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From: Jason Wang <jasowang@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>,
	wangyunjian <wangyunjian@huawei.com>
Cc: netdev@vger.kernel.org, willemdebruijn.kernel@gmail.com,
	virtualization@lists.linux-foundation.org,
	jerry.lilijun@huawei.com, chenchanghu@huawei.com,
	xudingke@huawei.com, brian.huangbin@huawei.com
Subject: Re: [PATCH net v2 2/2] vhost_net: fix high cpu load when sendmsg fails
Date: Thu, 17 Dec 2020 11:19:57 +0800	[thread overview]
Message-ID: <482e71e6-2c85-346f-d7f9-10db6a5c716b@redhat.com> (raw)
In-Reply-To: <20201216042027-mutt-send-email-mst@kernel.org>


On 2020/12/16 下午5:23, Michael S. Tsirkin wrote:
> On Wed, Dec 16, 2020 at 04:20:37PM +0800, wangyunjian wrote:
>> From: Yunjian Wang<wangyunjian@huawei.com>
>>
>> Currently we break the loop and wake up the vhost_worker when
>> sendmsg fails. When the worker wakes up again, we'll meet the
>> same error. This will cause high CPU load. To fix this issue,
>> we can skip this description by ignoring the error. When we
>> exceeds sndbuf, the return value of sendmsg is -EAGAIN. In
>> the case we don't skip the description and don't drop packet.
> Question: with this patch, what happens if sendmsg is interrupted by a signal?


Since we use MSG_DONTWAIT, we don't need to care about signal I think.

Thanks


>
>


  parent reply	other threads:[~2020-12-17  3:22 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-15  1:48 [PATCH net 0/2] fixes for vhost_net wangyunjian
2020-12-15  1:48 ` [PATCH net 1/2] vhost_net: fix ubuf refcount incorrectly when sendmsg fails wangyunjian
2020-12-15  2:45   ` Willem de Bruijn
2020-12-15  7:51     ` wangyunjian
2020-12-15  1:48 ` [PATCH net 2/2] vhost_net: fix high cpu load " wangyunjian
2020-12-15  4:09   ` Jason Wang
2020-12-15  8:03     ` wangyunjian
2020-12-16  5:56       ` Jason Wang
2020-12-16  7:43         ` wangyunjian
2020-12-16  7:47           ` Jason Wang
2020-12-16  8:20 ` [PATCH net v2 0/2] fixes for vhost_net wangyunjian
2020-12-16  8:20   ` [PATCH net v2 1/2] vhost_net: fix ubuf refcount incorrectly when sendmsg fails wangyunjian
2020-12-16 14:17     ` Willem de Bruijn
2020-12-16 20:56     ` Michael S. Tsirkin
2020-12-16  8:20   ` [PATCH net v2 2/2] vhost_net: fix high cpu load " wangyunjian
2020-12-16  9:23     ` Michael S. Tsirkin
2020-12-17  2:38       ` wangyunjian
2020-12-17  3:19       ` Jason Wang [this message]
2020-12-21 23:07     ` Willem de Bruijn
2020-12-22  4:41       ` Jason Wang
2020-12-22 14:24         ` Willem de Bruijn
2020-12-23  2:53           ` Jason Wang
2020-12-23 13:21             ` wangyunjian
2020-12-23 13:48               ` Willem de Bruijn
2020-12-23  2:46         ` wangyunjian

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