Re: [Qemu-devel] [PATCH 1/1] quorum: change vote rules for 64 bits hash

[Changlong Xie]

On 02/16/2016 01:10 AM, Eric Blake wrote:
> On 02/15/2016 02:52 AM, Changlong Xie wrote:
> > Before:
> > 1) vote_count > max: winner = candidate, update max
> > 2) vote_count <= max: do nothing
> > Current:
> > 1) vote_count > max: winner = candidate, update max
> > 2) vote_count = max: compare the value of winner with
> > candidate, if candidate->value.l == 0, winner = candidate,
> > else do nothing
> > 3) vote_count < max: do nothing
>
> This says what you did, but not why.  Can you demonstrate a scenario
> that is broken without the patch, as part of your commit message?

Surely, will do in next version.

> > Signed-off-by: Wen Congyang <address@hidden>
> > Signed-off-by: Changlong Xie <address@hidden>
> > ---
> >   block/quorum.c | 14 ++++++++++----
> >   1 file changed, 10 insertions(+), 4 deletions(-)
> >
> > diff --git a/block/quorum.c b/block/quorum.c
> > index a5ae4b8..e431ff4 100644
> > --- a/block/quorum.c
> > +++ b/block/quorum.c
> > @@ -446,7 +446,7 @@ static int quorum_compute_hash(QuorumAIOCB *acb, int i, 
> > QuorumVoteValue *hash)
> >       return 0;
> >   }
> >
> > -static QuorumVoteVersion *quorum_get_vote_winner(QuorumVotes *votes)
> > +static QuorumVoteVersion *quorum_get_vote_winner(QuorumVotes *votes, bool 
> > vote_error)
>
> Long line. Please wrap things to stay within 80 columns.

Ok

> >   {
> >       int max = 0;
> >       QuorumVoteVersion *candidate, *winner = NULL;
> > @@ -455,6 +455,12 @@ static QuorumVoteVersion 
> > *quorum_get_vote_winner(QuorumVotes *votes)
> >           if (candidate->vote_count > max) {
> >               max = candidate->vote_count;
> >               winner = candidate;
> > +            continue;
> > +        }
> > +        /* For 64 bit hash */
> > +        if (vote_error == true && candidate->vote_count == max
>
> s/ == true// (no need to do a redundant comparison of a bool against a
> bool).

Ok

Thanks
        -Xie

>