This series extends map event_pipe to BPF ring buffer maps through libbpf's ring buffer manager. Records contain a size and raw bytes in plain or JSON output. CPU/index selectors remain perf-array specific. The documentation explains the shared, destructive consumer position.
The existing perf event array path is retained. Signal handlers only set a stop flag; messages and JSON closure happen in the main path. Poll and output errors return failure instead of silently ending a stream. Related request: https://github.com/libbpf/bpftool/issues/54 The series is based on bpf-next and is independent of the flags and batch-dump series sent alongside it. Validation: - Full bpftool and focused BPF selftests builds with LLVM 20, plus bpftool-map man page generation and Bash completion syntax checks. - All 12 bpftool_ringbuf subtests passed in an x86-64 KVM guest running Linux 7.3.0-rc1, against a bpftool built with only this series. - The perf event array regression also passed against unmodified bpftool. - Injecting EIO into epoll_wait returned failure with an errno diagnostic on stderr and a complete empty JSON array on stdout. Only focused tests were run; this does not claim a full BPF selftest suite run. Strict checkpatch has no errors or checks. Remaining warnings are the userspace volatile sig_atomic_t signal flag, readable multiline expected-output strings, and files covered by existing MAINTAINERS patterns. Integration check: these three independent series also applied and built together with my previously posted recursive map-dump v2 series. The combined 64 subtests passed with no skips or failures in the same guest. Tianyi Chen (2): bpftool: Read ring buffer maps with event_pipe selftests/bpf: Cover bpftool ring buffer event_pipe .../bpf/bpftool/Documentation/bpftool-map.rst | 15 +- tools/bpf/bpftool/bash-completion/bpftool | 4 +- tools/bpf/bpftool/map_perf_ring.c | 87 +++- .../bpf/prog_tests/bpftool_ringbuf.c | 381 ++++++++++++++++++ .../selftests/bpf/progs/bpftool_ringbuf.c | 47 +++ 5 files changed, 510 insertions(+), 24 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/bpftool_ringbuf.c create mode 100644 tools/testing/selftests/bpf/progs/bpftool_ringbuf.c -- 2.55.0
