf(buf, BUFSIZE, #str "=%"fmt "\n", data); \
if (1 != fwrite(buf, size, 1, file)) { \
perror("test attr - failed to write event file"); \
fclose(file); \
return -1; \
} \
\
} while (0)
#define WRITE_ASS(field, fmt) __WRITE_ASS(field, fmt, attr->field)
static int store_event(struct perf_event_attr *attr, pid_t pid, int cpu,
int fd, int group_fd, unsigned long flags)
{
FILE *file;
char path[PATH_MAX];
if (!ready)
return 0;
snprintf(path, PATH_MAX, "%s/event-%d-%llu-%d", dir,
attr->type, attr->config, fd);
file = fopen(path, "w+");
if (!file) {
perror("test attr - failed to open event file");
return -1;
}
if (fprintf(file, "[event-%d-%llu-%d]\n",
attr->type, attr->config, fd) < 0) {
perror("test attr - failed to write event file");
fclose(file);
return -1;
}
/* syscall arguments */
__WRITE_ASS(fd, "d", fd);
__WRITE_ASS(group_fd, "d", group_fd);
__WRITE_ASS(cpu, "d", cpu);
__WRITE_ASS(pid, "d", pid);
__WRITE_ASS(flags, "lu", flags);
/* struct perf_event_attr */
WRITE_ASS(type, PRIu32);
WRITE_ASS(size, PRIu32);
WRITE_ASS(config, "llu");
WRITE_ASS(sample_period, "llu");
WRITE_ASS(sample_type, "llu");
WRITE_ASS(read_format, "llu");
WRITE_ASS(disabled, "d");
WRITE_ASS(inherit, "d");
WRITE_ASS(pinned, "d");
WRITE_ASS(exclusive, "d");
WRITE_ASS(exclude_user, "d");
WRITE_ASS(exclude_kernel, "d");
WRITE_ASS(exclude_hv, "d");
WRITE_ASS(exclude_idle, "d");
WRITE_ASS(mmap, "d");
WRITE_ASS(comm, "d");
WRITE_ASS(freq, "d");
WRITE_ASS(inherit_stat, "d");
WRITE_ASS(enable_on_exec, "d");
WRITE_ASS(task, "d");
WRITE_ASS(watermark, "d");
WRITE_ASS(precise_ip, "d");
WRITE_ASS(mmap_data, "d");
WRITE_ASS(sample_id_all, "d");
WRITE_ASS(exclude_host, "d");
WRITE_ASS(exclude_guest, "d");
WRITE_ASS(exclude_callchain_kernel, "d");
WRITE_ASS(exclude_callchain_user, "d");
WRITE_ASS(mmap2, "d");
WRITE_ASS(comm_exec, "d");
WRITE_ASS(context_switch, "d");
WRITE_ASS(write_backward, "d");
WRITE_ASS(namespaces, "d");
WRITE_ASS(use_clockid, "d");
WRITE_ASS(wakeup_events, PRIu32);
WRITE_ASS(bp_type, PRIu32);
WRITE_ASS(config1, "llu");
WRITE_ASS(config2, "llu");
WRITE_ASS(branch_sample_type, "llu");
WRITE_ASS(sample_regs_user, "llu");
WRITE_ASS(sample_stack_user, PRIu32);
fclose(file);
return 0;
}
void test_attr__open(struct perf_event_attr *attr, pid_t pid, int cpu,
int fd, int group_fd, unsigned long flags)
{
int errno_saved = errno;
if ((fd != -1) && store_event(attr, pid, cpu, fd, group_fd, flags)) {
pr_err("test attr FAILED");
exit(128);
}
errno = errno_saved;
}
void test_attr__ready(void)
{
if (unlikely(test_attr__enabled) && !ready)
ready = true;
}
static int run_dir(const char *d, const char *perf)
{
char v[] = "-vvvvv";
int vcnt = min(verbose, (int) sizeof(v) - 1);
char cmd[3*PATH_MAX];
if (verbose > 0)
vcnt++;
scnprintf(cmd, 3*PATH_MAX, PYTHON " %s/attr.py -d %s/attr/ -p %s %.*s",
d, d, perf, vcnt, v);
return system(cmd) ? TEST_FAIL : TEST_OK;
}
int test__attr(struct test *test __maybe_unused, int subtest __maybe_unused)
{
struct stat st;
char path_perf[PATH_MAX];
char path_dir[PATH_MAX];
/* First try development tree tests. */
if (!lstat("./tests", &st))
return run_dir("./tests", "./perf");
/* Then installed path. */
snprintf(path_dir, PATH_MAX, "%s/tests", get_argv_exec_path());
snprintf(path_perf, PATH_MAX, "%s/perf", BINDIR);
if (!lstat(path_dir, &st) &&
!lstat(path_perf, &st))
return run_dir(path_dir, path_perf);
return TEST_SKIP;
}