From: Song Liu <song@kernel.org> By following the same protocol, other tools can share hardware PMCs with perf. Move perf_event_attr_map_entry and BPF_PERF_DEFAULT_ATTR_MAP_PATH to bpf_perf.h for other tools to use. Signed-off-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: kernel-team@fb.com Link: https://lore.kernel.org/r/20210425214333.1090950-2-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> --- tools/lib/perf/include/perf/bpf_perf.h | 31 ++++++++++++++++++++++++++ tools/perf/util/bpf_counter.c | 27 +++------------------- 2 files changed, 34 insertions(+), 24 deletions(-) create mode 100644 tools/lib/perf/include/perf/bpf_perf.h diff --git a/tools/lib/perf/include/perf/bpf_perf.h b/tools/lib/perf/include/perf/bpf_perf.h new file mode 100644 index 000000000000..e7cf6ba7b674 --- /dev/null +++ b/tools/lib/perf/include/perf/bpf_perf.h @@ -0,0 +1,31 @@ +/* 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 */ diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c index 81d1df3c4ec0..be484ddbbd5b 100644 --- a/tools/perf/util/bpf_counter.c +++ b/tools/perf/util/bpf_counter.c @@ -14,6 +14,7 @@ #include <bpf/btf.h> #include <bpf/libbpf.h> #include <api/fs/fs.h> +#include <perf/bpf_perf.h> #include "bpf_counter.h" #include "counts.h" @@ -29,28 +30,6 @@ #include "bpf_skel/bperf_leader.skel.h" #include "bpf_skel/bperf_follower.skel.h" -/* - * bperf 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; -}; - -#define DEFAULT_ATTR_MAP_PATH "fs/bpf/perf_attr_map" #define ATTR_MAP_SIZE 16 static inline void *u64_to_ptr(__u64 ptr) @@ -341,8 +320,8 @@ static int bperf_lock_attr_map(struct target *target) if (target->attr_map) { scnprintf(path, PATH_MAX, "%s", target->attr_map); } else { - scnprintf(path, PATH_MAX, "%s/%s", sysfs__mountpoint(), - DEFAULT_ATTR_MAP_PATH); + scnprintf(path, PATH_MAX, "%s/fs/bpf/%s", sysfs__mountpoint(), + BPF_PERF_DEFAULT_ATTR_MAP_PATH); } if (access(path, F_OK)) { -- 2.34.1