This patch set implements initial version (as discussed at LSF/MM2019 conference) of a new way to specify BPF maps, relying on BTF type information, which allows for easy extensibility, preserving forward and backward compatibility. See details and examples in description for patch #6. [0] contains an outline of follow up extensions to be added after this basic set of features lands. They are useful by itself, but also allows to bring libbpf to feature-parity with iproute2 BPF loader. That should open a path forward for BPF loaders unification. Patch #1 centralizes commonly used min/max macro in libbpf_internal.h. Patch #2 extracts .BTF and .BTF.ext loading loging from elf_collect(). Patch #3 simplifies elf_collect() error-handling logic. Patch #4 refactors map initialization logic into user-provided maps and global data maps, in preparation to adding another way (BTF-defined maps). Patch #5 adds support for map definitions in multiple ELF sections and deprecates bpf_object__find_map_by_offset() API which doesn't appear to be used anymore and makes assumption that all map definitions reside in single ELF section. Patch #6 splits BTF intialization from sanitization/loading into kernel to preserve original BTF at the time of map initialization. Patch #7 adds support for BTF-defined maps. Patch #8 adds new test for BTF-defined map definition. Patches #9-11 convert test BPF map definitions to use BTF way. [0] https://lore.kernel.org/bpf/CAEf4BzbfdG2ub7gCi0OYqBrUoChVHWsmOntWAkJt47=FE+km+A@xxxxxxxxxxxxxx/ v1->v2: - more BTF-sanity checks in parsing map definitions (Song); - removed confusing usage of "attribute", switched to "field; - split off elf_collect() refactor from btf loading refactor (Song); - split selftests conversion into 3 patches (Stanislav): 1. test already relying on BTF; 2. tests w/ custom types as key/value (so benefiting from BTF); 3. all the rest tests (integers as key/value, special maps w/o BTF support). - smaller code improvements (Song); rfc->v1: - error out on unknown field by default (Stanislav, Jakub, Lorenz); Andrii Nakryiko (11): libbpf: add common min/max macro to libbpf_internal.h libbpf: extract BTF loading logic libbpf: streamline ELF parsing error-handling libbpf: refactor map initialization libbpf: identify maps by section index in addition to offset libbpf: split initialization and loading of BTF libbpf: allow specifying map definitions using BTF selftests/bpf: add test for BTF-defined maps selftests/bpf: switch BPF_ANNOTATE_KV_PAIR tests to BTF-defined maps selftests/bpf: convert tests w/ custom values to BTF-defined maps selftests/bpf: convert remaining selftests to BTF-defined maps tools/lib/bpf/bpf.c | 7 +- tools/lib/bpf/bpf_prog_linfo.c | 5 +- tools/lib/bpf/btf.c | 3 - tools/lib/bpf/btf.h | 1 + tools/lib/bpf/btf_dump.c | 3 - tools/lib/bpf/libbpf.c | 781 +++++++++++++----- tools/lib/bpf/libbpf_internal.h | 7 + tools/testing/selftests/bpf/progs/bpf_flow.c | 18 +- .../selftests/bpf/progs/get_cgroup_id_kern.c | 18 +- .../testing/selftests/bpf/progs/netcnt_prog.c | 22 +- .../selftests/bpf/progs/sample_map_ret0.c | 18 +- .../selftests/bpf/progs/socket_cookie_prog.c | 11 +- .../bpf/progs/sockmap_verdict_prog.c | 36 +- .../selftests/bpf/progs/test_btf_newkv.c | 73 ++ .../bpf/progs/test_get_stack_rawtp.c | 27 +- .../selftests/bpf/progs/test_global_data.c | 27 +- tools/testing/selftests/bpf/progs/test_l4lb.c | 45 +- .../selftests/bpf/progs/test_l4lb_noinline.c | 45 +- .../selftests/bpf/progs/test_map_in_map.c | 20 +- .../selftests/bpf/progs/test_map_lock.c | 22 +- .../testing/selftests/bpf/progs/test_obj_id.c | 9 +- .../bpf/progs/test_select_reuseport_kern.c | 45 +- .../bpf/progs/test_send_signal_kern.c | 22 +- .../bpf/progs/test_skb_cgroup_id_kern.c | 9 +- .../bpf/progs/test_sock_fields_kern.c | 60 +- .../selftests/bpf/progs/test_spin_lock.c | 33 +- .../bpf/progs/test_stacktrace_build_id.c | 44 +- .../selftests/bpf/progs/test_stacktrace_map.c | 40 +- .../testing/selftests/bpf/progs/test_tc_edt.c | 9 +- .../bpf/progs/test_tcp_check_syncookie_kern.c | 9 +- .../selftests/bpf/progs/test_tcp_estats.c | 9 +- .../selftests/bpf/progs/test_tcpbpf_kern.c | 18 +- .../selftests/bpf/progs/test_tcpnotify_kern.c | 18 +- tools/testing/selftests/bpf/progs/test_xdp.c | 18 +- .../selftests/bpf/progs/test_xdp_noinline.c | 60 +- tools/testing/selftests/bpf/test_btf.c | 10 +- .../selftests/bpf/test_queue_stack_map.h | 20 +- .../testing/selftests/bpf/test_sockmap_kern.h | 72 +- 38 files changed, 1199 insertions(+), 495 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_btf_newkv.c -- 2.17.1
