| /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ |
| #ifndef __LIBPERF_BPF_PERF_H |
| #define __LIBPERF_BPF_PERF_H |
| |
| #include <linux/types.h> /* for __u32 */ |
| |
| /* |
| * bpf_perf uses a hashmap, the attr_map, to track all the leader programs. |
| * The hashmap is pinned in bpffs. flock() on this file is used to ensure |
| * no concurrent access to the attr_map. The key of attr_map is struct |
| * perf_event_attr, and the value is struct perf_event_attr_map_entry. |
| * |
| * struct perf_event_attr_map_entry contains two __u32 IDs, bpf_link of the |
| * leader prog, and the diff_map. Each perf-stat session holds a reference |
| * to the bpf_link to make sure the leader prog is attached to sched_switch |
| * tracepoint. |
| * |
| * Since the hashmap only contains IDs of the bpf_link and diff_map, it |
| * does not hold any references to the leader program. Once all perf-stat |
| * sessions of these events exit, the leader prog, its maps, and the |
| * perf_events will be freed. |
| */ |
| struct perf_event_attr_map_entry { |
| __u32 link_id; |
| __u32 diff_map_id; |
| }; |
| |
| /* default attr_map name */ |
| #define BPF_PERF_DEFAULT_ATTR_MAP_PATH "perf_attr_map" |
| |
| #endif /* __LIBPERF_BPF_PERF_H */ |
