Re: [PATCH 2/2] generic: check the behavior of programs opening a lot of O_TMPFILE files

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Tue, Feb 12, 2019 at 04:42:21AM +0200, Amir Goldstein wrote:
> On Tue, Feb 12, 2019 at 4:18 AM Darrick J. Wong <darrick.wong@oracle.com> wrote:
> >
> > From: Darrick J. Wong <darrick.wong@oracle.com>
> >
> > Create a test (+ helper program) that opens as many unlinked files as it
> > possibly can on the scratch filesystem, then closes all the files at
> > once to stress-test unlinked file cleanup.  Add an xfs-specific test to
> > make sure that the fallback code doesn't bitrot.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > ---
> >  src/Makefile          |    2 -
> >  src/tmpfile.c         |  127 +++++++++++++++++++++++++++++++++++++++++++++++++
> >  tests/generic/710     |   65 +++++++++++++++++++++++++
> >  tests/generic/710.out |    2 +
> >  tests/generic/711     |   73 ++++++++++++++++++++++++++++
> >  tests/generic/711.out |    2 +
> >  tests/generic/group   |    2 +
> >  tests/xfs/736         |   71 +++++++++++++++++++++++++++
> >  tests/xfs/736.out     |    2 +
> >  tests/xfs/737         |   79 ++++++++++++++++++++++++++++++
> >  tests/xfs/737.out     |    2 +
> >  tests/xfs/group       |    2 +
> >  12 files changed, 428 insertions(+), 1 deletion(-)
> >  create mode 100644 src/tmpfile.c
> >  create mode 100755 tests/generic/710
> >  create mode 100644 tests/generic/710.out
> >  create mode 100755 tests/generic/711
> >  create mode 100644 tests/generic/711.out
> >  create mode 100755 tests/xfs/736
> >  create mode 100644 tests/xfs/736.out
> >  create mode 100755 tests/xfs/737
> >  create mode 100644 tests/xfs/737.out
> >
> >
> > diff --git a/src/Makefile b/src/Makefile
> > index 41826585..5fce881d 100644
> > --- a/src/Makefile
> > +++ b/src/Makefile
> > @@ -27,7 +27,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
> >         renameat2 t_getcwd e4compact test-nextquota punch-alternating \
> >         attr-list-by-handle-cursor-test listxattr dio-interleaved t_dir_type \
> >         dio-invalidate-cache stat_test t_encrypted_d_revalidate \
> > -       attr_replace_test swapon mkswap
> > +       attr_replace_test swapon mkswap tmpfile
> >
> >  SUBDIRS = log-writes perf
> >
> > diff --git a/src/tmpfile.c b/src/tmpfile.c
> 
> Let's go crazy and call it t_open_tmpfiles ?
> Missing .gitignore patch.

Will fix.

> ...
> > +/* Put an opened file on the unlinked list and leak the fd. */
> > +void leak_tmpfile(void)
> > +{
> > +       int fd = -1;
> > +       int ret;
> > +
> > +       /* Try to create an O_TMPFILE and leak the fd. */
> > +#ifdef O_TMPFILE
> > +       fd = open(".", O_TMPFILE | O_RDWR, 0644);
> 
> Pass in path as argv[1], so you won't need to cd $SCRATCH_MNT
> all the time. Or does it have a purpose?

Nope, just sillyness on my part.  Thanks for the suggestion.

--D

> Thanks,
> Amir.