blob: e7cf6ba7b674bc94041cc28f879e7678ec2f2820 [file] [log] [blame]
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
#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 */