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From: Max Reitz <mreitz@redhat.com>
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Date: Mon, 13 Nov 2017 17:18:27 +0100
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Subject: Re: [Qemu-devel] [PATCH v2 for-2.11] block: Make bdrv_next() keep
 strong references
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-block@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>

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From: Max Reitz <mreitz@redhat.com>
To: Paolo Bonzini <pbonzini@redhat.com>, qemu-block@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>,
 qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <f5de0e4f-e561-c03a-d793-d205d6015ed0@redhat.com>
Subject: Re: [PATCH v2 for-2.11] block: Make bdrv_next() keep strong
 references
References: <20171110172545.32609-1-mreitz@redhat.com>
 <e4501a6c-3643-d0cb-4b6f-a6569646edad@redhat.com>
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On 2017-11-11 01:08, Paolo Bonzini wrote:
> On 10/11/2017 18:25, Max Reitz wrote:
>>          if (bs) {
>> +            bdrv_ref(bs);
>> +            bdrv_unref(old_bs);
>>              return bs;
>>          }
>=20
> Maybe instead goto...
>=20
>>          it->phase =3D BDRV_NEXT_MONITOR_OWNED;
>> +    } else {
>> +        old_bs =3D it->bs;
>>      }
>> =20
>>      /* Then return the monitor-owned BDSes without a BB attached. Ign=
ore all
>> @@ -467,18 +483,46 @@ BlockDriverState *bdrv_next(BdrvNextIterator *it=
)
>>          bs =3D it->bs;
>>      } while (bs && bdrv_has_blk(bs));
>=20
> ... here?

I wouldn't mind too much, but I don't think a goto there makes the code
easier to read.

Max

> Paolo
>=20
>> +    if (bs) {
>> +        bdrv_ref(bs);
>> +    }
>> +    bdrv_unref(old_bs);
>> +
>>      return bs;
>=20



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