This set catches symbol for all BPF programs loaded/unloaded before/during/after perf-record run in a mmap-like event, PERF_RECORD_BPF_EVENT.
PERF_RECORD_BPF_EVENT includes key information of a BPF program load and unload. It is sent through perf ringbuffer, and stored in perf.data. Before this patch, perf-report will not be able to recover symbols of BPF programs once the programs are unloaded. Besides basic mmap-like information (name, addr, size), PERF_RECORD_BPF_EVENT includes BPF program id, and tag. These information can be used for detailed performance analysis like annotation. This is to follow up Alexei's early effort [2] to show bpf programs via mmap events. Thanks, Song Changes v2 -> PATCH v3: 1. Rebase on bpf-next tree, and on top of BPF sub program tag patches [1] for latest information in bpf_prog_info. 2. Complete handling and synthesizing PERF_RECORD_BPF_EVENT in perf. Changes v1 -> PATCH v2: 1. Only 3 of the 5 patches in v1, to focus on ABI first; 2. Generate PERF_RECORD_BPF_EVENT per bpf sub program instead of per prog; 3. Modify PERF_RECORD_BPF_EVENT with more details (addr, len, name), so that it can be used for basic profiling without calling sys_bpf. Changes RFC -> PATCH v1: 1. In perf-record, poll vip events in a separate thread; 2. Add tag to bpf prog name; 3. Small refactorings. [1] https://patchwork.ozlabs.org/project/netdev/list/?series=81037 [2] https://www.spinics.net/lists/netdev/msg524232.html Song Liu (4): perf, bpf: Introduce PERF_RECORD_BPF_EVENT perf: sync tools/include/uapi/linux/perf_event.h perf util: handle PERF_RECORD_BPF_EVENT perf tools: synthesize bpf event for loaded BPF programs include/linux/filter.h | 7 + include/linux/perf_event.h | 10 + include/uapi/linux/perf_event.h | 35 +++- kernel/bpf/core.c | 2 +- kernel/bpf/syscall.c | 3 + kernel/events/core.c | 123 ++++++++++++- tools/include/uapi/linux/perf_event.h | 35 +++- tools/perf/builtin-record.c | 6 + tools/perf/util/Build | 2 + tools/perf/util/bpf-event.c | 251 ++++++++++++++++++++++++++ tools/perf/util/bpf-event.h | 15 ++ tools/perf/util/event.c | 23 +++ tools/perf/util/event.h | 26 +++ tools/perf/util/evsel.c | 9 + tools/perf/util/evsel.h | 1 + tools/perf/util/machine.c | 3 + tools/perf/util/session.c | 4 + tools/perf/util/tool.h | 4 +- 18 files changed, 554 insertions(+), 5 deletions(-) create mode 100644 tools/perf/util/bpf-event.c create mode 100644 tools/perf/util/bpf-event.h -- 2.17.1
