Hi! This series centres on NFP offload of bpf_event_output(). The first patch allows perf event arrays to be used by offloaded programs. Next patch makes the nfp driver keep track of such arrays to be able to filter FW events referring to maps. Perf event arrays are not device bound. Having driver reimplement and manage the perf array seems brittle and unnecessary.
Patch 4 moves slightly the verifier step which replaces map fds with map pointers. This is useful for nfp JIT since we can then easily replace host pointers with NFP table ids (patch 6). This allows us to lift the limitation on map helpers having to be used with the same map pointer on all paths. Second use of replacing fds with real host map pointers is that we can use the host map pointer as a key for FW events in perf event array offload. Patch 5 adds perf event output offload support for the NFP. There are some differences between bpf_event_output() offloaded and non-offloaded version. The FW messages which carry events may get dropped and reordered relatively easily. The return codes from the helper are also not guaranteed to match the host. Users are warned about some of those discrepancies with a one time warning message to kernel logs. bpftool gains an ability to dump perf ring events in a very simple format. This was very useful for testing and simple debug, maybe it will be useful to others? Last patch is a trivial comment fix. Jakub Kicinski (10): bpf: offload: allow offloaded programs to use perf event arrays nfp: bpf: record offload neutral maps in the driver bpf: export bpf_event_output() bpf: replace map pointer loads before calling into offloads nfp: bpf: perf event output helpers support nfp: bpf: rewrite map pointers with NFP TIDs tools: bpftool: fold hex keyword in command help tools: bpftool: move get_possible_cpus() to common code tools: bpftool: add simple perf event output reader bpf: fix references to free_bpf_prog_info() in comments drivers/net/ethernet/netronome/nfp/bpf/cmsg.c | 16 +- drivers/net/ethernet/netronome/nfp/bpf/fw.h | 20 +- drivers/net/ethernet/netronome/nfp/bpf/jit.c | 76 +++- drivers/net/ethernet/netronome/nfp/bpf/main.c | 28 +- drivers/net/ethernet/netronome/nfp/bpf/main.h | 24 +- .../net/ethernet/netronome/nfp/bpf/offload.c | 172 ++++++++- .../net/ethernet/netronome/nfp/bpf/verifier.c | 74 +++- drivers/net/ethernet/netronome/nfp/nfp_app.c | 2 +- include/linux/bpf.h | 5 + kernel/bpf/core.c | 1 + kernel/bpf/offload.c | 6 +- kernel/bpf/syscall.c | 2 + kernel/bpf/verifier.c | 14 +- .../bpf/bpftool/Documentation/bpftool-map.rst | 40 +- tools/bpf/bpftool/Documentation/bpftool.rst | 2 +- tools/bpf/bpftool/Makefile | 7 +- tools/bpf/bpftool/bash-completion/bpftool | 36 +- tools/bpf/bpftool/common.c | 77 +++- tools/bpf/bpftool/main.h | 7 +- tools/bpf/bpftool/map.c | 80 +--- tools/bpf/bpftool/map_perf_ring.c | 347 ++++++++++++++++++ 21 files changed, 912 insertions(+), 124 deletions(-) create mode 100644 tools/bpf/bpftool/map_perf_ring.c -- 2.17.0
