From: Jamal Hadi Salim <jhs@mojatatu•com>
To: John Fastabend <john.fastabend@gmail•com>,
"Amir Vadai\"" <amir@vadai•me>
Cc: ogerlitz@mellanox•com, jiri@resnulli•us,
jeffrey.t.kirsher@intel•com, netdev@vger•kernel.org,
davem@davemloft•net
Subject: Re: [net-next PATCH 7/7] net: ixgbe: add support for tc_u32 offload
Date: Wed, 3 Feb 2016 07:46:01 -0500 [thread overview]
Message-ID: <56B1F689.5040609@mojatatu.com> (raw)
In-Reply-To: <56B1D5D2.7040807@gmail.com>
On 16-02-03 05:26 AM, John Fastabend wrote:
> On 16-02-03 02:07 AM, Amir Vadai" wrote:
>> On Wed, Feb 03, 2016 at 01:29:59AM -0800, John Fastabend wrote:
>>> This adds initial support for offloading the u32 tc classifier. This
>>> initial implementation only implements a few base matches and actions
>>> to illustrate the use of the infrastructure patches.
>>>
>>> However it is an interesting subset because it handles the u32 next
>>> hdr logic to correctly map tcp packets from ip headers using the ihl
>>> and protocol fields. After this is accepted we can extend the match
>>> and action fields easily by updating the model header file.
>>>
>>> Also only the drop action is supported initially.
>>>
>>> Here is a short test script,
>>>
>>> #tc qdisc add dev eth4 ingress
>>> #tc filter add dev eth4 parent ffff: protocol ip \
>>> u32 ht 800: order 1 \
>>> match ip dst 15.0.0.1/32 match ip src 15.0.0.2/32 action drop
>>>
>>> <-- hardware has dst/src ip match rule installed -->
>>>
>>> #tc filter del dev eth4 parent ffff: prio 49152
>>> #tc filter add dev eth4 parent ffff: protocol ip prio 99 \
>>> handle 1: u32 divisor 1
>>> #tc filter add dev eth4 protocol ip parent ffff: prio 99 \
>>> u32 ht 800: order 1 link 1: \
>>> offset at 0 mask 0f00 shift 6 plus 0 eat match ip protocol 6 ff
>>> #tc filter add dev eth4 parent ffff: protocol ip \
>>> u32 ht 1: order 3 match tcp src 23 ffff action drop
>>>
>>> <-- hardware has tcp src port rule installed -->
>>>
>>> #tc qdisc del dev eth4 parent ffff:
>>>
>>> <-- hardware cleaned up -->
>>>
>>> Signed-off-by: John Fastabend <john.r.fastabend@intel•com>
>>> ---
>>> drivers/net/ethernet/intel/ixgbe/ixgbe.h | 3
>>> drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c | 6 -
>>> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 196 ++++++++++++++++++++++
>>> 3 files changed, 198 insertions(+), 7 deletions(-)
>>>
>>
>> What are you doing w.r.t priorities? Are the filters processed by the
>> order of the priorities?
>>
>
> The rules are put in order by the handles which is populated in
> my command above such that 'ht 1: order 3' gives handle 1::3 and
> 'ht 800: order 1' gives 800::1. Take a look at this block in cls_u32
>
> if (err == 0) {
> struct tc_u_knode __rcu **ins;
> struct tc_u_knode *pins;
>
> ins = &ht->ht[TC_U32_HASH(handle)];
> for (pins = rtnl_dereference(*ins); pins;
> ins = &pins->next, pins = rtnl_dereference(*ins))
> if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
> break;
>
> RCU_INIT_POINTER(n->next, pins);
> rcu_assign_pointer(*ins, n);
> u32_replace_hw_knode(tp, n);
> *arg = (unsigned long)n;
> return 0;
>
>
> If you leave ht and order off the tc cli I believe 'tc' just
> picks some semi-arbitrary ones for you. I've been in the habit
> of always specifying them even for software filters.
>
The default table id is essentially 0x800. Default bucket is 0.
"order" essentially is the filter id. And given you can link tables
(Nice work John!); essentially the ht:bucket:nodeid is an "address" to
a specific filter on a specific table and when makes sense a specific
hash bucket. Some other way to look at it is as a way to construct
a mapping to a TCAM key.
What John is doing is essentially taking the nodeid and trying to use
it as a priority. In otherwise the abstraction is reduced to a linked
list in which the ordering is how the list is traversed.
It may work in this case, but i am for being able to explicitly specify
priorities.
cheers,
jamal
next prev parent reply other threads:[~2016-02-03 12:46 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-03 9:27 [net-next PATCH 0/7] tc offload for cls_u32 on ixgbe John Fastabend
2016-02-03 9:27 ` [net-next PATCH 1/7] net: rework ndo tc op to consume additional qdisc handle parameter John Fastabend
2016-02-03 9:58 ` kbuild test robot
2016-02-03 9:59 ` kbuild test robot
2016-02-03 11:44 ` kbuild test robot
2016-02-03 9:28 ` [net-next PATCH 2/7] net: rework setup_tc ndo op to consume general tc operand John Fastabend
2016-02-03 9:28 ` [net-next PATCH 3/7] net: sched: add cls_u32 offload hooks for netdevs John Fastabend
2016-02-03 10:14 ` kbuild test robot
2016-02-04 13:18 ` Amir Vadai"
2016-02-09 11:09 ` Fastabend, John R
2016-02-03 9:28 ` [net-next PATCH 4/7] net: add tc offload feature flag John Fastabend
2016-02-03 9:29 ` [net-next PATCH 5/7] net: tc: helper functions to query action types John Fastabend
2016-02-03 9:29 ` [net-next PATCH 6/7] net: ixgbe: add minimal parser details for ixgbe John Fastabend
2016-02-03 9:29 ` [net-next PATCH 7/7] net: ixgbe: add support for tc_u32 offload John Fastabend
2016-02-03 10:07 ` Amir Vadai"
2016-02-03 10:26 ` John Fastabend
2016-02-03 12:46 ` Jamal Hadi Salim [this message]
2016-02-03 19:02 ` Fastabend, John R
2016-02-09 11:30 ` Fastabend, John R
2016-02-04 7:30 ` Amir Vadai"
2016-02-04 8:23 ` Fastabend, John R
2016-02-04 12:12 ` Amir Vadai"
2016-02-09 11:27 ` Fastabend, John R
2016-02-03 10:11 ` [net-next PATCH 0/7] tc offload for cls_u32 on ixgbe Amir Vadai"
2016-02-03 10:21 ` John Fastabend
2016-02-03 10:31 ` Or Gerlitz
2016-02-03 12:21 ` Jamal Hadi Salim
2016-02-03 18:48 ` Fastabend, John R
2016-02-04 13:12 ` Jamal Hadi Salim
2016-02-09 11:24 ` Fastabend, John R
2016-02-09 12:20 ` Jamal Hadi Salim
2016-02-04 9:16 ` Jiri Pirko
2016-02-04 23:19 ` Pablo Neira Ayuso
2016-02-09 11:06 ` Fastabend, John R
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=56B1F689.5040609@mojatatu.com \
--to=jhs@mojatatu$(echo .)com \
--cc=amir@vadai$(echo .)me \
--cc=davem@davemloft$(echo .)net \
--cc=jeffrey.t.kirsher@intel$(echo .)com \
--cc=jiri@resnulli$(echo .)us \
--cc=john.fastabend@gmail$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=ogerlitz@mellanox$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox