Merge branch 'annotate-kfuncs-in-btf_ids-section'

Daniel Xu says:

====================
Annotate kfuncs in .BTF_ids section

=== Description ===

This is a bpf-treewide change that annotates all kfuncs as such inside
.BTF_ids. This annotation eventually allows us to automatically generate
kfunc prototypes from bpftool.

We store this metadata inside a yet-unused flags field inside struct
btf_id_set8 (thanks Kumar!). pahole will be taught where to look.

More details about the full chain of events are available in commit 3's
description.

The accompanying pahole and bpftool changes can be viewed
here on these "frozen" branches [0][1].

[0]: https://github.com/danobi/pahole/tree/kfunc_btf-v3-mailed
[1]: https://github.com/danobi/linux/tree/kfunc_bpftool-mailed

=== Changelog ===

Changes from v3:
* Rebase to bpf-next and add missing annotation on new kfunc

Changes from v2:
* Only WARN() for vmlinux kfuncs

Changes from v1:
* Move WARN_ON() up a call level
* Also return error when kfunc set is not properly tagged
* Use BTF_KFUNCS_START/END instead of flags
* Rename BTF_SET8_KFUNC to BTF_SET8_KFUNCS
====================

Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/cover.1706491398.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

12 files changed, 34 insertions, 34 deletions

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index dfd919374017..5535f9adc658 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -617,21 +617,21 @@ CFI_NOSEAL(bpf_kfunc_call_memb_release_dtor);
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(bpf_test_modify_return_ids)
+BTF_KFUNCS_START(bpf_test_modify_return_ids)
 BTF_ID_FLAGS(func, bpf_modify_return_test)
 BTF_ID_FLAGS(func, bpf_modify_return_test2)
 BTF_ID_FLAGS(func, bpf_fentry_test1, KF_SLEEPABLE)
-BTF_SET8_END(bpf_test_modify_return_ids)
+BTF_KFUNCS_END(bpf_test_modify_return_ids)
 
 static const struct btf_kfunc_id_set bpf_test_modify_return_set = {
 	.owner = THIS_MODULE,
 	.set   = &bpf_test_modify_return_ids,
 };
 
-BTF_SET8_START(test_sk_check_kfunc_ids)
+BTF_KFUNCS_START(test_sk_check_kfunc_ids)
 BTF_ID_FLAGS(func, bpf_kfunc_call_test_release, KF_RELEASE)
 BTF_ID_FLAGS(func, bpf_kfunc_call_memb_release, KF_RELEASE)
-BTF_SET8_END(test_sk_check_kfunc_ids)
+BTF_KFUNCS_END(test_sk_check_kfunc_ids)
 
 static void *bpf_test_init(const union bpf_attr *kattr, u32 user_size,
 			   u32 size, u32 headroom, u32 tailroom)
diff --git a/net/core/filter.c b/net/core/filter.c
index 358870408a51..524adf1fa6d0 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -11982,21 +11982,21 @@ int bpf_dynptr_from_skb_rdonly(struct sk_buff *skb, u64 flags,
 	return 0;
 }
 
-BTF_SET8_START(bpf_kfunc_check_set_skb)
+BTF_KFUNCS_START(bpf_kfunc_check_set_skb)
 BTF_ID_FLAGS(func, bpf_dynptr_from_skb)
-BTF_SET8_END(bpf_kfunc_check_set_skb)
+BTF_KFUNCS_END(bpf_kfunc_check_set_skb)
 
-BTF_SET8_START(bpf_kfunc_check_set_xdp)
+BTF_KFUNCS_START(bpf_kfunc_check_set_xdp)
 BTF_ID_FLAGS(func, bpf_dynptr_from_xdp)
-BTF_SET8_END(bpf_kfunc_check_set_xdp)
+BTF_KFUNCS_END(bpf_kfunc_check_set_xdp)
 
-BTF_SET8_START(bpf_kfunc_check_set_sock_addr)
+BTF_KFUNCS_START(bpf_kfunc_check_set_sock_addr)
 BTF_ID_FLAGS(func, bpf_sock_addr_set_sun_path)
-BTF_SET8_END(bpf_kfunc_check_set_sock_addr)
+BTF_KFUNCS_END(bpf_kfunc_check_set_sock_addr)
 
-BTF_SET8_START(bpf_kfunc_check_set_tcp_reqsk)
+BTF_KFUNCS_START(bpf_kfunc_check_set_tcp_reqsk)
 BTF_ID_FLAGS(func, bpf_sk_assign_tcp_reqsk, KF_TRUSTED_ARGS)
-BTF_SET8_END(bpf_kfunc_check_set_tcp_reqsk)
+BTF_KFUNCS_END(bpf_kfunc_check_set_tcp_reqsk)
 
 static const struct btf_kfunc_id_set bpf_kfunc_set_skb = {
 	.owner = THIS_MODULE,
@@ -12075,9 +12075,9 @@ __bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(bpf_sk_iter_kfunc_ids)
+BTF_KFUNCS_START(bpf_sk_iter_kfunc_ids)
 BTF_ID_FLAGS(func, bpf_sock_destroy, KF_TRUSTED_ARGS)
-BTF_SET8_END(bpf_sk_iter_kfunc_ids)
+BTF_KFUNCS_END(bpf_sk_iter_kfunc_ids)
 
 static int tracing_iter_filter(const struct bpf_prog *prog, u32 kfunc_id)
 {
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 4869c1c2d8f3..034fb80f3fbe 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -771,11 +771,11 @@ __bpf_kfunc int bpf_xdp_metadata_rx_vlan_tag(const struct xdp_md *ctx,
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(xdp_metadata_kfunc_ids)
+BTF_KFUNCS_START(xdp_metadata_kfunc_ids)
 #define XDP_METADATA_KFUNC(_, __, name, ___) BTF_ID_FLAGS(func, name, KF_TRUSTED_ARGS)
 XDP_METADATA_KFUNC_xxx
 #undef XDP_METADATA_KFUNC
-BTF_SET8_END(xdp_metadata_kfunc_ids)
+BTF_KFUNCS_END(xdp_metadata_kfunc_ids)
 
 static const struct btf_kfunc_id_set xdp_metadata_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c
index 834edc18463a..7f518ea5f4ac 100644
--- a/net/ipv4/bpf_tcp_ca.c
+++ b/net/ipv4/bpf_tcp_ca.c
@@ -201,13 +201,13 @@ bpf_tcp_ca_get_func_proto(enum bpf_func_id func_id,
 	}
 }
 
-BTF_SET8_START(bpf_tcp_ca_check_kfunc_ids)
+BTF_KFUNCS_START(bpf_tcp_ca_check_kfunc_ids)
 BTF_ID_FLAGS(func, tcp_reno_ssthresh)
 BTF_ID_FLAGS(func, tcp_reno_cong_avoid)
 BTF_ID_FLAGS(func, tcp_reno_undo_cwnd)
 BTF_ID_FLAGS(func, tcp_slow_start)
 BTF_ID_FLAGS(func, tcp_cong_avoid_ai)
-BTF_SET8_END(bpf_tcp_ca_check_kfunc_ids)
+BTF_KFUNCS_END(bpf_tcp_ca_check_kfunc_ids)
 
 static const struct btf_kfunc_id_set bpf_tcp_ca_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/fou_bpf.c b/net/ipv4/fou_bpf.c
index 4da03bf45c9b..06e5572f296f 100644
--- a/net/ipv4/fou_bpf.c
+++ b/net/ipv4/fou_bpf.c
@@ -100,10 +100,10 @@ __bpf_kfunc int bpf_skb_get_fou_encap(struct __sk_buff *skb_ctx,
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(fou_kfunc_set)
+BTF_KFUNCS_START(fou_kfunc_set)
 BTF_ID_FLAGS(func, bpf_skb_set_fou_encap)
 BTF_ID_FLAGS(func, bpf_skb_get_fou_encap)
-BTF_SET8_END(fou_kfunc_set)
+BTF_KFUNCS_END(fou_kfunc_set)
 
 static const struct btf_kfunc_id_set fou_bpf_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
index 22358032dd48..05dc2d05bc7c 100644
--- a/net/ipv4/tcp_bbr.c
+++ b/net/ipv4/tcp_bbr.c
@@ -1155,7 +1155,7 @@ static struct tcp_congestion_ops tcp_bbr_cong_ops __read_mostly = {
 	.set_state	= bbr_set_state,
 };
 
-BTF_SET8_START(tcp_bbr_check_kfunc_ids)
+BTF_KFUNCS_START(tcp_bbr_check_kfunc_ids)
 #ifdef CONFIG_X86
 #ifdef CONFIG_DYNAMIC_FTRACE
 BTF_ID_FLAGS(func, bbr_init)
@@ -1168,7 +1168,7 @@ BTF_ID_FLAGS(func, bbr_min_tso_segs)
 BTF_ID_FLAGS(func, bbr_set_state)
 #endif
 #endif
-BTF_SET8_END(tcp_bbr_check_kfunc_ids)
+BTF_KFUNCS_END(tcp_bbr_check_kfunc_ids)
 
 static const struct btf_kfunc_id_set tcp_bbr_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
index 0fd78ecb67e7..44869ea089e3 100644
--- a/net/ipv4/tcp_cubic.c
+++ b/net/ipv4/tcp_cubic.c
@@ -485,7 +485,7 @@ static struct tcp_congestion_ops cubictcp __read_mostly = {
 	.name		= "cubic",
 };
 
-BTF_SET8_START(tcp_cubic_check_kfunc_ids)
+BTF_KFUNCS_START(tcp_cubic_check_kfunc_ids)
 #ifdef CONFIG_X86
 #ifdef CONFIG_DYNAMIC_FTRACE
 BTF_ID_FLAGS(func, cubictcp_init)
@@ -496,7 +496,7 @@ BTF_ID_FLAGS(func, cubictcp_cwnd_event)
 BTF_ID_FLAGS(func, cubictcp_acked)
 #endif
 #endif
-BTF_SET8_END(tcp_cubic_check_kfunc_ids)
+BTF_KFUNCS_END(tcp_cubic_check_kfunc_ids)
 
 static const struct btf_kfunc_id_set tcp_cubic_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/tcp_dctcp.c b/net/ipv4/tcp_dctcp.c
index bb23bb5b387a..e33fbe4933e4 100644
--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -260,7 +260,7 @@ static struct tcp_congestion_ops dctcp_reno __read_mostly = {
 	.name		= "dctcp-reno",
 };
 
-BTF_SET8_START(tcp_dctcp_check_kfunc_ids)
+BTF_KFUNCS_START(tcp_dctcp_check_kfunc_ids)
 #ifdef CONFIG_X86
 #ifdef CONFIG_DYNAMIC_FTRACE
 BTF_ID_FLAGS(func, dctcp_init)
@@ -271,7 +271,7 @@ BTF_ID_FLAGS(func, dctcp_cwnd_undo)
 BTF_ID_FLAGS(func, dctcp_state)
 #endif
 #endif
-BTF_SET8_END(tcp_dctcp_check_kfunc_ids)
+BTF_KFUNCS_END(tcp_dctcp_check_kfunc_ids)
 
 static const struct btf_kfunc_id_set tcp_dctcp_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c
index 475358ec8212..d2492d050fe6 100644
--- a/net/netfilter/nf_conntrack_bpf.c
+++ b/net/netfilter/nf_conntrack_bpf.c
@@ -467,7 +467,7 @@ __bpf_kfunc int bpf_ct_change_status(struct nf_conn *nfct, u32 status)
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(nf_ct_kfunc_set)
+BTF_KFUNCS_START(nf_ct_kfunc_set)
 BTF_ID_FLAGS(func, bpf_xdp_ct_alloc, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_xdp_ct_lookup, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_skb_ct_alloc, KF_ACQUIRE | KF_RET_NULL)
@@ -478,7 +478,7 @@ BTF_ID_FLAGS(func, bpf_ct_set_timeout, KF_TRUSTED_ARGS)
 BTF_ID_FLAGS(func, bpf_ct_change_timeout, KF_TRUSTED_ARGS)
 BTF_ID_FLAGS(func, bpf_ct_set_status, KF_TRUSTED_ARGS)
 BTF_ID_FLAGS(func, bpf_ct_change_status, KF_TRUSTED_ARGS)
-BTF_SET8_END(nf_ct_kfunc_set)
+BTF_KFUNCS_END(nf_ct_kfunc_set)
 
 static const struct btf_kfunc_id_set nf_conntrack_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/netfilter/nf_nat_bpf.c b/net/netfilter/nf_nat_bpf.c
index 6e3b2f58855f..481be15609b1 100644
--- a/net/netfilter/nf_nat_bpf.c
+++ b/net/netfilter/nf_nat_bpf.c
@@ -54,9 +54,9 @@ __bpf_kfunc int bpf_ct_set_nat_info(struct nf_conn___init *nfct,
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(nf_nat_kfunc_set)
+BTF_KFUNCS_START(nf_nat_kfunc_set)
 BTF_ID_FLAGS(func, bpf_ct_set_nat_info, KF_TRUSTED_ARGS)
-BTF_SET8_END(nf_nat_kfunc_set)
+BTF_KFUNCS_END(nf_nat_kfunc_set)
 
 static const struct btf_kfunc_id_set nf_bpf_nat_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/xfrm/xfrm_interface_bpf.c b/net/xfrm/xfrm_interface_bpf.c
index 7d5e920141e9..5ea15037ebd1 100644
--- a/net/xfrm/xfrm_interface_bpf.c
+++ b/net/xfrm/xfrm_interface_bpf.c
@@ -93,10 +93,10 @@ __bpf_kfunc int bpf_skb_set_xfrm_info(struct __sk_buff *skb_ctx, const struct bp
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(xfrm_ifc_kfunc_set)
+BTF_KFUNCS_START(xfrm_ifc_kfunc_set)
 BTF_ID_FLAGS(func, bpf_skb_get_xfrm_info)
 BTF_ID_FLAGS(func, bpf_skb_set_xfrm_info)
-BTF_SET8_END(xfrm_ifc_kfunc_set)
+BTF_KFUNCS_END(xfrm_ifc_kfunc_set)
 
 static const struct btf_kfunc_id_set xfrm_interface_kfunc_set = {
 	.owner = THIS_MODULE,
diff --git a/net/xfrm/xfrm_state_bpf.c b/net/xfrm/xfrm_state_bpf.c
index 9e20d4a377f7..2248eda741f8 100644
--- a/net/xfrm/xfrm_state_bpf.c
+++ b/net/xfrm/xfrm_state_bpf.c
@@ -117,10 +117,10 @@ __bpf_kfunc void bpf_xdp_xfrm_state_release(struct xfrm_state *x)
 
 __bpf_kfunc_end_defs();
 
-BTF_SET8_START(xfrm_state_kfunc_set)
+BTF_KFUNCS_START(xfrm_state_kfunc_set)
 BTF_ID_FLAGS(func, bpf_xdp_get_xfrm_state, KF_RET_NULL | KF_ACQUIRE)
 BTF_ID_FLAGS(func, bpf_xdp_xfrm_state_release, KF_RELEASE)
-BTF_SET8_END(xfrm_state_kfunc_set)
+BTF_KFUNCS_END(xfrm_state_kfunc_set)
 
 static const struct btf_kfunc_id_set xfrm_state_xdp_kfunc_set = {
 	.owner = THIS_MODULE,