Re: [Qemu-devel] [PATCH v3 3/6] migration: remove unnecessary variables len in QIOChannelRDMA

[858585 jemmy]

On Tue, May 8, 2018 at 10:19 PM, Dr. David Alan Gilbert
<address@hidden> wrote:
> * Lidong Chen (address@hidden) wrote:
>> Because qio_channel_rdma_writev and qio_channel_rdma_readv maybe invoked
>> by different threads concurrently, this patch removes unnecessary variables
>> len in QIOChannelRDMA and use local variable instead.
>>
>> Signed-off-by: Lidong Chen <address@hidden>
>> Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>> Reviewed-by: Daniel P. address@hidden>
>
> Note there's a ' <' missing somehow; minor fix up during commit
> hopefully.
>
> Dave

Sorry for this mistake, I will check more carefully.

>
>> ---
>>  migration/rdma.c | 15 +++++++--------
>>  1 file changed, 7 insertions(+), 8 deletions(-)
>>
>> diff --git a/migration/rdma.c b/migration/rdma.c
>> index c745427..f5c1d02 100644
>> --- a/migration/rdma.c
>> +++ b/migration/rdma.c
>> @@ -404,7 +404,6 @@ struct QIOChannelRDMA {
>>      QIOChannel parent;
>>      RDMAContext *rdma;
>>      QEMUFile *file;
>> -    size_t len;
>>      bool blocking; /* XXX we don't actually honour this yet */
>>  };
>>
>> @@ -2640,6 +2639,7 @@ static ssize_t qio_channel_rdma_writev(QIOChannel *ioc,
>>      int ret;
>>      ssize_t done = 0;
>>      size_t i;
>> +    size_t len = 0;
>>
>>      CHECK_ERROR_STATE();
>>
>> @@ -2659,10 +2659,10 @@ static ssize_t qio_channel_rdma_writev(QIOChannel 
>> *ioc,
>>          while (remaining) {
>>              RDMAControlHeader head;
>>
>> -            rioc->len = MIN(remaining, RDMA_SEND_INCREMENT);
>> -            remaining -= rioc->len;
>> +            len = MIN(remaining, RDMA_SEND_INCREMENT);
>> +            remaining -= len;
>>
>> -            head.len = rioc->len;
>> +            head.len = len;
>>              head.type = RDMA_CONTROL_QEMU_FILE;
>>
>>              ret = qemu_rdma_exchange_send(rdma, &head, data, NULL, NULL, 
>> NULL);
>> @@ -2672,8 +2672,8 @@ static ssize_t qio_channel_rdma_writev(QIOChannel *ioc,
>>                  return ret;
>>              }
>>
>> -            data += rioc->len;
>> -            done += rioc->len;
>> +            data += len;
>> +            done += len;
>>          }
>>      }
>>
>> @@ -2768,8 +2768,7 @@ static ssize_t qio_channel_rdma_readv(QIOChannel *ioc,
>>              }
>>          }
>>      }
>> -    rioc->len = done;
>> -    return rioc->len;
>> +    return done;
>>  }
>>
>>  /*
>> --
>> 1.8.3.1
>>
> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK