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// SPDX-License-Identifier: GPL-2.0
/*
* User Events Perf Events Test Program
*
* Copyright (c) 2021 Beau Belgrave <beaub@linux.microsoft.com>
*/
#include <errno.h>
#include <linux/user_events.h>
#include <linux/perf_event.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <unistd.h>
#include <asm/unistd.h>
#include "../kselftest_harness.h"
const char *data_file = "/sys/kernel/debug/tracing/user_events_data";
const char *status_file = "/sys/kernel/debug/tracing/user_events_status";
const char *id_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/id";
const char *fmt_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/format";
struct event {
__u32 index;
__u32 field1;
__u32 field2;
};
static long perf_event_open(struct perf_event_attr *pe, pid_t pid,
int cpu, int group_fd, unsigned long flags)
{
return syscall(__NR_perf_event_open, pe, pid, cpu, group_fd, flags);
}
static inline int status_check(char *status_page, int status_bit)
{
return status_page[status_bit >> 3] & (1 << (status_bit & 7));
}
static int get_id(void)
{
FILE *fp = fopen(id_file, "r");
int ret, id = 0;
if (!fp)
return -1;
ret = fscanf(fp, "%d", &id);
fclose(fp);
if (ret != 1)
return -1;
return id;
}
static int get_offset(void)
{
FILE *fp = fopen(fmt_file, "r");
int ret, c, last = 0, offset = 0;
if (!fp)
return -1;
/* Read until empty line */
while (true) {
c = getc(fp);
if (c == EOF)
break;
if (last == '\n' && c == '\n')
break;
last = c;
}
ret = fscanf(fp, "\tfield:u32 field1;\toffset:%d;", &offset);
fclose(fp);
if (ret != 1)
return -1;
return offset;
}
FIXTURE(user) {
int status_fd;
int data_fd;
};
FIXTURE_SETUP(user) {
self->status_fd = open(status_file, O_RDONLY);
ASSERT_NE(-1, self->status_fd);
self->data_fd = open(data_file, O_RDWR);
ASSERT_NE(-1, self->data_fd);
}
FIXTURE_TEARDOWN(user) {
close(self->status_fd);
close(self->data_fd);
}
TEST_F(user, perf_write) {
struct perf_event_attr pe = {0};
struct user_reg reg = {0};
int page_size = sysconf(_SC_PAGESIZE);
char *status_page;
struct event event;
struct perf_event_mmap_page *perf_page;
int id, fd, offset;
__u32 *val;
reg.size = sizeof(reg);
reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED,
self->status_fd, 0);
ASSERT_NE(MAP_FAILED, status_page);
/* Register should work */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
ASSERT_EQ(0, status_check(status_page, reg.status_bit));
/* Id should be there */
id = get_id();
ASSERT_NE(-1, id);
offset = get_offset();
ASSERT_NE(-1, offset);
pe.type = PERF_TYPE_TRACEPOINT;
pe.size = sizeof(pe);
pe.config = id;
pe.sample_type = PERF_SAMPLE_RAW;
pe.sample_period = 1;
pe.wakeup_events = 1;
/* Tracepoint attach should work */
fd = perf_event_open(&pe, 0, -1, -1, 0);
ASSERT_NE(-1, fd);
perf_page = mmap(NULL, page_size * 2, PROT_READ, MAP_SHARED, fd, 0);
ASSERT_NE(MAP_FAILED, perf_page);
/* Status should be updated */
ASSERT_NE(0, status_check(status_page, reg.status_bit));
event.index = reg.write_index;
event.field1 = 0xc001;
event.field2 = 0xc01a;
/* Ensure write shows up at correct offset */
ASSERT_NE(-1, write(self->data_fd, &event, sizeof(event)));
val = (void *)(((char *)perf_page) + perf_page->data_offset);
ASSERT_EQ(PERF_RECORD_SAMPLE, *val);
/* Skip over header and size, move to offset */
val += 3;
val = (void *)((char *)val) + offset;
/* Ensure correct */
ASSERT_EQ(event.field1, *val++);
ASSERT_EQ(event.field2, *val++);
}
int main(int argc, char **argv)
{
return test_harness_run(argc, argv);
}
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