Re: [Qemu-devel] [PATCH 01/12] nbd: rename read_sync and friends

[Vladimir Sementsov-Ogievskiy]

02.06.2017 16:49, Eric Blake wrote:
> On 06/02/2017 07:00 AM, Vladimir Sementsov-Ogievskiy wrote:
>
> > > > > 2. _sync suffix
> > > > >      _sync is related to the fact, that nbd_wr_syncv doesn't return if
> > > > s/fact,/fact/
> > > >
> > > > >      write to socket returns EAGAIN. In first implementation
> > > > > nbd_wr_syncv
> > > > >      just loops while getting EAGAIN, current implementation yields in
> > > > >      this case.
> > > > As mentioned in your followup, you may want to rewrite this to:
> > > >
> > > > _sync was originally used (back in commit 7a5ca864 when it was named
> > > > wr_sync) to indicate that we looped rather than returned on EAGAIN.  But
> > > > now we use qio_channel which yields on our behalf rather than giving us
> > > > EAGAIN.
> > > hmm, I like my wording (with adding note "... implementaion
> > > nbd_wr_syncv (was wr_sync in 7a5ca8648b) just ...")  more, because:
> > > 1. not only nbd_wr_syncv has that suffix, so nbd_wr_syncv should be
> > > mentioned (as we mention wr_sync)
> > > 2. I don't say about contrast between old and current, I say that they
> > > are similar.
> > Finally, are you OK with my wording? If I reroll, can I add your r-b?
> What final wording are you proposing (full paragraph, not a snippet)?

2. _sync suffix
   _sync is related to the fact that nbd_wr_syncv doesn't return if
   write to socket returns EAGAIN. In first implementation nbd_wr_syncv
   (was wr_sync in 7a5ca8648b) just loops while getting EAGAIN, current
   implementation yields in this case.
   Why to get rid of it:
   - it is normal for r/w functions to be synchronous, so having
     additional suffix for it looks redundant (contrariwise, we have
     _aio suffix for async functions)
   - _sync suffix in block layer is used when function does flush (so
     using it for other thing is confusing a bit)
   - keep function names short after adding nbd_ prefix

> > > > Reviewed-by: Eric Blake <address@hidden>
> At any rate, I already gave R-b for the code, so finessing the commit
> message doesn't change that if the code remains unchanged.

--
Best regards,
Vladimir