On Fri, Dec 1, 2017 at 8:38 AM, Chengguang Xu <cgxu@xxxxxxxxxxxx> wrote: > >> 在 2017年12月1日，下午12:13，Eryu Guan <eguan@xxxxxxxxxx> 写道： >> >> On Fri, Dec 01, 2017 at 12:04:44PM +0800, Chengguang Xu wrote: >>> Hi Eryu, >>> >>> Actually, in my another test case generic/470 will need to check whether fs supports syncfs or not. >>> I make shared infrastructure for checking that, and because it is common component >>> I post as an individual patch instead of including in the case of generic/470. >> >> I think "_require_xfs_io_command syncfs" should be fine, there's no need >> & not encouraged to add new binary & usage like this. If you want to run >> syncfs(2) to make sure the kernel actually supports it, you can add a >> new 'syncfs' switch case in _require_xfs_io_command. >> > > Failure of _require_xfs_io_command check leads to notrun, if we have several > sync patterns(combination of fsync/fdatasync/syncfs/sync) in an actual test case, > the case will lose downward compatibility for old kernel. > In this situation, we have to split test case though they look similar. > You have 2 options: Easy - split 2 tests - 1 requires syncfs and tests syncfs, 1 does not require and does not test syncfs Work - re-factor _require_xfs_io_command to _check_xfs_io_command that returns the error message but does not _notrun. use that hepler in your test to conditionally test syncfs. Anyway, I see people are not so fond of the delalloc "canary test". Perhaps a still simple and quick test would be to do small buffered write; sync; small direct io read? This test can still pass sometimes for buggy fs, but that will always be a problem with verifying that 'our' sync call did the job and not another thread in the system. Amir. -- To unsubscribe from this list: send the line "unsubscribe fstests" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
