Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 19 Jul 2022 14:48:57 +0200
From:   Stefano Garzarella <sgarzare@redhat.com>
To:     Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Cc:     "David S. Miller" <davem@davemloft.net>,
        "edumazet@google.com" <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Krasnov Arseniy <oxffffaa@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        kernel <kernel@sberdevices.ru>
Subject: Re: [RFC PATCH v1 2/3] virtio/vsock: use 'target' in notify_poll_in,
 callback.
Message-ID: <20220719124857.akv25sgp6np3pdaw@sgarzare-redhat>
References: <c8de13b1-cbd8-e3e0-5728-f3c3648c69f7@sberdevices.ru>
 <358f8d52-fd88-ad2e-87e2-c64bfa516a58@sberdevices.ru>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Disposition: inline
In-Reply-To: <358f8d52-fd88-ad2e-87e2-c64bfa516a58@sberdevices.ru>
Precedence: bulk

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@sberdevices.ru>
>---
> 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;

Anyway, I think we also need to fix the other transports (vmci and 
hyperv), what do you think?

Thanks,
Stefano