[LTP] [PATCH v2 5/5] cgroup: Add memcontrol02

[Petr Vorel]

Hi Richie,

> +static void alloc_pagecache_50M_check(void)
> +{
> +	const size_t size = MB(50);
> +	size_t current, file;
> +	const char *const file_key_fmt = is_v1_memcg ? "cache %zd" : "file %zd";
> +
> +	TEST(open(TMPDIR"/tmpfile", O_RDWR | O_CREAT));
FYI open() needs to have also mode:
TEST(open(TMPDIR"/tmpfile", O_RDWR | O_CREAT, 0600));

To fix error:

Although man open(2) suggest it could work:

The mode argument must be supplied if O_CREAT or O_TMPFILE is specified in flags; if it is not supplied, some arbitrary bytes from the stack will be applied as the file mode.

<fcntl.h> in glibc actually check for it and require it:

In function ‘open’,
    inlined from ‘alloc_pagecache_50M_check’ at memcontrol02.c:92:2,
    inlined from ‘test_memcg_current’ at memcontrol02.c:140:4:
/usr/include/bits/fcntl2.h:50:11: error: call to ‘__open_missing_mode’ declared with attribute error: open with O_CREAT or O_TMPFILE in second argument needs 3 arguments
   50 |           __open_missing_mode ();

Kind regards,
Petr