* Darrick J. Wong <djwong@xxxxxxxxxx>:
> On Thu, Apr 14, 2022 at 10:22:58AM -0400, Eric Whitney wrote:
> > When run on ext4 with sufficiently fast x86_64 hardware, generic/130
> > sometimes fails because xfs_io can report rate values as -nan:
> > 0.000000 bytes, 0 ops; 0.0000 sec (-nan bytes/sec and -nan ops/sec)
> >
> > _filter_xfs_io matches the strings 'inf' or 'nan', but not '-nan'. In
> > that case it fails to convert the actual output to a normalized form
> > matching generic/130's golden output. Extend the regular expression
> > used to match xfs_io's output to fix this.
> >
> > Signed-off-by: Eric Whitney <enwlinux@xxxxxxxxx>
> > ---
> > common/filter | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/common/filter b/common/filter
> > index 5fe86756..5b20e848 100644
> > --- a/common/filter
> > +++ b/common/filter
> > @@ -168,9 +168,9 @@ common_line_filter()
> >
> > _filter_xfs_io()
> > {
> > - # Apart from standard numeric values, we also filter out 'inf' and 'nan'
> > - # which can result from division in some cases
> > - sed -e "s/[0-9/.]* [GMKiBbytes]*, [0-9]* ops\; [0-9/:. sec]* ([infa0-9/.]* [EPGMKiBbytes]*\/sec and [infa0-9/.]* ops\/sec)/XXX Bytes, X ops\; XX:XX:XX.X (XXX YYY\/sec and XXX ops\/sec)/"
> > + # Apart from standard numeric values, we also filter out 'inf', 'nan', and
> > + # '-nan' which can result from division in some cases
> > + sed -e "s/[0-9/.]* [GMKiBbytes]*, [0-9]* ops\; [0-9/:. sec]* ([infa0-9/.-]* [EPGMKiBbytes]*\/sec and [infa0-9/.-]* ops\/sec)/XXX Bytes, X ops\; XX:XX:XX.X (XXX YYY\/sec and XXX ops\/sec)/"
>
> /me squints at this regular expression and /thinks/ its ok.
>
> Took me a while to figure out "infa" tho. :P
Hi Darrick:
Yeah, me too. I initially thought that string would not match 'nan', but
then discovered bracket expressions after having not used sed in a very long
time. It's a sloppy match - it'll recognize fan0 as well as 'inf' or 'nan',
etc. - and I guess the idea is that's good enough for filtering expected output
from xfs_io while being concise. The sed documentation suggests that a '-' on
the beginning or end of the bracket expression will be treated literally, and
not as a metacharacter (part of a range), so we should be good there.
>
> Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Thanks very much for your review!
Eric
>
> --D
>
> > }
> >
> > # Also filter out the offset part of xfs_io output
> > --
> > 2.30.2
> >
