diff options
| author | Wang Nan <wangnan0@huawei.com> | 2016-11-26 07:03:27 +0000 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-11-29 12:10:19 -0300 |
| commit | 5a6acad17d2e81765dd4c2fce7346a6f045eab25 (patch) | |
| tree | c5ee94f9aec5b8ac2d1b09e7e1b8b28f927a1204 /tools/lib | |
| parent | 10931d2413478239bdceac5546cce85d7a497a4e (diff) | |
| download | linux-5a6acad17d2e81765dd4c2fce7346a6f045eab25.tar.bz2 | |
tools lib bpf: Retrive bpf_map through offset of bpf_map_def
Add a new API to libbpf, caller is able to get bpf_map through the
offset of bpf_map_def to 'maps' section.
The API will be used to help jitted perf hook code find fd of a map.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-4-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 12 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.h | 8 |
2 files changed, 20 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 866d5cdeffc7..2e974593f3e8 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1524,3 +1524,15 @@ bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) } return NULL; } + +struct bpf_map * +bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) +{ + int i; + + for (i = 0; i < obj->nr_maps; i++) { + if (obj->maps[i].offset == offset) + return &obj->maps[i]; + } + return ERR_PTR(-ENOENT); +} diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 0c0b0127e03e..a5a8b86a06fe 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -24,6 +24,7 @@ #include <stdio.h> #include <stdbool.h> #include <linux/err.h> +#include <sys/types.h> // for size_t enum libbpf_errno { __LIBBPF_ERRNO__START = 4000, @@ -200,6 +201,13 @@ struct bpf_map; struct bpf_map * bpf_object__find_map_by_name(struct bpf_object *obj, const char *name); +/* + * Get bpf_map through the offset of corresponding struct bpf_map_def + * in the bpf object file. + */ +struct bpf_map * +bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); + struct bpf_map * bpf_map__next(struct bpf_map *map, struct bpf_object *obj); #define bpf_map__for_each(pos, obj) \ |