> -----Original Message----- > From: David Miller [mailto:da...@davemloft.net] > Sent: Thursday, September 17, 2015 1:11 PM > To: KY Srinivasan <k...@microsoft.com> > Cc: david.lai...@aculab.com; alexander.du...@gmail.com; Haiyang Zhang > <haiya...@microsoft.com>; vkuzn...@redhat.com; netdev@vger.kernel.org; > linux-ker...@vger.kernel.org; jasow...@redhat.com > Subject: Re: [PATCH net-next RFC] net: increase LL_MAX_HEADER for Hyper-V > > From: KY Srinivasan <k...@microsoft.com> > Date: Thu, 17 Sep 2015 19:52:01 +0000 > > > > > > >> -----Original Message----- > >> Have a pre-cooked ring of buffers for these descriptors that you can > >> point the chip at. No per-packet allocation is necessary at all. > > > > Even if I had a ring of buffers, I would still need to manage the life cycle > > of these buffers - selecting an unused one on the transmit path and marking > > it used (atomically). > > Have one per TX ring entry, then the lifetime matches the lifetime of the > TX entry itself and therefore you need do nothing.
Yes, I understand. Unfortunately, the ring buffer used on Hyper-V to send the packets to the host is not managed as a traditional TX ring entries - it is not fixed size and a given packet can wrap around and lastly, I think the management of space on the ring buffer is not tied to the act of completing the send operation. That is why we have an explicit "send complete" message. I am working on moving the model to more closely match the hardware model but it will take some time. For now, I will implement a very light weight mechanism for managing the additional memory needed. Regards, K. Y > > That's the whole idea. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
