On Thu, Jun 13, 2013 at 05:03:05PM +0800, Liu Ping Fan wrote:
> From: Liu Ping Fan <pingf...@linux.vnet.ibm.com>
>
> Nested call caused by ->receive() will raise issue like deadlock,
> so postphone it to BH.
>
> Signed-off-by: Liu Ping Fan <pingf...@linux.vnet.ibm.com>
> ---
> net/queue.c | 40 ++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 38 insertions(+), 2 deletions(-)
Does this patch belong before the netqueue lock patch? The commit
history should be bisectable without temporary failures/deadlocks.
> diff --git a/net/queue.c b/net/queue.c
> index 58222b0..9c343ab 100644
> --- a/net/queue.c
> +++ b/net/queue.c
> @@ -24,6 +24,8 @@
> #include "net/queue.h"
> #include "qemu/queue.h"
> #include "net/net.h"
> +#include "block/aio.h"
> +#include "qemu/main-loop.h"
>
> /* The delivery handler may only return zero if it will call
> * qemu_net_queue_flush() when it determines that it is once again able
> @@ -183,6 +185,22 @@ static ssize_t qemu_net_queue_deliver_iov(NetQueue
> *queue,
> return ret;
> }
>
> +typedef struct NetQueBH {
This file uses "Queue" consistently, please don't add "Que" here.
> @@ -192,8 +210,17 @@ ssize_t qemu_net_queue_send(NetQueue *queue,
> {
> ssize_t ret;
>
> - if (queue->delivering || !qemu_can_send_packet_nolock(sender)) {
> + if (queue->delivering || !qemu_can_send_packet_nolock(sender)
> + || sender->send_queue->delivering) {
Not sure this is safe, we're only holding one NetClientState->peer_lock
and one NetQueue->lock. How can we access both queue->delivering and
sender->send_queue->delivering safely?
