Re: [PATCH v2 0/4] vfs: track per-sb writeback errors and report them via fsinfo()

[Carlos Maiolino]

On Tue, Jul 10, 2018 at 10:01:23AM -0400, Jeff Layton wrote:
> v2: drop buffer.c patch to record wb errors when underlying blockdev
> flush fails. We may eventually want that, but at this point I don't have
> a clear way to test it to determine its efficacy.
> 
> At LSF/MM this year, the PostgreSQL developers mentioned that they'd
> like to have some mechanism to check whether there have been any
> writeback errors on a filesystem, without necessarily flushing any of
> the cached data first.
> 
> Given that we have a new fsinfo syscall being introduced, we may as well
> use it to report writeback errors on a per superblock basis. This allows
> us to provide the info that the PostgreSQL developers wanted, without
> needing to change an existing interface.
> 
> This seems to do the right thing when tested by hand, but I don't yet
> have an xfstest for it, since the syscall is still quite new. Once that
> goes in and we get fsinfo support in xfs_io, it should be rather
> trivial to roll a testcase for this.
> 

Whole patch sounds fine, you can add:

Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>

Cheers

> Al, if this looks ok, could you pull this into the branch where you
> have David's fsinfo patches queued up?
> 
> Thanks,
> Jeff
> 
> Jeff Layton (4):
>   vfs: track per-sb writeback errors
>   errseq: add a new errseq_scrape function
>   vfs: allow fsinfo to fetch the current state of s_wb_err
>   samples: extend test-fsinfo to access error_state
> 
>  fs/statfs.c                 |  9 +++++++++
>  include/linux/errseq.h      |  1 +
>  include/linux/fs.h          |  3 +++
>  include/linux/pagemap.h     |  5 ++++-
>  include/uapi/linux/fsinfo.h | 11 +++++++++++
>  lib/errseq.c                | 33 +++++++++++++++++++++++++++++++--
>  samples/statx/test-fsinfo.c | 13 +++++++++++++
>  7 files changed, 72 insertions(+), 3 deletions(-)
> 
> -- 
> 2.17.1
> 

-- 
Carlos