When attaching XDP programs, userspace can set flags to request the attach
mode (generic/SKB mode, driver mode or hw offloaded mode). If no such flags
are requested, the kernel will attempt to attach in driver mode, and then
silently fall back to SKB mode if this fails.
The silent fallback is a major source of user confusion, as users will try
to load a program on a device without XDP support, and instead of an error
they will get the silent fallback behaviour, not notice, and then wonder
why performance is not what they were expecting.
In an attempt to combat this, let's switch all the samples to default to
explicitly requesting driver-mode attach. As part of this, ensure that all
the userspace utilities have a switch to enable SKB mode. For those that
have a switch to request driver mode, keep it but turn it into a no-op.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Link: https://lore.kernel.org/bpf/20191216110742.364456-1-toke@redhat.com
Commit 743e568c15 (samples/bpf: Add a "force" flag to XDP samples)
introduced the '-F' option but missed adding it to the usage() and the
'long_option' array.
Fixes: 743e568c15 (samples/bpf: Add a "force" flag to XDP samples)
Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191114162847.221770-2-andre.guedes@intel.com
Use Rx-only sockets for the rxdrop sample and Tx-only sockets for the
txpush sample in the xdpsock application. This so that we exercise and
show case these socket types too.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: William Tu <u9012063@gmail.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/1573148860-30254-5-git-send-email-magnus.karlsson@intel.com
Add support for the XDP_SHARED_UMEM mode to the xdpsock sample
application. As libbpf does not have a built in XDP program for this
mode, we use an explicitly loaded XDP program. This also serves as an
example on how to write your own XDP program that can route to an
AF_XDP socket.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: William Tu <u9012063@gmail.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/1573148860-30254-3-git-send-email-magnus.karlsson@intel.com
Preserve the offset of the address of the received descriptor, and include
it in the address set for the tx descriptor, so the kernel can correctly
locate the start of the packet data.
Fixes: 03895e63ff ("samples/bpf: add buffer recycling for unaligned chunks to xdpsock")
Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch modifies xdpsock to use mmap instead of posix_memalign. With
this change, we can use hugepages when running the application in unaligned
chunks mode. Using hugepages makes it more likely that we have physically
contiguous memory, which supports the unaligned chunk mode better.
Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch adds buffer recycling support for unaligned buffers. Since we
don't mask the addr to 2k at umem_reg in unaligned mode, we need to make
sure we give back the correct (original) addr to the fill queue. We achieve
this using the new descriptor format and associated masks. The new format
uses the upper 16-bits for the offset and the lower 48-bits for the addr.
Since we have a field for the offset, we no longer need to modify the
actual address. As such, all we have to do to get back the original address
is mask for the lower 48 bits (i.e. strip the offset and we get the address
on it's own).
Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch adds support for the unaligned chunks mode. The addition of the
unaligned chunks option will allow users to run the application with more
relaxed chunk placement in the XDP umem.
Unaligned chunks mode can be used with the '-u' or '--unaligned' command
line options.
Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit adds using the need_wakeup flag to the xdpsock sample
application. It is turned on by default as we think it is a feature
that seems to always produce a performance benefit, if the application
has been written taking advantage of it. It can be turned off in the
sample app by using the '-m' command line option.
The txpush and l2fwd sub applications have also been updated to
support poll() with multiple sockets.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The typical XDP memory scheme is one packet per page. Change the AF_XDP
frame size in libbpf to 4096, which is the page size on x86, to allow
libbpf to be used with the drivers with the packet-per-page scheme.
Add a command line option -f to xdpsock to allow to specify a custom
frame size.
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, header inclusion in each file is inconsistent.
For example, "libbpf.h" header is included as multiple ways.
#include "bpf/libbpf.h"
#include "libbpf.h"
Due to commit b552d33c80 ("samples/bpf: fix include path
in Makefile"), $(srctree)/tools/lib/bpf/ path had been included
during build, path "bpf/" in header isn't necessary anymore.
This commit removes path "bpf/" in header inclusion.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Compiling xdpsock_user.c with 4.8.5, I hit the following
compilation warning:
HOSTCC samples/bpf/xdpsock_user.o
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c: In function ‘main’:
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:449:6: warning: ‘idx_cq’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_cq, idx_fq;
^
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:606:7: warning: ‘idx_rx’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_rx, idx_tx = 0;
^
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:506:6: warning: ‘idx_rx’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_rx, idx_fq = 0;
As an example, the code pattern looks like:
u32 idx_cq;
...
ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq);
if (ret) {
...
}
... idx_fq ...
The compiler warns since it does not know whether &idx_fq is assigned
or not inside the library function xsk_ring_prod__reserve().
Let us assign an initial value 0 to such auto variables to silence
compiler warning.
Fixes: 248c7f9c0e ("samples/bpf: convert xdpsock to use libbpf for AF_XDP access")
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit converts the xdpsock sample application to use the AF_XDP
functions present in libbpf. This cuts down the size of it by nearly
300 lines of code.
The default ring sizes plus the batch size has been increased and the
size of the umem area has decreased. This so that the sample application
will provide higher throughput. Note also that the shared umem code
has been removed from the sample as this is not supported by libbpf
at this point in time.
Tested-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Check the program id within the signal handler on polling xdp samples
that were previously converted to libbpf usage. Avoid the situation of
unloading the program that was not attached by sample that is exiting.
Handle also the case where bpf_get_link_xdp_id didn't exit with an error
but the xdp program was not found on an interface.
Reported-by: Michal Papaj <michal.papaj@intel.com>
Reported-by: Jakub Spizewski <jakub.spizewski@intel.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Make xdp samples consistent with iproute2 behavior and set the
XDP_FLAGS_UPDATE_IF_NOEXIST by default when setting the xdp program on
interface. Provide an option for user to force the program loading,
which as a result will not include the mentioned flag in
bpf_set_link_xdp_fd call.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
- xsks_map size was fixed to 4, changed it MAX_SOCKS
- Remove redundant definition of MAX_SOCKS in xdpsock_user.c
- In dump_stats(), add NULL check for xsks[i]
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The -c/--copy -z/--zero-copy flags enforces either copy or zero-copy
mode.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Convert xdpsock_user.c to use libbpf instead of bpf_load.o.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Define u_smp_rmb() and u_smp_wmb() to respective barrier instructions.
This ensures the processor will order accesses to queue indices against
accesses to queue ring entries.
Signed-off-by: Brian Brooks <brian.brooks@linaro.org>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Sendmsg in the SKB path of AF_XDP can now return EBUSY when a packet
was discarded and completed by the driver. Just ignore this message
in the sample application.
Fixes: b4b8faa1de ("samples/bpf: sample application and documentation for AF_XDP sockets")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Reported-by: Pavel Odintsov <pavel@fastnetmon.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sure that XDP_SKB also uses the skb Tx path.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Here, the xdpsock sample application is adjusted to the new descriptor
format.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Adapt xdpsock to use the new getsockopt introduced in the previous
commit.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Clean up SPDX-License-Identifier and removing licensing leftovers.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
There are two files in the tree called libbpf.h which is becoming
problematic. Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h. Include bpf/bpf.h
directly instead.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is a sample application for AF_XDP sockets. The application
supports three different modes of operation: rxdrop, txonly and l2fwd.
To show-case a simple round-robin load-balancing between a set of
sockets in an xskmap, set the RR_LB compile time define option to 1 in
"xdpsock.h".
v2: The entries variable was calculated twice in {umem,xq}_nb_avail.
Co-authored-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>