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| author | Daniel Xu <dxu@dxuuu.xyz> | 2024-01-29 02:24:08 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-02-01 05:40:56 +0100 |
| commit | 6f3189f38a3e995232e028a4c341164c4aca1b20 (patch) | |
| tree | fd932c0339367596adb67fd652849506971fda3f /kernel/bpf/helpers.c | |
| parent | bpf: btf: Add BTF_KFUNCS_START/END macro pair (diff) | |
| download | linux-6f3189f38a3e995232e028a4c341164c4aca1b20.tar.xz linux-6f3189f38a3e995232e028a4c341164c4aca1b20.zip | |
bpf: treewide: Annotate BPF kfuncs in BTF
This commit marks kfuncs as such inside the .BTF_ids section. The upshot
of these annotations is that we'll be able to automatically generate
kfunc prototypes for downstream users. The process is as follows:
1. In source, use BTF_KFUNCS_START/END macro pair to mark kfuncs
2. During build, pahole injects into BTF a "bpf_kfunc" BTF_DECL_TAG for
each function inside BTF_KFUNCS sets
3. At runtime, vmlinux or module BTF is made available in sysfs
4. At runtime, bpftool (or similar) can look at provided BTF and
generate appropriate prototypes for functions with "bpf_kfunc" tag
To ensure future kfunc are similarly tagged, we now also return error
inside kfunc registration for untagged kfuncs. For vmlinux kfuncs,
we also WARN(), as initcall machinery does not handle errors.
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Acked-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/e55150ceecbf0a5d961e608941165c0bee7bc943.1706491398.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/helpers.c')
| -rw-r--r-- | kernel/bpf/helpers.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index bcb951a2ecf4..4db1c658254c 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -2544,7 +2544,7 @@ __bpf_kfunc void bpf_throw(u64 cookie) __bpf_kfunc_end_defs(); -BTF_SET8_START(generic_btf_ids) +BTF_KFUNCS_START(generic_btf_ids) #ifdef CONFIG_KEXEC_CORE BTF_ID_FLAGS(func, crash_kexec, KF_DESTRUCTIVE) #endif @@ -2573,7 +2573,7 @@ BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL) #endif BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_throw) -BTF_SET8_END(generic_btf_ids) +BTF_KFUNCS_END(generic_btf_ids) static const struct btf_kfunc_id_set generic_kfunc_set = { .owner = THIS_MODULE, @@ -2589,7 +2589,7 @@ BTF_ID(struct, cgroup) BTF_ID(func, bpf_cgroup_release_dtor) #endif -BTF_SET8_START(common_btf_ids) +BTF_KFUNCS_START(common_btf_ids) BTF_ID_FLAGS(func, bpf_cast_to_kern_ctx) BTF_ID_FLAGS(func, bpf_rdonly_cast) BTF_ID_FLAGS(func, bpf_rcu_read_lock) @@ -2618,7 +2618,7 @@ BTF_ID_FLAGS(func, bpf_dynptr_is_null) BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly) BTF_ID_FLAGS(func, bpf_dynptr_size) BTF_ID_FLAGS(func, bpf_dynptr_clone) -BTF_SET8_END(common_btf_ids) +BTF_KFUNCS_END(common_btf_ids) static const struct btf_kfunc_id_set common_kfunc_set = { .owner = THIS_MODULE, |