From: Bruce Richardson <bruce.richardson@intel.com>
To: Jean-Mickael Guerin <jean-mickael.guerin@6wind.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH 2/2] ixgbe: don't override mbuf buffer length
Date: Thu, 4 Dec 2014 17:19:24 +0000 [thread overview]
Message-ID: <20141204171924.GB7732@bricha3-MOBL3> (raw)
In-Reply-To: <548095CD.5080607@6wind.com>
On Thu, Dec 04, 2014 at 06:11:41PM +0100, Jean-Mickael Guerin wrote:
> >>Which makes me think, that we probably shouldn't overwrite buf_len by rxq->mbuf_initializer.
> >>
> >I believe that it is perfectly safe to do so. All buffers from a mempool are meant
> >to be the same size, therefore reading the length of one buffer should tell you
> >what size all buffers are. If we do hit a scenario where we do need to support
> >variable size buffers from a single mempool, we can do that via the older unoptimized
> >code paths, I think, since it's a definite edge case.
> >
>
> I agree, and there is a place to store some values unique for all mbufs in a
> pool:
>
> struct rte_pktmbuf_pool_private {
> uint16_t mbuf_data_room_size; /**< Size of data space in each
> mbuf.*/
> };
>
> We could add a new field mbuf_buf_len here, it looks definitely better than
> new callbacks in rte_mempool.
>
> What do you think?
I think it's overkill.
I like the original suggest to allocate a buffer and pull the length settings from
there. Just add the checking so that if the allocation fails the whole setup fails.
If we can't allocate one mbuf from a pool, it's a pretty catastrophic error that
needs to be flagged ASAP. I wouldn't look to do anything up and above that.
/Bruce
next prev parent reply other threads:[~2014-12-04 17:30 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-04 14:26 [dpdk-dev] [PATCH 0/2] ixgbe: bug fixes for RX vector mode Jean-Mickael Guerin
2014-12-04 14:26 ` [dpdk-dev] [PATCH 1/2] ixgbe: fix setup of mbuf initializer template Jean-Mickael Guerin
2014-12-04 14:39 ` Bruce Richardson
2014-12-04 14:42 ` Ananyev, Konstantin
2014-12-04 15:15 ` Jean-Mickael Guerin
2014-12-04 16:22 ` Ananyev, Konstantin
2014-12-05 22:07 ` Thomas Monjalon
2014-12-04 14:26 ` [dpdk-dev] [PATCH 2/2] ixgbe: don't override mbuf buffer length Jean-Mickael Guerin
2014-12-04 14:40 ` Bruce Richardson
2014-12-04 14:50 ` Ananyev, Konstantin
2014-12-04 15:15 ` Bruce Richardson
2014-12-04 15:29 ` Ananyev, Konstantin
2014-12-04 15:32 ` Bruce Richardson
2014-12-04 16:03 ` Jean-Mickael Guerin
2014-12-04 16:20 ` Ananyev, Konstantin
2014-12-04 15:48 ` Thomas Monjalon
2014-12-04 16:05 ` Ananyev, Konstantin
2014-12-04 16:18 ` Ananyev, Konstantin
2014-12-04 16:57 ` Ananyev, Konstantin
2014-12-04 16:58 ` Bruce Richardson
2014-12-04 17:11 ` Jean-Mickael Guerin
2014-12-04 17:19 ` Bruce Richardson [this message]
2014-12-04 17:17 ` Ananyev, Konstantin
2014-12-04 17:22 ` Bruce Richardson
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