fix(modern): prevent CO-RE relocations when CONFIG_QUOTACTL is not defined

[Andreagit97]

What type of PR is this?

/kind bug

Any specific area of the project related to this PR?

/area driver-modern-bpf

Does this PR require a change in the driver versions?

No

What this PR does / why we need it:

When CONFIG_QUOTACTL is not defined we need to avoid relocations on structs that are not defined like struct if_dqblk.
Running bpftool btf dump file /sys/kernel/btf/vmlinux format c | grep if_dqblk against a kernel compiled without CONFIG_QUOTACTL will show the absence of struct if_dqblk and so we cannot relocate against it.

Which issue(s) this PR fixes:
Fixes #2033

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[FedeDP]

/approve

Thank you Andre! Great fix!

[poiana]

LGTM label has been added.

Git tree hash: d3e3213dee9299f2d2fedb341806fe9b58e08f24

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Andreagit97, FedeDP

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files:

• driver/OWNERS [Andreagit97,FedeDP]

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[github-actions]

Perf diff from master - unit tests

     6.26%     -1.42%  [.] sinsp_evt::get_type
     5.77%     -1.23%  [.] next
     9.65%     +0.72%  [.] sinsp_parser::reset
     1.28%     +0.70%  [.] std::_Hashtable<long, std::pair<long const, std::shared_ptr<sinsp_threadinfo> >, std::allocator<std::pair<long const, std::shared_ptr<sinsp_threadinfo> > >, std::__detail::_Select1st, std::equal_to<long>, std::hash<long>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true> >::_M_find_before_node
     2.21%     -0.63%  [.] std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release
     4.22%     +0.57%  [.] sinsp_evt::load_params
     1.16%     -0.56%  [.] scap_next
     1.15%     +0.54%  [.] std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_construct<char const*>
     0.83%     +0.44%  [.] std::vector<sinsp_evt_param, std::allocator<sinsp_evt_param> >::emplace_back<sinsp_evt*, unsigned int&, char const*, unsigned long&>
     0.79%     +0.44%  [.] sinsp_filter_check::parse_field_name

Heap diff from master - unit tests

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Heap diff from master - scap file

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Benchmarks diff from master

Comparing gbench_data.json to /root/actions-runner/_work/libs/libs/build/gbench_data.json
Benchmark                                                         Time             CPU      Time Old      Time New       CPU Old       CPU New
----------------------------------------------------------------------------------------------------------------------------------------------
BM_sinsp_split_mean                                            +0.0278         +0.0279           145           149           145           149
BM_sinsp_split_median                                          +0.0293         +0.0294           145           149           145           149
BM_sinsp_split_stddev                                          -0.1279         -0.1294             1             1             1             1
BM_sinsp_split_cv                                              -0.1515         -0.1530             0             0             0             0
BM_sinsp_concatenate_paths_relative_path_mean                  +0.0963         +0.0964            42            46            42            46
BM_sinsp_concatenate_paths_relative_path_median                +0.0971         +0.0972            42            46            42            46
BM_sinsp_concatenate_paths_relative_path_stddev                -0.4948         -0.4948             0             0             0             0
BM_sinsp_concatenate_paths_relative_path_cv                    -0.5392         -0.5393             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_mean                     -0.0239         -0.0238            17            17            17            17
BM_sinsp_concatenate_paths_empty_path_median                   -0.0311         -0.0310            17            17            17            17
BM_sinsp_concatenate_paths_empty_path_stddev                   +0.7307         +0.7295             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_cv                       +0.7731         +0.7716             0             0             0             0
BM_sinsp_concatenate_paths_absolute_path_mean                  +0.1563         +0.1564            43            49            43            49
BM_sinsp_concatenate_paths_absolute_path_median                +0.1616         +0.1617            43            50            43            50
BM_sinsp_concatenate_paths_absolute_path_stddev                +2.7107         +2.7137             0             1             0             1
BM_sinsp_concatenate_paths_absolute_path_cv                    +2.2091         +2.2114             0             0             0             0
BM_sinsp_split_container_image_mean                            -0.0186         -0.0185           349           342           349           342
BM_sinsp_split_container_image_median                          -0.0217         -0.0216           350           342           349           342
BM_sinsp_split_container_image_stddev                          -0.4378         -0.4381             3             2             3             2
BM_sinsp_split_container_image_cv                              -0.4271         -0.4275             0             0             0             0

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.30%. Comparing base (5ed00b2) to head (d1d6211).
Report is 3 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2042   +/-   ##
=======================================
  Coverage   74.30%   74.30%           
=======================================
  Files         253      253           
  Lines       30966    30966           
  Branches     5414     5410    -4     
=======================================
  Hits        23010    23010           
+ Misses       7951     7949    -2     
- Partials        5        7    +2     

Flag	Coverage Δ
libsinsp	74.30% <ø> (ø)

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[github-actions]

X64 kernel testing matrix

KERNEL	CMAKE-CONFIGURE	KMOD BUILD	KMOD SCAP-OPEN	BPF-PROBE BUILD	BPF-PROBE SCAP-OPEN	MODERN-BPF SCAP-OPEN
amazonlinux2-4.19	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2-5.10	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2-5.15	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2-5.4	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2022-5.15	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2023-6.1	🟢	🟢	🟢	🟢	🟢	🟢
archlinux-6.0	🟢	🟢	🟢	🟢	🟢	🟢
archlinux-6.7	🟢	🟢	🟢	🟢	🟢	🟢
centos-3.10	🟢	🟢	🟢	🟡	🟡	🟡
centos-4.18	🟢	🟢	🟢	🟢	🟢	🟢
centos-5.14	🟢	🟢	🟢	🟢	🟢	🟢
fedora-5.17	🟢	🟢	🟢	🟢	🟢	🟢
fedora-5.8	🟢	🟢	🟢	🟢	🟢	🟢
fedora-6.2	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-3.10	🟢	🟢	🟢	🟡	🟡	🟡
oraclelinux-4.14	🟢	🟢	🟢	🟢	🟢	🟡
oraclelinux-5.15	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-5.4	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-4.15	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-5.8	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-6.5	🟢	🟢	🟢	🟢	🟢	🟢

ARM64 kernel testing matrix

KERNEL	CMAKE-CONFIGURE	KMOD BUILD	KMOD SCAP-OPEN	BPF-PROBE BUILD	BPF-PROBE SCAP-OPEN	MODERN-BPF SCAP-OPEN
amazonlinux2-5.4	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2022-5.15	🟢	🟢	🟢	🟢	🟢	🟢
fedora-6.2	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-4.14	🟢	🟢	🟢	🟡	🟡	🟡
oraclelinux-5.15	🟢	🟢	🟢	🟢	🟢	🟢
ubuntu-6.5	🟢	🟢	🟢	🟢	🟢	🟢

[hhoffstaette]

Verified that it fixes the problem - thanks!