Messages in this thread | | | Subject | Re: [V2 PATCH 9/9] vhost: zerocopy: poll vq in zerocopy callback | From | Shirley Ma <> | Date | Thu, 17 May 2012 08:34:22 -0700 |
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On Thu, 2012-05-17 at 10:50 +0800, Jason Wang wrote: > The problem is we may stop the tx queue when there no enough capacity > to > place packets, at this moment we depends on the tx interrupt to > re-enable the tx queue. So if we didn't poll the vhost during > callback, > guest may lose the tx interrupt to re-enable the tx queue which could > stall the whole tx queue.
VHOST_MAX_PEND should handle the capacity.
Hasn't the above situation been handled in handle_tx() code?: ... if (unlikely(num_pends > VHOST_MAX_PEND)) { tx_poll_start(net, sock); set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); break; } ...
Thanks Shirley
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