[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3 00/13] main-loop: Get rid of fd_read_poll and
From: |
Paolo Bonzini |
Subject: |
Re: [Qemu-devel] [PATCH v3 00/13] main-loop: Get rid of fd_read_poll and qemu_set_fd_handler2 |
Date: |
Wed, 20 May 2015 09:39:34 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 |
On 20/05/2015 08:38, Fam Zheng wrote:
> On Wed, 05/20 08:26, Paolo Bonzini wrote:
>>
>>
>> On 19/05/2015 17:02, Stefan Hajnoczi wrote:
>>> 1. Convert everything like you converted qemu-nbd.c. This is a
>>> conservative approach and we can be confident that behavior is
>>> unchanged.
>>
>> So, that means whenever you change receive_disabled you call a new
>> callback on the peer? In addition, whenever the count of
>> receive-disabled ports switches from zero to non-zero or vice versa,
>> hubs need to inform all its ports.
>>
>> There are just two places that set/clear receive_disabled,
>> qemu_deliver_packet and qemu_flush_or_purge_queued_packets, but I
>> think a new API is needed to implement the callback for hubs
>> (qemu_send_enable/qemu_send_disable).
>
> I think .can_receive is the harder one, I'm not sure it's feasible - each
> device has its own set of conditions, so it will be a huge change.
The 1->0 transition is easy because it happens when message delivery
fails. I know the network code very little, but I think queuing exactly
one packet in this case should be acceptable. If this is true, the
network code can detect the 1->0 transition automatically.
The 0->1 transition should be easy in principle, because NICs are
supposed to call qemu_flush_queued_packets when it happens. Not that
they do, but you can find some very old and partial work in branch
rx-flush of my github repo.
Paolo
- [Qemu-devel] [PATCH v3 06/13] tap: Drop tap_can_send, (continued)
- [Qemu-devel] [PATCH v3 06/13] tap: Drop tap_can_send, Fam Zheng, 2015/05/18
- [Qemu-devel] [PATCH v3 11/13] xen_backend: Remove unused error handling of qemu_set_fd_handler, Fam Zheng, 2015/05/18
- [Qemu-devel] [PATCH v3 12/13] event-notifier: Always return 0 for posix implementation, Fam Zheng, 2015/05/18
- [Qemu-devel] [PATCH v3 13/13] iohandler: Change return type of qemu_set_fd_handler to "void", Fam Zheng, 2015/05/18
- [Qemu-devel] [PATCH v3 08/13] main-loop: Drop qemu_set_fd_handler2, Fam Zheng, 2015/05/18
- [Qemu-devel] [PATCH v3 07/13] Change qemu_set_fd_handler2(..., NULL, ...) to qemu_set_fd_handler, Fam Zheng, 2015/05/18
- Re: [Qemu-devel] [Qemu-block] [PATCH v3 00/13] main-loop: Get rid of fd_read_poll and qemu_set_fd_handler2, Stefan Hajnoczi, 2015/05/19