Re: [Qemu-devel] [PATCH 3/3] migration/postcopy: discard_length must not be 0

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
To: Wei Yang <richardw.yang@linux.intel.com>
Cc: qemu-devel@nongnu.org, quintela@redhat.com
Subject: Re: [Qemu-devel] [PATCH 3/3] migration/postcopy: discard_length must not be 0
Date: Fri, 28 Jun 2019 16:17:30 +0100	[thread overview]
Message-ID: <20190628151730.GI2922@work-vm> (raw)
In-Reply-To: <20190627020822.15485-4-richardw.yang@linux.intel.com>

* Wei Yang (richardw.yang@linux.intel.com) wrote:
> Since we break the loop when there is no more page to discard, we are
> sure the following process would find some page to discard.
> 
> It is not necessary to check it again.
> 
> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> ---
>  migration/ram.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index b41b58ee54..246efe6939 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -2789,9 +2789,7 @@ static int postcopy_send_discard_bm_ram(MigrationState *ms,
>          } else {
>              discard_length = zero - one;
>          }
> -        if (discard_length) {
> -            postcopy_discard_send_range(ms, pds, one, discard_length);
> -        }
> +        postcopy_discard_send_range(ms, pds, one, discard_length);
>          current = one + discard_length;
>      }
>  
> -- 
> 2.19.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK