RE: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc action

2017-02-05 Thread Yotam Gigi 
>-Original Message-
>From: Florian Fainelli [mailto:f.faine...@gmail.com]
>Sent: Sunday, February 05, 2017 10:55 PM
>To: Yotam Gigi <yot...@mellanox.com>; step...@networkplumber.org;
>netdev@vger.kernel.org; Jiri Pirko <j...@mellanox.com>; Elad Raz
><el...@mellanox.com>
>Subject: Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc 
>action
>
>Le 02/05/17 à 12:22, Yotam Gigi a écrit :
>>> -Original Message-
>>> From: Florian Fainelli [mailto:f.faine...@gmail.com]
>>> Sent: Sunday, February 05, 2017 8:37 PM
>>> To: Yotam Gigi <yot...@mellanox.com>; step...@networkplumber.org;
>>> netdev@vger.kernel.org; Jiri Pirko <j...@mellanox.com>; Elad Raz
>>> <el...@mellanox.com>
>>> Subject: Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc
>action
>>>
>>> On 02/04/2017 11:58 PM, Yotam Gigi wrote:
>>>> The sample tc action allows sampling packets matching a classifier. It
>>>> peeks randomly packets, and samples them using the psample netlink
>>>> channel. The user can specify the psample group, which the packet will be
>>>> sampled to, the sampling rate and the packet truncation (to save
>>>> kernel-user traffic).
>>>>
>>>> The sampled packets contain informative metadata, for example, the input
>>>> interface and the original packet length.
>>>>
>>>> The action syntax:
>>>> tc filter add [...] \
>>>>action sample rate  group  [trunc ]
>>>>[...]
>>>>
>>>> Where:
>>>>   RATE := The sampling rate which is the ratio of packets observed at the
>>>>  data source to the samples generated
>>>>   GROUP := the psample module sampling group
>>>>   SIZE := optional truncation size
>>>>
>>>> An example for a common usecase of the sample tc action: to sample ingress
>>>> traffic from interface eth1, one may use the commands:
>>>>
>>>> tc qdisc add dev eth1 handle : ingress
>>>>
>>>> tc filter add dev eth1 parent : \
>>>>matchall action sample rate 12 group 4
>>>>
>>>> Where the first command adds an ingress qdisc and the second starts
>>>> sampling randomly with an average of one sampled packet per 12 packets
>>>> on dev eth1 to psample group 4.
>>>
>>> The group argument seems to be mandatory from looking at the code, but
>>> what if just wanted to have a port mirroring between, say sw0p1 and
>>> sw0p2 with the sample rate specified instead (without using the psample
>>> netlink channel at all)? Could we make this group an optional argument
>>> instead?
>>
>> The kernel action currently don't support it, and I am not sure it should.
>>
>> If I understand you correctly, you want to make the sample action identical
>> to mirred-mirror, only with random behavior. This can be done using the
>> matchall and mirred action, plus the 'random' gact keyword.
>
>It sounds like we can indeed, with random determ and using the VAL
>argument we should be able to configure the capture divider; thanks!

You're welcome. It took me some time to find that keyword too :)

>
>>
>> The sample action attaches some metadata in addition to the original packet
>> data, and that cannot be achieved by mirroring the packets, thus making it
>> unusable for our usecase. In the former version we attached the metadata
>> using the IFE protocol, but we decided to use a dedicated netlink channel
>> instead.
>
>Yeah I see that now, thanks for the explanation!
>--
>Florian

Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc action

2017-02-05 Thread Florian Fainelli 
Le 02/05/17 à 12:22, Yotam Gigi a écrit :
>> -Original Message-
>> From: Florian Fainelli [mailto:f.faine...@gmail.com]
>> Sent: Sunday, February 05, 2017 8:37 PM
>> To: Yotam Gigi <yot...@mellanox.com>; step...@networkplumber.org;
>> netdev@vger.kernel.org; Jiri Pirko <j...@mellanox.com>; Elad Raz
>> <el...@mellanox.com>
>> Subject: Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc 
>> action
>>
>> On 02/04/2017 11:58 PM, Yotam Gigi wrote:
>>> The sample tc action allows sampling packets matching a classifier. It
>>> peeks randomly packets, and samples them using the psample netlink
>>> channel. The user can specify the psample group, which the packet will be
>>> sampled to, the sampling rate and the packet truncation (to save
>>> kernel-user traffic).
>>>
>>> The sampled packets contain informative metadata, for example, the input
>>> interface and the original packet length.
>>>
>>> The action syntax:
>>> tc filter add [...] \
>>> action sample rate  group  [trunc ]
>>> [...]
>>>
>>> Where:
>>>   RATE := The sampling rate which is the ratio of packets observed at the
>>>   data source to the samples generated
>>>   GROUP := the psample module sampling group
>>>   SIZE := optional truncation size
>>>
>>> An example for a common usecase of the sample tc action: to sample ingress
>>> traffic from interface eth1, one may use the commands:
>>>
>>> tc qdisc add dev eth1 handle : ingress
>>>
>>> tc filter add dev eth1 parent : \
>>>matchall action sample rate 12 group 4
>>>
>>> Where the first command adds an ingress qdisc and the second starts
>>> sampling randomly with an average of one sampled packet per 12 packets
>>> on dev eth1 to psample group 4.
>>
>> The group argument seems to be mandatory from looking at the code, but
>> what if just wanted to have a port mirroring between, say sw0p1 and
>> sw0p2 with the sample rate specified instead (without using the psample
>> netlink channel at all)? Could we make this group an optional argument
>> instead?
> 
> The kernel action currently don't support it, and I am not sure it should.
> 
> If I understand you correctly, you want to make the sample action identical
> to mirred-mirror, only with random behavior. This can be done using the 
> matchall and mirred action, plus the 'random' gact keyword.

It sounds like we can indeed, with random determ and using the VAL
argument we should be able to configure the capture divider; thanks!

> 
> The sample action attaches some metadata in addition to the original packet
> data, and that cannot be achieved by mirroring the packets, thus making it
> unusable for our usecase. In the former version we attached the metadata
> using the IFE protocol, but we decided to use a dedicated netlink channel 
> instead.

Yeah I see that now, thanks for the explanation!
-- 
Florian

RE: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc action

2017-02-05 Thread Yotam Gigi 
>-Original Message-
>From: Florian Fainelli [mailto:f.faine...@gmail.com]
>Sent: Sunday, February 05, 2017 8:37 PM
>To: Yotam Gigi <yot...@mellanox.com>; step...@networkplumber.org;
>netdev@vger.kernel.org; Jiri Pirko <j...@mellanox.com>; Elad Raz
><el...@mellanox.com>
>Subject: Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc 
>action
>
>On 02/04/2017 11:58 PM, Yotam Gigi wrote:
>> The sample tc action allows sampling packets matching a classifier. It
>> peeks randomly packets, and samples them using the psample netlink
>> channel. The user can specify the psample group, which the packet will be
>> sampled to, the sampling rate and the packet truncation (to save
>> kernel-user traffic).
>>
>> The sampled packets contain informative metadata, for example, the input
>> interface and the original packet length.
>>
>> The action syntax:
>> tc filter add [...] \
>>  action sample rate  group  [trunc ]
>>  [...]
>>
>> Where:
>>   RATE := The sampling rate which is the ratio of packets observed at the
>>data source to the samples generated
>>   GROUP := the psample module sampling group
>>   SIZE := optional truncation size
>>
>> An example for a common usecase of the sample tc action: to sample ingress
>> traffic from interface eth1, one may use the commands:
>>
>> tc qdisc add dev eth1 handle : ingress
>>
>> tc filter add dev eth1 parent : \
>>matchall action sample rate 12 group 4
>>
>> Where the first command adds an ingress qdisc and the second starts
>> sampling randomly with an average of one sampled packet per 12 packets
>> on dev eth1 to psample group 4.
>
>The group argument seems to be mandatory from looking at the code, but
>what if just wanted to have a port mirroring between, say sw0p1 and
>sw0p2 with the sample rate specified instead (without using the psample
>netlink channel at all)? Could we make this group an optional argument
>instead?

The kernel action currently don't support it, and I am not sure it should.

If I understand you correctly, you want to make the sample action identical
to mirred-mirror, only with random behavior. This can be done using the 
matchall and mirred action, plus the 'random' gact keyword. 

The sample action attaches some metadata in addition to the original packet
data, and that cannot be achieved by mirroring the packets, thus making it
unusable for our usecase. In the former version we attached the metadata
using the IFE protocol, but we decided to use a dedicated netlink channel 
instead.

>
>Thanks!
>--
>Florian

Re: [PATCH iproute2/net-next 1/3] tc: Add support for the sample tc action

2017-02-05 Thread Florian Fainelli 
On 02/04/2017 11:58 PM, Yotam Gigi wrote:
> The sample tc action allows sampling packets matching a classifier. It
> peeks randomly packets, and samples them using the psample netlink
> channel. The user can specify the psample group, which the packet will be
> sampled to, the sampling rate and the packet truncation (to save
> kernel-user traffic).
> 
> The sampled packets contain informative metadata, for example, the input
> interface and the original packet length.
> 
> The action syntax:
> tc filter add [...] \
>   action sample rate  group  [trunc ]
>   [...]
> 
> Where:
>   RATE := The sampling rate which is the ratio of packets observed at the
> data source to the samples generated
>   GROUP := the psample module sampling group
>   SIZE := optional truncation size
> 
> An example for a common usecase of the sample tc action: to sample ingress
> traffic from interface eth1, one may use the commands:
> 
> tc qdisc add dev eth1 handle : ingress
> 
> tc filter add dev eth1 parent : \
>matchall action sample rate 12 group 4
> 
> Where the first command adds an ingress qdisc and the second starts
> sampling randomly with an average of one sampled packet per 12 packets
> on dev eth1 to psample group 4.

The group argument seems to be mandatory from looking at the code, but
what if just wanted to have a port mirroring between, say sw0p1 and
sw0p2 with the sample rate specified instead (without using the psample
netlink channel at all)? Could we make this group an optional argument
instead?

Thanks!
-- 
Florian

[PATCH iproute2/net-next 1/3] tc: Add support for the sample tc action

2017-02-04 Thread Yotam Gigi 
The sample tc action allows sampling packets matching a classifier. It
peeks randomly packets, and samples them using the psample netlink
channel. The user can specify the psample group, which the packet will be
sampled to, the sampling rate and the packet truncation (to save
kernel-user traffic).

The sampled packets contain informative metadata, for example, the input
interface and the original packet length.

The action syntax:
tc filter add [...] \
action sample rate  group  [trunc ]
[...]

Where:
  RATE := The sampling rate which is the ratio of packets observed at the
  data source to the samples generated
  GROUP := the psample module sampling group
  SIZE := optional truncation size

An example for a common usecase of the sample tc action: to sample ingress
traffic from interface eth1, one may use the commands:

tc qdisc add dev eth1 handle : ingress

tc filter add dev eth1 parent : \
   matchall action sample rate 12 group 4

Where the first command adds an ingress qdisc and the second starts
sampling randomly with an average of one sampled packet per 12 packets
on dev eth1 to psample group 4.

Reviewed-by: Jiri Pirko 
Signed-off-by: Yotam Gigi 
---
 bash-completion/tc   |   8 +-
 include/linux/tc_act/tc_sample.h |  26 ++
 tc/Makefile  |   1 +
 tc/m_sample.c| 186 +++
 4 files changed, 220 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/tc_act/tc_sample.h
 create mode 100644 tc/m_sample.c

diff --git a/bash-completion/tc b/bash-completion/tc
index 79dd5fc..ed2796d 100644
--- a/bash-completion/tc
+++ b/bash-completion/tc
@@ -430,6 +430,12 @@ _tc_action_options()
 _tc_once_attr 'index dev'
 return 0
 ;;
+sample)
+_tc_once_attr 'rate'
+_tc_once_attr 'trunc'
+_tc_once_attr 'group'
+return 0
+;;
 gact)
 _tc_one_of_list 'reclassify drop continue pass'
 _tc_once_attr 'random'
@@ -671,7 +677,7 @@ _tc()
 action)
 case $subcmd in
 add|change|replace)
-local action acwd ACTION_KIND=' gact mirred bpf '
+local action acwd ACTION_KIND=' gact mirred bpf sample '
 for ((acwd=$subcword; acwd < ${#words[@]}-1; acwd++)); do
 if [[ $ACTION_KIND =~ ' '${words[acwd]}' ' ]]; then
 action=${words[acwd]}
diff --git a/include/linux/tc_act/tc_sample.h b/include/linux/tc_act/tc_sample.h
new file mode 100644
index 000..edc9058
--- /dev/null
+++ b/include/linux/tc_act/tc_sample.h
@@ -0,0 +1,26 @@
+#ifndef __LINUX_TC_SAMPLE_H
+#define __LINUX_TC_SAMPLE_H
+
+#include 
+#include 
+#include 
+
+#define TCA_ACT_SAMPLE 26
+
+struct tc_sample {
+   tc_gen;
+};
+
+enum {
+   TCA_SAMPLE_UNSPEC,
+   TCA_SAMPLE_TM,
+   TCA_SAMPLE_PARMS,
+   TCA_SAMPLE_RATE,
+   TCA_SAMPLE_TRUNC_SIZE,
+   TCA_SAMPLE_PSAMPLE_GROUP,
+   TCA_SAMPLE_PAD,
+   __TCA_SAMPLE_MAX
+};
+#define TCA_SAMPLE_MAX (__TCA_SAMPLE_MAX - 1)
+
+#endif
diff --git a/tc/Makefile b/tc/Makefile
index 7fd0c4a..6dd984f 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -51,6 +51,7 @@ TCMODULES += m_vlan.o
 TCMODULES += m_connmark.o
 TCMODULES += m_bpf.o
 TCMODULES += m_tunnel_key.o
+TCMODULES += m_sample.o
 TCMODULES += p_ip.o
 TCMODULES += p_icmp.o
 TCMODULES += p_tcp.o
diff --git a/tc/m_sample.c b/tc/m_sample.c
new file mode 100644
index 000..9291109
--- /dev/null
+++ b/tc/m_sample.c
@@ -0,0 +1,186 @@
+/*
+ * m_sample.c  ingress/egress packet sampling module
+ *
+ * This program is free software; you can distribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors:Yotam Gigi 
+ *
+ */
+
+#include 
+#include "utils.h"
+#include "tc_util.h"
+#include "tc_common.h"
+#include 
+
+static void explain(void)
+{
+   fprintf(stderr, "Usage: sample SAMPLE_CONF\n");
+   fprintf(stderr, "where:\n");
+   fprintf(stderr, "\tSAMPLE_CONF := SAMPLE_PARAMS | SAMPLE_INDEX\n");
+   fprintf(stderr, "\tSAMPLE_PARAMS := rate RATE group GROUP [trunc SIZE] 
[SAMPLE_INDEX]\n");
+   fprintf(stderr, "\tSAMPLE_INDEX := index INDEX\n");
+   fprintf(stderr, "\tRATE := The ratio of packets observed at the data 
source to the samples generated.\n");
+   fprintf(stderr, "\tGROUP := the psample sampling group\n");
+   fprintf(stderr, "\tSIZE := the truncation size\n");
+   fprintf(stderr, "\tINDEX := integer index of the sample action\n");
+}
+
+static void usage(void)
+{
+   explain();
+   exit(-1);
+}
+
+static int