From 10b62d6a38f7c92e9f41983bb7d7669c9fa6e287 Mon Sep 17 00:00:00 2001 From: Hangbin Liu Date: Thu, 11 Aug 2022 11:40:20 +0800 Subject: libbpf: Add names for auxiliary maps The bpftool self-created maps can appear in final map show output due to deferred removal in kernel. These maps don't have a name, which would make users confused about where it comes from. With a libbpf_ prefix name, users could know who created these maps. It also could make some tests (like test_offload.py, which skip base maps without names as a workaround) filter them out. Kernel adds bpf prog/map name support in the same merge commit fadad670a8ab ("Merge branch 'bpf-extend-info'"). So we can also use kernel_supports(NULL, FEAT_PROG_NAME) to check if kernel supports map name. As discussed [1], Let's make bpf_map_create accept non-null name string, and silently ignore the name if kernel doesn't support. [1] https://lore.kernel.org/bpf/CAEf4BzYL1TQwo1231s83pjTdFPk9XWWhfZC5=KzkU-VO0k=0Ug@mail.gmail.com/ Signed-off-by: Hangbin Liu Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220811034020.529685-1-liuhangbin@gmail.com --- tools/lib/bpf/bpf.c | 2 +- tools/lib/bpf/libbpf.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index efcc06dafbd9..6a96e665dc5d 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -183,7 +183,7 @@ int bpf_map_create(enum bpf_map_type map_type, return libbpf_err(-EINVAL); attr.map_type = map_type; - if (map_name) + if (map_name && kernel_supports(NULL, FEAT_PROG_NAME)) libbpf_strlcpy(attr.map_name, map_name, sizeof(attr.map_name)); attr.key_size = key_size; attr.value_size = value_size; diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 917d975bd4c6..3f01f5cd8a4c 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4437,7 +4437,7 @@ static int probe_kern_global_data(void) }; int ret, map, insn_cnt = ARRAY_SIZE(insns); - map = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(int), 32, 1, NULL); + map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, NULL); if (map < 0) { ret = -errno; cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); @@ -4570,7 +4570,7 @@ static int probe_kern_array_mmap(void) LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = BPF_F_MMAPABLE); int fd; - fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(int), sizeof(int), 1, &opts); + fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts); return probe_fd(fd); } @@ -4617,7 +4617,7 @@ static int probe_prog_bind_map(void) }; int ret, map, prog, insn_cnt = ARRAY_SIZE(insns); - map = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(int), 32, 1, NULL); + map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, NULL); if (map < 0) { ret = -errno; cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); -- cgit v1.2.3