[PATCH] kernel/bpf/syscall: fix warning defined but not used

From: Anders Roxell
Date: Tue Apr 03 2018 - 08:10:59 EST


There will be a build warning -Wunused-function if CONFIG_CGROUP_BPF
isn't defined, since the only user is inside #ifdef CONFIG_CGROUP_BPF:
kernel/bpf/syscall.c:1229:12: warning: âbpf_prog_attach_check_attach_typeâ
defined but not used [-Wunused-function]
static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Current code moves function bpf_prog_attach_check_attach_type inside
ifdef CONFIG_CGROUP_BPF.

Fixes: 5e43f899b03a ("bpf: Check attach type at prog load time")
Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
---
kernel/bpf/syscall.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7457f2676c6d..56f49557adda 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1226,18 +1226,6 @@ bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
}
}

-static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
- enum bpf_attach_type attach_type)
-{
- switch (prog->type) {
- case BPF_PROG_TYPE_CGROUP_SOCK:
- case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
- return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
- default:
- return 0;
- }
-}
-
/* last field in 'union bpf_attr' used by this command */
#define BPF_PROG_LOAD_LAST_FIELD expected_attach_type

@@ -1465,6 +1453,18 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)

#ifdef CONFIG_CGROUP_BPF

+static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
+ enum bpf_attach_type attach_type)
+{
+ switch (prog->type) {
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
+ default:
+ return 0;
+ }
+}
+
#define BPF_PROG_ATTACH_LAST_FIELD attach_flags

static int sockmap_get_from_fd(const union bpf_attr *attr,
--
2.16.2