@@ -2113,6 +2113,9 @@ bool bpf_prog_has_kfunc_call(const struct bpf_prog *prog);
const struct btf_func_model *
bpf_jit_find_kfunc_model(const struct bpf_prog *prog,
const struct bpf_insn *insn);
+void bpf_rcu_read_lock(void);
+void bpf_rcu_read_unlock(void);
+
struct bpf_core_ctx {
struct bpf_verifier_log *log;
const struct btf *btf;
@@ -199,6 +199,7 @@ DEFINE_IDR(btf_idr);
DEFINE_SPINLOCK(btf_idr_lock);
enum btf_kfunc_hook {
+ BTF_KFUNC_HOOK_GENERIC,
BTF_KFUNC_HOOK_XDP,
BTF_KFUNC_HOOK_TC,
BTF_KFUNC_HOOK_STRUCT_OPS,
@@ -7499,6 +7500,8 @@ static u32 *__btf_kfunc_id_set_contains(const struct btf *btf,
static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type)
{
switch (prog_type) {
+ case BPF_PROG_TYPE_UNSPEC:
+ return BTF_KFUNC_HOOK_GENERIC;
case BPF_PROG_TYPE_XDP:
return BTF_KFUNC_HOOK_XDP;
case BPF_PROG_TYPE_SCHED_CLS:
@@ -7527,6 +7530,11 @@ u32 *btf_kfunc_id_set_contains(const struct btf *btf,
u32 kfunc_btf_id)
{
enum btf_kfunc_hook hook;
+ u32 *kfunc_flags;
+
+ kfunc_flags = __btf_kfunc_id_set_contains(btf, BTF_KFUNC_HOOK_GENERIC, kfunc_btf_id);
+ if (kfunc_flags)
+ return kfunc_flags;
hook = bpf_prog_type_to_kfunc_hook(prog_type);
return __btf_kfunc_id_set_contains(btf, hook, kfunc_btf_id);
@@ -1717,9 +1717,32 @@ static const struct btf_kfunc_id_set tracing_kfunc_set = {
.set = &tracing_btf_ids,
};
+void bpf_rcu_read_lock(void)
+{
+ rcu_read_lock();
+}
+
+void bpf_rcu_read_unlock(void)
+{
+ rcu_read_unlock();
+}
+
+BTF_SET8_START(generic_btf_ids)
+BTF_ID_FLAGS(func, bpf_rcu_read_lock)
+BTF_ID_FLAGS(func, bpf_rcu_read_unlock)
+BTF_SET8_END(generic_btf_ids)
+
+static const struct btf_kfunc_id_set generic_kfunc_set = {
+ .owner = THIS_MODULE,
+ .set = &generic_btf_ids,
+};
+
static int __init kfunc_init(void)
{
- return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &tracing_kfunc_set);
+ int ret;
+
+ ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &tracing_kfunc_set);
+ return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &generic_kfunc_set);
}
late_initcall(kfunc_init);
Add two kfunc's bpf_rcu_read_lock() and bpf_rcu_read_unlock(). These two kfunc's can be used for all program types. A new kfunc hook type BTF_KFUNC_HOOK_GENERIC is added which corresponds to prog type BPF_PROG_TYPE_UNSPEC, indicating the kfunc intends to be used for all prog types. Signed-off-by: Yonghong Song <yhs@fb.com> --- include/linux/bpf.h | 3 +++ kernel/bpf/btf.c | 8 ++++++++ kernel/bpf/helpers.c | 25 ++++++++++++++++++++++++- 3 files changed, 35 insertions(+), 1 deletion(-)