[PATCH bpf-next v2 3/5] bpf: Extend bpf_base_func_proto helpers with bpf_get_current_task_btf()

From: Daniel Xu
Date: Mon Aug 23 2021 - 22:44:31 EST


bpf_get_current_task() is already supported so it's natural to also
include the _btf() variant for btf-powered helpers.

This is required for non-tracing progs to use bpf_task_pt_regs() in the
next commit.

Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
---
kernel/bpf/helpers.c | 3 +++
kernel/trace/bpf_trace.c | 2 +-
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 4e8540716187..609674f409ed 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -1322,6 +1322,7 @@ void bpf_timer_cancel_and_free(void *val)
}

const struct bpf_func_proto bpf_get_current_task_proto __weak;
+const struct bpf_func_proto bpf_get_current_task_btf_proto __weak;
const struct bpf_func_proto bpf_probe_read_user_proto __weak;
const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
@@ -1407,6 +1408,8 @@ bpf_base_func_proto(enum bpf_func_id func_id)
return bpf_get_trace_printk_proto();
case BPF_FUNC_get_current_task:
return &bpf_get_current_task_proto;
+ case BPF_FUNC_get_current_task_btf:
+ return &bpf_get_current_task_btf_proto;
case BPF_FUNC_probe_read_user:
return &bpf_probe_read_user_proto;
case BPF_FUNC_probe_read_kernel:
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 50d055fc2327..4e54f3dc209f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -716,7 +716,7 @@ BPF_CALL_0(bpf_get_current_task_btf)

BTF_ID_LIST_GLOBAL_SINGLE(btf_task_struct_ids, struct, task_struct)

-static const struct bpf_func_proto bpf_get_current_task_btf_proto = {
+const struct bpf_func_proto bpf_get_current_task_btf_proto = {
.func = bpf_get_current_task_btf,
.gpl_only = true,
.ret_type = RET_PTR_TO_BTF_ID,
--
2.33.0