bpf: Export more bpf_burst related functions

sk_stream_memory_free() and tcp_rtx_and_write_queues_empty() are needed
to export into the BPF context for bpf_burst scheduler. But these two
functions are inline ones. So this patch added two wrappers for them,
and export the wrappers in the BPF context.

Add more bpf_burst related functions into bpf_mptcp_sched_kfunc_set to make
sure these helpers can be accessed from the BPF context.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>

Author: Geliang Tang

net/mptcp/bpf.c

@@ -213,11 +213,22 @@ bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int p
 	return data->contexts[pos];
 }
 
+__bpf_kfunc bool bpf_mptcp_subflow_queues_empty(struct sock *sk)
+{
+	return tcp_rtx_queue_empty(sk);
+}
+
 __diag_pop();
 
 BTF_KFUNCS_START(bpf_mptcp_sched_kfunc_ids)
 BTF_ID_FLAGS(func, mptcp_subflow_set_scheduled)
 BTF_ID_FLAGS(func, bpf_mptcp_subflow_ctx_by_pos)
+BTF_ID_FLAGS(func, mptcp_subflow_active)
+BTF_ID_FLAGS(func, mptcp_set_timeout)
+BTF_ID_FLAGS(func, mptcp_wnd_end)
+BTF_ID_FLAGS(func, tcp_stream_memory_free)
+BTF_ID_FLAGS(func, bpf_mptcp_subflow_queues_empty)
+BTF_ID_FLAGS(func, mptcp_pm_subflow_chk_stale)
 BTF_KFUNCS_END(bpf_mptcp_sched_kfunc_ids)
 
 static const struct btf_kfunc_id_set bpf_mptcp_sched_kfunc_set = {

net/mptcp/protocol.c

@@ -50,7 +50,7 @@ DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
 static struct net_device mptcp_napi_dev;
 
 /* Returns end sequence number of the receiver's advertised window */
-static u64 mptcp_wnd_end(const struct mptcp_sock *msk)
+u64 mptcp_wnd_end(const struct mptcp_sock *msk)
 {
 	return READ_ONCE(msk->wnd_end);
 }
@@ -489,7 +489,7 @@ static long mptcp_timeout_from_subflow(const struct mptcp_subflow_context *subfl
 	       inet_csk(ssk)->icsk_timeout - jiffies : 0;
 }
 
-static void mptcp_set_timeout(struct sock *sk)
+void mptcp_set_timeout(struct sock *sk)
 {
 	struct mptcp_subflow_context *subflow;
 	long tout = 0;

net/mptcp/protocol.h

@@ -720,6 +720,9 @@ void __mptcp_subflow_send_ack(struct sock *ssk);
 void mptcp_subflow_reset(struct sock *ssk);
 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk);
 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
+u64 mptcp_wnd_end(const struct mptcp_sock *msk);
+void mptcp_set_timeout(struct sock *sk);
+bool bpf_mptcp_subflow_queues_empty(struct sock *sk);
 struct mptcp_subflow_context *
 bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos);
 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk);