Re: [RFC PATCH v3 8/9] vmci/vsock: check SO_RCVLOWAT before wake up reader

From: Vishnu Dasa <vdasa@vmware.com>
To: Stefano Garzarella <sgarzare@redhat.com>
Cc: Arseniy Krasnov <AVKrasnov@sberdevices.ru>,
	Bryan Tan <bryantan@vmware.com>,
	Pv-drivers <Pv-drivers@vmware.com>,
	"David S. Miller" <davem@davemloft.net>,
	"edumazet@google.com" <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	"kys@microsoft.com" <kys@microsoft.com>,
	"haiyangz@microsoft.com" <haiyangz@microsoft.com>,
	"sthemmin@microsoft.com" <sthemmin@microsoft.com>,
	"wei.liu@kernel.org" <wei.liu@kernel.org>,
	Dexuan Cui <decui@microsoft.com>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	Krasnov Arseniy <oxffffaa@gmail.com>,
	"virtualization@lists.linux-foundation.org" 
	<virtualization@lists.linux-foundation.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	kernel <kernel@sberdevices.ru>
Subject: Re: [RFC PATCH v3 8/9] vmci/vsock: check SO_RCVLOWAT before wake up reader
Date: Fri, 19 Aug 2022 04:46:56 +0000	[thread overview]
Message-ID: <873EFED7-1FB1-4545-899A-F57378C56FD3@vmware.com> (raw)
In-Reply-To: <20220808110153.fkxwwqbbqxz7wvgw@sgarzare-redhat>

> On Aug 8, 2022, at 4:01 AM, Stefano Garzarella <sgarzare@redhat.com> wrote:
> 
> On Wed, Aug 03, 2022 at 02:05:52PM +0000, Arseniy Krasnov wrote:
>> This adds extra condition to wake up data reader: do it only when number
>> of readable bytes >= SO_RCVLOWAT. Otherwise, there is no sense to kick
>> user,because it will wait until SO_RCVLOWAT bytes will be dequeued.

Nit: add space after comma.

> Ditto as previous patch.
> 
> @Bryan, @Vishnu, plaese, can you review/ack also this patch?

This patch looks good to me.

Thank you, Arseniy for running the new test with VMCI.  I also ran some
of our internal tests successfully with this patch series.

> Thanks,
> Stefano
> 
>> 
>> Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>

Reviewed-by: Vishnu Dasa <vdasa@vmware.com>

>> ---
>> net/vmw_vsock/vmci_transport_notify.c        | 2 +-
>> net/vmw_vsock/vmci_transport_notify_qstate.c | 4 ++--
>> 2 files changed, 3 insertions(+), 3 deletions(-)
>> 
>> diff --git a/net/vmw_vsock/vmci_transport_notify.c b/net/vmw_vsock/vmci_transport_notify.c
>> index 852097e2b9e6..7c3a7db134b2 100644
>> --- a/net/vmw_vsock/vmci_transport_notify.c
>> +++ b/net/vmw_vsock/vmci_transport_notify.c
>> @@ -307,7 +307,7 @@ vmci_transport_handle_wrote(struct sock *sk,
>>      struct vsock_sock *vsk = vsock_sk(sk);
>>      PKT_FIELD(vsk, sent_waiting_read) = false;
>> #endif
>> -      sk->sk_data_ready(sk);
>> +      vsock_data_ready(sk);
>> }
>> 
>> static void vmci_transport_notify_pkt_socket_init(struct sock *sk)
>> diff --git a/net/vmw_vsock/vmci_transport_notify_qstate.c b/net/vmw_vsock/vmci_transport_notify_qstate.c
>> index 12f0cb8fe998..e96a88d850a8 100644
>> --- a/net/vmw_vsock/vmci_transport_notify_qstate.c
>> +++ b/net/vmw_vsock/vmci_transport_notify_qstate.c
>> @@ -84,7 +84,7 @@ vmci_transport_handle_wrote(struct sock *sk,
>>                          bool bottom_half,
>>                          struct sockaddr_vm *dst, struct sockaddr_vm *src)
>> {
>> -      sk->sk_data_ready(sk);
>> +      vsock_data_ready(sk);
>> }
>> 
>> static void vsock_block_update_write_window(struct sock *sk)
>> @@ -282,7 +282,7 @@ vmci_transport_notify_pkt_recv_post_dequeue(
>>              /* See the comment in
>>               * vmci_transport_notify_pkt_send_post_enqueue().
>>               */
>> -              sk->sk_data_ready(sk);
>> +              vsock_data_ready(sk);
>>      }
>> 
>>      return err;
>> --
>> 2.25.1