On Thu, Jul 28, 2022 at 01:37:08AM +0000, liuyd.fnst@xxxxxxxxxxx wrote:
> Hi, guys.
>
> Recently I hit a regression during test xfstest. Reverting this commit
> could fix that error.
>
> Reproduce steps (only nfs4.2 has this error):
> ```
> # cat local.config
>
> export TEST_DEV=127.0.0.1:/home/nfs/share0
>
> export TEST_DIR=/mnt/test
>
> export SCRATCH_DEV=127.0.0.1:/home/nfs/share1
ahahaaaa, NFS. I forgot that it sets st_blksize == 1048576, which will
trip this up.
Let me work on a fix to seek_sanity_test.c to make this work for xfs
realtime without breaking NFS. I /think/ the solution is to replace the
"if (...) goto done;" bit with something that queries FS_IOC_GETXATTR
and XFS_IOC_FSGEOMETRY to figure out if the file being tested is a
realtime file on an XFS filesystem, and set alloc_size to the rt extent
size.
/* Compute the file allocation unit size for an XFS file. */
static int detect_xfs_alloc_unit(int fd)
{
struct fsxattr fsx;
struct xfs_fsop_geom fsgeom;
int ret;
ret = ioctl(fd, XFS_IOC_FSGEOMETRY, &fsgeom);
if (ret)
return -1;
ret = ioctl(fd, FS_IOC_FSGETXATTR, &fsx);
if (ret)
return -1;
alloc_size = fsgeom.blocksize;
if (fsx.fsx_xflags & FS_XFLAG_REALTIME)
alloc_size *= fsgeom.rtextsize;
return 0;
}
should suffice to fix these testcase on xfs realtime without messing up
nfs.
--D
> export SCRATCH_MNT=/mnt/scratch
>
> export FSX_AVOID="-E"
>
> export NFS_MOUNT_OPTIONS="-o rw,relatime,vers=4.2"
>
>
> # ./check -nfs generic/285
>
> FSTYP -- nfs
>
> PLATFORM -- Linux/aarch64 hpe-apollo80-01-n00
> 5.14.0-131.el9.aarch64 #1 SMP PREEMPT_DYNAMIC Mon Jul 18 16:13:44 EDT 2022
>
> MKFS_OPTIONS -- 127.0.0.1:/home/nfs/share1
>
> MOUNT_OPTIONS -- -o rw,relatime,vers=4.2 -o
> context=system_u:object_r:root_t:s0 127.0.0.1:/home/nfs/share1 /mnt/scratch
>
>
>
> generic/285 2s ... [failed, exit status 1]- output mismatch (see
> /root/xfstests/results//generic/285.out.bad)
>
> --- tests/generic/285.out 2022-07-27 21:07:43.160268552 -0400
>
> +++ /root/xfstests/results//generic/285.out.bad 2022-07-27
> 21:31:27.887090532 -0400
>
> @@ -1 +1,3 @@
>
> QA output created by 285
>
> +seek sanity check failed!
>
> +(see /root/xfstests/results//generic/285.full for details)
>
> ...
>
> (Run 'diff -u /root/xfstests/tests/generic/285.out
> /root/xfstests/results//generic/285.out.bad' to see the entire diff)
>
> Ran: generic/285
>
> Failures: generic/285
>
> Failed 1 of 1 tests
>
>
> ```
>
> Reverting this commit then test pass.
> ```
> # git revert e861a30255c9780425ee5193325d30882fbe7410
> # make -j && make install -j
> ---snip---
> # ./check -nfs generic/285
>
> FSTYP -- nfs
>
> PLATFORM -- Linux/aarch64 hpe-apollo80-01-n00
> 5.14.0-131.el9.aarch64 #1 SMP PREEMPT_DYNAMIC Mon Jul 18 16:13:44 EDT 2022
>
> MKFS_OPTIONS -- 127.0.0.1:/home/nfs/share1
>
> MOUNT_OPTIONS -- -o rw,relatime,vers=4.2 -o
> context=system_u:object_r:root_t:s0 127.0.0.1:/home/nfs/share1 /mnt/scratch
>
>
>
> generic/285 1s ... 1s
>
> Ran: generic/285
>
> Passed all 1 tests
>
> ```
>
> On 6/29/22 04:21, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@xxxxxxxxxx>
> >
> > The seek sanity test tries to figure out a file space allocation unit by
> > calling stat and then using an iterative SEEK_DATA method to try to
> > detect a smaller blocksize based on SEEK_DATA's consultation of the
> > filesystem's internal block mapping. This was put in (AFAICT) because
> > XFS' stat implementation returns max(filesystem blocksize, PAGESIZE) for
> > most regular files.
> >
> > Unfortunately, for a realtime file with an extent size larger than a
> > single filesystem block this doesn't work at all because block mappings
> > still work at filesystem block granularity, but allocation units do not.
> > To fix this, detect the specific case where st_blksize != PAGE_SIZE and
> > trust the fstat results.
> >
> > Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> > ---
> > src/seek_sanity_test.c | 12 +++++++++++-
> > 1 file changed, 11 insertions(+), 1 deletion(-)
> >
> >
> > diff --git a/src/seek_sanity_test.c b/src/seek_sanity_test.c
> > index 76587b7f..1030d0c5 100644
> > --- a/src/seek_sanity_test.c
> > +++ b/src/seek_sanity_test.c
> > @@ -45,6 +45,7 @@ static int get_io_sizes(int fd)
> > off_t pos = 0, offset = 1;
> > struct stat buf;
> > int shift, ret;
> > + int pagesz = sysconf(_SC_PAGE_SIZE);
> >
> > ret = fstat(fd, &buf);
> > if (ret) {
> > @@ -53,8 +54,16 @@ static int get_io_sizes(int fd)
> > return ret;
> > }
> >
> > - /* st_blksize is typically also the allocation size */
> > + /*
> > + * st_blksize is typically also the allocation size. However, XFS
> > + * rounds this up to the page size, so if the stat blocksize is exactly
> > + * one page, use this iterative algorithm to see if SEEK_DATA will hint
> > + * at a more precise answer based on the filesystem's (pre)allocation
> > + * decisions.
> > + */
> > alloc_size = buf.st_blksize;
> > + if (alloc_size != pagesz)
> > + goto done;
> >
> > /* try to discover the actual alloc size */
> > while (pos == 0 && offset < alloc_size) {
> > @@ -80,6 +89,7 @@ static int get_io_sizes(int fd)
> > if (!shift)
> > offset += pos ? 0 : 1;
> > alloc_size = offset;
> > +done:
> > fprintf(stdout, "Allocation size: %ld\n", alloc_size);
> > return 0;
> >
> >
