Re: [PATCH net] sctp: get netns from asoc and ep base
From: Xin Long <lucien.xin@gmail.com>
Date: 2019-11-26 08:27:43
Also in:
linux-sctp
On Mon, Nov 25, 2019 at 9:24 PM Neil Horman [off-list ref] wrote:
On Mon, Nov 25, 2019 at 11:59:50AM +0800, Xin Long wrote:quoted
Commit 312434617cb1 ("sctp: cache netns in sctp_ep_common") set netns in asoc and ep base since they're created, and it will never change. It's a better way to get netns from asoc and ep base, comparing to calling sock_net(). This patch is to replace them.I don't see anything expressly wrong with this, but I'm not sure I see it as better either. It makes things more consistent with commit 312434617cb1, sure, but both sock_net, and its called read_pnet are both static inline functions, so it should reduce to the same thing. In fact, I think it may be better to ammend the fix from 312434617cb1, to, instead of caching the net structure in the ep_common struct, instead, update sctp_assoc_migrate so that the new value base.sk is atomically exchanged before any calls to sock_put/sock_hold are made, so that the rhashtable lookup is consistent. That would allow us to consistently use sock_net the way other protocols do
why is "before any calls to sock_put/sock_hold are made"? I was thinking to use rcu_assign_pointer() and rcu_dereference() for base.sk, but looks troublesome to replace all places. do you think it would work for atomic exchange? or you have some better idea?
Neilquoted
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> --- net/sctp/associola.c | 10 +++++----- net/sctp/chunk.c | 2 +- net/sctp/endpointola.c | 6 +++--- net/sctp/input.c | 5 ++--- net/sctp/output.c | 2 +- net/sctp/outqueue.c | 6 +++--- net/sctp/sm_make_chunk.c | 7 +++---- net/sctp/sm_sideeffect.c | 16 ++++++---------- net/sctp/sm_statefuns.c | 2 +- net/sctp/socket.c | 12 +++++------- net/sctp/stream.c | 3 +-- net/sctp/stream_interleave.c | 23 ++++++++++------------- net/sctp/transport.c | 2 +- net/sctp/ulpqueue.c | 15 +++++++-------- 14 files changed, 49 insertions(+), 62 deletions(-)diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 41839b8..a725f53 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c@@ -579,7 +579,6 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, const gfp_t gfp, const int peer_state) { - struct net *net = sock_net(asoc->base.sk); struct sctp_transport *peer; struct sctp_sock *sp; unsigned short port;@@ -609,7 +608,7 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, return peer; } - peer = sctp_transport_new(net, addr, gfp); + peer = sctp_transport_new(asoc->base.net, addr, gfp); if (!peer) return NULL;@@ -978,7 +977,7 @@ static void sctp_assoc_bh_rcv(struct work_struct *work) struct sctp_association *asoc = container_of(work, struct sctp_association, base.inqueue.immediate); - struct net *net = sock_net(asoc->base.sk); + struct net *net = asoc->base.net; union sctp_subtype subtype; struct sctp_endpoint *ep; struct sctp_chunk *chunk;@@ -1446,7 +1445,8 @@ void sctp_assoc_sync_pmtu(struct sctp_association *asoc) /* Should we send a SACK to update our peer? */ static inline bool sctp_peer_needs_update(struct sctp_association *asoc) { - struct net *net = sock_net(asoc->base.sk); + struct net *net = asoc->base.net; + switch (asoc->state) { case SCTP_STATE_ESTABLISHED: case SCTP_STATE_SHUTDOWN_PENDING:@@ -1580,7 +1580,7 @@ int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, if (asoc->peer.ipv6_address) flags |= SCTP_ADDR6_PEERSUPP; - return sctp_bind_addr_copy(sock_net(asoc->base.sk), + return sctp_bind_addr_copy(asoc->base.net, &asoc->base.bind_addr, &asoc->ep->base.bind_addr, scope, gfp, flags);diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c index cc0405c..064675b 100644 --- a/net/sctp/chunk.c +++ b/net/sctp/chunk.c@@ -227,7 +227,7 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc, if (msg_len >= first_len) { msg->can_delay = 0; if (msg_len > first_len) - SCTP_INC_STATS(sock_net(asoc->base.sk), + SCTP_INC_STATS(asoc->base.net, SCTP_MIB_FRAGUSRMSGS); } else { /* Which may be the only one... */diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c index 3067deb..6e7e0d3 100644 --- a/net/sctp/endpointola.c +++ b/net/sctp/endpointola.c@@ -244,7 +244,7 @@ struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, struct sctp_endpoint *retval = NULL; if ((htons(ep->base.bind_addr.port) == laddr->v4.sin_port) && - net_eq(sock_net(ep->base.sk), net)) { + net_eq(ep->base.net, net)) { if (sctp_bind_addr_match(&ep->base.bind_addr, laddr, sctp_sk(ep->base.sk))) retval = ep;@@ -292,8 +292,8 @@ bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, const union sctp_addr *paddr) { struct sctp_sockaddr_entry *addr; + struct net *net = ep->base.net; struct sctp_bind_addr *bp; - struct net *net = sock_net(ep->base.sk); bp = &ep->base.bind_addr; /* This function is called with the socket lock held,@@ -384,7 +384,7 @@ static void sctp_endpoint_bh_rcv(struct work_struct *work) if (asoc && sctp_chunk_is_data(chunk)) asoc->peer.last_data_from = chunk->transport; else { - SCTP_INC_STATS(sock_net(ep->base.sk), SCTP_MIB_INCTRLCHUNKS); + SCTP_INC_STATS(ep->base.net, SCTP_MIB_INCTRLCHUNKS); if (asoc) asoc->stats.ictrlchunks++; }diff --git a/net/sctp/input.c b/net/sctp/input.c index 4d2bcfc..efaaefc 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c@@ -937,7 +937,7 @@ int sctp_hash_transport(struct sctp_transport *t) if (t->asoc->temp) return 0; - arg.net = sock_net(t->asoc->base.sk); + arg.net = t->asoc->base.net; arg.paddr = &t->ipaddr; arg.lport = htons(t->asoc->base.bind_addr.port);@@ -1004,12 +1004,11 @@ struct sctp_transport *sctp_epaddr_lookup_transport( const struct sctp_endpoint *ep, const union sctp_addr *paddr) { - struct net *net = sock_net(ep->base.sk); struct rhlist_head *tmp, *list; struct sctp_transport *t; struct sctp_hash_cmp_arg arg = { .paddr = paddr, - .net = net, + .net = ep->base.net, .lport = htons(ep->base.bind_addr.port), };diff --git a/net/sctp/output.c b/net/sctp/output.c index dbda7e7..1441eaf 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c@@ -282,7 +282,7 @@ static enum sctp_xmit sctp_packet_bundle_sack(struct sctp_packet *pkt, sctp_chunk_free(sack); goto out; } - SCTP_INC_STATS(sock_net(asoc->base.sk), + SCTP_INC_STATS(asoc->base.net, SCTP_MIB_OUTCTRLCHUNKS); asoc->stats.octrlchunks++; asoc->peer.sack_needed = 0;diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 0dab62b..a031d11 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c@@ -279,7 +279,7 @@ void sctp_outq_free(struct sctp_outq *q) /* Put a new chunk in an sctp_outq. */ void sctp_outq_tail(struct sctp_outq *q, struct sctp_chunk *chunk, gfp_t gfp) { - struct net *net = sock_net(q->asoc->base.sk); + struct net *net = q->asoc->base.net; pr_debug("%s: outq:%p, chunk:%p[%s]\n", __func__, q, chunk, chunk && chunk->chunk_hdr ?@@ -533,7 +533,7 @@ void sctp_retransmit_mark(struct sctp_outq *q, void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, enum sctp_retransmit_reason reason) { - struct net *net = sock_net(q->asoc->base.sk); + struct net *net = q->asoc->base.net; switch (reason) { case SCTP_RTXR_T3_RTX:@@ -1884,6 +1884,6 @@ void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 ctsn) if (ftsn_chunk) { list_add_tail(&ftsn_chunk->list, &q->control_chunk_list); - SCTP_INC_STATS(sock_net(asoc->base.sk), SCTP_MIB_OUTCTRLCHUNKS); + SCTP_INC_STATS(asoc->base.net, SCTP_MIB_OUTCTRLCHUNKS); } }diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index 48d6395..09050c1 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c@@ -2307,7 +2307,6 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk, const union sctp_addr *peer_addr, struct sctp_init_chunk *peer_init, gfp_t gfp) { - struct net *net = sock_net(asoc->base.sk); struct sctp_transport *transport; struct list_head *pos, *temp; union sctp_params param;@@ -2363,8 +2362,8 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk, * also give us an option to silently ignore the packet, which * is what we'll do here. */ - if (!net->sctp.addip_noauth && - (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) { + if (!asoc->base.net->sctp.addip_noauth && + (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) { asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP | SCTP_PARAM_DEL_IP | SCTP_PARAM_SET_PRIMARY);@@ -2491,9 +2490,9 @@ static int sctp_process_param(struct sctp_association *asoc, const union sctp_addr *peer_addr, gfp_t gfp) { - struct net *net = sock_net(asoc->base.sk); struct sctp_endpoint *ep = asoc->ep; union sctp_addr_param *addr_param; + struct net *net = asoc->base.net; struct sctp_transport *t; enum sctp_scope scope; union sctp_addr addr;diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index e52b212..20b0281 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c@@ -516,8 +516,6 @@ static void sctp_do_8_2_transport_strike(struct sctp_cmd_seq *commands, struct sctp_transport *transport, int is_hb) { - struct net *net = sock_net(asoc->base.sk); - /* The check for association's overall error counter exceeding the * threshold is done in the state function. */@@ -544,10 +542,10 @@ static void sctp_do_8_2_transport_strike(struct sctp_cmd_seq *commands, * is SCTP_ACTIVE, then mark this transport as Partially Failed, * see SCTP Quick Failover Draft, section 5.1 */ - if (net->sctp.pf_enable && - (transport->state == SCTP_ACTIVE) && - (transport->error_count < transport->pathmaxrxt) && - (transport->error_count > transport->pf_retrans)) { + if (asoc->base.net->sctp.pf_enable && + transport->state == SCTP_ACTIVE && + transport->error_count < transport->pathmaxrxt && + transport->error_count > transport->pf_retrans) { sctp_assoc_control_transport(asoc, transport, SCTP_TRANSPORT_PF,@@ -793,10 +791,8 @@ static int sctp_cmd_process_sack(struct sctp_cmd_seq *cmds, int err = 0; if (sctp_outq_sack(&asoc->outqueue, chunk)) { - struct net *net = sock_net(asoc->base.sk); - /* There are no more TSNs awaiting SACK. */ - err = sctp_do_sm(net, SCTP_EVENT_T_OTHER, + err = sctp_do_sm(asoc->base.net, SCTP_EVENT_T_OTHER, SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), asoc->state, asoc->ep, asoc, NULL, GFP_ATOMIC);@@ -829,7 +825,7 @@ static void sctp_cmd_assoc_update(struct sctp_cmd_seq *cmds, struct sctp_association *asoc, struct sctp_association *new) { - struct net *net = sock_net(asoc->base.sk); + struct net *net = asoc->base.net; struct sctp_chunk *abort; if (!sctp_assoc_update(asoc, new))diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 4ab8208..42558fa 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c@@ -1320,7 +1320,7 @@ static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, struct sctp_chunk *init, struct sctp_cmd_seq *commands) { - struct net *net = sock_net(new_asoc->base.sk); + struct net *net = new_asoc->base.net; struct sctp_transport *new_addr; int ret = 1;diff --git a/net/sctp/socket.c b/net/sctp/socket.c index ffd3262..5e0efbc 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c@@ -436,8 +436,7 @@ static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len) static int sctp_send_asconf(struct sctp_association *asoc, struct sctp_chunk *chunk) { - struct net *net = sock_net(asoc->base.sk); - int retval = 0; + int retval = 0; /* If there is an outstanding ASCONF chunk, queue it for later * transmission.@@ -449,7 +448,7 @@ static int sctp_send_asconf(struct sctp_association *asoc, /* Hold the chunk until an ASCONF_ACK is received. */ sctp_chunk_hold(chunk); - retval = sctp_primitive_ASCONF(net, asoc, chunk); + retval = sctp_primitive_ASCONF(asoc->base.net, asoc, chunk); if (retval) sctp_chunk_free(chunk); else@@ -2428,9 +2427,8 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params, int error; if (params->spp_flags & SPP_HB_DEMAND && trans) { - struct net *net = sock_net(trans->asoc->base.sk); - - error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans); + error = sctp_primitive_REQUESTHEARTBEAT(trans->asoc->base.net, + trans->asoc, trans); if (error) return error; }@@ -5308,7 +5306,7 @@ struct sctp_transport *sctp_transport_get_next(struct net *net, if (!sctp_transport_hold(t)) continue; - if (net_eq(sock_net(t->asoc->base.sk), net) && + if (net_eq(t->asoc->base.net, net) && t->asoc->peer.primary_path == t) break;diff --git a/net/sctp/stream.c b/net/sctp/stream.c index e83cdaa..df60b5e 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c@@ -218,10 +218,9 @@ void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new) static int sctp_send_reconf(struct sctp_association *asoc, struct sctp_chunk *chunk) { - struct net *net = sock_net(asoc->base.sk); int retval = 0; - retval = sctp_primitive_RECONF(net, asoc, chunk); + retval = sctp_primitive_RECONF(asoc->base.net, asoc, chunk); if (retval) sctp_chunk_free(chunk);diff --git a/net/sctp/stream_interleave.c b/net/sctp/stream_interleave.c index 40c40be..6b13f73 100644 --- a/net/sctp/stream_interleave.c +++ b/net/sctp/stream_interleave.c@@ -241,9 +241,8 @@ static struct sctp_ulpevent *sctp_intl_retrieve_partial( if (!first_frag) return NULL; - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), - &ulpq->reasm, first_frag, - last_frag); + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm, + first_frag, last_frag); if (retval) { sin->fsn = next_fsn; if (is_last) {@@ -326,7 +325,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_reassembled( pd_point = sctp_sk(asoc->base.sk)->pd_point; if (pd_point && pd_point <= pd_len) { - retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), + retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm, pd_first, pd_last); if (retval) {@@ -337,8 +336,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_reassembled( goto out; found: - retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), - &ulpq->reasm, + retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm, first_frag, pos); if (retval) retval->msg_flags |= MSG_EOR;@@ -630,7 +628,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_partial_uo( if (!first_frag) return NULL; - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm_uo, first_frag, last_frag); if (retval) {@@ -716,7 +714,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_reassembled_uo( pd_point = sctp_sk(asoc->base.sk)->pd_point; if (pd_point && pd_point <= pd_len) { - retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), + retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm_uo, pd_first, pd_last); if (retval) {@@ -727,8 +725,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_reassembled_uo( goto out; found: - retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), - &ulpq->reasm_uo, + retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm_uo, first_frag, pos); if (retval) retval->msg_flags |= MSG_EOR;@@ -814,7 +811,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_first_uo(struct sctp_ulpq *ulpq) return NULL; out: - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm_uo, first_frag, last_frag); if (retval) {@@ -921,7 +918,7 @@ static struct sctp_ulpevent *sctp_intl_retrieve_first(struct sctp_ulpq *ulpq) return NULL; out: - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm, first_frag, last_frag); if (retval) {@@ -1159,7 +1156,7 @@ static void sctp_generate_iftsn(struct sctp_outq *q, __u32 ctsn) if (ftsn_chunk) { list_add_tail(&ftsn_chunk->list, &q->control_chunk_list); - SCTP_INC_STATS(sock_net(asoc->base.sk), SCTP_MIB_OUTCTRLCHUNKS); + SCTP_INC_STATS(asoc->base.net, SCTP_MIB_OUTCTRLCHUNKS); } }diff --git a/net/sctp/transport.c b/net/sctp/transport.c index 7235a60..f4de064 100644 --- a/net/sctp/transport.c +++ b/net/sctp/transport.c@@ -334,7 +334,7 @@ void sctp_transport_update_rto(struct sctp_transport *tp, __u32 rtt) pr_debug("%s: rto_pending not set on transport %p!\n", __func__, tp); if (tp->rttvar || tp->srtt) { - struct net *net = sock_net(tp->asoc->base.sk); + struct net *net = tp->asoc->base.net; /* 6.3.1 C3) When a new RTT measurement R' is made, set * RTTVAR <- (1 - RTO.Beta) * RTTVAR + RTO.Beta * |SRTT - R'| * SRTT <- (1 - RTO.Alpha) * SRTT + RTO.Alpha * R'diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c index b6536b7..1c6c640 100644 --- a/net/sctp/ulpqueue.c +++ b/net/sctp/ulpqueue.c@@ -486,10 +486,9 @@ static struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ul cevent = sctp_skb2event(pd_first); pd_point = sctp_sk(asoc->base.sk)->pd_point; if (pd_point && pd_point <= pd_len) { - retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), + retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm, - pd_first, - pd_last); + pd_first, pd_last); if (retval) sctp_ulpq_set_pd(ulpq); }@@ -497,7 +496,7 @@ static struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ul done: return retval; found: - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm, first_frag, pos); if (retval) retval->msg_flags |= MSG_EOR;@@ -563,8 +562,8 @@ static struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq *ulpq) * further. */ done: - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), - &ulpq->reasm, first_frag, last_frag); + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm, + first_frag, last_frag); if (retval && is_last) retval->msg_flags |= MSG_EOR;@@ -664,8 +663,8 @@ static struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *ulpq) * further. */ done: - retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), - &ulpq->reasm, first_frag, last_frag); + retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm, + first_frag, last_frag); return retval; } --2.1.0