From: Andrii Nakryiko <andriin@fb.com>
Date: Tue, 18 Aug 2020 14:33:52 -0700
Subject: libbpf: Factor out common logic of testing and closing FD
Patch-mainline: v5.10-rc1
Git-commit: bb180fb2401dfed0ba85699064e60d62af351ff9
References: bsc#1177028
Factor out common piece of logic that detects support for a feature based on
successfully created FD. Also take care of closing FD, if it was created.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200818213356.2629020-4-andriin@fb.com
Acked-by: Gary Lin <glin@suse.com>
---
tools/lib/bpf/libbpf.c | 70 +++++++++++--------------------------------------
1 file changed, 17 insertions(+), 53 deletions(-)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3430,6 +3430,13 @@ bpf_object__probe_loading(struct bpf_obj
return 0;
}
+static int probe_fd(int fd)
+{
+ if (fd >= 0)
+ close(fd);
+ return fd >= 0;
+}
+
static int probe_kern_prog_name(void)
{
struct bpf_load_program_attr attr;
@@ -3448,12 +3455,7 @@ static int probe_kern_prog_name(void)
attr.license = "GPL";
attr.name = "test";
ret = bpf_load_program_xattr(&attr, NULL, 0);
- if (ret >= 0) {
- close(ret);
- return 1;
- }
-
- return 0;
+ return probe_fd(ret);
}
static int probe_kern_global_data(void)
@@ -3494,12 +3496,7 @@ static int probe_kern_global_data(void)
ret = bpf_load_program_xattr(&prg_attr, NULL, 0);
close(map);
- if (ret >= 0) {
- close(ret);
- return 1;
- }
-
- return 0;
+ return probe_fd(ret);
}
static int probe_kern_btf_func(void)
@@ -3515,16 +3512,9 @@ static int probe_kern_btf_func(void)
/* FUNC x */ /* [3] */
BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2),
};
- int btf_fd;
- btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types),
- strs, sizeof(strs));
- if (btf_fd >= 0) {
- close(btf_fd);
- return 1;
- }
-
- return 0;
+ return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+ strs, sizeof(strs)));
}
static int probe_kern_btf_func_global(void)
@@ -3540,16 +3530,9 @@ static int probe_kern_btf_func_global(vo
/* FUNC x BTF_FUNC_GLOBAL */ /* [3] */
BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2),
};
- int btf_fd;
- btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types),
- strs, sizeof(strs));
- if (btf_fd >= 0) {
- close(btf_fd);
- return 1;
- }
-
- return 0;
+ return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+ strs, sizeof(strs)));
}
static int probe_kern_btf_datasec(void)
@@ -3566,16 +3549,9 @@ static int probe_kern_btf_datasec(void)
BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4),
BTF_VAR_SECINFO_ENC(2, 0, 4),
};
- int btf_fd;
- btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types),
- strs, sizeof(strs));
- if (btf_fd >= 0) {
- close(btf_fd);
- return 1;
- }
-
- return 0;
+ return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+ strs, sizeof(strs)));
}
static int probe_kern_array_mmap(void)
@@ -3587,14 +3563,8 @@ static int probe_kern_array_mmap(void)
.value_size = sizeof(int),
.max_entries = 1,
};
- int fd;
- fd = bpf_create_map_xattr(&attr);
- if (fd >= 0) {
- close(fd);
- return 1;
- }
- return 0;
+ return probe_fd(bpf_create_map_xattr(&attr));
}
static int probe_kern_exp_attach_type(void)
@@ -3604,7 +3574,6 @@ static int probe_kern_exp_attach_type(vo
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
};
- int fd;
memset(&attr, 0, sizeof(attr));
/* use any valid combination of program type and (optional)
@@ -3618,12 +3587,7 @@ static int probe_kern_exp_attach_type(vo
attr.insns_cnt = ARRAY_SIZE(insns);
attr.license = "GPL";
- fd = bpf_load_program_xattr(&attr, NULL, 0);
- if (fd >= 0) {
- close(fd);
- return 1;
- }
- return 0;
+ return probe_fd(bpf_load_program_xattr(&attr, NULL, 0));
}
enum kern_feature_result {