On Thu, Feb 15, 2018 at 2:47 PM, Santosh Shilimkar
<santosh.shilim...@oracle.com> wrote:
> On 2/15/2018 10:49 AM, Sowmini Varadhan wrote:
>>
>> If the MSG_ZEROCOPY flag is specified with rds_sendmsg(), and,
>> if the SO_ZEROCOPY socket option has been set on the PF_RDS socket,
>> application pages sent down with rds_sendmsg() are pinned.
>>
>> The pinning uses the accounting infrastructure added by
>> Commit a91dbff551a6 ("sock: ulimit on MSG_ZEROCOPY pages")
>>
>> The payload bytes in the message may not be modified for the
>> duration that the message has been pinned. A multi-threaded
>> application using this infrastructure may thus need to be notified
>> about send-completion so that it can free/reuse the buffers
>> passed to rds_sendmsg(). Notification of send-completion will
>> identify each message-buffer by a cookie that the application
>> must specify as ancillary data to rds_sendmsg().
>> The ancillary data in this case has cmsg_level == SOL_RDS
>> and cmsg_type == RDS_CMSG_ZCOPY_COOKIE.
>>
>> Signed-off-by: Sowmini Varadhan <sowmini.varad...@oracle.com>
>> ---
>
>
> Acked-by: Santosh Shilimkar <santosh.shilim...@oracle.com>Acked-by: Willem de Bruijn <will...@google.com>
