From 4d99b2581effe115376402e710fbcb1c3c073769 Mon Sep 17 00:00:00 2001 From: Liang Zhen Date: Wed, 2 Mar 2016 18:53:29 -0500 Subject: [PATCH] staging: lustre: avoid intensive reconnecting for ko2iblnd When there is a connection race between two nodes and one side of the connection is rejected by the other side. o2iblnd will reconnect immediately, this is going to generate a lot of trashes if: - race winner is slow and can't send out connecting request in short time. - remote side leaves a cmid in TIMEWAIT state, which will reject future connection requests To resolve this problem, this patch changed the reconnection behave: reconnection is submitted by connd only if a zombie connection is being destroyed and there is a pending reconnection request for the corresponding peer. Also, after a few rejections, reconnection will have a time interval between each attempt. Signed-off-by: Liang Zhen Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-7569 Reviewed-on: http://review.whamcloud.com/17892 Reviewed-by: Doug Oucharek Reviewed-by: James Simmons Tested-by: James Simmons Reviewed-by: Oleg Drokin Signed-off-by: Greg Kroah-Hartman --- .../lustre/lnet/klnds/o2iblnd/o2iblnd.c | 40 +-- .../lustre/lnet/klnds/o2iblnd/o2iblnd.h | 54 +++- .../lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c | 280 +++++++++++++----- 3 files changed, 258 insertions(+), 116 deletions(-) diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c index 56c221b2731f..135ccf18917b 100644 --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c @@ -364,9 +364,7 @@ void kiblnd_destroy_peer(kib_peer_t *peer) LASSERT(net); LASSERT(!atomic_read(&peer->ibp_refcount)); LASSERT(!kiblnd_peer_active(peer)); - LASSERT(!peer->ibp_connecting); - LASSERT(!peer->ibp_accepting); - LASSERT(list_empty(&peer->ibp_conns)); + LASSERT(kiblnd_peer_idle(peer)); LASSERT(list_empty(&peer->ibp_tx_queue)); LIBCFS_FREE(peer, sizeof(*peer)); @@ -392,10 +390,7 @@ kib_peer_t *kiblnd_find_peer_locked(lnet_nid_t nid) list_for_each(tmp, peer_list) { peer = list_entry(tmp, kib_peer_t, ibp_list); - - LASSERT(peer->ibp_connecting > 0 || /* creating conns */ - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); /* active conn */ + LASSERT(!kiblnd_peer_idle(peer)); if (peer->ibp_nid != nid) continue; @@ -432,9 +427,7 @@ static int kiblnd_get_peer_info(lnet_ni_t *ni, int index, for (i = 0; i < kiblnd_data.kib_peer_hash_size; i++) { list_for_each(ptmp, &kiblnd_data.kib_peers[i]) { peer = list_entry(ptmp, kib_peer_t, ibp_list); - LASSERT(peer->ibp_connecting > 0 || - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); + LASSERT(!kiblnd_peer_idle(peer)); if (peer->ibp_ni != ni) continue; @@ -502,9 +495,7 @@ static int kiblnd_del_peer(lnet_ni_t *ni, lnet_nid_t nid) for (i = lo; i <= hi; i++) { list_for_each_safe(ptmp, pnxt, &kiblnd_data.kib_peers[i]) { peer = list_entry(ptmp, kib_peer_t, ibp_list); - LASSERT(peer->ibp_connecting > 0 || - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); + LASSERT(!kiblnd_peer_idle(peer)); if (peer->ibp_ni != ni) continue; @@ -545,9 +536,7 @@ static kib_conn_t *kiblnd_get_conn_by_idx(lnet_ni_t *ni, int index) for (i = 0; i < kiblnd_data.kib_peer_hash_size; i++) { list_for_each(ptmp, &kiblnd_data.kib_peers[i]) { peer = list_entry(ptmp, kib_peer_t, ibp_list); - LASSERT(peer->ibp_connecting > 0 || - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); + LASSERT(!kiblnd_peer_idle(peer)); if (peer->ibp_ni != ni) continue; @@ -837,14 +826,14 @@ kib_conn_t *kiblnd_create_conn(kib_peer_t *peer, struct rdma_cm_id *cmid, return conn; failed_2: - kiblnd_destroy_conn(conn); + kiblnd_destroy_conn(conn, true); failed_1: LIBCFS_FREE(init_qp_attr, sizeof(*init_qp_attr)); failed_0: return NULL; } -void kiblnd_destroy_conn(kib_conn_t *conn) +void kiblnd_destroy_conn(kib_conn_t *conn, bool free_conn) { struct rdma_cm_id *cmid = conn->ibc_cmid; kib_peer_t *peer = conn->ibc_peer; @@ -984,9 +973,7 @@ static int kiblnd_close_matching_conns(lnet_ni_t *ni, lnet_nid_t nid) for (i = lo; i <= hi; i++) { list_for_each_safe(ptmp, pnxt, &kiblnd_data.kib_peers[i]) { peer = list_entry(ptmp, kib_peer_t, ibp_list); - LASSERT(peer->ibp_connecting > 0 || - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); + LASSERT(!kiblnd_peer_idle(peer)); if (peer->ibp_ni != ni) continue; @@ -1071,12 +1058,8 @@ static void kiblnd_query(lnet_ni_t *ni, lnet_nid_t nid, unsigned long *when) read_lock_irqsave(glock, flags); peer = kiblnd_find_peer_locked(nid); - if (peer) { - LASSERT(peer->ibp_connecting > 0 || /* creating conns */ - peer->ibp_accepting > 0 || - !list_empty(&peer->ibp_conns)); /* active conn */ + if (peer) last_alive = peer->ibp_last_alive; - } read_unlock_irqrestore(glock, flags); @@ -2368,6 +2351,8 @@ static void kiblnd_base_shutdown(void) LASSERT(list_empty(&kiblnd_data.kib_peers[i])); LASSERT(list_empty(&kiblnd_data.kib_connd_zombies)); LASSERT(list_empty(&kiblnd_data.kib_connd_conns)); + LASSERT(list_empty(&kiblnd_data.kib_reconn_list)); + LASSERT(list_empty(&kiblnd_data.kib_reconn_wait)); /* flag threads to terminate; wake and wait for them to die */ kiblnd_data.kib_shutdown = 1; @@ -2506,6 +2491,9 @@ static int kiblnd_base_startup(void) spin_lock_init(&kiblnd_data.kib_connd_lock); INIT_LIST_HEAD(&kiblnd_data.kib_connd_conns); INIT_LIST_HEAD(&kiblnd_data.kib_connd_zombies); + INIT_LIST_HEAD(&kiblnd_data.kib_reconn_list); + INIT_LIST_HEAD(&kiblnd_data.kib_reconn_wait); + init_waitqueue_head(&kiblnd_data.kib_connd_waitq); init_waitqueue_head(&kiblnd_data.kib_failover_waitq); diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h index 6a4c4aceff40..bfcbdd167da7 100644 --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h @@ -348,6 +348,16 @@ typedef struct { void *kib_connd; /* the connd task (serialisation assertions) */ struct list_head kib_connd_conns; /* connections to setup/teardown */ struct list_head kib_connd_zombies; /* connections with zero refcount */ + /* connections to reconnect */ + struct list_head kib_reconn_list; + /* peers wait for reconnection */ + struct list_head kib_reconn_wait; + /** + * The second that peers are pulled out from \a kib_reconn_wait + * for reconnection. + */ + time64_t kib_reconn_sec; + wait_queue_head_t kib_connd_waitq; /* connection daemon sleeps here */ spinlock_t kib_connd_lock; /* serialise */ struct ib_qp_attr kib_error_qpa; /* QP->ERROR */ @@ -525,6 +535,8 @@ typedef struct kib_conn { struct list_head ibc_list; /* stash on peer's conn list */ struct list_head ibc_sched_list; /* schedule for attention */ __u16 ibc_version; /* version of connection */ + /* reconnect later */ + __u16 ibc_reconnect:1; __u64 ibc_incarnation; /* which instance of the peer */ atomic_t ibc_refcount; /* # users */ int ibc_state; /* what's happening */ @@ -574,18 +586,25 @@ typedef struct kib_peer { struct list_head ibp_list; /* stash on global peer list */ lnet_nid_t ibp_nid; /* who's on the other end(s) */ lnet_ni_t *ibp_ni; /* LNet interface */ - atomic_t ibp_refcount; /* # users */ struct list_head ibp_conns; /* all active connections */ struct list_head ibp_tx_queue; /* msgs waiting for a conn */ - __u16 ibp_version; /* version of peer */ __u64 ibp_incarnation; /* incarnation of peer */ - int ibp_connecting; /* current active connection attempts - */ - int ibp_accepting; /* current passive connection attempts - */ - int ibp_error; /* errno on closing this peer */ - unsigned long ibp_last_alive; /* when (in jiffies) I was last alive - */ + /* when (in jiffies) I was last alive */ + unsigned long ibp_last_alive; + /* # users */ + atomic_t ibp_refcount; + /* version of peer */ + __u16 ibp_version; + /* current passive connection attempts */ + unsigned short ibp_accepting; + /* current active connection attempts */ + unsigned short ibp_connecting; + /* reconnect this peer later */ + unsigned short ibp_reconnecting:1; + /* # consecutive reconnection attempts to this peer */ + unsigned int ibp_reconnected; + /* errno on closing this peer */ + int ibp_error; /* max map_on_demand */ __u16 ibp_max_frags; /* max_peer_credits */ @@ -667,6 +686,20 @@ do { \ kiblnd_destroy_peer(peer); \ } while (0) +static inline bool +kiblnd_peer_connecting(kib_peer_t *peer) +{ + return peer->ibp_connecting || + peer->ibp_reconnecting || + peer->ibp_accepting; +} + +static inline bool +kiblnd_peer_idle(kib_peer_t *peer) +{ + return !kiblnd_peer_connecting(peer) && list_empty(&peer->ibp_conns); +} + static inline struct list_head * kiblnd_nid2peerlist(lnet_nid_t nid) { @@ -943,6 +976,7 @@ int kiblnd_translate_mtu(int value); int kiblnd_dev_failover(kib_dev_t *dev); int kiblnd_create_peer(lnet_ni_t *ni, kib_peer_t **peerp, lnet_nid_t nid); void kiblnd_destroy_peer(kib_peer_t *peer); +bool kiblnd_reconnect_peer(kib_peer_t *peer); void kiblnd_destroy_dev(kib_dev_t *dev); void kiblnd_unlink_peer_locked(kib_peer_t *peer); kib_peer_t *kiblnd_find_peer_locked(lnet_nid_t nid); @@ -952,7 +986,7 @@ int kiblnd_close_peer_conns_locked(kib_peer_t *peer, int why); kib_conn_t *kiblnd_create_conn(kib_peer_t *peer, struct rdma_cm_id *cmid, int state, int version); -void kiblnd_destroy_conn(kib_conn_t *conn); +void kiblnd_destroy_conn(kib_conn_t *conn, bool free_conn); void kiblnd_close_conn(kib_conn_t *conn, int error); void kiblnd_close_conn_locked(kib_conn_t *conn, int error); diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c index 199c1057a0aa..79051c02ab3a 100644 --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c @@ -1257,6 +1257,7 @@ kiblnd_connect_peer(kib_peer_t *peer) LASSERT(net); LASSERT(peer->ibp_connecting > 0); + LASSERT(!peer->ibp_reconnecting); cmid = kiblnd_rdma_create_id(kiblnd_cm_callback, peer, RDMA_PS_TCP, IB_QPT_RC); @@ -1312,6 +1313,56 @@ kiblnd_connect_peer(kib_peer_t *peer) kiblnd_peer_connect_failed(peer, 1, rc); } +bool +kiblnd_reconnect_peer(kib_peer_t *peer) +{ + rwlock_t *glock = &kiblnd_data.kib_global_lock; + char *reason = NULL; + struct list_head txs; + unsigned long flags; + + INIT_LIST_HEAD(&txs); + + write_lock_irqsave(glock, flags); + if (!peer->ibp_reconnecting) { + if (peer->ibp_accepting) + reason = "accepting"; + else if (peer->ibp_connecting) + reason = "connecting"; + else if (!list_empty(&peer->ibp_conns)) + reason = "connected"; + else /* connected then closed */ + reason = "closed"; + + goto no_reconnect; + } + + LASSERT(!peer->ibp_accepting && !peer->ibp_connecting && + list_empty(&peer->ibp_conns)); + peer->ibp_reconnecting = 0; + + if (!kiblnd_peer_active(peer)) { + list_splice_init(&peer->ibp_tx_queue, &txs); + reason = "unlinked"; + goto no_reconnect; + } + + peer->ibp_connecting++; + peer->ibp_reconnected++; + write_unlock_irqrestore(glock, flags); + + kiblnd_connect_peer(peer); + return true; + +no_reconnect: + write_unlock_irqrestore(glock, flags); + + CWARN("Abort reconnection of %s: %s\n", + libcfs_nid2str(peer->ibp_nid), reason); + kiblnd_txlist_done(peer->ibp_ni, &txs, -ECONNABORTED); + return false; +} + void kiblnd_launch_tx(lnet_ni_t *ni, kib_tx_t *tx, lnet_nid_t nid) { @@ -1357,8 +1408,7 @@ kiblnd_launch_tx(lnet_ni_t *ni, kib_tx_t *tx, lnet_nid_t nid) if (peer) { if (list_empty(&peer->ibp_conns)) { /* found a peer, but it's still connecting... */ - LASSERT(peer->ibp_connecting || - peer->ibp_accepting); + LASSERT(kiblnd_peer_connecting(peer)); if (tx) list_add_tail(&tx->tx_list, &peer->ibp_tx_queue); @@ -1396,8 +1446,7 @@ kiblnd_launch_tx(lnet_ni_t *ni, kib_tx_t *tx, lnet_nid_t nid) if (peer2) { if (list_empty(&peer2->ibp_conns)) { /* found a peer, but it's still connecting... */ - LASSERT(peer2->ibp_connecting || - peer2->ibp_accepting); + LASSERT(kiblnd_peer_connecting(peer2)); if (tx) list_add_tail(&tx->tx_list, &peer2->ibp_tx_queue); @@ -1817,10 +1866,7 @@ kiblnd_peer_notify(kib_peer_t *peer) read_lock_irqsave(&kiblnd_data.kib_global_lock, flags); - if (list_empty(&peer->ibp_conns) && - !peer->ibp_accepting && - !peer->ibp_connecting && - peer->ibp_error) { + if (kiblnd_peer_idle(peer) && peer->ibp_error) { error = peer->ibp_error; peer->ibp_error = 0; @@ -2020,14 +2066,14 @@ kiblnd_peer_connect_failed(kib_peer_t *peer, int active, int error) peer->ibp_accepting--; } - if (peer->ibp_connecting || - peer->ibp_accepting) { + if (kiblnd_peer_connecting(peer)) { /* another connection attempt under way... */ write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags); return; } + peer->ibp_reconnected = 0; if (list_empty(&peer->ibp_conns)) { /* Take peer's blocked transmits to complete with error */ list_add(&zombies, &peer->ibp_tx_queue); @@ -2100,6 +2146,7 @@ kiblnd_connreq_done(kib_conn_t *conn, int status) */ kiblnd_conn_addref(conn); /* +1 ref for ibc_list */ list_add(&conn->ibc_list, &peer->ibp_conns); + peer->ibp_reconnected = 0; if (active) peer->ibp_connecting--; else @@ -2355,10 +2402,16 @@ kiblnd_passive_connect(struct rdma_cm_id *cmid, void *priv, int priv_nob) if (peer2->ibp_incarnation != reqmsg->ibm_srcstamp || peer2->ibp_version != version) { kiblnd_close_peer_conns_locked(peer2, -ESTALE); + + if (kiblnd_peer_active(peer2)) { + peer2->ibp_incarnation = reqmsg->ibm_srcstamp; + peer2->ibp_version = version; + } write_unlock_irqrestore(g_lock, flags); - CWARN("Conn stale %s [old ver: %x, new ver: %x]\n", - libcfs_nid2str(nid), peer2->ibp_version, version); + CWARN("Conn stale %s version %x/%x incarnation %llu/%llu\n", + libcfs_nid2str(nid), peer2->ibp_version, version, + peer2->ibp_incarnation, reqmsg->ibm_srcstamp); kiblnd_peer_decref(peer); rej.ibr_why = IBLND_REJECT_CONN_STALE; @@ -2377,6 +2430,11 @@ kiblnd_passive_connect(struct rdma_cm_id *cmid, void *priv, int priv_nob) goto failed; } + /** + * passive connection is allowed even this peer is waiting for + * reconnection. + */ + peer2->ibp_reconnecting = 0; peer2->ibp_accepting++; kiblnd_peer_addref(peer2); @@ -2478,75 +2536,79 @@ kiblnd_passive_connect(struct rdma_cm_id *cmid, void *priv, int priv_nob) } static void -kiblnd_reconnect(kib_conn_t *conn, int version, - __u64 incarnation, int why, kib_connparams_t *cp) +kiblnd_check_reconnect(kib_conn_t *conn, int version, + __u64 incarnation, int why, kib_connparams_t *cp) { + rwlock_t *glock = &kiblnd_data.kib_global_lock; kib_peer_t *peer = conn->ibc_peer; char *reason; - int retry = 0; + int msg_size = IBLND_MSG_SIZE; + int frag_num = -1; + int queue_dep = -1; + bool reconnect; unsigned long flags; LASSERT(conn->ibc_state == IBLND_CONN_ACTIVE_CONNECT); LASSERT(peer->ibp_connecting > 0); /* 'conn' at least */ + LASSERT(!peer->ibp_reconnecting); - write_lock_irqsave(&kiblnd_data.kib_global_lock, flags); + if (cp) { + msg_size = cp->ibcp_max_msg_size; + frag_num = cp->ibcp_max_frags; + queue_dep = cp->ibcp_queue_depth; + } - /* + write_lock_irqsave(glock, flags); + /** * retry connection if it's still needed and no other connection * attempts (active or passive) are in progress * NB: reconnect is still needed even when ibp_tx_queue is * empty if ibp_version != version because reconnect may be * initiated by kiblnd_query() */ - if ((!list_empty(&peer->ibp_tx_queue) || - peer->ibp_version != version) && - peer->ibp_connecting == 1 && - !peer->ibp_accepting) { - retry = 1; - peer->ibp_connecting++; - - peer->ibp_version = version; - peer->ibp_incarnation = incarnation; + reconnect = (!list_empty(&peer->ibp_tx_queue) || + peer->ibp_version != version) && + peer->ibp_connecting == 1 && + !peer->ibp_accepting; + if (!reconnect) { + reason = "no need"; + goto out; } - write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags); - - if (!retry) - return; - switch (why) { default: reason = "Unknown"; break; case IBLND_REJECT_RDMA_FRAGS: - if (!cp) - goto failed; - - if (conn->ibc_max_frags <= cp->ibcp_max_frags) { - CNETERR("Unsupported max frags, peer supports %d\n", - cp->ibcp_max_frags); - goto failed; - } else if (!*kiblnd_tunables.kib_map_on_demand) { - CNETERR("map_on_demand must be enabled to support map_on_demand peers\n"); - goto failed; + if (!cp) { + reason = "can't negotiate max frags"; + goto out; + } + if (!*kiblnd_tunables.kib_map_on_demand) { + reason = "map_on_demand must be enabled"; + goto out; + } + if (conn->ibc_max_frags <= frag_num) { + reason = "unsupported max frags"; + goto out; } - peer->ibp_max_frags = cp->ibcp_max_frags; + peer->ibp_max_frags = frag_num; reason = "rdma fragments"; break; case IBLND_REJECT_MSG_QUEUE_SIZE: - if (!cp) - goto failed; - - if (conn->ibc_queue_depth <= cp->ibcp_queue_depth) { - CNETERR("Unsupported queue depth, peer supports %d\n", - cp->ibcp_queue_depth); - goto failed; + if (!cp) { + reason = "can't negotiate queue depth"; + goto out; + } + if (conn->ibc_queue_depth <= queue_dep) { + reason = "unsupported queue depth"; + goto out; } - peer->ibp_queue_depth = cp->ibcp_queue_depth; + peer->ibp_queue_depth = queue_dep; reason = "queue depth"; break; @@ -2563,20 +2625,24 @@ kiblnd_reconnect(kib_conn_t *conn, int version, break; } - CNETERR("%s: retrying (%s), %x, %x, queue_dep: %d, max_frag: %d, msg_size: %d\n", - libcfs_nid2str(peer->ibp_nid), - reason, IBLND_MSG_VERSION, version, - conn->ibc_queue_depth, conn->ibc_max_frags, - cp ? cp->ibcp_max_msg_size : IBLND_MSG_SIZE); - - kiblnd_connect_peer(peer); - return; -failed: - write_lock_irqsave(&kiblnd_data.kib_global_lock, flags); - peer->ibp_connecting--; - write_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags); + conn->ibc_reconnect = 1; + peer->ibp_reconnecting = 1; + peer->ibp_version = version; + if (incarnation) + peer->ibp_incarnation = incarnation; +out: + write_unlock_irqrestore(glock, flags); - return; + CNETERR("%s: %s (%s), %x, %x, msg_size: %d, queue_depth: %d/%d, max_frags: %d/%d\n", + libcfs_nid2str(peer->ibp_nid), + reconnect ? "reconnect" : "don't reconnect", + reason, IBLND_MSG_VERSION, version, msg_size, + conn->ibc_queue_depth, queue_dep, + conn->ibc_max_frags, frag_num); + /** + * if conn::ibc_reconnect is TRUE, connd will reconnect to the peer + * while destroying the zombie + */ } static void @@ -2589,8 +2655,8 @@ kiblnd_rejected(kib_conn_t *conn, int reason, void *priv, int priv_nob) switch (reason) { case IB_CM_REJ_STALE_CONN: - kiblnd_reconnect(conn, IBLND_MSG_VERSION, 0, - IBLND_REJECT_CONN_STALE, NULL); + kiblnd_check_reconnect(conn, IBLND_MSG_VERSION, 0, + IBLND_REJECT_CONN_STALE, NULL); break; case IB_CM_REJ_INVALID_SERVICE_ID: @@ -2674,8 +2740,9 @@ kiblnd_rejected(kib_conn_t *conn, int reason, void *priv, int priv_nob) case IBLND_REJECT_CONN_UNCOMPAT: case IBLND_REJECT_MSG_QUEUE_SIZE: case IBLND_REJECT_RDMA_FRAGS: - kiblnd_reconnect(conn, rej->ibr_version, - incarnation, rej->ibr_why, cp); + kiblnd_check_reconnect(conn, rej->ibr_version, + incarnation, + rej->ibr_why, cp); break; case IBLND_REJECT_NO_RESOURCES: @@ -3179,9 +3246,21 @@ kiblnd_disconnect_conn(kib_conn_t *conn) kiblnd_peer_notify(conn->ibc_peer); } +/** + * High-water for reconnection to the same peer, reconnection attempt should + * be delayed after trying more than KIB_RECONN_HIGH_RACE. + */ +#define KIB_RECONN_HIGH_RACE 10 +/** + * Allow connd to take a break and handle other things after consecutive + * reconnection attemps. + */ +#define KIB_RECONN_BREAK 100 + int kiblnd_connd(void *arg) { + spinlock_t *lock= &kiblnd_data.kib_connd_lock; wait_queue_t wait; unsigned long flags; kib_conn_t *conn; @@ -3196,23 +3275,40 @@ kiblnd_connd(void *arg) init_waitqueue_entry(&wait, current); kiblnd_data.kib_connd = current; - spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags); + spin_lock_irqsave(lock, flags); while (!kiblnd_data.kib_shutdown) { + int reconn = 0; + dropped_lock = 0; if (!list_empty(&kiblnd_data.kib_connd_zombies)) { + kib_peer_t *peer = NULL; + conn = list_entry(kiblnd_data.kib_connd_zombies.next, kib_conn_t, ibc_list); list_del(&conn->ibc_list); + if (conn->ibc_reconnect) { + peer = conn->ibc_peer; + kiblnd_peer_addref(peer); + } - spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, - flags); + spin_unlock_irqrestore(lock, flags); dropped_lock = 1; - kiblnd_destroy_conn(conn); + kiblnd_destroy_conn(conn, !peer); - spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags); + spin_lock_irqsave(lock, flags); + if (!peer) + continue; + + conn->ibc_peer = peer; + if (peer->ibp_reconnected < KIB_RECONN_HIGH_RACE) + list_add_tail(&conn->ibc_list, + &kiblnd_data.kib_reconn_list); + else + list_add_tail(&conn->ibc_list, + &kiblnd_data.kib_reconn_wait); } if (!list_empty(&kiblnd_data.kib_connd_conns)) { @@ -3220,14 +3316,38 @@ kiblnd_connd(void *arg) kib_conn_t, ibc_list); list_del(&conn->ibc_list); - spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, - flags); + spin_unlock_irqrestore(lock, flags); dropped_lock = 1; kiblnd_disconnect_conn(conn); kiblnd_conn_decref(conn); - spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags); + spin_lock_irqsave(lock, flags); + } + + while (reconn < KIB_RECONN_BREAK) { + if (kiblnd_data.kib_reconn_sec != + ktime_get_real_seconds()) { + kiblnd_data.kib_reconn_sec = ktime_get_real_seconds(); + list_splice_init(&kiblnd_data.kib_reconn_wait, + &kiblnd_data.kib_reconn_list); + } + + if (list_empty(&kiblnd_data.kib_reconn_list)) + break; + + conn = list_entry(kiblnd_data.kib_reconn_list.next, + kib_conn_t, ibc_list); + list_del(&conn->ibc_list); + + spin_unlock_irqrestore(lock, flags); + dropped_lock = 1; + + reconn += kiblnd_reconnect_peer(conn->ibc_peer); + kiblnd_peer_decref(conn->ibc_peer); + LIBCFS_FREE(conn, sizeof(*conn)); + + spin_lock_irqsave(lock, flags); } /* careful with the jiffy wrap... */ @@ -3237,7 +3357,7 @@ kiblnd_connd(void *arg) const int p = 1; int chunk = kiblnd_data.kib_peer_hash_size; - spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, flags); + spin_unlock_irqrestore(lock, flags); dropped_lock = 1; /* @@ -3262,7 +3382,7 @@ kiblnd_connd(void *arg) } deadline += msecs_to_jiffies(p * MSEC_PER_SEC); - spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags); + spin_lock_irqsave(lock, flags); } if (dropped_lock) @@ -3271,15 +3391,15 @@ kiblnd_connd(void *arg) /* Nothing to do for 'timeout' */ set_current_state(TASK_INTERRUPTIBLE); add_wait_queue(&kiblnd_data.kib_connd_waitq, &wait); - spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, flags); + spin_unlock_irqrestore(lock, flags); schedule_timeout(timeout); remove_wait_queue(&kiblnd_data.kib_connd_waitq, &wait); - spin_lock_irqsave(&kiblnd_data.kib_connd_lock, flags); + spin_lock_irqsave(lock, flags); } - spin_unlock_irqrestore(&kiblnd_data.kib_connd_lock, flags); + spin_unlock_irqrestore(lock, flags); kiblnd_thread_fini(); return 0; -- 2.20.1