static int do_child(int i)
{
long long elapsed_ms;
if (tst_process_state_wait2(getppid(), 'S') != 0) {
tst_brkm(TBROK | TERRNO, NULL,
"failed to wait for parent process's state");
}
tst_timer_start(CLOCK_MONOTONIC);
switch (test_cases[i].op_type) {
case OP_OPEN_RDONLY:
SAFE_OPEN(NULL, "file", O_RDONLY);
break;
case OP_OPEN_WRONLY:
SAFE_OPEN(NULL, "file", O_WRONLY);
break;
case OP_OPEN_RDWR:
SAFE_OPEN(NULL, "file", O_RDWR);
break;
case OP_TRUNCATE:
SAFE_TRUNCATE(NULL, "file", 0);
break;
default:
break;
}
tst_timer_stop();
elapsed_ms = tst_timer_elapsed_ms();
if (elapsed_ms < MIN_TIME_LIMIT * 1000) {
tst_resm(TPASS, "%s, unblocked within %ds",
test_cases[i].desc, MIN_TIME_LIMIT);
} else {
tst_resm(TFAIL, "%s, blocked too long %llims, "
"expected within %ds",
test_cases[i].desc, elapsed_ms, MIN_TIME_LIMIT);
}
tst_exit();
}
/* read_testfile - mmap testfile and read every page.
* This functions measures how many I/O and time it takes to fully
* read contents of test file.
*
* @do_readahead: call readahead prior to reading file content?
* @fname: name of file to test
* @fsize: how many bytes to read/mmap
* @read_bytes: returns difference of bytes read, parsed from /proc/<pid>/io
* @usec: returns how many microsecond it took to go over fsize bytes
* @cached: returns cached kB from /proc/meminfo
*/
static int read_testfile(struct tcase *tc, int do_readahead,
const char *fname, size_t fsize,
unsigned long *read_bytes, long long *usec,
unsigned long *cached)
{
int fd;
size_t i = 0;
long read_bytes_start;
unsigned char *p, tmp;
off_t offset = 0;
fd = SAFE_OPEN(fname, O_RDONLY);
if (do_readahead) {
do {
TEST(tc->readahead(fd, offset, fsize - offset));
if (TST_RET != 0) {
SAFE_CLOSE(fd);
return TST_ERR;
}
i++;
offset += readahead_length;
} while ((size_t)offset < fsize);
tst_res(TINFO, "readahead calls made: %zu", i);
*cached = get_cached_size();
/* offset of file shouldn't change after readahead */
offset = SAFE_LSEEK(fd, 0, SEEK_CUR);
if (offset == 0)
tst_res(TPASS, "offset is still at 0 as expected");
else
tst_res(TFAIL, "offset has changed to: %lu", offset);
}
tst_timer_start(CLOCK_MONOTONIC);
read_bytes_start = get_bytes_read();
p = SAFE_MMAP(NULL, fsize, PROT_READ, MAP_SHARED | MAP_POPULATE, fd, 0);
/* for old kernels, where MAP_POPULATE doesn't work, touch each page */
tmp = 0;
for (i = 0; i < fsize; i += pagesize)
tmp = tmp ^ p[i];
/* prevent gcc from optimizing out loop above */
if (tmp != 0)
tst_brk(TBROK, "This line should not be reached");
if (!do_readahead)
*cached = get_cached_size();
SAFE_MUNMAP(p, fsize);
*read_bytes = get_bytes_read() - read_bytes_start;
tst_timer_stop();
*usec = tst_timer_elapsed_us();
SAFE_CLOSE(fd);
return 0;
}
