This patch added a new struct member sched in struct mptcp_sock.
And two helpers mptcp_init_sched() and mptcp_release_sched() to
init and release it.

Init it with the sysctl scheduler in mptcp_init_sock(), copy the
scheduler from the parent in mptcp_sk_clone(), and release it in
__mptcp_destroy_sock().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 net/mptcp/protocol.c |  4 ++++
 net/mptcp/protocol.h |  4 ++++
 net/mptcp/sched.c    | 20 ++++++++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 11e19ac9d5af..c892e3b6b65c 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2609,6 +2609,8 @@ static int mptcp_init_sock(struct sock *sk)
 	 * propagate the correct value
 	 */
 	mptcp_ca_reset(sk);
+	mptcp_init_sched(mptcp_sk(sk),
+			 mptcp_sched_find(mptcp_get_scheduler(net)));
 
 	sk_sockets_allocated_inc(sk);
 	sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1];
@@ -2760,6 +2762,7 @@ static void __mptcp_destroy_sock(struct sock *sk)
 	sk_stop_timer(sk, &msk->sk.icsk_retransmit_timer);
 	sk_stop_timer(sk, &sk->sk_timer);
 	msk->pm.status = 0;
+	mptcp_release_sched(msk);
 
 	/* clears msk->subflow, allowing the following loop to close
 	 * even the initial subflow
@@ -2933,6 +2936,7 @@ struct sock *mptcp_sk_clone(const struct sock *sk,
 	msk->snd_una = msk->write_seq;
 	msk->wnd_end = msk->snd_nxt + req->rsk_rcv_wnd;
 	msk->setsockopt_seq = mptcp_sk(sk)->setsockopt_seq;
+	mptcp_init_sched(msk, mptcp_sk(sk)->sched);
 
 	if (mp_opt->suboptions & OPTIONS_MPTCP_MPC) {
 		msk->can_ack = true;
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index f0bd2e17f2d6..21bb248a2c82 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -286,6 +286,7 @@ struct mptcp_sock {
 	struct socket	*subflow; /* outgoing connect/listener/!mp_capable */
 	struct sock	*first;
 	struct mptcp_pm_data	pm;
+	struct mptcp_sched_ops	*sched;
 	struct {
 		u32	space;	/* bytes copied in last measurement window */
 		u32	copied; /* bytes copied in this measurement window */
@@ -609,6 +610,9 @@ void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
 struct mptcp_sched_ops *mptcp_sched_find(const char *name);
 int mptcp_register_scheduler(struct mptcp_sched_ops *sched);
 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched);
+void mptcp_init_sched(struct mptcp_sock *msk,
+		      struct mptcp_sched_ops *sched);
+void mptcp_release_sched(struct mptcp_sock *msk);
 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk);
 void mptcp_sched_init(void);
 
diff --git a/net/mptcp/sched.c b/net/mptcp/sched.c
index 331e6517622a..c1a4c5170b8d 100644
--- a/net/mptcp/sched.c
+++ b/net/mptcp/sched.c
@@ -54,6 +54,26 @@ void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched)
 	synchronize_rcu();
 }
 
+void mptcp_init_sched(struct mptcp_sock *msk,
+		      struct mptcp_sched_ops *sched)
+{
+	if (!sched)
+		return;
+
+	msk->sched = sched;
+	if (msk->sched->init)
+		msk->sched->init(msk);
+
+	pr_debug("sched=%s", msk->sched->name);
+}
+
+void mptcp_release_sched(struct mptcp_sock *msk)
+{
+	if (msk->sched->release)
+		msk->sched->release(msk);
+	msk->sched = NULL;
+}
+
 static struct mptcp_sched_ops mptcp_sched_default = {
 	.get_subflow    = mptcp_subflow_get_send,
 	.name           = "default",
-- 
2.34.1