On 2/11/2022 9:26 AM, Loftus, Ciara wrote:
On 2/10/2022 5:47 PM, Loftus, Ciara wrote:
Subject: Re: [PATCH v4] net/af_xdp: re-enable secondary process
support
On 2/10/2022 3:40 PM, Loftus, Ciara wrote:
Subject: Re: [PATCH v4] net/af_xdp: re-enable secondary process
support
On 2/9/2022 9:48 AM, Ciara Loftus wrote:
Secondary process support had been disabled for the AF_XDP PMD
because
there was no logic in place to share the AF_XDP socket file
descriptors
between the processes. This commit introduces this logic using the
IPC
APIs.
Rx and Tx are disabled in the secondary process due to memory
mapping
of
the AF_XDP rings being assigned by the kernel in the primary
process
only.
However other operations including retrieval of stats are permitted.
Signed-off-by: Ciara Loftus <ciara.lof...@intel.com>
Hi Ciara,
When I tried to test the patch getting following error [1], it doesn't
look
related to this patch but can you help to fix the issue, thanks.
[1]
libxdp: Couldn't find a BPF file with name xsk_def_xdp_prog.o
xsk_configure(): Failed to create xsk socket.
eth_rx_queue_setup(): Failed to configure xdp socket
Fail to configure port 2 rx queues
EAL: Error - exiting with code: 1
Hi Ferruh,
This file should be generated when libxdp is compiled.
Mine is located @ /usr/local/lib/bpf/xsk_def_xdp_prog.o
Can you check if that file is there for you? It could be in
/usr/local/lib64/bpf/ on your machine.
What kernel are you running on?
It is in: /usr/local/lib64/bpf/xsk_def_xdp_prog.o
I had to compile libxdp from source because OS package version was old
to work with af_xdp.
Is something required to point location of this file to af_xdp PMD?
I run kernel:
5.15.16-200.fc35.x86_64
I read through the libxdp code to figure out what happens when
searching
for the file:
https://github.com/xdp-project/xdp-
tools/blob/v1.2.2/lib/libxdp/libxdp.c#L1055
secure_getenv(XDP_OBJECT_ENVVAR) is called which according to the
README "defaults to /usr/lib/bpf (or /usr/lib64/bpf on systems using a split
library path)".
If that fails, BPF_OBJECT_PATH will be searched, which points to
/usr/lib/bpf
I discovered that on my system the getenv() call fails, but the file is
eventually found because luckily BPF_OBJECT_PATH points to the
appropriate place for me (lib):
https://github.com/xdp-project/xdp-tools/blob/v1.2.2/lib/util/util.h#L24
I suspect the same failure is happening for you, but since
BPF_OBJECT_PATH points to lib and not lib64, the file is not found.
As a temporary measure can you create a symlink in /usr/local/lib/bpf/ to
point to /usr/local/lib/bpf/xsk_def_xdp_prog.o
I will investigate the libxdp issue further. Maybe a change is needed in
the
library. If a change or setup recommendation is needed in DPDK I will
create a
patch.
I don't have XDP_OBJECT_ENVVAR or BPF_OBJECT_PATH environment
variables set,
if they should be we should document them.
When I created '/usr/local/lib/bpf/' link, the BPF file found.
This should be clarified/documented for users.
Ok. Ideally we shouldn't have to create the symlink. I will look for a better
solution and submit a patch.
The symlink might be a temporary solution if another solution is not found.
Can you please try setting the environment variable
LIBXDP_OBJECT_PATH=/usr/local/lib64/bpf/
And see if your test works without the symlink?
This worked for me and the getenv succeeded.
If it works for you too, I'll create a patch for the docs instructing users to
do the same.
I confirm it works, and +1 to document it.
btw, when this environment variable is not set (and no symlink), af_xdp fails
and testpmd crashes. I think af_xdp failure shouldn't cause a crash in testpmd,
most probably some error checks are needed in the af_xdp driver.
Thanks,
Ciara
And still observing following two:
1) I don't know what following log means:
Configuring Port 2 (socket 0)
libbpf: elf: skipping unrecognized data section(7) .xdp_run_config
libbpf: elf: skipping unrecognized data section(8) xdp_metadata
libxdp: XDP flag not supported by libxdp.
libbpf: elf: skipping unrecognized data section(8) xdp_metadata
libbpf: elf: skipping unrecognized data section(8) xdp_metadata
I reported this and a patch was submitted to libbpf to demote those logs:
https://www.spinics.net/lists/bpf/msg49140.html
It looks like the patch never made it. I'll chase it up.
Anyway, the logs can be ignored as they are not errors.
2) When I try to create two af_xdp interface, I only got one:
"--vdev net_af_xdp,iface=enp24s0f1 --vdev net_af_xdp,iface=enp24s0f0"
This is also expected as you haven't given each vdev a unique name. Try:
"--vdev net_af_xdp0,iface=enp24s0f1 --vdev net_af_xdp1,iface=enp24s0f0"
Thank you for the testing.
Ciara
Thanks,
ferruh
