diff options
-rw-r--r-- | tools/perf/include/bpf/bpf.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/tools/perf/include/bpf/bpf.h b/tools/perf/include/bpf/bpf.h index 04ecd425a237..bd5d7b4d7760 100644 --- a/tools/perf/include/bpf/bpf.h +++ b/tools/perf/include/bpf/bpf.h @@ -18,12 +18,20 @@ struct bpf_map { unsigned int numa_node; }; +/* + * FIXME: this should receive .max_entries as a parameter, as careful + * tuning of these limits is needed to avoid hitting limits that + * prevents other BPF constructs, such as tracepoint handlers, + * to get installed, with cryptic messages from libbpf, etc. + * For the current need, 'perf trace --filter-pids', 64 should + * be good enough, but this surely needs to be revisited. + */ #define pid_map(name, value_type) \ struct bpf_map SEC("maps") name = { \ .type = BPF_MAP_TYPE_HASH, \ .key_size = sizeof(pid_t), \ .value_size = sizeof(value_type), \ - .max_entries = 512, \ + .max_entries = 64, \ } static int (*bpf_map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags) = (void *)BPF_FUNC_map_update_elem; |