Commit Graph

568 Commits

Author SHA1 Message Date
Kumar Kartikeya Dwivedi
156f886cf6 samples: bpf: Add basic infrastructure for XDP samples
This file implements some common helpers to consolidate differences in
features and functionality between the various XDP samples and give them
a consistent look, feel, and reporting capabilities.

This commit only adds support for receive statistics, which does not
rely on any tracepoint, but on the XDP program installed on the device
by each XDP redirect sample.

Some of the key features are:
 * A concise output format accompanied by helpful text explaining its
   fields.
 * An elaborate output format building upon the concise one, and folding
   out details in case of errors and staying out of view otherwise.
 * Printing driver names for devices redirecting packets.
 * Getting mac address for interface.
 * Printing summarized total statistics for the entire session.
 * Ability to dynamically switch between concise and verbose mode, using
   SIGQUIT (Ctrl + \).

In later patches, the support will be extended for each tracepoint with
its own custom output in concise and verbose mode.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-4-memxor@gmail.com
2021-08-24 14:48:40 -07:00
Kumar Kartikeya Dwivedi
50b796e645 samples: bpf: Fix a couple of warnings
cookie_uid_helper_example.c: In function ‘main’:
cookie_uid_helper_example.c:178:69: warning: ‘ -j ACCEPT’ directive
	writing 10 bytes into a region of size between 8 and 58
	[-Wformat-overflow=]
  178 |  sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
      |								       ^~~~~~~~~~
/home/kkd/src/linux/samples/bpf/cookie_uid_helper_example.c:178:9: note:
	‘sprintf’ output between 53 and 103 bytes into a destination of size 100
  178 |  sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  179 |         file);
      |         ~~~~~

Fix by using snprintf and a sufficiently sized buffer.

tracex4_user.c:35:15: warning: ‘write’ reading 12 bytes from a region of
	size 11 [-Wstringop-overread]
   35 |         key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */
      |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Use size as 11.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-2-memxor@gmail.com
2021-08-24 14:48:40 -07:00
Muhammad Falak R Wani
d1bf7c4d5d samples/bpf: Define MAX_ENTRIES instead of a magic number in offwaketime
Define MAX_ENTRIES instead of using 10000 as a magic number in various
places.

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210815065013.15411-1-falakreyaz@gmail.com
2021-08-15 00:08:40 -07:00
Muhammad Falak R Wani
d692a637b4 samples, bpf: Add an explict comment to handle nested vlan tagging.
A codeblock for handling nested vlan trips newbies into thinking it as
duplicate code. Explicitly add a comment to clarify.

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809070046.32142-1-falakreyaz@gmail.com
2021-08-10 11:17:32 +02:00
Niklas Söderlund
f4700a62c2 samples/bpf: xdpsock: Remove forward declaration of ip_fast_csum()
There is a forward declaration of ip_fast_csum() just before its
implementation, remove the unneeded forward declaration.

While at it mark the implementation as static inline.

Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Link: https://lore.kernel.org/bpf/20210806122855.26115-3-simon.horman@corigine.com
2021-08-06 16:53:27 -07:00
Niklas Söderlund
29f24c43cb samples/bpf: xdpsock: Make the sample more useful outside the tree
The xdpsock sample application is a useful base for experiment's around
AF_XDP sockets. Compiling the sample outside of the kernel tree is made
harder then it has to be as the sample includes two headers and that are
not installed by 'make install_header' nor are usually part of
distributions kernel headers.

The first header asm/barrier.h is not used and can just be dropped.

The second linux/compiler.h are only needed for the decorator __force
and are only used in ip_fast_csum(), csum_fold() and
csum_tcpudp_nofold(). These functions are copied verbatim from
include/asm-generic/checksum.h and lib/checksum.c. While it's fine to
copy and use these functions in the sample application the decorator
brings no value and can be dropped together with the include.

With this change it's trivial to compile the xdpsock sample outside the
kernel tree from xdpsock_user.c and xdpsock.h.

    $ gcc -o xdpsock xdpsock_user.c -lbpf -lpthread

Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Link: https://lore.kernel.org/bpf/20210806122855.26115-2-simon.horman@corigine.com
2021-08-06 16:53:27 -07:00
Matthew Cover
34ad6d9d8c bpf, samples: Add missing mprog-disable to xdp_redirect_cpu's optstring
Commit ce4dade7f1 ("samples/bpf: xdp_redirect_cpu: Load a eBPF program
on cpumap") added the following option, but missed adding it to optstring:

  - mprog-disable: disable loading XDP program on cpumap entries

Fix it and add the missing option character.

Fixes: ce4dade7f1 ("samples/bpf: xdp_redirect_cpu: Load a eBPF program on cpumap")
Signed-off-by: Matthew Cover <matthew.cover@stackpath.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210731005632.13228-1-matthew.cover@stackpath.com
2021-08-05 00:41:13 +02:00
Juhee Kang
05e9b4f60d samples: bpf: Add the omitted xdp samples to .gitignore
There are recently added xdp samples (xdp_redirect_map_multi and
xdpsock_ctrl_proc) which are not managed by .gitignore.

This commit adds these files to .gitignore.

Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210727041056.23455-2-claudiajkang@gmail.com
2021-07-27 11:15:09 -07:00
Juhee Kang
7d07006f05 samples: bpf: Fix tracex7 error raised on the missing argument
The current behavior of 'tracex7' doesn't consist with other bpf samples
tracex{1..6}. Other samples do not require any argument to run with, but
tracex7 should be run with btrfs device argument. (it should be executed
with test_override_return.sh)

Currently, tracex7 doesn't have any description about how to run this
program and raises an unexpected error. And this result might be
confusing since users might not have a hunch about how to run this
program.

    // Current behavior
    # ./tracex7
    sh: 1: Syntax error: word unexpected (expecting ")")
    // Fixed behavior
    # ./tracex7
    ERROR: Run with the btrfs device argument!

In order to fix this error, this commit adds logic to report a message
and exit when running this program with a missing argument.

Additionally in test_override_return.sh, there is a problem with
multiple directory(tmpmnt) creation. So in this commit adds a line with
removing the directory with every execution.

Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210727041056.23455-1-claudiajkang@gmail.com
2021-07-27 11:15:09 -07:00
David S. Miller
82a1ffe57e Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-07-15

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

We've added 45 non-merge commits during the last 15 day(s) which contain
a total of 52 files changed, 3122 insertions(+), 384 deletions(-).

The main changes are:

1) Introduce bpf timers, from Alexei.

2) Add sockmap support for unix datagram socket, from Cong.

3) Fix potential memleak and UAF in the verifier, from He.

4) Add bpf_get_func_ip helper, from Jiri.

5) Improvements to generic XDP mode, from Kumar.

6) Support for passing xdp_md to XDP programs in bpf_prog_run, from Zvi.
===================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-15 22:40:10 -07:00
Jesper Dangaard Brouer
eff94154cc samples/bpf: xdp_redirect_cpu_user: Cpumap qsize set larger default
Experience from production shows queue size of 192 is too small, as
this caused packet drops during cpumap-enqueue on RX-CPU.  This can be
diagnosed with xdp_monitor sample program.

This bpftrace program was used to diagnose the problem in more detail:

 bpftrace -e '
  tracepoint:xdp:xdp_cpumap_kthread { @deq_bulk = lhist(args->processed,0,10,1); @drop_net = lhist(args->drops,0,10,1) }
  tracepoint:xdp:xdp_cpumap_enqueue { @enq_bulk = lhist(args->processed,0,10,1); @enq_drops = lhist(args->drops,0,10,1); }'

Watch out for the @enq_drops counter. The @drop_net counter can happen
when netstack gets invalid packets, so don't despair it can be
natural, and that counter will likely disappear in newer kernels as it
was a source of confusion (look at netstat info for reason of the
netstack @drop_net counters).

The production system was configured with CPU power-saving C6 state.
Learn more in this blogpost[1].

And wakeup latency in usec for the states are:

 # grep -H . /sys/devices/system/cpu/cpu0/cpuidle/*/latency
 /sys/devices/system/cpu/cpu0/cpuidle/state0/latency:0
 /sys/devices/system/cpu/cpu0/cpuidle/state1/latency:2
 /sys/devices/system/cpu/cpu0/cpuidle/state2/latency:10
 /sys/devices/system/cpu/cpu0/cpuidle/state3/latency:133

Deepest state take 133 usec to wakeup from (133/10^6). The link speed
is 25Gbit/s ((25*10^9/8) in bytes/sec). How many bytes can arrive with
in 133 usec at this speed: (25*10^9/8)*(133/10^6) = 415625 bytes. With
MTU size packets this is 275 packets, and with minimum Ethernet (incl
intergap overhead) 84 bytes it is 4948 packets. Clearly default queue
size is too small.

Setting default cpumap queue to 2048 as worst-case (small packet) at
10Gbit/s is 1979 packets with 133 usec wakeup time, +64 packet before
kthread wakeup call (due to xdp_do_flush) worst-case 2043 packets.

Thus, if a packet burst on RX-CPU will enqueue packets to a remote
cpumap CPU that is in deep-sleep state it can overrun the cpumap queue.

The production system was also configured to avoid deep-sleep via:
 tuned-adm profile network-latency

[1] https://jeremyeder.com/2013/08/30/oh-did-you-expect-the-cpu/

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/162523477604.786243.13372630844944530891.stgit@firesoul
2021-07-07 20:11:48 -07:00
Wang Hai
2620e92ae6 bpf, samples: Fix xdpsock with '-M' parameter missing unload process
Execute the following command and exit, then execute it again, the following
error will be reported:

  $ sudo ./samples/bpf/xdpsock -i ens4f2 -M
  ^C
  $ sudo ./samples/bpf/xdpsock -i ens4f2 -M
  libbpf: elf: skipping unrecognized data section(16) .eh_frame
  libbpf: elf: skipping relo section(17) .rel.eh_frame for section(16) .eh_frame
  libbpf: Kernel error message: XDP program already attached
  ERROR: link set xdp fd failed

Commit c9d27c9e8d ("samples: bpf: Do not unload prog within xdpsock") removed
the unloading prog code because of the presence of bpf_link. This is fine if
XDP_SHARED_UMEM is disabled, but if it is enabled, unloading the prog is still
needed.

Fixes: c9d27c9e8d ("samples: bpf: Do not unload prog within xdpsock")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Cc: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210628091815.2373487-1-wanghai38@huawei.com
2021-07-05 23:34:18 +02:00
Toke Høiland-Jørgensen
5a0ae9872d bpf, samples: Add -fno-asynchronous-unwind-tables to BPF Clang invocation
The samples/bpf Makefile currently compiles BPF files in a way that will
produce an .eh_frame section, which will in turn confuse libbpf and produce
errors when loading BPF programs, like:

  libbpf: elf: skipping unrecognized data section(32) .eh_frame
  libbpf: elf: skipping relo section(33) .rel.eh_frame for section(32) .eh_frame

Fix this by instruction Clang not to produce this section, as it's useless
for BPF anyway.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210705103841.180260-1-toke@redhat.com
2021-07-05 21:56:30 +02:00
Wang Hai
7c6090ee2a samples/bpf: Fix the error return code of xdp_redirect's main()
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

If bpf_map_update_elem() failed, main() should return a negative error.

Fixes: 832622e6bd ("xdp: sample program for new bpf_redirect helper")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210616042534.315097-1-wanghai38@huawei.com
2021-06-18 11:11:52 -07:00
Wang Hai
85102ba58b samples/bpf: Fix Segmentation fault for xdp_redirect command
A Segmentation fault error is caused when the following command
is executed.

$ sudo ./samples/bpf/xdp_redirect lo
Segmentation fault

This command is missing a device <IFNAME|IFINDEX> as an argument, resulting
in out-of-bounds access from argv.

If the number of devices for the xdp_redirect parameter is not 2,
we should report an error and exit.

Fixes: 24251c2647 ("samples/bpf: add option for native and skb mode for redirect apps")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210616042324.314832-1-wanghai38@huawei.com
2021-06-18 11:10:26 -07:00
David S. Miller
a52171ae7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-06-17

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

We've added 50 non-merge commits during the last 25 day(s) which contain
a total of 148 files changed, 4779 insertions(+), 1248 deletions(-).

The main changes are:

1) BPF infrastructure to migrate TCP child sockets from a listener to another
   in the same reuseport group/map, from Kuniyuki Iwashima.

2) Add a provably sound, faster and more precise algorithm for tnum_mul() as
   noted in https://arxiv.org/abs/2105.05398, from Harishankar Vishwanathan.

3) Streamline error reporting changes in libbpf as planned out in the
   'libbpf: the road to v1.0' effort, from Andrii Nakryiko.

4) Add broadcast support to xdp_redirect_map(), from Hangbin Liu.

5) Extends bpf_map_lookup_and_delete_elem() functionality to 4 more map
   types, that is, {LRU_,PERCPU_,LRU_PERCPU_,}HASH, from Denis Salopek.

6) Support new LLVM relocations in libbpf to make them more linker friendly,
   also add a doc to describe the BPF backend relocations, from Yonghong Song.

7) Silence long standing KUBSAN complaints on register-based shifts in
   interpreter, from Daniel Borkmann and Eric Biggers.

8) Add dummy PT_REGS macros in libbpf to fail BPF program compilation when
   target arch cannot be determined, from Lorenz Bauer.

9) Extend AF_XDP to support large umems with 1M+ pages, from Magnus Karlsson.

10) Fix two minor libbpf tc BPF API issues, from Kumar Kartikeya Dwivedi.

11) Move libbpf BPF_SEQ_PRINTF/BPF_SNPRINTF macros that can be used by BPF
    programs to bpf_helpers.h header, from Florent Revest.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-17 11:54:56 -07:00
Wang Hai
dfdda1a0f4 samples/bpf: Add missing option to xdp_sample_pkts usage
xdp_sample_pkts usage() is missing the introduction of the
"-S" option, this patch adds it.

Fixes: d50ecc46d1 ("samples/bpf: Attach XDP programs in driver mode by default")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20210615135724.29528-1-wanghai38@huawei.com
2021-06-16 20:11:24 -07:00
Wang Hai
bf067f1c51 samples/bpf: Add missing option to xdp_fwd usage
xdp_fwd usage() is missing the introduction of the "-S"
and "-F" options, this patch adds it.

Fixes: d50ecc46d1 ("samples/bpf: Attach XDP programs in driver mode by default")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20210615135554.29158-1-wanghai38@huawei.com
2021-06-16 20:10:18 -07:00
Jakub Kicinski
5ada57a9a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
cdc-wdm: s/kill_urbs/poison_urbs/ to fix build

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-27 09:55:10 -07:00
Hangbin Liu
e48cfe4bbf sample/bpf: Add xdp_redirect_map_multi for redirect_map broadcast test
This is a sample for xdp redirect broadcast. In the sample we could forward
all packets between given interfaces. There is also an option -X that could
enable 2nd xdp_prog on egress interface.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210519090747.1655268-4-liuhangbin@gmail.com
2021-05-26 09:46:16 +02:00
Aditya Srivastava
4ce7d68beb samples: bpf: Ix kernel-doc syntax in file header
The opening comment mark '/**' is used for highlighting the beginning of
kernel-doc comments.
The header for samples/bpf/ibumad_kern.c follows this syntax, but
the content inside does not comply with kernel-doc.

This line was probably not meant for kernel-doc parsing, but is parsed
due to the presence of kernel-doc like comment syntax(i.e, '/**'), which
causes unexpected warnings from kernel-doc:
warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * ibumad BPF sample kernel side

Provide a simple fix by replacing this occurrence with general comment
format, i.e. '/*', to prevent kernel-doc from parsing it.

Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/bpf/20210523151408.22280-1-yashsri421@gmail.com
2021-05-24 21:06:02 -07:00
Hailong Liu
0303ce1734 samples, bpf: Suppress compiler warning
While cross compiling on ARM32 , the casting from pointer to __u64 will
cause warnings:

samples/bpf/task_fd_query_user.c: In function 'main':
samples/bpf/task_fd_query_user.c:399:23: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
399 | uprobe_file_offset = (__u64)main - (__u64)&__executable_start;
| ^
samples/bpf/task_fd_query_user.c:399:37: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
399 | uprobe_file_offset = (__u64)main - (__u64)&__executable_start;

Workaround this by using "unsigned long" to adapt to different ARCHs.

Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210511140429.89426-1-liuhailongg6@163.com
2021-05-12 12:29:43 -07:00
Magnus Karlsson
3b80d106e1 samples/bpf: Consider frame size in tx_only of xdpsock sample
Fix the tx_only micro-benchmark in xdpsock to take frame size into
consideration. It was hardcoded to the default value of frame_size
which is 4K. Changing this on the command line to 2K made half of the
packets illegal as they were outside the umem and were therefore
discarded by the kernel.

Fixes: 46738f73ea ("samples/bpf: add use of need_wakeup flag in xdpsock")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210506124349.6666-1-magnus.karlsson@gmail.com
2021-05-07 01:19:55 +02:00
Yaqi Chen
137733d08f samples/bpf: Fix broken tracex1 due to kprobe argument change
>From commit c0bbbdc32f ("__netif_receive_skb_core: pass skb by
reference"), the first argument passed into __netif_receive_skb_core
has changed to reference of a skb pointer.

This commit fixes by using bpf_probe_read_kernel.

Signed-off-by: Yaqi Chen <chendotjs@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210416154803.37157-1-chendotjs@gmail.com
2021-04-19 18:19:49 -07:00
Maciej Fijalkowski
c9d27c9e8d samples: bpf: Do not unload prog within xdpsock
With the introduction of bpf_link in xsk's libbpf part, there's no
further need for explicit unload of prog on xdpsock's termination. When
process dies, the bpf_link's refcount will be decremented and resources
will be unloaded/freed under the hood in case when there are no more
active users.

While at it, don't dump stats on error path.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-8-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Lu Wei
b0c407ec50 bpf: Remove unused headers
The header <linux/version.h> is useless in sampleip_kern.c
and trace_event_kern.c, remove it.

Signed-off-by: Lu Wei <luwei32@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210324083147.149278-1-luwei32@huawei.com
2021-03-25 22:03:46 -07:00
Masanari Iida
d94436a5d1 samples: bpf: Fix a spelling typo in do_hbm_test.sh
This patch fixes a spelling typo in do_hbm_test.sh

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210315124454.1744594-1-standby24x7@gmail.com
2021-03-15 22:17:35 -07:00
Maciej Fijalkowski
6bc6699881 samples, bpf: Add missing munmap in xdpsock
We mmap the umem region, but we never munmap it.
Add the missing call at the end of the cleanup.

Fixes: 3945b37a97 ("samples/bpf: use hugepages in xdpsock app")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20210303185636.18070-3-maciej.fijalkowski@intel.com
2021-03-04 15:53:32 +01:00
Yang Li
1132b9987a samples: bpf: Remove unneeded semicolon
Eliminate the following coccicheck warning:
./samples/bpf/cookie_uid_helper_example.c:316:3-4: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1612322248-35398-1-git-send-email-yang.lee@linux.alibaba.com
2021-02-02 21:37:59 -08:00
Tiezhu Yang
058107abaf samples/bpf: Add include dir for MIPS Loongson64 to fix build errors
There exists many build errors when make M=samples/bpf on the Loongson
platform. This issue is MIPS related, x86 compiles just fine.

Here are some errors:

  CLANG-bpf  samples/bpf/sockex2_kern.o
In file included from samples/bpf/sockex2_kern.c:2:
In file included from ./include/uapi/linux/in.h:24:
In file included from ./include/linux/socket.h:8:
In file included from ./include/linux/uio.h:8:
In file included from ./include/linux/kernel.h:11:
In file included from ./include/linux/bitops.h:32:
In file included from ./arch/mips/include/asm/bitops.h:19:
In file included from ./arch/mips/include/asm/barrier.h:11:
./arch/mips/include/asm/addrspace.h:13:10: fatal error: 'spaces.h' file not found
         ^~~~~~~~~~
1 error generated.

  CLANG-bpf  samples/bpf/sockex2_kern.o
In file included from samples/bpf/sockex2_kern.c:2:
In file included from ./include/uapi/linux/in.h:24:
In file included from ./include/linux/socket.h:8:
In file included from ./include/linux/uio.h:8:
In file included from ./include/linux/kernel.h:11:
In file included from ./include/linux/bitops.h:32:
In file included from ./arch/mips/include/asm/bitops.h:22:
In file included from ./arch/mips/include/asm/cpu-features.h:13:
In file included from ./arch/mips/include/asm/cpu-info.h:15:
In file included from ./include/linux/cache.h:6:
./arch/mips/include/asm/cache.h:12:10: fatal error: 'kmalloc.h' file not found
         ^~~~~~~~~~~
1 error generated.

  CLANG-bpf  samples/bpf/sockex2_kern.o
In file included from samples/bpf/sockex2_kern.c:2:
In file included from ./include/uapi/linux/in.h:24:
In file included from ./include/linux/socket.h:8:
In file included from ./include/linux/uio.h:8:
In file included from ./include/linux/kernel.h:11:
In file included from ./include/linux/bitops.h:32:
In file included from ./arch/mips/include/asm/bitops.h:22:
./arch/mips/include/asm/cpu-features.h:15:10: fatal error: 'cpu-feature-overrides.h' file not found
         ^~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

$ find arch/mips/include/asm -name spaces.h | sort
arch/mips/include/asm/mach-ar7/spaces.h
...
arch/mips/include/asm/mach-generic/spaces.h
...
arch/mips/include/asm/mach-loongson64/spaces.h
...
arch/mips/include/asm/mach-tx49xx/spaces.h

$ find arch/mips/include/asm -name kmalloc.h | sort
arch/mips/include/asm/mach-generic/kmalloc.h
arch/mips/include/asm/mach-ip32/kmalloc.h
arch/mips/include/asm/mach-tx49xx/kmalloc.h

$ find arch/mips/include/asm -name cpu-feature-overrides.h | sort
arch/mips/include/asm/mach-ath25/cpu-feature-overrides.h
...
arch/mips/include/asm/mach-generic/cpu-feature-overrides.h
...
arch/mips/include/asm/mach-loongson64/cpu-feature-overrides.h
...
arch/mips/include/asm/mach-tx49xx/cpu-feature-overrides.h

In the arch/mips/Makefile, there exists the following board-dependent
options:

include arch/mips/Kbuild.platforms
cflags-y += -I$(srctree)/arch/mips/include/asm/mach-generic

So we can do the similar things in samples/bpf/Makefile, just add
platform specific and generic include dir for MIPS Loongson64 to
fix the build errors.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1611669925-25315-1-git-send-email-yangtiezhu@loongson.cn
2021-02-02 23:30:14 +01:00
Tiezhu Yang
190d1c921a samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings
There exists many build warnings when make M=samples/bpf on the Loongson
platform, this issue is MIPS related, x86 compiles just fine.

Here are some warnings:

  CC  samples/bpf/ibumad_user.o
samples/bpf/ibumad_user.c: In function ‘dump_counts’:
samples/bpf/ibumad_user.c:46:24: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
    printf("0x%02x : %llu\n", key, value);
                     ~~~^          ~~~~~
                     %lu
  CC  samples/bpf/offwaketime_user.o
samples/bpf/offwaketime_user.c: In function ‘print_ksym’:
samples/bpf/offwaketime_user.c:34:17: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
   printf("%s/%llx;", sym->name, addr);
              ~~~^               ~~~~
              %lx
samples/bpf/offwaketime_user.c: In function ‘print_stack’:
samples/bpf/offwaketime_user.c:68:17: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
  printf(";%s %lld\n", key->waker, count);
              ~~~^                 ~~~~~
              %ld

MIPS needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
'int-ll64.h' in arch/mips/include/uapi/asm/types.h, then it can avoid
build warnings when printing __u64 with %llu, %llx or %lld.

The header tools/include/linux/types.h defines __SANE_USERSPACE_TYPES__,
it seems that we can include <linux/types.h> in the source files which
have build warnings, but it has no effect due to actually it includes
usr/include/linux/types.h instead of tools/include/linux/types.h, the
problem is that "usr/include" is preferred first than "tools/include"
in samples/bpf/Makefile, that sounds like a ugly hack to -Itools/include
before -Iusr/include.

So define __SANE_USERSPACE_TYPES__ for MIPS in samples/bpf/Makefile
is proper, if add "TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__" in
samples/bpf/Makefile, it appears the following error:

Auto-detecting system features:
...                        libelf: [ on  ]
...                          zlib: [ on  ]
...                           bpf: [ OFF ]

BPF API too old
make[3]: *** [Makefile:293: bpfdep] Error 1
make[2]: *** [Makefile:156: all] Error 2

With #ifndef __SANE_USERSPACE_TYPES__  in tools/include/linux/types.h,
the above error has gone and this ifndef change does not hurt other
compilations.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1611551146-14052-1-git-send-email-yangtiezhu@loongson.cn
2021-01-26 00:19:10 +01:00
Hangbin Liu
6e66fbb105 samples/bpf: Add xdp program on egress for xdp_redirect_map
This patch add a xdp program on egress to show that we can modify
the packet on egress. In this sample we will set the pkt's src
mac to egress's mac address. The xdp_prog will be attached when
-X option supplied.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20210122025007.2968381-1-liuhangbin@gmail.com
2021-01-23 00:24:37 +01:00
Tiezhu Yang
628add78b0 bpf, docs: Update build procedure for manually compiling LLVM and Clang
The current LLVM and Clang build procedure in samples/bpf/README.rst is
out of date. See below that the links are not accessible any more.

  $ git clone http://llvm.org/git/llvm.git
  Cloning into 'llvm'...
  fatal: unable to access 'http://llvm.org/git/llvm.git/': Maximum (20) redirects followed
  $ git clone --depth 1 http://llvm.org/git/clang.git
  Cloning into 'clang'...
  fatal: unable to access 'http://llvm.org/git/clang.git/': Maximum (20) redirects followed

The LLVM community has adopted new ways to build the compiler. There are
different ways to build LLVM and Clang, the Clang Getting Started page [1]
has one way. As Yonghong said, it is better to copy the build procedure
in Documentation/bpf/bpf_devel_QA.rst to keep consistent.

I verified the procedure and it is proved to be feasible, so we should
update README.rst to reflect the reality. At the same time, update the
related comment in Makefile.

Additionally, as Fangrui said, the dir llvm-project/llvm/build/install is
not used, BUILD_SHARED_LIBS=OFF is the default option [2], so also change
Documentation/bpf/bpf_devel_QA.rst together.

At last, we recommend that developers who want the fastest incremental
builds use the Ninja build system [1], you can find it in your system's
package manager, usually the package is ninja or ninja-build [3], so add
ninja to build dependencies suggested by Nathan.

  [1] https://clang.llvm.org/get_started.html
  [2] https://www.llvm.org/docs/CMake.html
  [3] https://github.com/ninja-build/ninja/wiki/Pre-built-Ninja-packages

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Fangrui Song <maskray@google.com>
Link: https://lore.kernel.org/bpf/1611279584-26047-1-git-send-email-yangtiezhu@loongson.cn
2021-01-23 00:09:03 +01:00
Björn Töpel
da9d35e2f2 samples/bpf: Add BPF_ATOMIC_OP macro for BPF samples
Brendan Jackman added extend atomic operations to the BPF instruction
set in commit 7064a7341a ("Merge branch 'Atomics for eBPF'"), which
introduces the BPF_ATOMIC_OP macro. However, that macro was missing
for the BPF samples. Fix that by adding it into bpf_insn.h.

Fixes: 91c960b005 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Link: https://lore.kernel.org/bpf/20210118091753.107572-1-bjorn.topel@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-20 14:10:35 -08:00
Brendan Jackman
91c960b005 bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.

In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.

This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.

All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
2021-01-14 18:34:29 -08:00
Magnus Karlsson
092fde0f86 samples/bpf: Fix possible hang in xdpsock with multiple threads
Fix a possible hang in xdpsock that can occur when using multiple
threads. In this case, one or more of the threads might get stuck in
the while-loop in tx_only after the user has signaled the main thread
to stop execution. In this case, no more Tx packets will be sent, so a
thread might get stuck in the aforementioned while-loop. Fix this by
introducing a test inside the while-loop to check if the benchmark has
been terminated. If so, return from the function.

Fixes: cd9e72b6f2 ("samples/bpf: xdpsock: Add option to specify batch size")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20201210163407.22066-1-magnus.karlsson@gmail.com
2020-12-10 23:13:43 +01:00
Colin Ian King
2faa7328f5 samples/bpf: Fix spelling mistake "recieving" -> "receiving"
There is a spelling mistake in an error message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20201203114452.1060017-1-colin.king@canonical.com
2020-12-03 12:18:02 -08:00
Mariusz Dudek
3627d9702d samples/bpf: Sample application for eBPF load and socket creation split
Introduce a sample program to demonstrate the control and data
plane split. For the control plane part a new program called
xdpsock_ctrl_proc is introduced. For the data plane part, some code
was added to xdpsock_user.c to act as the data plane entity.

Application xdpsock_ctrl_proc works as control entity with sudo
privileges (CAP_SYS_ADMIN and CAP_NET_ADMIN are sufficient) and the
extended xdpsock as data plane entity with CAP_NET_RAW capability
only.

Usage example:

sudo ./samples/bpf/xdpsock_ctrl_proc -i <interface>

sudo ./samples/bpf/xdpsock -i <interface> -q <queue_id>
	-n <interval> -N -l -R

Signed-off-by: Mariusz Dudek <mariuszx.dudek@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201203090546.11976-3-mariuszx.dudek@intel.com
2020-12-03 10:37:59 -08:00
Roman Gushchin
5b0764b2d3 bpf: samples: Do not touch RLIMIT_MEMLOCK
Since bpf is not using rlimit memlock for the memory accounting
and control, do not change the limit in sample applications.

Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-35-guro@fb.com
2020-12-02 18:32:47 -08:00
Björn Töpel
41bf900fe2 samples/bpf: Add option to set the busy-poll budget
Support for the SO_BUSY_POLL_BUDGET setsockopt, via the batching
option ('b').

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-11-bjorn.topel@gmail.com
2020-12-01 00:09:26 +01:00
Björn Töpel
b35fc1482c samples/bpf: Add busy-poll support to xdpsock
Add a new option to xdpsock, 'B', for busy-polling. This option will
also set the batching size, 'b' option, to the busy-poll budget.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-10-bjorn.topel@gmail.com
2020-12-01 00:09:25 +01:00
Björn Töpel
284cbc61f8 samples/bpf: Use recvfrom() in xdpsock/l2fwd
Start using recvfrom() the l2fwd scenario, instead of poll() which is
more expensive and need additional knobs for busy-polling.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-9-bjorn.topel@gmail.com
2020-12-01 00:09:25 +01:00
Björn Töpel
f2d2728220 samples/bpf: Use recvfrom() in xdpsock/rxdrop
Start using recvfrom() the rxdrop scenario.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-8-bjorn.topel@gmail.com
2020-12-01 00:09:25 +01:00
Daniel T. Lee
ceb5dea565 samples: bpf: Remove bpf_load loader completely
Numerous refactoring that rewrites BPF programs written with bpf_load
to use the libbpf loader was finally completed, resulting in BPF
programs using bpf_load within the kernel being completely no longer
present.

This commit removes bpf_load, an outdated bpf loader that is difficult
to keep up with the latest kernel BPF and causes confusion.

Also, this commit removes the unused trace_helper and bpf_load from
samples/bpf target objects from Makefile.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-8-danieltimlee@gmail.com
2020-11-26 19:33:36 -08:00
Daniel T. Lee
0afe0a998c samples: bpf: Fix lwt_len_hist reusing previous BPF map
Currently, lwt_len_hist's map lwt_len_hist_map is uses pinning, and the
map isn't cleared on test end. This leds to reuse of that map for
each test, which prevents the results of the test from being accurate.

This commit fixes the problem by removing of pinned map from bpffs.
Also, this commit add the executable permission to shell script
files.

Fixes: f74599f7c5 ("bpf: Add tests and samples for LWT-BPF")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-7-danieltimlee@gmail.com
2020-11-26 19:33:36 -08:00
Daniel T. Lee
c6497df0dd samples: bpf: Refactor test_overhead program with libbpf
This commit refactors the existing program with libbpf bpf loader.
Since the kprobe, tracepoint and raw_tracepoint bpf program can be
attached with single bpf_program__attach() interface, so the
corresponding function of libbpf is used here.

Rather than specifying the number of cpus inside the code, this commit
uses the number of available cpus with _SC_NPROCESSORS_ONLN.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201124090310.24374-6-danieltimlee@gmail.com
2020-11-26 19:33:36 -08:00
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