Re: [RFC PATCH v1 2/3] virtio/vsock: use 'target' in notify_poll_in, callback.

From: Arseniy Krasnov
Date: Wed Jul 20 2022 - 01:38:21 EST


On 19.07.2022 15:48, Stefano Garzarella wrote:
> On Mon, Jul 18, 2022 at 08:17:31AM +0000, Arseniy Krasnov wrote:
>> This callback controls setting of POLLIN,POLLRDNORM output bits
>> of poll() syscall,but in some cases,it is incorrectly to set it,
>> when socket has at least 1 bytes of available data. Use 'target'
>> which is already exists and equal to sk_rcvlowat in this case.
>>
>> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
>> ---
>> net/vmw_vsock/virtio_transport_common.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
>> index ec2c2afbf0d0..591908740992 100644
>> --- a/net/vmw_vsock/virtio_transport_common.c
>> +++ b/net/vmw_vsock/virtio_transport_common.c
>> @@ -634,7 +634,7 @@ virtio_transport_notify_poll_in(struct vsock_sock *vsk,
>>                 size_t target,
>>                 bool *data_ready_now)
>> {
>> -    if (vsock_stream_has_data(vsk))
>> +    if (vsock_stream_has_data(vsk) >= target)
>>         *data_ready_now = true;
>>     else
>>         *data_ready_now = false;
>
> Perhaps we can take the opportunity to clean up the code in this way:
>
>     *data_ready_now = vsock_stream_has_data(vsk) >= target;
Ack
>
> Anyway, I think we also need to fix the other transports (vmci and hyperv), what do you think?
For vmci it is look clear to fix it. For hyperv i need to check it more, because it already
uses some internal target value.
>
> Thanks,
> Stefano
>