Commit 47faa1e4 authored by Xin Long's avatar Xin Long Committed by David S. Miller
Browse files

sctp: remove the dead field of sctp_transport 



After we use refcnt to check if transport is alive, the dead can be
removed from sctp_transport.

The traversal of transport_addr_list in procfs dump is using
list_for_each_entry_rcu, no need to check if it has been freed.

sctp_generate_t3_rtx_event and sctp_generate_heartbeat_event is
protected by sock lock, it's not necessary to check dead, either.
also, the timers are cancelled when sctp_transport_free() is
called, that it doesn't wait for refcnt to reach 0 to cancel them.

Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fba4c330

include/net/sctp/structs.h

+1 −2
Original line number Diff line number Diff line
@@ -756,7 +756,6 @@ struct sctp_transport { 


	/* Reference counting. */

	atomic_t refcnt;

	__u32	 dead:1,

		/* RTO-Pending : A flag used to track if one of the DATA

		 *		chunks sent to this address is currently being

		 *		used to compute a RTT. If this flag is 0,
@@ -766,7 +765,7 @@ struct sctp_transport { 
		 *		calculation completes (i.e. the DATA chunk

		 *		is SACK'd) clear this flag.

		 */

		 rto_pending:1,

	__u32	rto_pending:1,



		/*

		 * hb_sent : a flag that signals that we have a pending

net/sctp/proc.c

+0 −4
Original line number Diff line number Diff line
@@ -165,8 +165,6 @@ static void sctp_seq_dump_remote_addrs(struct seq_file *seq, struct sctp_associa 
	list_for_each_entry_rcu(transport, &assoc->peer.transport_addr_list,

			transports) {

		addr = &transport->ipaddr;

		if (transport->dead)

			continue;



		af = sctp_get_af_specific(addr->sa.sa_family);

		if (af->cmp_addr(addr, primary)) {
@@ -499,8 +497,6 @@ static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) 


	list_for_each_entry_rcu(tsp, &assoc->peer.transport_addr_list,

				transports) {

		if (tsp->dead)

			continue;

		/*

		 * The remote address (ADDR)

		 */

net/sctp/sm_sideeffect.c

+0 −12
Original line number Diff line number Diff line
@@ -259,12 +259,6 @@ void sctp_generate_t3_rtx_event(unsigned long peer) 
		goto out_unlock;

	}



	/* Is this transport really dead and just waiting around for

	 * the timer to let go of the reference?

	 */

	if (transport->dead)

		goto out_unlock;



	/* Run through the state machine.  */

	error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,

			   SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
@@ -380,12 +374,6 @@ void sctp_generate_heartbeat_event(unsigned long data) 
		goto out_unlock;

	}



	/* Is this structure just waiting around for us to actually

	 * get destroyed?

	 */

	if (transport->dead)

		goto out_unlock;



	error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,

			   SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),

			   asoc->state, asoc->ep, asoc,

net/sctp/transport.c

+1 −3
Original line number Diff line number Diff line
@@ -132,8 +132,6 @@ fail: 
 */

void sctp_transport_free(struct sctp_transport *transport)

{

	transport->dead = 1;



	/* Try to delete the heartbeat timer.  */

	if (del_timer(&transport->hb_timer))

		sctp_transport_put(transport);
@@ -169,7 +167,7 @@ static void sctp_transport_destroy_rcu(struct rcu_head *head) 
 */

static void sctp_transport_destroy(struct sctp_transport *transport)

{

	if (unlikely(!transport->dead)) {

	if (unlikely(atomic_read(&transport->refcnt))) {

		WARN(1, "Attempt to destroy undead transport %p!\n", transport);

		return;

	}

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