[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default
From: |
Peter Lieven |
Subject: |
Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default |
Date: |
Fri, 15 Feb 2013 15:27:52 +0100 |
Am 15.02.2013 um 14:32 schrieb Stefan Hajnoczi <address@hidden>:
> On Fri, Feb 15, 2013 at 10:32:31AM +0100, Peter Lieven wrote:
>> historically the kernel queues packets two times. once
>> at the device and second in qdisc. this is believed to cause
>> interface stalls if one of these queues overruns.
>>
>> setting IFF_ONE_QUEUE is the default in kernels >= 3.8. the
>> flag is ignored since then. see kernel commit
>> 5d097109257c03a71845729f8db6b5770c4bbedc
>>
>> v2:
>> - do only set the flag on linux as it breaks macvtap
>> - define IFF_ONE_QUEUE in tap-linux.h
>>
>> Signed-off-by: Peter Lieven <address@hidden>
>> ---
>> net/tap-linux.c | 4 ++++
>> net/tap-linux.h | 1 +
>> 2 files changed, 5 insertions(+)
>>
>> diff --git a/net/tap-linux.c b/net/tap-linux.c
>> index a953189..d49f2fd 100644
>> --- a/net/tap-linux.c
>> +++ b/net/tap-linux.c
>> @@ -51,6 +51,10 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
>> memset(&ifr, 0, sizeof(ifr));
>> ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
>>
>> +#ifdef __linux__
>> + ifr.ifr_flags |= IFF_ONE_QUEUE;
>> +#endif
>
> tap-linux.c <--- notice the filename
i know. is qemu really using it on MACs?
Peter
>
> Perhaps the solution is to try with IFF_ONE_QUEUE. If the result is
> -EINVAL, try without.
>
> Stefan
- Re: [Qemu-devel] tap devices not receiving packets from a bridge, (continued)
- Re: [Qemu-devel] tap devices not receiving packets from a bridge, Peter Lieven, 2013/02/12
- Re: [Qemu-devel] tap devices not receiving packets from a bridge, Michael S. Tsirkin, 2013/02/12
- [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/15
- Re: [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Stefan Hajnoczi, 2013/02/15
- Re: [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/15
- Re: [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Christian Borntraeger, 2013/02/15
- Re: [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/15
- Re: [Qemu-devel] [PATCH] tap: set IFF_ONE_QUEUE per default, Christian Borntraeger, 2013/02/15
- [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/15
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Stefan Hajnoczi, 2013/02/15
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default,
Peter Lieven <=
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Christian Borntraeger, 2013/02/15
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/18
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/25
- Re: [Qemu-devel] [PATCHv2] tap: set IFF_ONE_QUEUE per default, Christian Borntraeger, 2013/02/25
- [Qemu-devel] [PATCHv3] tap: set IFF_ONE_QUEUE per default, Peter Lieven, 2013/02/25
- Re: [Qemu-devel] [PATCHv3] tap: set IFF_ONE_QUEUE per default, Michael S. Tsirkin, 2013/02/25
- Re: [Qemu-devel] [PATCHv3] tap: set IFF_ONE_QUEUE per default, Stefan Hajnoczi, 2013/02/25