From: Feng Zhou <zhoufeng.zf@xxxxxxxxxxxxx> Trace some functions, such as enqueue_task_fair, need to access the corresponding cpu, not the current cpu, and bpf_map_lookup_elem percpu map cannot do it. So add bpf_map_lookup_percpu_elem to accomplish it for percpu_array_map, percpu_hash_map, lru_percpu_hash_map. v1->v2: Addressed comments from Alexei Starovoitov. - add a selftest for bpf_map_lookup_percpu_elem. Feng Zhou (2): bpf: add bpf_map_lookup_percpu_elem for percpu map selftests/bpf: add test case for bpf_map_lookup_percpu_elem include/linux/bpf.h | 2 + include/uapi/linux/bpf.h | 9 ++++ kernel/bpf/arraymap.c | 15 ++++++ kernel/bpf/core.c | 1 + kernel/bpf/hashtab.c | 32 +++++++++++ kernel/bpf/helpers.c | 18 +++++++ kernel/bpf/verifier.c | 17 +++++- kernel/trace/bpf_trace.c | 2 + tools/include/uapi/linux/bpf.h | 9 ++++ .../bpf/prog_tests/map_lookup_percpu_elem.c | 46 ++++++++++++++++ .../bpf/progs/test_map_lookup_percpu_elem.c | 54 +++++++++++++++++++ 11 files changed, 203 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/map_lookup_percpu_elem.c create mode 100644 tools/testing/selftests/bpf/progs/test_map_lookup_percpu_elem.c -- 2.20.1
