Re: [Qemu-devel] [Qemu-block] [PATCH v3 00/13] main-loop: Get rid of fd_read_poll and qemu_set_fd_handler2

From: Fam Zheng <famz@redhat.com>
To: Stefan Hajnoczi <stefanha@gmail.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org, Juan Quintela <quintela@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	qemu-devel@nongnu.org, Vincenzo Maffione <v.maffione@gmail.com>,
	"Vassili Karpov (malc)" <av1474@comtv.ru>,
	Gerd Hoffmann <kraxel@redhat.com>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	Amit Shah <amit.shah@redhat.com>,
	Giuseppe Lettieri <g.lettieri@iet.unipi.it>,
	Luigi Rizzo <rizzo@iet.unipi.it>
Subject: Re: [Qemu-devel] [Qemu-block] [PATCH v3 00/13] main-loop: Get rid of fd_read_poll and qemu_set_fd_handler2
Date: Wed, 20 May 2015 14:38:03 +0800	[thread overview]
Message-ID: <20150520063803.GE6219@ad.nay.redhat.com> (raw)
In-Reply-To: <555C2917.2060101@redhat.com>

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.

Fam