Stanislav Fomichev says:

====================
Current setsockopt hook is limited to the size of the buffer that
user had supplied. Since we always allocate memory and copy the value
into kernel space, allocate just a little bit more in case BPF
program needs to override input data with a larger value.

The canonical example is TCP_CONGESTION socket option where
input buffer is a string and if user calls it with a short string,
BPF program has no way of extending it.

The tests are extended with TCP_CONGESTION use case.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Ignore SOL_TCP:TCP_CONGESTION in getsockopt and always override
SOL_TCP:TCP_CONGESTION with "cubic" in setsockopt hook.

Call setsockopt(SOL_TCP, TCP_CONGESTION) with short optval ("nv")
to make sure BPF program has enough buffer space to replace it
with "cubic".
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Since we always allocate memory, allocate just a little bit more
for the BPF program in case it need to override user input with
bigger value. The canonical example is TCP_CONGESTION where
input string might be too small to override (nv -> bbr or cubic).

16 bytes are chosen to match the size of TCP_CA_NAME_MAX and can
be extended in the future if needed.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Takshak said in the original submission:

With different bpf attach_flags available to attach bpf programs specially
with BPF_F_ALLOW_OVERRIDE and BPF_F_ALLOW_MULTI, the list of effective
bpf-programs available to any sub-cgroups really needs to be available for
easy debugging.

Using BPF_F_QUERY_EFFECTIVE flag, one can get the list of not only attached
bpf-programs to a cgroup but also the inherited ones from parent cgroup.

So a new option is introduced to use BPF_F_QUERY_EFFECTIVE query flag here
to list all the effective bpf-programs available for execution at a specified
cgroup.

Reused modified test program test_cgroup_attach from tools/testing/selftests/bpf:
  # ./test_cgroup_attach

With old bpftool:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/
  ID       AttachType      AttachFlags     Name
  271      egress          multi           pkt_cntr_1
  272      egress          multi           pkt_cntr_2

Attached new program pkt_cntr_4 in cg2 gives following:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2
  ID       AttachType      AttachFlags     Name
  273      egress          override        pkt_cntr_4

And with new "effective" option it shows all effective programs for cg2:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2 effective
  ID       AttachType      AttachFlags     Name
  273      egress          override        pkt_cntr_4
  271      egress          override        pkt_cntr_1
  272      egress          override        pkt_cntr_2

Compared to original submission use a local flag instead of global
option.

We need to clear query_flags on every command, in case batch mode
wants to use varying settings.

v2: (Takshak)
 - forbid duplicated flags;
 - fix cgroup path freeing.
Signed-off-by: Takshak Chahande <ctakshak@fb.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Takshak Chahande <ctakshak@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Clear buffered output once test or subtests finishes even if test was
successful. Not doing this leads to accumulation of output from previous
tests and on first failed tests lots of irrelevant output will be
dumped, greatly confusing things.

v1->v2: fix Fixes tag, add more context to patch

Fixes: 3a516a0a ("selftests/bpf: add sub-tests support for test_progs")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Petar Penkov says:

====================
This patch series introduces a BPF helper function that allows generating SYN
cookies from BPF. Currently, this helper is enabled at both the TC hook and the
XDP hook.

The first two patches in the series add/modify several TCP helper functions to
allow for SKB-less operation, as is the case at the XDP hook.

The third patch introduces the bpf_tcp_gen_syncookie helper function which
generates a SYN cookie for either XDP or TC programs. The return value of
this function contains both the MSS value, encoded in the cookie, and the
cookie itself.

The last three patches sync tools/ and add a test.

Performance evaluation:
I sent 10Mpps to a fixed port on a host with 2 10G bonded Mellanox 4 NICs from
random IPv6 source addresses. Without XDP I observed 7.2Mpps (syn-acks) being
sent out if the IPv6 packets carry 20 bytes of TCP options or 7.6Mpps if they
carry no options. If I attached a simple program that checks if a packet is
IPv6/TCP/SYN, looks up the socket, issues a cookie, and sends it back out after
swapping src/dest, recomputing the checksum, and setting the ACK flag, I
observed 10Mpps being sent back out.

Changes since v1:
1/ Added performance numbers to the cover letter
2/ Patch 2: Refactored a bit to fix compilation issues
3/ Patch 3: Changed ENOTSUPP to EOPNOTSUPP at Toke's suggestion

Changes since RFC:
1/ Cookie is returned in host order at Alexei's suggestion
2/ If cookies are not enabled via a sysctl, the helper function returns
   -ENOENT instead of -EINVAL at Lorenz's suggestion
3/ Fixed documentation to properly reflect that MSS is 16 bits at
   Lorenz's suggestion
4/ BPF helper requires TCP length to match ->doff field, rather than to simply
   be no more than 20 bytes at Eric and Alexei's suggestion
5/ Packet type is looked up from the packet version field, rather than from the
   socket. v4 packets are rejected on v6-only sockets but should work with
   dual stack listeners at Eric's suggestion
6/ Removed unnecessary `net` argument from helper function in patch 2 at
   Lorenz's suggestion
7/ Changed test to only pass MSS option so we can convince the verifier that the
   memory access is not out of bounds

Note that 7/ below illustrates the verifier might need to be extended to allow
passing a variable tcph->doff to the helper function like below:

__u32 thlen = tcph->doff * 4;
if (thlen < sizeof(*tcph))
	return;
__s64 cookie = bpf_tcp_gen_syncookie(sk, ipv4h, 20, tcph, thlen);
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Modify the existing bpf_tcp_check_syncookie test to also generate a
SYN cookie, pass the packet to the kernel, and verify that the two
cookies are the same (and both valid). Since cloned SKBs are skipped
during generic XDP, this test does not issue a SYN cookie when run in
XDP mode. We therefore only check that a valid SYN cookie was issued at
the TC hook.

Additionally, verify that the MSS for that SYN cookie is within
expected range.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Expose bpf_tcp_gen_syncookie to selftests.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Sync updated documentation for bpf_redirect_map.

Sync the bpf_tcp_gen_syncookie helper function definition with the one
in tools/uapi.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This helper function allows BPF programs to try to generate SYN
cookies, given a reference to a listener socket. The function works
from XDP and with an skb context since bpf_skc_lookup_tcp can lookup a
socket in both cases.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch allows generation of a SYN cookie before an SKB has been
allocated, as is the case at XDP.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This allows us to call this function before an SKB has been
allocated.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Toke Høiland-Jørgensen says:

====================
This series adds a new map type, devmap_hash, that works like the existing
devmap type, but using a hash-based indexing scheme. This is useful for the use
case where a devmap is indexed by ifindex (for instance for use with the routing
table lookup helper). For this use case, the regular devmap needs to be sized
after the maximum ifindex number, not the number of devices in it. A hash-based
indexing scheme makes it possible to size the map after the number of devices it
should contain instead.

This was previously part of my patch series that also turned the regular
bpf_redirect() helper into a map-based one; for this series I just pulled out
the patches that introduced the new map type.

Changelog:

v5:

- Dynamically set the number of hash buckets by rounding up max_entries to the
  nearest power of two (mirroring the regular hashmap), as suggested by Jesper.

v4:

- Remove check_memlock parameter that was left over from an earlier patch
  series.
- Reorder struct members to avoid holes.

v3:

- Rework the split into different patches
- Use spin_lock_irqsave()
- Also add documentation and bash completion definitions for bpftool

v2:

- Split commit adding the new map type so uapi and tools changes are separate.

Changes to these patches since the previous series:

- Rebase on top of the other devmap changes (makes this one simpler!)
- Don't enforce key==val, but allow arbitrary indexes.
- Rename the type to devmap_hash to reflect the fact that it's just a hashmap now.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This adds selftest and bpftool updates for the devmap_hash map type.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This adds the definition for BPF_MAP_TYPE_DEVMAP_HASH to libbpf_probes.c in
tools/lib/bpf.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This adds the devmap_hash BPF map type to the uapi headers in tools/.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

A common pattern when using xdp_redirect_map() is to create a device map
where the lookup key is simply ifindex. Because device maps are arrays,
this leaves holes in the map, and the map has to be sized to fit the
largest ifindex, regardless of how many devices actually are actually
needed in the map.

This patch adds a second type of device map where the key is looked up
using a hashmap, instead of being used as an array index. This allows maps
to be densely packed, so they can be smaller.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

The subsequent patch to add a new devmap sub-type can re-use much of the
initialisation and allocation code, so refactor it into separate functions.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

When we changed the device and CPU maps to use linked lists instead of
bitmaps, we also removed the need for the map_insert_ctx() helpers to keep
track of the bitmaps inside each map. However, it seems I forgot to remove
the function definitions stubs, so remove those here.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Andrii Nakryiko says:

====================
This patch set makes a number of changes to test_progs selftest, which is
a collection of many other tests (and sometimes sub-tests as well), to provide
better testing experience and allow to start convering many individual test
programs under selftests/bpf into a single and convenient test runner.

Patch #1 fixes issue with Makefile, which makes prog_tests/test.h compiled as
a C code. This fix allows to change how test.h is generated, providing ability
to have more control on what and how tests are run.

Patch #2 changes how test.h is auto-generated, which allows to have test
definitions, instead of just running test functions. This gives ability to do
more complicated test run policies.

Patch #3 adds `-t <test-name>` and `-n <test-num>` selectors to run only
subset of tests.

Patch #4 changes libbpf_set_print() to return previously set print callback,
allowing to temporarily replace current print callback and then set it back.
This is necessary for some tests that want more control over libbpf logging.

Patch #5 sets up and takes over libbpf logging from individual tests to
test_prog runner, adding -vv verbosity to capture debug output from libbpf.
This is useful when debugging failing tests.

Patch #6 furthers test output management and buffers it by default, emitting
log output only if test fails. This give succinct and clean default test
output. It's possible to bypass this behavior with -v flag, which will turn
off test output buffering.

Patch #7 adds support for sub-tests. It also enhances -t and -n selectors to
both support ability to specify sub-test selectors, as well as enhancing
number selector to accept sets of test, instead of just individual test
number.

Patch #8 converts bpf_verif_scale.c test to use sub-test APIs.

Patch #9 converts send_signal.c tests to use sub-test APIs.

v2->v3:
  - fix buffered output rare unitialized value bug (Alexei);
  - fix buffered output va_list reuse bug (Alexei);
  - fix buffered output truncation due to interleaving zero terminators;

v1->v2:
  - drop libbpf_swap_print, instead return previous function from
    libbpf_set_print (Stanislav);
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Convert send_signal set of tests to be exposed as three sub-tests.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Expose each BPF verifier scale test as individual sub-test to allow
independent results output and test selection.

Test run results now look like this:

  $ sudo ./test_progs -t verif/
  #3/1 loop3.o:OK
  #3/2 test_verif_scale1.o:OK
  #3/3 test_verif_scale2.o:OK
  #3/4 test_verif_scale3.o:OK
  #3/5 pyperf50.o:OK
  #3/6 pyperf100.o:OK
  #3/7 pyperf180.o:OK
  #3/8 pyperf600.o:OK
  #3/9 pyperf600_nounroll.o:OK
  #3/10 loop1.o:OK
  #3/11 loop2.o:OK
  #3/12 strobemeta.o:OK
  #3/13 strobemeta_nounroll1.o:OK
  #3/14 strobemeta_nounroll2.o:OK
  #3/15 test_sysctl_loop1.o:OK
  #3/16 test_sysctl_loop2.o:OK
  #3/17 test_xdp_loop.o:OK
  #3/18 test_seg6_loop.o:OK
  #3 bpf_verif_scale:OK
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Allow tests to have their own set of sub-tests. Also add ability to do
test/subtest selection using `-t <test-name>/<subtest-name>` and `-n
<test-nums-set>/<subtest-nums-set>`, as an extension of existing -t/-n
selector options. For the <test-num-set> format: it's a comma-separated
list of either individual test numbers (1-based), or range of test
numbers. E.g., all of the following are valid sets of test numbers:
  - 10
  - 1,2,3
  - 1-3
  - 5-10,1,3-4

'/<subtest' part is optional, but has the same format. E.g., to select
test #3 and its sub-tests #10 through #15, use: -t 3/10-15.

Similarly, to select tests by name, use `-t verif/strobe`:

  $ sudo ./test_progs -t verif/strobe
  #3/12 strobemeta.o:OK
  #3/13 strobemeta_nounroll1.o:OK
  #3/14 strobemeta_nounroll2.o:OK
  #3 bpf_verif_scale:OK
  Summary: 1/3 PASSED, 0 FAILED

Example of using subtest API is in the next patch, converting
bpf_verif_scale.c tests to use sub-tests.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch changes how test output is printed out. By default, if test
had no errors, the only output will be a single line with test number,
name, and verdict at the end, e.g.:

  #31 xdp:OK

If test had any errors, all log output captured during test execution
will be output after test completes.

It's possible to force output of log with `-v` (`--verbose`) option, in
which case output won't be buffered and will be output immediately.

To support this, individual tests are required to use helper methods for
logging: `test__printf()` and `test__vprintf()`.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Make test_progs test runner own libbpf logging. Also introduce two
levels of verbosity: -v and -vv. First one will be used in subsequent
patches to enable test log output always. Second one increases verbosity
level of libbpf logging further to include debug output as well.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

By returning previously set print callback from libbpf_set_print, it's
possible to restore it, eventually. This is useful when running many
independent test with one default print function, but overriding log
verbosity for particular subset of tests.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add ability to specify either test number or test name substring to
narrow down a set of test to run.

Usage:
sudo ./test_progs -n 1
sudo ./test_progs -t attach_probe
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Refactor test_progs to allow better control on what's being run.
Also use argp to do argument parsing, so that it's easier to keep adding
more options.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Apprently listing header as a normal dependency for a binary output
makes it go through compilation as if it was C code. This currently
works without a problem, but in subsequent commits causes problems for
differently generated test.h for test_progs. Marking those headers as
order-only dependency solves the issue.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Stanislav Fomichev says:

====================
C flow dissector supports input flags that tell it to customize parsing
by either stopping early or trying to parse as deep as possible.
BPF flow dissector always parses as deep as possible which is sub-optimal.
Pass input flags to the BPF flow dissector as well so it can make the same
decisions.

Series outline:
* remove unused FLOW_DISSECTOR_F_STOP_AT_L3 flag
* export FLOW_DISSECTOR_F_XXX flags as uapi and pass them to BPF
  flow dissector
* add documentation for the export flags
* support input flags in BPF_PROG_TEST_RUN via ctx_{in,out}
* sync uapi to tools
* support FLOW_DISSECTOR_F_PARSE_1ST_FRAG in selftest
* support FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL in kernel and selftest
* support FLOW_DISSECTOR_F_STOP_AT_ENCAP in selftest

Pros:
* makes BPF flow dissector faster by avoiding burning extra cycles
* existing BPF progs continue to work by ignoring the flags and always
  parsing as deep as possible

Cons:
* new UAPI which we need to support (OTOH, if we need to deprecate some
  flags, we can just stop setting them upon calling BPF programs)

Some numbers (with .repeat = 4000000 in test_flow_dissector):
        test_flow_dissector:PASS:ipv4-frag 35 nsec
        test_flow_dissector:PASS:ipv4-frag 35 nsec
        test_flow_dissector:PASS:ipv4-no-frag 32 nsec
        test_flow_dissector:PASS:ipv4-no-frag 32 nsec

        test_flow_dissector:PASS:ipv6-frag 39 nsec
        test_flow_dissector:PASS:ipv6-frag 39 nsec
        test_flow_dissector:PASS:ipv6-no-frag 36 nsec
        test_flow_dissector:PASS:ipv6-no-frag 36 nsec

        test_flow_dissector:PASS:ipv6-flow-label 36 nsec
        test_flow_dissector:PASS:ipv6-flow-label 36 nsec
        test_flow_dissector:PASS:ipv6-no-flow-label 33 nsec
        test_flow_dissector:PASS:ipv6-no-flow-label 33 nsec

        test_flow_dissector:PASS:ipip-encap 38 nsec
        test_flow_dissector:PASS:ipip-encap 38 nsec
        test_flow_dissector:PASS:ipip-no-encap 32 nsec
        test_flow_dissector:PASS:ipip-no-encap 32 nsec

The improvement is around 10%, but it's in a tight cache-hot
BPF_PROG_TEST_RUN loop.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Exit as soon as we found that packet is encapped when
BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP is passed.
Add appropriate selftest cases.

v2:
* Subtract sizeof(struct iphdr) from .iph_inner.tot_len (Willem de Bruijn)
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Add support for exporting ipv6 flow label via bpf_flow_keys.
Export flow label from bpf_flow.c and also return early when
BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL is passed.
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

bpf_flow.c: exit early unless BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG is
passed in flags. Also, set ip_proto earlier, this makes sure we have
correct value with fragmented packets.

Add selftest cases to test ipv4/ipv6 fragments and skip eth_get_headlen
tests that don't have BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG flag.

eth_get_headlen calls flow dissector with
BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG flag so we can't run tests that
have different set of input flags against it.

v2:
 * sefltests -> selftests (Willem de Bruijn)
 * Reword a comment about eth_get_headlen flags (Song Liu)
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Export bpf_flow_keys flags to tools/libbpf/selftests.
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This will allow us to write tests for those flags.

v2:
* Swap kfree(data) and kfree(user_ctx) (Song Liu)
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Describe what each input flag does and who uses it.
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

C flow dissector supports input flags that tell it to customize parsing
by either stopping early or trying to parse as deep as possible. Pass
those flags to the BPF flow dissector so it can make the same
decisions. In the next commits I'll add support for those flags to
our reference bpf_flow.c

v3:
* Export copy of flow dissector flags instead of moving (Alexei Starovoitov)
Acked-by: Petar Penkov <ppenkov@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Software event output is only enabled by a few prog types.
This test is to ensure that all supported types are enabled for
bpf_perf_event_output successfully.
Signed-off-by: Allan Zhang <allanzhang@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Software event output is only enabled by a few prog types right now (TC,
LWT out, XDP, sockops). Many other skb based prog types need
bpf_skb_event_output to produce software event.

Added socket_filter, cg_skb, sk_skb prog types to generate sw event.

Test bpf code is generated from code snippet:

struct TMP {
    uint64_t tmp;
} tt;
tt.tmp = 5;
bpf_perf_event_output(skb, &connection_tracking_event_map, 0,
                      &tt, sizeof(tt));
return 1;

the bpf assembly from llvm is:
       0:       b7 02 00 00 05 00 00 00         r2 = 5
       1:       7b 2a f8 ff 00 00 00 00         *(u64 *)(r10 - 8) = r2
       2:       bf a4 00 00 00 00 00 00         r4 = r10
       3:       07 04 00 00 f8 ff ff ff         r4 += -8
       4:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00    r2 = 0ll
       6:       b7 03 00 00 00 00 00 00         r3 = 0
       7:       b7 05 00 00 08 00 00 00         r5 = 8
       8:       85 00 00 00 19 00 00 00         call 25
       9:       b7 00 00 00 01 00 00 00         r0 = 1
      10:       95 00 00 00 00 00 00 00         exit
Signed-off-by: Allan Zhang <allanzhang@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Andrii Nakryiko says:

====================
There were few more tests and samples that were using custom perf buffer setup
code from trace_helpers.h. This patch set gets rid of all the usages of those
and removes helpers themselves. Libbpf provides nicer, but equally powerful
set of APIs to work with perf ring buffers, so let's have all the samples use

v1->v2:
- make logging message one long line instead of two (Song).
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>