Re: [LTP] [PATCH 3/5] Add test for file data integrity

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> +static void vectorize_buffer(struct iovec *vec, size_t vec_size, char *buf,
> +	size_t buf_size, int align)
> +{
> +	size_t i, len, chunk = align ? blocksize : 1;
> +
> +	memset(vec, 0, vec_size * sizeof(struct iovec));
> +	buf_size /= chunk;
> +
> +	for (i = 0; buf_size && i < vec_size; i++) {
> +		len = 1 + rand() % (buf_size + i + 1 - vec_size);

You have 1 + ... before the rand should it be buf_size:

i - 1 - vec_size

Also since 0 sized iov_len is actually correct, it means skip the entry,
we do not have to make sure that the length is > 0 here and neither we
need to make sure that we have enough buffer saved for the rest of the
vector.


> +		vec[i].iov_base = buf;
> +		vec[i].iov_len = len * chunk;
> +		buf += vec[i].iov_len;
> +		buf_size -= len;
> +	}
> +
> +	vec[vec_size - 1].iov_len += buf_size * chunk;
> +}
> +
> +static void update_filedata(const void *buf, size_t offset, size_t size)
> +{
> +	memcpy(filedata + offset, buf, size * sizeof(char));
                                                ^
						This is 1 by definition.
> +}
> +
> +static void do_write(void *buf, size_t offset, size_t size)
> +{
> +	SAFE_LSEEK(write_fd, offset, SEEK_SET);
> +	SAFE_WRITE(1, write_fd, buf, size);
> +}
> +
> +static void do_pwrite(void *buf, size_t offset, size_t size)
> +{
> +	SAFE_PWRITE(1, write_fd, buf, size, offset);
> +}
> +
> +static void do_writev(void *buf, size_t offset, size_t size)
> +{
> +	struct iovec vec[MAX_VEC] = {};
> +
> +	vectorize_buffer(vec, MAX_VEC, buf, size, !!directwr_flag);
> +	SAFE_LSEEK(write_fd, offset, SEEK_SET);
> +	SAFE_WRITEV(1, write_fd, vec, MAX_VEC);
> +}
> +
> +static void do_pwritev(void *buf, size_t offset, size_t size)
> +{
> +	struct iovec vec[MAX_VEC] = {};
> +
> +	vectorize_buffer(vec, MAX_VEC, buf, size, !!directwr_flag);
> +	SAFE_PWRITEV(1, write_fd, vec, MAX_VEC, offset);
> +}
> +
> +static void do_read(void *buf, size_t offset, size_t size)
> +{
> +	SAFE_LSEEK(read_fd, offset, SEEK_SET);
> +	SAFE_READ(1, read_fd, buf, size);
> +}
> +
> +static void do_pread(void *buf, size_t offset, size_t size)
> +{
> +	SAFE_PREAD(1, read_fd, buf, size, offset);
> +}
> +
> +static void do_readv(void *buf, size_t offset, size_t size)
> +{
> +	struct iovec vec[MAX_VEC] = {};
> +
> +	vectorize_buffer(vec, MAX_VEC, buf, size, !!directrd_flag);
> +	SAFE_LSEEK(read_fd, offset, SEEK_SET);
> +	SAFE_READV(1, read_fd, vec, MAX_VEC);
> +}
> +
> +static void do_preadv(void *buf, size_t offset, size_t size)
> +{
> +	struct iovec vec[MAX_VEC] = {};
> +
> +	vectorize_buffer(vec, MAX_VEC, buf, size, !!directrd_flag);
> +	SAFE_PREADV(1, read_fd, vec, MAX_VEC, offset);
> +}
> +
> +static int open_testfile(int flags)
> +{
> +	if ((flags & O_WRONLY) && directwr_flag)
> +		flags |= O_DIRECT;
> +
> +	if ((flags & O_RDONLY) && directrd_flag)
> +		flags |= O_DIRECT;
> +
> +	return SAFE_OPEN(TEST_FILENAME, flags, 0644);
> +}
> +
> +static void setup(void)
> +{
> +	struct statvfs statbuf;
> +	size_t pagesize;
> +
> +	srand(time(0));
> +	pagesize = SAFE_SYSCONF(_SC_PAGESIZE);
> +
> +	if (workdir_arg)
> +		SAFE_CHDIR(workdir_arg);
> +
> +	if (tst_parse_int(loop_arg, &loop_count, 0, INT_MAX))
> +		tst_brk(TBROK, "Invalid write loop count: %s", loop_arg);
> +
> +	write_fd = open_testfile(O_WRONLY | O_CREAT | O_TRUNC);
> +	read_fd = open_testfile(O_RDONLY);
> +	TEST(fstatvfs(write_fd, &statbuf));
> +
> +	if (TST_RET == -1)
> +		tst_brk(TBROK | TTERRNO, "fstatvfs() failed");
> +	else if (TST_RET)
> +		tst_brk(TBROK | TTERRNO, "Invalid fstatvfs() return value");
> +
> +	blocksize = statbuf.f_bsize;
> +	tst_res(TINFO, "Block size: %zu", blocksize);
> +	bufsize = 4 * MAX_VEC * MAX(pagesize, blocksize);
> +	filesize = 1024 * MAX(pagesize, blocksize);
> +	writebuf = SAFE_MMAP(NULL, bufsize, PROT_READ | PROT_WRITE,
> +		MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
> +	filedata = SAFE_MALLOC(filesize);
> +
> +	tst_set_max_runtime(bufsize * loop_count / (8 * 1024 * 1024));

I think that it may be better to define the test to be time based rather
than iteration based. If we decide that the default runtime would be 5
minutes the test would do as much iterations during that time as
possible and report how many it did at the end of the test. Possibly it
may warn if minimal amount of iterations wasn't reached. That would make
the test runtime much more predictable

> +}
> +
> +static void run(void)
> +{
> +	size_t start, length;
> +	int i, f, fails = 0;
> +
> +	/* Test data consistency between random writes */
> +	for (i = 0; i < loop_count; i++) {
> +		length = fill_buffer(writebuf, bufsize);
> +		start = rand() % (filesize + 1 - length);
> +
> +		/* Align offset to blocksize if needed */
> +		if (directrd_flag || directwr_flag)
> +			start = (start + blocksize / 2) & ~(blocksize - 1);
> +
> +		update_filedata(writebuf, start, length);
> +		f = rand() % ARRAY_SIZE(write_funcs);
> +		write_funcs[f](writebuf, start, length);
> +
> +		memset(writebuf, 0, length);
> +		f = rand() % ARRAY_SIZE(read_funcs);
> +		read_funcs[f](writebuf, start, length);
> +
> +		if (memcmp(writebuf, filedata + start, length)) {
> +			tst_res(TFAIL, "Partial data mismatch at [%zu:%zu]",
> +				start, start + length);
> +			fails++;
> +		}
> +	}
> +
> +	if (!fails)
> +		tst_res(TPASS, "Partial data are consistent");
> +
> +	/* Ensure that the testfile has the expected size */
> +	do_write(writebuf, filesize - blocksize, blocksize);
> +	update_filedata(writebuf, filesize - blocksize, blocksize);
> +
> +	/* Sync the testfile and clear cache */
> +	SAFE_CLOSE(read_fd);
> +	SAFE_FSYNC(write_fd);
> +	SAFE_FILE_PRINTF("/proc/sys/vm/drop_caches", "1");
> +	read_fd = open_testfile(O_RDONLY);
> +
> +	/* Check final file contents */
> +	for (start = 0; start < filesize; start += bufsize) {
> +		length = MIN(bufsize, filesize - start);
> +		SAFE_READ(1, read_fd, writebuf, length);
> +
> +		if (memcmp(writebuf, filedata + start, length)) {
> +			tst_res(TFAIL, "Final data mismatch at [%zu:%zu]",
> +				start, start + length);
> +			return;
> +		}
> +	}
> +
> +	tst_res(TPASS, "Final data are consistent");
> +}
> +
> +static void cleanup(void)
> +{
> +	SAFE_MUNMAP(writebuf, bufsize);
> +	free(filedata);
> +
> +	if (read_fd >= 0)
> +		SAFE_CLOSE(read_fd);
> +
> +	if (write_fd >= 0)
> +		SAFE_CLOSE(write_fd);
> +
> +	SAFE_UNLINK(TEST_FILENAME);
> +}
> +
> +static struct tst_test test = {
> +	.test_all = run,
> +	.setup = setup,
> +	.cleanup = cleanup,
> +	.needs_tmpdir = 1,
> +	.options = (struct tst_option[]) {
> +		{"c:", &loop_arg, "Number of write loops (default: 4096)"},
> +		{"d:", &workdir_arg, "Path to working directory"},
> +		{"W", &directwr_flag, "Use direct I/O for writing"},
> +		{"R", &directrd_flag, "Use direct I/O for reading"},
> +		{}
> +	}
> +};
> diff --git a/testcases/misc/lvm/datafiles/runfile.tpl b/testcases/misc/lvm/datafiles/runfile.tpl
> index 4c80e9391..ee733626f 100644
> --- a/testcases/misc/lvm/datafiles/runfile.tpl
> +++ b/testcases/misc/lvm/datafiles/runfile.tpl
> @@ -29,6 +29,10 @@
>  {fsname}_gf28 growfiles -W {fsname}_gf28 -b -D 0 -w -g 16b -C 1 -b -i 1000 -u {tempdir}/{fsname}/gfsparse-2-$$
>  {fsname}_gf29 growfiles -W {fsname}_gf29 -b -D 0 -r 1-4096 -R 0-33554432 -i 0 -L 60 -B 805306368 -C 1 -u {tempdir}/{fsname}/gfsparse-3-$$
>  {fsname}_gf30 growfiles -W {fsname}_gf30 -D 0 -b -i 0 -L 60 -u -B 1000b -e 1 -o O_RDWR,O_CREAT,O_SYNC -g 20480 -T 10 -t 20480 {tempdir}/{fsname}/gf-sync-$$
> +{fsname}_plough01 fsplough -d {tempdir}/{fsname}
> +{fsname}_plough02 fsplough -R -d {tempdir}/{fsname}
> +{fsname}_plough03 fsplough -W -d {tempdir}/{fsname}
> +{fsname}_plough04 fsplough -RW -d {tempdir}/{fsname}
>  {fsname}_rwtest01 rwtest -N {fsname}_rwtest01 -c -q -i 60s  -f sync 10%25000:rw-sync-$$ 500b:{tempdir}/{fsname}/rwtest01%f
>  {fsname}_rwtest02 rwtest -N {fsname}_rwtest02 -c -q -i 60s  -f buffered 10%25000:rw-buffered-$$ 500b:{tempdir}/{fsname}/rwtest02%f
>  {fsname}_rwtest03 rwtest -N {fsname}_rwtest03 -c -q -i 60s -n 2  -f buffered -s mmread,mmwrite -m random -Dv 10%25000:mm-buff-$$ 500b:{tempdir}/{fsname}/rwtest03%f
> -- 
> 2.46.0
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

-- 
Cyril Hrubis
chrubis@suse.cz

-- 
Mailing list info: https://lists.linux.it/listinfo/ltp