<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/core/netdev-genl.c, branch v6.9</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>netdev: add queue stat for alloc failures</title>
<updated>2024-03-08T05:13:26+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2024-03-06T19:55:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=92f8b1f5ca0f157f564e75cef4c63641c172e0f1'/>
<id>92f8b1f5ca0f157f564e75cef4c63641c172e0f1</id>
<content type='text'>
Rx alloc failures are commonly counted by drivers.
Support reporting those via netdev-genl queue stats.

Acked-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Reviewed-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20240306195509.1502746-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rx alloc failures are commonly counted by drivers.
Support reporting those via netdev-genl queue stats.

Acked-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Reviewed-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20240306195509.1502746-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev: add per-queue statistics</title>
<updated>2024-03-08T05:13:25+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2024-03-06T19:55:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ab63a2387cb906d43b72a8effb611bbaecb2d0cd'/>
<id>ab63a2387cb906d43b72a8effb611bbaecb2d0cd</id>
<content type='text'>
The ethtool-nl family does a good job exposing various protocol
related and IEEE/IETF statistics which used to get dumped under
ethtool -S, with creative names. Queue stats don't have a netlink
API, yet, and remain a lion's share of ethtool -S output for new
drivers. Not only is that bad because the names differ driver to
driver but it's also bug-prone. Intuitively drivers try to report
only the stats for active queues, but querying ethtool stats
involves multiple system calls, and the number of stats is
read separately from the stats themselves. Worse still when user
space asks for values of the stats, it doesn't inform the kernel
how big the buffer is. If number of stats increases in the meantime
kernel will overflow user buffer.

Add a netlink API for dumping queue stats. Queue information is
exposed via the netdev-genl family, so add the stats there.
Support per-queue and sum-for-device dumps. Latter will be useful
when subsequent patches add more interesting common stats than
just bytes and packets.

The API does not currently distinguish between HW and SW stats.
The expectation is that the source of the stats will either not
matter much (good packets) or be obvious (skb alloc errors).

Acked-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Reviewed-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20240306195509.1502746-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The ethtool-nl family does a good job exposing various protocol
related and IEEE/IETF statistics which used to get dumped under
ethtool -S, with creative names. Queue stats don't have a netlink
API, yet, and remain a lion's share of ethtool -S output for new
drivers. Not only is that bad because the names differ driver to
driver but it's also bug-prone. Intuitively drivers try to report
only the stats for active queues, but querying ethtool stats
involves multiple system calls, and the number of stats is
read separately from the stats themselves. Worse still when user
space asks for values of the stats, it doesn't inform the kernel
how big the buffer is. If number of stats increases in the meantime
kernel will overflow user buffer.

Add a netlink API for dumping queue stats. Queue information is
exposed via the netdev-genl family, so add the stats there.
Support per-queue and sum-for-device dumps. Latter will be useful
when subsequent patches add more interesting common stats than
just bytes and packets.

The API does not currently distinguish between HW and SW stats.
The expectation is that the source of the stats will either not
matter much (good packets) or be obvious (skb alloc errors).

Acked-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Reviewed-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20240306195509.1502746-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev: let netlink core handle -EMSGSIZE errors</title>
<updated>2024-03-06T08:07:44+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2024-03-03T05:24:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0b11b1c5c320555483e8a94c44549db24c289987'/>
<id>0b11b1c5c320555483e8a94c44549db24c289987</id>
<content type='text'>
Previous change added -EMSGSIZE handling to af_netlink, we don't
have to hide these errors any longer.

Theoretically the error handling changes from:
 if (err == -EMSGSIZE)
to
 if (err == -EMSGSIZE &amp;&amp; skb-&gt;len)

everywhere, but in practice it doesn't matter.
All messages fit into NLMSG_GOODSIZE, so overflow of an empty
skb cannot happen.

Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Previous change added -EMSGSIZE handling to af_netlink, we don't
have to hide these errors any longer.

Theoretically the error handling changes from:
 if (err == -EMSGSIZE)
to
 if (err == -EMSGSIZE &amp;&amp; skb-&gt;len)

everywhere, but in practice it doesn't matter.
All messages fit into NLMSG_GOODSIZE, so overflow of an empty
skb cannot happen.

Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev-genl: Add PID for the NAPI thread</title>
<updated>2023-12-05T02:04:06+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:29:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=db4704f4e4dfce835e934609fca735a648ce26e8'/>
<id>db4704f4e4dfce835e934609fca735a648ce26e8</id>
<content type='text'>
In the threaded NAPI mode, expose the PID of the NAPI thread.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147335818.5260.10253384006102593087.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In the threaded NAPI mode, expose the PID of the NAPI thread.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147335818.5260.10253384006102593087.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Add NAPI IRQ support</title>
<updated>2023-12-05T02:04:06+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:29:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=26793bfb5d6072326d1465343e7cbf6156abca4f'/>
<id>26793bfb5d6072326d1465343e7cbf6156abca4f</id>
<content type='text'>
Add support to associate the interrupt vector number for a
NAPI instance.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147334728.5260.13221803396905901904.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add support to associate the interrupt vector number for a
NAPI instance.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147334728.5260.13221803396905901904.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev-genl: Add netlink framework functions for napi</title>
<updated>2023-12-05T02:04:05+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:28:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=27f91aaf49b3a50e5a02ad5fa27b7c453d029a72'/>
<id>27f91aaf49b3a50e5a02ad5fa27b7c453d029a72</id>
<content type='text'>
Implement the netdev netlink framework functions for
napi support. The netdev structure tracks all the napi
instances and napi fields. The napi instances and associated
parameters can be retrieved this way.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147333637.5260.14807433239805550815.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement the netdev netlink framework functions for
napi support. The netdev structure tracks all the napi
instances and napi fields. The napi instances and associated
parameters can be retrieved this way.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147333637.5260.14807433239805550815.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev-genl: spec: Extend netdev netlink spec in YAML for NAPI</title>
<updated>2023-12-05T02:04:05+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:28:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ff9991499fb53575c45eb92cd064bcd7141bb572'/>
<id>ff9991499fb53575c45eb92cd064bcd7141bb572</id>
<content type='text'>
Add support in netlink spec(netdev.yaml) for napi related information.
Add code generated from the spec.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147333119.5260.7050639053080529108.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add support in netlink spec(netdev.yaml) for napi related information.
Add code generated from the spec.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147333119.5260.7050639053080529108.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev-genl: Add netlink framework functions for queue</title>
<updated>2023-12-05T02:04:05+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:28:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6b6171db7fc8f7a6d0f0f0acb7aff16cecf14f42'/>
<id>6b6171db7fc8f7a6d0f0f0acb7aff16cecf14f42</id>
<content type='text'>
Implement the netdev netlink framework functions for
exposing queue information.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147332603.5260.7982559672617639065.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement the netdev netlink framework functions for
exposing queue information.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147332603.5260.7982559672617639065.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netdev-genl: spec: Extend netdev netlink spec in YAML for queue</title>
<updated>2023-12-05T02:04:05+00:00</updated>
<author>
<name>Amritha Nambiar</name>
<email>amritha.nambiar@intel.com</email>
</author>
<published>2023-12-01T23:28:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bc877956272f0521fef107838555817112a450dc'/>
<id>bc877956272f0521fef107838555817112a450dc</id>
<content type='text'>
Add support in netlink spec(netdev.yaml) for queue information.
Add code generated from the spec.

Note: The "queue-type" attribute takes values 0 and 1 for rx
and tx queue type respectively.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147330963.5260.2576294626647300472.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add support in netlink spec(netdev.yaml) for queue information.
Add code generated from the spec.

Note: The "queue-type" attribute takes values 0 and 1 for rx
and tx queue type respectively.

Signed-off-by: Amritha Nambiar &lt;amritha.nambiar@intel.com&gt;
Reviewed-by: Sridhar Samudrala &lt;sridhar.samudrala@intel.com&gt;
Link: https://lore.kernel.org/r/170147330963.5260.2576294626647300472.stgit@anambiarhost.jf.intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xsk: Add TX timestamp and TX checksum offload support</title>
<updated>2023-11-29T22:59:40+00:00</updated>
<author>
<name>Stanislav Fomichev</name>
<email>sdf@google.com</email>
</author>
<published>2023-11-27T19:03:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=48eb03dd26304c24f03bdbb9382e89c8564e71df'/>
<id>48eb03dd26304c24f03bdbb9382e89c8564e71df</id>
<content type='text'>
This change actually defines the (initial) metadata layout
that should be used by AF_XDP userspace (xsk_tx_metadata).
The first field is flags which requests appropriate offloads,
followed by the offload-specific fields. The supported per-device
offloads are exported via netlink (new xsk-flags).

The offloads themselves are still implemented in a bit of a
framework-y fashion that's left from my initial kfunc attempt.
I'm introducing new xsk_tx_metadata_ops which drivers are
supposed to implement. The drivers are also supposed
to call xsk_tx_metadata_request/xsk_tx_metadata_complete in
the right places. Since xsk_tx_metadata_{request,_complete}
are static inline, we don't incur any extra overhead doing
indirect calls.

The benefit of this scheme is as follows:
- keeps all metadata layout parsing away from driver code
- makes it easy to grep and see which drivers implement what
- don't need any extra flags to maintain to keep track of what
  offloads are implemented; if the callback is implemented - the offload
  is supported (used by netlink reporting code)

Two offloads are defined right now:
1. XDP_TXMD_FLAGS_CHECKSUM: skb-style csum_start+csum_offset
2. XDP_TXMD_FLAGS_TIMESTAMP: writes TX timestamp back into metadata
   area upon completion (tx_timestamp field)

XDP_TXMD_FLAGS_TIMESTAMP is also implemented for XDP_COPY mode: it writes
SW timestamp from the skb destructor (note I'm reusing hwtstamps to pass
metadata pointer).

The struct is forward-compatible and can be extended in the future
by appending more fields.

Reviewed-by: Song Yoong Siang &lt;yoong.siang.song@intel.com&gt;
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Link: https://lore.kernel.org/r/20231127190319.1190813-3-sdf@google.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This change actually defines the (initial) metadata layout
that should be used by AF_XDP userspace (xsk_tx_metadata).
The first field is flags which requests appropriate offloads,
followed by the offload-specific fields. The supported per-device
offloads are exported via netlink (new xsk-flags).

The offloads themselves are still implemented in a bit of a
framework-y fashion that's left from my initial kfunc attempt.
I'm introducing new xsk_tx_metadata_ops which drivers are
supposed to implement. The drivers are also supposed
to call xsk_tx_metadata_request/xsk_tx_metadata_complete in
the right places. Since xsk_tx_metadata_{request,_complete}
are static inline, we don't incur any extra overhead doing
indirect calls.

The benefit of this scheme is as follows:
- keeps all metadata layout parsing away from driver code
- makes it easy to grep and see which drivers implement what
- don't need any extra flags to maintain to keep track of what
  offloads are implemented; if the callback is implemented - the offload
  is supported (used by netlink reporting code)

Two offloads are defined right now:
1. XDP_TXMD_FLAGS_CHECKSUM: skb-style csum_start+csum_offset
2. XDP_TXMD_FLAGS_TIMESTAMP: writes TX timestamp back into metadata
   area upon completion (tx_timestamp field)

XDP_TXMD_FLAGS_TIMESTAMP is also implemented for XDP_COPY mode: it writes
SW timestamp from the skb destructor (note I'm reusing hwtstamps to pass
metadata pointer).

The struct is forward-compatible and can be extended in the future
by appending more fields.

Reviewed-by: Song Yoong Siang &lt;yoong.siang.song@intel.com&gt;
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Link: https://lore.kernel.org/r/20231127190319.1190813-3-sdf@google.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
