Commit Graph

522 Commits

Author SHA1 Message Date
Daniel T. Lee
763af200d6 samples: bpf: Refactor ibumad program with libbpf
This commit refactors the existing ibumad program with libbpf bpf
loader. Attach/detach of Tracepoint bpf programs has been managed
with the generic bpf_program__attach() and bpf_link__destroy() from
the libbpf.

Also, instead of using the previous BPF MAP definition, this commit
refactors ibumad MAP definition with the new BTF-defined MAP format.

To verify that this bpf program works without an infiniband device,
try loading ib_umad kernel module and test the program as follows:

    # modprobe ib_umad
    # ./ibumad

Moreover, TRACE_HELPERS has been removed from the Makefile since it is
not used on this program.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-5-danieltimlee@gmail.com
2020-11-26 19:33:36 -08:00
Daniel T. Lee
4fe6641526 samples: bpf: Refactor task_fd_query program with libbpf
This commit refactors the existing kprobe program with libbpf bpf
loader. To attach bpf program, this uses generic bpf_program__attach()
approach rather than using bpf_load's load_bpf_file().

To attach bpf to perf_event, instead of using previous ioctl method,
this commit uses bpf_program__attach_perf_event since it manages the
enable of perf_event and attach of BPF programs to it, which is much
more intuitive way to achieve.

Also, explicit close(fd) has been removed since event will be closed
inside bpf_link__destroy() automatically.

Furthermore, to prevent conflict of same named uprobe events, O_TRUNC
flag has been used to clear 'uprobe_events' interface.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-4-danieltimlee@gmail.com
2020-11-26 19:33:35 -08:00
Daniel T. Lee
d89af13c92 samples: bpf: Refactor test_cgrp2_sock2 program with libbpf
This commit refactors the existing cgroup program with libbpf bpf
loader. The original test_cgrp2_sock2 has keeped the bpf program
attached to the cgroup hierarchy even after the exit of user program.
To implement the same functionality with libbpf, this commit uses the
BPF_LINK_PINNING to pin the link attachment even after it is closed.

Since this uses LINK instead of ATTACH, detach of bpf program from
cgroup with 'test_cgrp2_sock' is not used anymore.

The code to mount the bpf was added to the .sh file in case the bpff
was not mounted on /sys/fs/bpf. Additionally, to fix the problem that
shell script cannot find the binary object from the current path,
relative path './' has been added in front of binary.

Fixes: 554ae6e792 ("samples/bpf: add userspace example for prohibiting sockets")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-3-danieltimlee@gmail.com
2020-11-26 19:33:35 -08:00
Daniel T. Lee
c5815ac7e2 samples: bpf: Refactor hbm program with libbpf
This commit refactors the existing cgroup programs with libbpf
bpf loader. Since bpf_program__attach doesn't support cgroup program
attachment, this explicitly attaches cgroup bpf program with
bpf_program__attach_cgroup(bpf_prog, cg1).

Also, to change attach_type of bpf program, this uses libbpf's
bpf_program__set_expected_attach_type helper to switch EGRESS to
INGRESS. To keep bpf program attached to the cgroup hierarchy even
after the exit, this commit uses the BPF_LINK_PINNING to pin the link
attachment even after it is closed.

Besides, this program was broken due to the typo of BPF MAP definition.
But this commit solves the problem by fixing this from 'queue_stats' map
struct hvm_queue_stats -> hbm_queue_stats.

Fixes: 36b5d47113 ("selftests/bpf: samples/bpf: Split off legacy stuff from bpf_helpers.h")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-2-danieltimlee@gmail.com
2020-11-26 19:33:35 -08:00
Magnus Karlsson
90da4b3208 samples/bpf: Increment Tx stats at sending
Increment the statistics over how many Tx packets have been sent at
the time of sending instead of at the time of completion. This as a
completion event means that the buffer has been sent AND returned to
user space. The packet always gets sent shortly after sendto() is
called. The kernel might, for performance reasons, decide to not
return every single buffer to user space immediately after sending,
for example, only after a batch of packets have been
transmitted. Incrementing the number of packets sent at completion,
will in that case be confusing as if you send a single packet, the
counter might show zero for a while even though the packet has been
transmitted.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/1605525167-14450-2-git-send-email-magnus.karlsson@gmail.com
2020-11-17 22:07:40 +01:00
Jakub Kicinski
07cbce2e46 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-11-14

1) Add BTF generation for kernel modules and extend BTF infra in kernel
   e.g. support for split BTF loading and validation, from Andrii Nakryiko.

2) Support for pointers beyond pkt_end to recognize LLVM generated patterns
   on inlined branch conditions, from Alexei Starovoitov.

3) Implements bpf_local_storage for task_struct for BPF LSM, from KP Singh.

4) Enable FENTRY/FEXIT/RAW_TP tracing program to use the bpf_sk_storage
   infra, from Martin KaFai Lau.

5) Add XDP bulk APIs that introduce a defer/flush mechanism to optimize the
   XDP_REDIRECT path, from Lorenzo Bianconi.

6) Fix a potential (although rather theoretical) deadlock of hashtab in NMI
   context, from Song Liu.

7) Fixes for cross and out-of-tree build of bpftool and runqslower allowing build
   for different target archs on same source tree, from Jean-Philippe Brucker.

8) Fix error path in htab_map_alloc() triggered from syzbot, from Eric Dumazet.

9) Move functionality from test_tcpbpf_user into the test_progs framework so it
   can run in BPF CI, from Alexander Duyck.

10) Lift hashtab key_size limit to be larger than MAX_BPF_STACK, from Florian Lehner.

Note that for the fix from Song we have seen a sparse report on context
imbalance which requires changes in sparse itself for proper annotation
detection where this is currently being discussed on linux-sparse among
developers [0]. Once we have more clarification/guidance after their fix,
Song will follow-up.

  [0] https://lore.kernel.org/linux-sparse/CAHk-=wh4bx8A8dHnX612MsDO13st6uzAz1mJ1PaHHVevJx_ZCw@mail.gmail.com/T/
      https://lore.kernel.org/linux-sparse/20201109221345.uklbp3lzgq6g42zb@ltop.local/T/

* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (66 commits)
  net: mlx5: Add xdp tx return bulking support
  net: mvpp2: Add xdp tx return bulking support
  net: mvneta: Add xdp tx return bulking support
  net: page_pool: Add bulk support for ptr_ring
  net: xdp: Introduce bulking for xdp tx return path
  bpf: Expose bpf_d_path helper to sleepable LSM hooks
  bpf: Augment the set of sleepable LSM hooks
  bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP
  bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP
  bpf: Rename some functions in bpf_sk_storage
  bpf: Folding omem_charge() into sk_storage_charge()
  selftests/bpf: Add asm tests for pkt vs pkt_end comparison.
  selftests/bpf: Add skb_pkt_end test
  bpf: Support for pointers beyond pkt_end.
  tools/bpf: Always run the *-clean recipes
  tools/bpf: Add bootstrap/ to .gitignore
  bpf: Fix NULL dereference in bpf_task_storage
  tools/bpftool: Fix build slowdown
  tools/runqslower: Build bpftool using HOSTCC
  tools/runqslower: Enable out-of-tree build
  ...
====================

Link: https://lore.kernel.org/r/20201114020819.29584-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-14 09:13:41 -08:00
Hangbin Liu
e2215b0555 samples/bpf: Remove unused test_ipip.sh
The tcbpf2_kern.o and related kernel sections are moved to bpf
selftest folder since b05cd74043 ("samples/bpf: remove the bpf tunnel
testsuite."). Remove this one as well.

Fixes: b05cd74043 ("samples/bpf: remove the bpf tunnel testsuite.")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201110015013.1570716-3-liuhangbin@gmail.com
2020-11-10 15:37:45 -08:00
Menglong Dong
a10b4f9610 samples/bpf: Remove duplicate include in hbm
The 'bpf/bpf.h' include in 'samples/bpf/hbm.c' is duplicated.

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/1604654034-52821-1-git-send-email-dong.menglong@zte.com.cn
2020-11-10 00:01:31 +01:00
Toke Høiland-Jørgensen
c66dca98a2 samples/bpf: Set rlimit for memlock to infinity in all samples
The memlock rlimit is a notorious source of failure for BPF programs. Most
of the samples just set it to infinity, but a few used a lower limit. The
problem with unconditionally setting a lower limit is that this will also
override the limit if the system-wide setting is *higher* than the limit
being set, which can lead to failures on systems that lock a lot of memory,
but set 'ulimit -l' to unlimited before running a sample.

One fix for this is to only conditionally set the limit if the current
limit is lower, but it is simpler to just unify all the samples and have
them all set the limit to infinity.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20201026233623.91728-1-toke@redhat.com
2020-10-27 22:46:17 +01:00
Daniel Borkmann
3652c9a1b1 bpf, libbpf: Guard bpf inline asm from bpf_tail_call_static
Yaniv reported a compilation error after pulling latest libbpf:

  [...]
  ../libbpf/src/root/usr/include/bpf/bpf_helpers.h:99:10: error:
  unknown register name 'r0' in asm
                     : "r0", "r1", "r2", "r3", "r4", "r5");
  [...]

The issue got triggered given Yaniv was compiling tracing programs with native
target (e.g. x86) instead of BPF target, hence no BTF generated vmlinux.h nor
CO-RE used, and later llc with -march=bpf was invoked to compile from LLVM IR
to BPF object file. Given that clang was expecting x86 inline asm and not BPF
one the error complained that these regs don't exist on the former.

Guard bpf_tail_call_static() with defined(__bpf__) where BPF inline asm is valid
to use. BPF tracing programs on more modern kernels use BPF target anyway and
thus the bpf_tail_call_static() function will be available for them. BPF inline
asm is supported since clang 7 (clang <= 6 otherwise throws same above error),
and __bpf_unreachable() since clang 8, therefore include the latter condition
in order to prevent compilation errors for older clang versions. Given even an
old Ubuntu 18.04 LTS has official LLVM packages all the way up to llvm-10, I did
not bother to special case the __bpf_unreachable() inside bpf_tail_call_static()
further.

Also, undo the sockex3_kern's use of bpf_tail_call_static() sample given they
still have the old hacky way to even compile networking progs with native instead
of BPF target so bpf_tail_call_static() won't be defined there anymore.

Fixes: 0e9f6841f6 ("bpf, libbpf: Add bpf_tail_call_static helper for bpf programs")
Reported-by: Yaniv Agman <yanivagman@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Tested-by: Yaniv Agman <yanivagman@gmail.com>
Link: https://lore.kernel.org/bpf/CAMy7=ZUk08w5Gc2Z-EKi4JFtuUCaZYmE4yzhJjrExXpYKR4L8w@mail.gmail.com
Link: https://lore.kernel.org/bpf/20201021203257.26223-1-daniel@iogearbox.net
2020-10-22 01:46:52 +02:00
Daniel T. Lee
321f632450 samples: bpf: Refactor XDP kern program maps with BTF-defined map
Most of the samples were converted to use the new BTF-defined MAP as
they moved to libbpf, but some of the samples were missing.

Instead of using the previous BPF MAP definition, this commit refactors
xdp_monitor and xdp_sample_pkts_kern MAP definition with the new
BTF-defined MAP format.

Also, this commit removes the max_entries attribute at PERF_EVENT_ARRAY
map type. The libbpf's bpf_object__create_map() will automatically
set max_entries to the maximum configured number of CPUs on the host.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201010181734.1109-4-danieltimlee@gmail.com
2020-10-11 12:14:36 -07:00
Daniel T. Lee
151936bf51 samples: bpf: Replace attach_tracepoint() to attach() in xdp_redirect_cpu
>From commit d7a18ea7e8 ("libbpf: Add generic bpf_program__attach()"),
for some BPF programs, it is now possible to attach BPF programs
with __attach() instead of explicitly calling __attach_<type>().

This commit refactors the __attach_tracepoint() with libbpf's generic
__attach() method. In addition, this refactors the logic of setting
the map FD to simplify the code. Also, the missing removal of
bpf_load.o in Makefile has been fixed.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201010181734.1109-3-danieltimlee@gmail.com
2020-10-11 12:14:36 -07:00
Daniel T. Lee
8ac91df6de samples: bpf: Refactor xdp_monitor with libbpf
To avoid confusion caused by the increasing fragmentation of the BPF
Loader program, this commit would like to change to the libbpf loader
instead of using the bpf_load.

Thanks to libbpf's bpf_link interface, managing the tracepoint BPF
program is much easier. bpf_program__attach_tracepoint manages the
enable of tracepoint event and attach of BPF programs to it with a
single interface bpf_link, so there is no need to manage event_fd and
prog_fd separately.

This commit refactors xdp_monitor with using this libbpf API, and the
bpf_load is removed and migrated to libbpf.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201010181734.1109-2-danieltimlee@gmail.com
2020-10-11 12:14:36 -07:00
Ciara Loftus
67ed375530 samples: bpf: Driver interrupt statistics in xdpsock
Add an option to count the number of interrupts generated per second and
total number of interrupts during the lifetime of the application for a
given interface. This information is extracted from /proc/interrupts. Since
there is no naming convention across drivers, the user must provide the
string which is specific to their interface in the /proc/interrupts file on
the command line.

Usage:

./xdpsock ... -I <irq_str>

eg. for queue 0 of i40e device eth0:

./xdpsock ... -I i40e-eth0-TxRx-0

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201002133612.31536-3-ciara.loftus@intel.com
2020-10-06 11:46:50 -07:00
Ciara Loftus
60dc609dbd samples: bpf: Count syscalls in xdpsock
Categorise and record syscalls issued in the xdpsock sample app. The
categories recorded are:

  rx_empty_polls:    polls when the rx ring is empty
  fill_fail_polls:   polls when failed to get addr from fill ring
  copy_tx_sendtos:   sendtos issued for tx when copy mode enabled
  tx_wakeup_sendtos: sendtos issued when tx ring needs waking up
  opt_polls:         polls issued since the '-p' flag is set

Print the stats using '-a' on the xdpsock command line.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201002133612.31536-2-ciara.loftus@intel.com
2020-10-06 11:46:50 -07:00
Ciara Loftus
2e8806f032 samples: bpf: Split xdpsock stats into new struct
New statistics will be added in future commits. In preparation for this,
let's split out the existing statistics into their own struct.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201002133612.31536-1-ciara.loftus@intel.com
2020-10-06 11:46:50 -07:00
Yonghong Song
544d6adf3c samples/bpf: Fix a compilation error with fallthrough marking
Compiling samples/bpf hits an error related to fallthrough marking.
    ...
    CC  samples/bpf/hbm.o
  samples/bpf/hbm.c: In function ‘main’:
  samples/bpf/hbm.c:486:4: error: ‘fallthrough’ undeclared (first use in this function)
      fallthrough;
      ^~~~~~~~~~~

The "fallthrough" is not defined under tools/include directory.
Rather, it is "__fallthrough" is defined in linux/compiler.h.
Including "linux/compiler.h" and using "__fallthrough" fixed the issue.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201006043427.1891805-1-yhs@fb.com
2020-10-06 11:45:03 -07:00
Yonghong Song
9618bde489 samples/bpf: Change Makefile to cope with latest llvm
With latest llvm trunk, bpf programs under samples/bpf
directory, if using CORE, may experience the following
errors:

LLVM ERROR: Cannot select: intrinsic %llvm.preserve.struct.access.index
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
Stack dump:
0.      Program arguments: llc -march=bpf -filetype=obj -o samples/bpf/test_probe_write_user_kern.o
1.      Running pass 'Function Pass Manager' on module '<stdin>'.
2.      Running pass 'BPF DAG->DAG Pattern Instruction Selection' on function '@bpf_prog1'
 #0 0x000000000183c26c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int)
    (/data/users/yhs/work/llvm-project/llvm/build.cur/install/bin/llc+0x183c26c)
...
 #7 0x00000000017c375e (/data/users/yhs/work/llvm-project/llvm/build.cur/install/bin/llc+0x17c375e)
 #8 0x00000000016a75c5 llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*)
    (/data/users/yhs/work/llvm-project/llvm/build.cur/install/bin/llc+0x16a75c5)
 #9 0x00000000016ab4f8 llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*,
    unsigned int) (/data/users/yhs/work/llvm-project/llvm/build.cur/install/bin/llc+0x16ab4f8)
...
Aborted (core dumped) | llc -march=bpf -filetype=obj -o samples/bpf/test_probe_write_user_kern.o

The reason is due to llvm change https://reviews.llvm.org/D87153
where the CORE relocation global generation is moved from the beginning
of target dependent optimization (llc) to the beginning
of target independent optimization (opt).

Since samples/bpf programs did not use vmlinux.h and its clang compilation
uses native architecture, we need to adjust arch triple at opt level
to do CORE relocation global generation properly. Otherwise, the above
error will appear.

This patch fixed the issue by introduce opt and llvm-dis to compilation chain,
which will do proper CORE relocation global generation as well as O2 level
optimization. Tested with llvm10, llvm11 and trunk/llvm12.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20201006043427.1891742-1-yhs@fb.com
2020-10-06 11:45:03 -07:00
Daniel Borkmann
faef26fa44 bpf, selftests: Use bpf_tail_call_static where appropriate
For those locations where we use an immediate tail call map index use the
newly added bpf_tail_call_static() helper.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/3cfb2b799a62d22c6e7ae5897c23940bdcc24cbc.1601477936.git.daniel@iogearbox.net
2020-09-30 11:50:35 -07:00
David S. Miller
6d772f328d Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-09-23

The following pull-request contains BPF updates for your *net-next* tree.

We've added 95 non-merge commits during the last 22 day(s) which contain
a total of 124 files changed, 4211 insertions(+), 2040 deletions(-).

The main changes are:

1) Full multi function support in libbpf, from Andrii.

2) Refactoring of function argument checks, from Lorenz.

3) Make bpf_tail_call compatible with functions (subprograms), from Maciej.

4) Program metadata support, from YiFei.

5) bpf iterator optimizations, from Yonghong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-23 13:11:11 -07:00
Ilya Leoshkevich
f55f4c349a samples/bpf: Fix test_map_in_map on s390
s390 uses socketcall multiplexer instead of individual socket syscalls.
Therefore, "kprobe/" SYSCALL(sys_connect) does not trigger and
test_map_in_map fails. Fix by using "kprobe/__sys_connect" instead.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200915115519.3769807-1-iii@linux.ibm.com
2020-09-19 01:02:55 +02:00
Magnus Karlsson
74e00676d7 samples/bpf: Add quiet option to xdpsock
Add a quiet option (-Q) that disables the statistics print outs of
xdpsock. This is good to have when measuring 0% loss rate performance
as it will be quite terrible if the application uses printfs.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1599726666-8431-4-git-send-email-magnus.karlsson@gmail.com
2020-09-14 18:38:11 -07:00
Magnus Karlsson
5a2a0dd88f samples/bpf: Fix possible deadlock in xdpsock
Fix a possible deadlock in the l2fwd application in xdpsock that can
occur when there is no space in the Tx ring. There are two ways to get
the kernel to consume entries in the Tx ring: calling sendto() to make
it send packets and freeing entries from the completion ring, as the
kernel will not send a packet if there is no space for it to add a
completion entry in the completion ring. The Tx loop in l2fwd only
used to call sendto(). This patches adds cleaning the completion ring
in that loop.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1599726666-8431-3-git-send-email-magnus.karlsson@gmail.com
2020-09-14 18:38:11 -07:00
Magnus Karlsson
3131cf66d3 samples/bpf: Fix one packet sending in xdpsock
Fix the sending of a single packet (or small burst) in xdpsock when
executing in copy mode. Currently, the l2fwd application in xdpsock
only transmits the packets after a batch of them has been received,
which might be confusing if you only send one packet and expect that
it is returned pronto. Fix this by calling sendto() more often and add
a comment in the code that states that this can be optimized if
needed.

Reported-by: Tirthendu Sarkar <tirthendu.sarkar@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1599726666-8431-2-git-send-email-magnus.karlsson@gmail.com
2020-09-14 18:38:11 -07:00
Jakub Kicinski
44a8c4f33c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
We got slightly different patches removing a double word
in a comment in net/ipv4/raw.c - picked the version from net.

Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached
values instead of VNIC login response buffer (following what
commit 507ebe6444 ("ibmvnic: Fix use-after-free of VNIC login
response buffer") did).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-04 21:28:59 -07:00
Daniel T. Lee
f9bec5d756 samples, bpf: Add xsk_fwd test file to .gitignore
This commit adds xsk_fwd test file to .gitignore which is newly added
to samples/bpf.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904063434.24963-2-danieltimlee@gmail.com
2020-09-04 16:37:53 +02:00
Daniel T. Lee
698584dffd samples, bpf: Replace bpf_program__title() with bpf_program__section_name()
From commit 5210958420 ("libbpf: Deprecate notion of BPF program
"title" in favor of "section name""), the term title has been replaced
with section name in libbpf.

Since the bpf_program__title() has been deprecated, this commit
switches this function to bpf_program__section_name(). Due to
this commit, the compilation warning issue has also been resolved.

Fixes: 5210958420 ("libbpf: Deprecate notion of BPF program "title" in favor of "section name"")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904063434.24963-1-danieltimlee@gmail.com
2020-09-04 16:37:48 +02:00
Weqaar Janjua
b69e56cf76 samples/bpf: Fix to xdpsock to avoid recycling frames
The txpush program in the xdpsock sample application is supposed
to send out all packets in the umem in a round-robin fashion.
The problem is that it only cycled through the first BATCH_SIZE
worth of packets. Fixed this so that it cycles through all buffers
in the umem as intended.

Fixes: 248c7f9c0e ("samples/bpf: convert xdpsock to use libbpf for AF_XDP access")
Signed-off-by: Weqaar Janjua <weqaar.a.janjua@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20200828161717.42705-1-weqaar.a.janjua@intel.com
2020-08-31 23:00:43 +02:00
Magnus Karlsson
c8a039a47f samples/bpf: Optimize l2fwd performance in xdpsock
Optimize the throughput performance of the l2fwd sub-app in the
xdpsock sample application by removing a duplicate syscall and
increasing the size of the fill ring.

The latter needs some further explanation. We recommend that you set
the fill ring size >= HW RX ring size + AF_XDP RX ring size. Make sure
you fill up the fill ring with buffers at regular intervals, and you
will with this setting avoid allocation failures in the driver. These
are usually quite expensive since drivers have not been written to
assume that allocation failures are common. For regular sockets,
kernel allocated memory is used that only runs out in OOM situations
that should be rare.

These two performance optimizations together lead to a 6% percent
improvement for the l2fwd app on my machine.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1598619065-1944-1-git-send-email-magnus.karlsson@intel.com
2020-08-31 22:34:25 +02:00
Cristian Dumitrescu
35149b2c04 samples/bpf: Add new sample xsk_fwd.c
This sample code illustrates the packet forwarding between multiple
AF_XDP sockets in multi-threading environment. All the threads and
sockets are sharing a common buffer pool, with each socket having
its own private buffer cache. The sockets are created with the
xsk_socket__create_shared() function, which allows multiple AF_XDP
sockets to share the same UMEM object.

Example 1: Single thread handling two sockets. Packets received
from socket A (on top of interface IFA, queue QA) are forwarded
to socket B (on top of interface IFB, queue QB) and vice-versa.
The thread is affinitized to CPU core C:

./xsk_fwd -i IFA -q QA -i IFB -q QB -c C

Example 2: Two threads, each handling two sockets. Packets from
socket A are sent to socket B (by thread X), packets
from socket B are sent to socket A (by thread X); packets from
socket C are sent to socket D (by thread Y), packets from socket
D are sent to socket C (by thread Y). The two threads are bound
to CPU cores CX and CY:

./xdp_fwd -i IFA -q QA -i IFB -q QB -i IFC -q QC -i IFD -q QD -c CX -c CY

Signed-off-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-15-git-send-email-magnus.karlsson@intel.com
2020-08-31 21:17:55 +02:00
Daniel T. Lee
f0c328f8af samples: bpf: Refactor tracepoint tracing programs with libbpf
For the problem of increasing fragmentation of the bpf loader programs,
instead of using bpf_loader.o, which is used in samples/bpf, this
commit refactors the existing tracepoint tracing programs with libbbpf
bpf loader.

    - Adding a tracepoint event and attaching a bpf program to it was done
    through bpf_program_attach().
    - Instead of using the existing BPF MAP definition, MAP definition
    has been refactored with the new BTF-defined MAP format.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200823085334.9413-4-danieltimlee@gmail.com
2020-08-24 20:59:35 -07:00
Daniel T. Lee
3677d0a131 samples: bpf: Refactor kprobe tracing programs with libbpf
For the problem of increasing fragmentation of the bpf loader programs,
instead of using bpf_loader.o, which is used in samples/bpf, this
commit refactors the existing kprobe tracing programs with libbbpf
bpf loader.

    - For kprobe events pointing to system calls, the SYSCALL() macro in
    trace_common.h was used.
    - Adding a kprobe event and attaching a bpf program to it was done
    through bpf_program_attach().
    - Instead of using the existing BPF MAP definition, MAP definition
    has been refactored with the new BTF-defined MAP format.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200823085334.9413-3-danieltimlee@gmail.com
2020-08-24 20:59:35 -07:00
Daniel T. Lee
35a8b6dd33 samples: bpf: Cleanup bpf_load.o from Makefile
Since commit cc7f641d63 ("samples: bpf: Refactor BPF map performance
test with libbpf") has ommited the removal of bpf_load.o from Makefile,
this commit removes the bpf_load.o rule for targets where bpf_load.o is
not used.

Fixes: cc7f641d63 ("samples: bpf: Refactor BPF map performance test with libbpf")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200823085334.9413-2-danieltimlee@gmail.com
2020-08-24 20:59:35 -07:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Daniel T. Lee
2bf8c7e735 samples: bpf: Fix broken bpf programs due to removed symbol
>From commit f1394b7988 ("block: mark blk_account_io_completion
static") symbol blk_account_io_completion() has been marked as static,
which makes it no longer possible to attach kprobe to this event.
Currently, there are broken samples due to this reason.

As a solution to this, attach kprobe events to blk_account_io_done()
to modify them to perform the same behavior as before.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200818051641.21724-1-danieltimlee@gmail.com
2020-08-18 17:10:03 -07:00
Ilya Leoshkevich
e4d9c23207 samples/bpf, selftests/bpf: Use bpf_probe_read_kernel
A handful of samples and selftests fail to build on s390, because
after commit 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work") bpf_probe_read is not available
anymore.

Fix by using bpf_probe_read_kernel.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720114806.88823-1-iii@linux.ibm.com
2020-07-21 13:26:26 -07:00
Lorenzo Bianconi
ce4dade7f1 samples/bpf: xdp_redirect_cpu: Load a eBPF program on cpumap
Extend xdp_redirect_cpu_{usr,kern}.c adding the possibility to load
a XDP program on cpumap entries. The following options have been added:
- mprog-name: cpumap entry program name
- mprog-filename: cpumap entry program filename
- redirect-device: output interface if the cpumap program performs a
  XDP_REDIRECT to an egress interface
- redirect-map: bpf map used to perform XDP_REDIRECT to an egress
  interface
- mprog-disable: disable loading XDP program on cpumap entries

Add xdp_pass, xdp_drop, xdp_redirect stats accounting

Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/aa5a9a281b9dac425620fdabe82670ffb6bbdb92.1594734381.git.lorenzo@kernel.org
2020-07-16 17:00:32 +02:00
Lorenzo Bianconi
a4e76f1bda samples/bpf: xdp_redirect_cpu_user: Do not update bpf maps in option loop
Do not update xdp_redirect_cpu maps running while option loop but
defer it after all available options have been parsed. This is a
preliminary patch to pass the program name we want to attach to the
map entries as a user option

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/95dc46286fd2c609042948e04bb7ae1f5b425538.1594734381.git.lorenzo@kernel.org
2020-07-16 17:00:31 +02:00
Ciara Loftus
b36c3206f9 samples: bpf: Add an option for printing extra statistics in xdpsock
Introduce the --extra-stats (or simply -x) flag to the xdpsock application
which prints additional statistics alongside the regular rx and tx
counters. The new statistics printed report error conditions eg. rx ring
full, invalid descriptors, etc.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200708072835.4427-3-ciara.loftus@intel.com
2020-07-13 15:32:56 -07:00
Wenbo Zhang
eef8a42d6c bpf: Fix fds_example SIGSEGV error
The `BPF_LOG_BUF_SIZE`'s value is `UINT32_MAX >> 8`, so define an array
with it on stack caused an overflow.

Signed-off-by: Wenbo Zhang <ethercflow@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200710092035.28919-1-ethercflow@gmail.com
2020-07-10 23:25:25 +02:00
Daniel T. Lee
cc7f641d63 samples: bpf: Refactor BPF map performance test with libbpf
Previously, in order to set the numa_node attribute at the time of map
creation using "libbpf", it was necessary to call bpf_create_map_node()
directly (bpf_load approach), instead of calling bpf_object_load()
that handles everything on its own, including map creation. And because
of this problem, this sample had problems with refactoring from bpf_load
to libbbpf.

However, by commit 1bdb6c9a1c ("libbpf: Add a bunch of attribute
getters/setters for map definitions") added the numa_node attribute and
allowed it to be set in the map.

By using libbpf instead of bpf_load, the inner map definition has
been explicitly declared with BTF-defined format. Also, the element of
ARRAY_OF_MAPS was also statically specified using the BTF format. And
for this reason some logic in fixup_map() was not needed and changed
or removed.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-4-danieltimlee@gmail.com
2020-07-08 01:33:14 +02:00
Daniel T. Lee
88795b4adb samples: bpf: Refactor BPF map in map test with libbpf
From commit 646f02ffdd ("libbpf: Add BTF-defined map-in-map
support"), a way to define internal map in BTF-defined map has been
added.

Instead of using previous 'inner_map_idx' definition, the structure to
be used for the inner map can be directly defined using array directive.

    __array(values, struct inner_map)

This commit refactors map in map test program with libbpf by explicitly
defining inner map with BTF-defined format.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-3-danieltimlee@gmail.com
2020-07-08 01:33:10 +02:00
Daniel T. Lee
af9bd3e333 samples: bpf: Fix bpf programs with kprobe/sys_connect event
Currently, BPF programs with kprobe/sys_connect does not work properly.

Commit 34745aed51 ("samples/bpf: fix kprobe attachment issue on x64")
This commit modifies the bpf_load behavior of kprobe events in the x64
architecture. If the current kprobe event target starts with "sys_*",
add the prefix "__x64_" to the front of the event.

Appending "__x64_" prefix with kprobe/sys_* event was appropriate as a
solution to most of the problems caused by the commit below.

    commit d5a00528b5 ("syscalls/core, syscalls/x86: Rename struct
    pt_regs-based sys_*() to __x64_sys_*()")

However, there is a problem with the sys_connect kprobe event that does
not work properly. For __sys_connect event, parameters can be fetched
normally, but for __x64_sys_connect, parameters cannot be fetched.

    ffffffff818d3520 <__x64_sys_connect>:
    ffffffff818d3520: e8 fb df 32 00        callq   0xffffffff81c01520
    <__fentry__>
    ffffffff818d3525: 48 8b 57 60           movq    96(%rdi), %rdx
    ffffffff818d3529: 48 8b 77 68           movq    104(%rdi), %rsi
    ffffffff818d352d: 48 8b 7f 70           movq    112(%rdi), %rdi
    ffffffff818d3531: e8 1a ff ff ff        callq   0xffffffff818d3450
    <__sys_connect>
    ffffffff818d3536: 48 98                 cltq
    ffffffff818d3538: c3                    retq
    ffffffff818d3539: 0f 1f 80 00 00 00 00  nopl    (%rax)

As the assembly code for __x64_sys_connect shows, parameters should be
fetched and set into rdi, rsi, rdx registers prior to calling
__sys_connect.

Because of this problem, this commit fixes the sys_connect event by
first getting the value of the rdi register and then the value of the
rdi, rsi, and rdx register through an offset based on that value.

Fixes: 34745aed51 ("samples/bpf: fix kprobe attachment issue on x64")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-2-danieltimlee@gmail.com
2020-07-08 01:32:14 +02:00
Gaurav Singh
6903cdae9f bpf, xdp, samples: Fix null pointer dereference in *_user code
Memset on the pointer right after malloc can cause a NULL pointer
deference if it failed to allocate memory. A simple fix is to
replace malloc()/memset() pair with a simple call to calloc().

Fixes: 0fca931a6f ("samples/bpf: program demonstrating access to xdp_rxq_info")
Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
2020-06-16 14:55:35 +02:00
Daniel T. Lee
59929cd1fe samples, bpf: Refactor kprobe, tail call kern progs map definition
Because the previous two commit replaced the bpf_load implementation of
the user program with libbpf, the corresponding kernel program's MAP
definition can be replaced with new BTF-defined map syntax.

This commit only updates the samples which uses libbpf API for loading
bpf program not with bpf_load.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-6-danieltimlee@gmail.com
2020-05-19 17:13:03 +02:00
Daniel T. Lee
14846dda63 samples, bpf: Add tracex7 test file to .gitignore
This commit adds tracex7 test file (testfile.img) to .gitignore which
comes from test_override_return.sh.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-5-danieltimlee@gmail.com
2020-05-19 17:13:00 +02:00
Daniel T. Lee
bc1a85977b samples, bpf: Refactor tail call user progs with libbpf
BPF tail call uses the BPF_MAP_TYPE_PROG_ARRAY type map for calling
into other BPF programs and this PROG_ARRAY should be filled prior to
use. Currently, samples with the PROG_ARRAY type MAP fill this program
array with bpf_load. For bpf_load to fill this map, kernel BPF program
must specify the section with specific format of <prog_type>/<array_idx>
(e.g. SEC("socket/0"))

But by using libbpf instead of bpf_load, user program can specify which
programs should be added to PROG_ARRAY. The advantage of this approach
is that you can selectively add only the programs you want, rather than
adding all of them to PROG_ARRAY, and it's much more intuitive than the
traditional approach.

This commit refactors user programs with the PROG_ARRAY type MAP with
libbpf instead of using bpf_load.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-4-danieltimlee@gmail.com
2020-05-19 17:12:56 +02:00
Daniel T. Lee
63841bc083 samples, bpf: Refactor kprobe tracing user progs with libbpf
Currently, the kprobe BPF program attachment method for bpf_load is
quite old. The implementation of bpf_load "directly" controls and
manages(create, delete) the kprobe events of DEBUGFS. On the other hand,
using using the libbpf automatically manages the kprobe event.
(under bpf_link interface)

By calling bpf_program__attach(_kprobe) in libbpf, the corresponding
kprobe is created and the BPF program will be attached to this kprobe.
To remove this, by simply invoking bpf_link__destroy will clean up the
event.

This commit refactors kprobe tracing programs (tracex{1~7}_user.c) with
libbpf using bpf_link interface and bpf_program__attach.

tracex2_kern.c, which tracks system calls (sys_*), has been modified to
append prefix depending on architecture.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-3-danieltimlee@gmail.com
2020-05-19 17:12:53 +02:00
Daniel T. Lee
0efdcefb00 samples, bpf: Refactor pointer error check with libbpf
Current method of checking pointer error is not user friendly.
Especially the __must_check define makes this less intuitive.

Since, libbpf has an API libbpf_get_error() which checks pointer error,
this commit refactors existing pointer error check logic with libbpf.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-2-danieltimlee@gmail.com
2020-05-19 17:12:49 +02:00
David S. Miller
da07f52d3c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Move the bpf verifier trace check into the new switch statement in
HEAD.

Resolve the overlapping changes in hinic, where bug fixes overlap
the addition of VF support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-15 13:48:59 -07:00