X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvcl%2Fvcl_locked.c;h=69dd15b0ef420cd89485824113cffaf6e7849ee4;hb=HEAD;hp=f3136f9d2ae767b62a227d9b3142fe37dfbd5831;hpb=f0ca1e8d92114582ec9142bd15a40f1eb0102793;p=vpp.git diff --git a/src/vcl/vcl_locked.c b/src/vcl/vcl_locked.c index f3136f9d2ae..69dd15b0ef4 100644 --- a/src/vcl/vcl_locked.c +++ b/src/vcl/vcl_locked.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2019 Cisco and/or its affiliates. + * Copyright (c) 2021 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this * You may obtain a copy of the License at: @@ -13,44 +13,115 @@ * limitations under the License. */ +/** + * VCL Locked Sessions (VLS) is a wrapper that synchronizes access to VCL APIs + * which are, by construction, not thread safe. To this end, VLS uses + * configuration and heuristics to detect how applications use sessions in + * an attempt to optimize the locking strategy. The modes of operation + * currently supported are the following: + * + * 1) per-process workers + * + * +----------+ +----------+ + * | | | | + * | process0 | | process1 | + * | | | | + * +-----+----+ +-----+----+ + * | | + * | | + * +-----+----+ +-----+----+ + * | | | | + * | vls_wrk0 | | vls_wrk1 | + * | | | | + * +-----+----+ +-----+----+ + * | | + * | | + * +-----+----+ +-----+----+ + * | | | | + * | vcl_wrk0 | | vcl_wrk1 | + * | | | | + * +----------+ +----------+ + * + * 2) per-thread workers 3) single-worker multi-thread + * + * +---------+ +---------+ +---------+ +---------+ + * | | | | | | | | + * | thread0 | | thread1 | | thread0 | | thread1 | + * | | | | | | | | + * +--------++ +-+-------+ +--------++ +-+-------+ + * | | | | + * | | | | + * +-+------+-+ +-+------+-+ + * | | | | + * | vls_wrk0 | | vls_wrk0 | + * | | | | + * +-+------+-+ +----+-----+ + * | | | + * | | | + * +--------+-+ +-+--------+ +----+-----+ + * | | | | | | + * | vcl_wrk0 | | vcl_wrk1 | | vcl_wrk0 | + * | | | | | | + * +----------+ +----------+ +----------+ + * + * 1) per-process workers: intercept fork calls and assume all children + * processes are new workers that must be registered with vcl. VLS + * sessions are cloned and shared between workers. Only shared sessions + * are locked on use and thereby only one process can interact with + * them at a time (explicit sharing). + * + * 2) per-thread workers: each newly detected pthread is assumed to be a new + * worker and is registered with vcl. Enabled via configuration. + * When a thread tries to access a session it does not own, a clone and + * share rpc request is sent to the owning thread via vcl and vpp. + * Consequently, a vls session can map to multiple vcl sessions, one per + * vcl worker. VLS sessions are locked on use (implicit sharing). + * + * 3) single-worker multi-thread: vls does not make any assumptions about + * application threads and therefore implements an aggressive locking + * strategy that limits access to underlying vcl resources based on type + * of interaction and locks vls session on use (implicit sharing). + */ + #include #include typedef struct vls_shared_data_ { - clib_spinlock_t lock; - u32 owner_wrk_index; - u32 *workers_subscribed; - clib_bitmap_t *listeners; + clib_spinlock_t lock; /**< shared data lock */ + u32 owner_wrk_index; /**< vcl wrk that owns session */ + u32 *workers_subscribed; /**< vec of wrks subscribed to session */ + clib_bitmap_t *listeners; /**< bitmap of wrks actively listening */ } vls_shared_data_t; typedef struct vcl_locked_session_ { - clib_spinlock_t lock; - u32 session_index; - u32 worker_index; - u32 vls_index; - u32 shared_data_index; - /** VCL session owned by different workers because of migration */ - u32 owner_vcl_wrk_index; - uword *vcl_wrk_index_to_session_index; + clib_spinlock_t lock; /**< vls lock when in use */ + u32 session_index; /**< vcl session index */ + u32 vcl_wrk_index; /**< vcl worker index */ + u32 vls_index; /**< index in vls pool */ + u32 shared_data_index; /**< shared data index if any */ + u32 owner_vcl_wrk_index; /**< vcl wrk of the vls wrk at alloc */ + uword *vcl_wrk_index_to_session_index; /**< map vcl wrk to session */ } vcl_locked_session_t; typedef struct vls_worker_ { - vcl_locked_session_t *vls_pool; - uword *session_handle_to_vlsh_table; - u32 wrk_index; + clib_rwlock_t sh_to_vlsh_table_lock; /**< ht rwlock with mt workers */ + vcl_locked_session_t *vls_pool; /**< pool of vls session */ + uword *sh_to_vlsh_table; /**< map from vcl sh to vls sh */ + u32 *pending_vcl_wrk_cleanup; /**< child vcl wrks to cleanup */ + u32 vcl_wrk_index; /**< if 1:1 map vls to vcl wrk */ } vls_worker_t; typedef struct vls_local_ { - int vls_wrk_index; - volatile int vls_mt_n_threads; - pthread_mutex_t vls_mt_mq_mlock; - pthread_mutex_t vls_mt_spool_mlock; - volatile u8 select_mp_check; - volatile u8 epoll_mp_check; + int vls_wrk_index; /**< vls wrk index, 1 per process */ + volatile int vls_mt_n_threads; /**< number of threads detected */ + clib_rwlock_t vls_pool_lock; /**< per process/wrk vls pool locks */ + pthread_mutex_t vls_mt_mq_mlock; /**< vcl mq lock */ + pthread_mutex_t vls_mt_spool_mlock; /**< vcl select or pool lock */ + volatile u8 select_mp_check; /**< flag set if select checks done */ } vls_process_local_t; static vls_process_local_t vls_local; @@ -58,15 +129,21 @@ static vls_process_local_t *vlsl = &vls_local; typedef struct vls_main_ { - vls_worker_t *workers; - clib_rwlock_t vls_table_lock; - /** Pool of data shared by sessions owned by different workers */ - vls_shared_data_t *shared_data_pool; - clib_rwlock_t shared_data_lock; + vls_worker_t *workers; /**< pool of vls workers */ + vls_shared_data_t *shared_data_pool; /**< inter proc pool of shared data */ + clib_rwlock_t shared_data_lock; /**< shared data pool lock */ + clib_spinlock_t worker_rpc_lock; /**< lock for inter-worker rpcs */ } vls_main_t; vls_main_t *vlsm; +typedef enum +{ + VLS_RPC_STATE_INIT, + VLS_RPC_STATE_SUCCESS, + VLS_RPC_STATE_SESSION_NOT_EXIST, +} vls_rpc_state_e; + typedef enum vls_rpc_msg_type_ { VLS_RPC_CLONE_AND_SHARE, @@ -97,20 +174,18 @@ typedef struct vls_sess_cleanup_msg_ void vls_send_session_cleanup_rpc (vcl_worker_t * wrk, u32 dst_wrk_index, u32 dst_session_index); -void vls_send_clone_and_share_rpc (vcl_worker_t * wrk, - vcl_locked_session_t * vls, +void vls_send_clone_and_share_rpc (vcl_worker_t *wrk, u32 origin_vls_index, u32 session_index, u32 vls_wrk_index, u32 dst_wrk_index, u32 dst_vls_index, u32 dst_session_index); - +static void vls_cleanup_forked_child (vcl_worker_t *wrk, + vcl_worker_t *child_wrk); +static void vls_handle_pending_wrk_cleanup (void); static inline u32 vls_get_worker_index (void) { - if (vls_mt_wrk_supported ()) - return vlsl->vls_wrk_index; - else - return vcl_get_worker_index (); + return vlsl->vls_wrk_index; } static u32 @@ -169,31 +244,31 @@ vls_shared_data_pool_runlock (void) } static inline void -vls_mt_table_rlock (void) +vls_mt_pool_rlock (void) { if (vlsl->vls_mt_n_threads > 1) - clib_rwlock_reader_lock (&vlsm->vls_table_lock); + clib_rwlock_reader_lock (&vlsl->vls_pool_lock); } static inline void -vls_mt_table_runlock (void) +vls_mt_pool_runlock (void) { if (vlsl->vls_mt_n_threads > 1) - clib_rwlock_reader_unlock (&vlsm->vls_table_lock); + clib_rwlock_reader_unlock (&vlsl->vls_pool_lock); } static inline void -vls_mt_table_wlock (void) +vls_mt_pool_wlock (void) { if (vlsl->vls_mt_n_threads > 1) - clib_rwlock_writer_lock (&vlsm->vls_table_lock); + clib_rwlock_writer_lock (&vlsl->vls_pool_lock); } static inline void -vls_mt_table_wunlock (void) +vls_mt_pool_wunlock (void) { if (vlsl->vls_mt_n_threads > 1) - clib_rwlock_writer_unlock (&vlsm->vls_table_lock); + clib_rwlock_writer_unlock (&vlsl->vls_pool_lock); } typedef enum @@ -289,7 +364,7 @@ vls_to_sh_tu (vcl_locked_session_t * vls) { vcl_session_handle_t sh; sh = vls_to_sh (vls); - vls_mt_table_runlock (); + vls_mt_pool_runlock (); return sh; } @@ -305,13 +380,19 @@ vls_worker_alloc (void) vls_worker_t *wrk; pool_get_zero (vlsm->workers, wrk); - wrk->wrk_index = vcl_get_worker_index (); + if (vls_mt_wrk_supported ()) + clib_rwlock_init (&wrk->sh_to_vlsh_table_lock); + wrk->vcl_wrk_index = vcl_get_worker_index (); + vec_validate (wrk->pending_vcl_wrk_cleanup, 16); + vec_reset_length (wrk->pending_vcl_wrk_cleanup); } static void vls_worker_free (vls_worker_t * wrk) { - hash_free (wrk->session_handle_to_vlsh_table); + hash_free (wrk->sh_to_vlsh_table); + if (vls_mt_wrk_supported ()) + clib_rwlock_free (&wrk->sh_to_vlsh_table_lock); pool_free (wrk->vls_pool); pool_put (vlsm->workers, wrk); } @@ -324,29 +405,60 @@ vls_worker_get (u32 wrk_index) return pool_elt_at_index (vlsm->workers, wrk_index); } +static void +vls_sh_to_vlsh_table_add (vls_worker_t *wrk, vcl_session_handle_t sh, u32 vlsh) +{ + if (vls_mt_wrk_supported ()) + clib_rwlock_writer_lock (&wrk->sh_to_vlsh_table_lock); + hash_set (wrk->sh_to_vlsh_table, sh, vlsh); + if (vls_mt_wrk_supported ()) + clib_rwlock_writer_unlock (&wrk->sh_to_vlsh_table_lock); +} + +static void +vls_sh_to_vlsh_table_del (vls_worker_t *wrk, vcl_session_handle_t sh) +{ + if (vls_mt_wrk_supported ()) + clib_rwlock_writer_lock (&wrk->sh_to_vlsh_table_lock); + hash_unset (wrk->sh_to_vlsh_table, sh); + if (vls_mt_wrk_supported ()) + clib_rwlock_writer_unlock (&wrk->sh_to_vlsh_table_lock); +} + +static uword * +vls_sh_to_vlsh_table_get (vls_worker_t *wrk, vcl_session_handle_t sh) +{ + if (vls_mt_wrk_supported ()) + clib_rwlock_reader_lock (&wrk->sh_to_vlsh_table_lock); + uword *vlshp = hash_get (wrk->sh_to_vlsh_table, sh); + if (vls_mt_wrk_supported ()) + clib_rwlock_reader_unlock (&wrk->sh_to_vlsh_table_lock); + return vlshp; +} + static vls_handle_t vls_alloc (vcl_session_handle_t sh) { vls_worker_t *wrk = vls_worker_get_current (); vcl_locked_session_t *vls; - vls_mt_table_wlock (); + vls_mt_pool_wlock (); pool_get_zero (wrk->vls_pool, vls); vls->session_index = vppcom_session_index (sh); - vls->worker_index = vppcom_session_worker (sh); + vls->vcl_wrk_index = vppcom_session_worker (sh); vls->vls_index = vls - wrk->vls_pool; vls->shared_data_index = ~0; - hash_set (wrk->session_handle_to_vlsh_table, sh, vls->vls_index); + vls_sh_to_vlsh_table_add (wrk, sh, vls->vls_index); if (vls_mt_wrk_supported ()) { - hash_set (vls->vcl_wrk_index_to_session_index, vls->worker_index, + hash_set (vls->vcl_wrk_index_to_session_index, vls->vcl_wrk_index, vls->session_index); - vls->owner_vcl_wrk_index = vls->worker_index; + vls->owner_vcl_wrk_index = vls->vcl_wrk_index; } clib_spinlock_init (&vls->lock); - vls_mt_table_wunlock (); + vls_mt_pool_wunlock (); return vls->vls_index; } @@ -365,8 +477,8 @@ vls_free (vcl_locked_session_t * vls) vls_worker_t *wrk = vls_worker_get_current (); ASSERT (vls != 0); - hash_unset (wrk->session_handle_to_vlsh_table, - vcl_session_handle_from_index (vls->session_index)); + vls_sh_to_vlsh_table_del ( + wrk, vcl_session_handle_from_index (vls->session_index)); clib_spinlock_free (&vls->lock); pool_put (wrk->vls_pool, vls); } @@ -387,10 +499,10 @@ static vcl_locked_session_t * vls_get_w_dlock (vls_handle_t vlsh) { vcl_locked_session_t *vls; - vls_mt_table_rlock (); + vls_mt_pool_rlock (); vls = vls_get_and_lock (vlsh); if (!vls) - vls_mt_table_runlock (); + vls_mt_pool_runlock (); return vls; } @@ -398,17 +510,17 @@ static inline void vls_get_and_unlock (vls_handle_t vlsh) { vcl_locked_session_t *vls; - vls_mt_table_rlock (); + vls_mt_pool_rlock (); vls = vls_get (vlsh); vls_unlock (vls); - vls_mt_table_runlock (); + vls_mt_pool_runlock (); } static inline void vls_dunlock (vcl_locked_session_t * vls) { vls_unlock (vls); - vls_mt_table_runlock (); + vls_mt_pool_runlock (); } static vcl_locked_session_t * @@ -445,10 +557,10 @@ vls_handle_t vls_si_wi_to_vlsh (u32 session_index, u32 vcl_wrk_index) { vls_worker_t *wrk = vls_worker_get_current (); - uword *vlshp; - vlshp = hash_get (wrk->session_handle_to_vlsh_table, - vcl_session_handle_from_wrk_session_index (session_index, - vcl_wrk_index)); + uword *vlshp = vls_sh_to_vlsh_table_get ( + wrk, + vcl_session_handle_from_wrk_session_index (session_index, vcl_wrk_index)); + return vlshp ? *vlshp : VLS_INVALID_HANDLE; } @@ -457,9 +569,9 @@ vls_session_index_to_vlsh (uint32_t session_index) { vls_handle_t vlsh; - vls_mt_table_rlock (); + vls_mt_pool_rlock (); vlsh = vls_si_wi_to_vlsh (session_index, vcl_get_worker_index ()); - vls_mt_table_runlock (); + vls_mt_pool_runlock (); return vlsh; } @@ -507,7 +619,8 @@ vls_listener_wrk_set (vcl_locked_session_t * vls, u32 wrk_index, u8 is_active) vls_shd = vls_shared_data_get (vls->shared_data_index); clib_spinlock_lock (&vls_shd->lock); - clib_bitmap_set (vls_shd->listeners, wrk_index, is_active); + vls_shd->listeners = + clib_bitmap_set (vls_shd->listeners, wrk_index, is_active); clib_spinlock_unlock (&vls_shd->lock); vls_shared_data_pool_runlock (); @@ -557,8 +670,19 @@ vls_listener_wrk_is_active (vcl_locked_session_t * vls, u32 wrk_index) static void vls_listener_wrk_start_listen (vcl_locked_session_t * vls, u32 wrk_index) { - vppcom_session_listen (vls_to_sh (vls), ~0); - vls_listener_wrk_set (vls, wrk_index, 1 /* is_active */ ); + vcl_worker_t *wrk; + vcl_session_t *ls; + + wrk = vcl_worker_get (wrk_index); + ls = vcl_session_get (wrk, vls->session_index); + + /* Listen request already sent */ + if (ls->flags & VCL_SESSION_F_PENDING_LISTEN) + return; + + vcl_send_session_listen (wrk, ls); + + vls_listener_wrk_set (vls, wrk_index, 1 /* is_active */); } static void @@ -614,7 +738,7 @@ vls_unshare_session (vcl_locked_session_t * vls, vcl_worker_t * wrk) if (pos < 0) { clib_warning ("worker %u not subscribed for vls %u", wrk->wrk_index, - vls->worker_index); + vls->vcl_wrk_index); goto done; } @@ -661,7 +785,8 @@ vls_unshare_session (vcl_locked_session_t * vls, vcl_worker_t * wrk) * Check if we can change owner or close */ vls_shd->owner_wrk_index = vls_shd->workers_subscribed[0]; - vcl_send_session_worker_update (wrk, s, vls_shd->owner_wrk_index); + if (s->vpp_evt_q) + vcl_send_session_worker_update (wrk, s, vls_shd->owner_wrk_index); /* XXX is this still needed? */ if (vec_len (vls_shd->workers_subscribed) > 1) @@ -685,9 +810,9 @@ vls_init_share_session (vls_worker_t * vls_wrk, vcl_locked_session_t * vls) vls_shared_data_pool_rlock (); vls_shd = vls_shared_data_get (vls_shd_index); - vls_shd->owner_wrk_index = vls_wrk->wrk_index; + vls_shd->owner_wrk_index = vls_wrk->vcl_wrk_index; vls->shared_data_index = vls_shd_index; - vec_add1 (vls_shd->workers_subscribed, vls_wrk->wrk_index); + vec_add1 (vls_shd->workers_subscribed, vls_wrk->vcl_wrk_index); vls_shared_data_pool_runlock (); } @@ -695,7 +820,7 @@ vls_init_share_session (vls_worker_t * vls_wrk, vcl_locked_session_t * vls) void vls_share_session (vls_worker_t * vls_wrk, vcl_locked_session_t * vls) { - vcl_worker_t *vcl_wrk = vcl_worker_get (vls_wrk->wrk_index); + vcl_worker_t *vcl_wrk = vcl_worker_get (vls_wrk->vcl_wrk_index); vls_shared_data_t *vls_shd; vcl_session_t *s; @@ -717,19 +842,19 @@ vls_share_session (vls_worker_t * vls_wrk, vcl_locked_session_t * vls) vls_shd = vls_shared_data_get (vls->shared_data_index); clib_spinlock_lock (&vls_shd->lock); - vec_add1 (vls_shd->workers_subscribed, vls_wrk->wrk_index); + vec_add1 (vls_shd->workers_subscribed, vls_wrk->vcl_wrk_index); clib_spinlock_unlock (&vls_shd->lock); vls_shared_data_pool_runlock (); - if (s->rx_fifo) + if (s->session_state == VCL_STATE_LISTEN) { - svm_fifo_add_subscriber (s->rx_fifo, vcl_wrk->vpp_wrk_index); - svm_fifo_add_subscriber (s->tx_fifo, vcl_wrk->vpp_wrk_index); + s->session_state = VCL_STATE_LISTEN_NO_MQ; + s->rx_fifo = s->tx_fifo = 0; } - else if (s->session_state == VCL_STATE_LISTEN) + else if (s->rx_fifo) { - s->session_state = VCL_STATE_LISTEN_NO_MQ; + vcl_session_share_fifos (s, s->rx_fifo, s->tx_fifo); } } @@ -738,7 +863,6 @@ vls_share_sessions (vls_worker_t * vls_parent_wrk, vls_worker_t * vls_wrk) { vcl_locked_session_t *vls, *parent_vls; - /* *INDENT-OFF* */ pool_foreach (vls, vls_wrk->vls_pool) { /* Initialize sharing on parent session */ if (vls->shared_data_index == ~0) @@ -749,38 +873,77 @@ vls_share_sessions (vls_worker_t * vls_parent_wrk, vls_worker_t * vls_wrk) } vls_share_session (vls_wrk, vls); } - /* *INDENT-ON* */ +} + +static void +vls_validate_veps (vcl_worker_t *wrk) +{ + vcl_session_t *s; + u32 session_index, wrk_index; + + pool_foreach (s, wrk->sessions) + { + if (s->vep.vep_sh != ~0) + { + vcl_session_handle_parse (s->vep.vep_sh, &wrk_index, &session_index); + s->vep.vep_sh = vcl_session_handle_from_index (session_index); + } + if (s->vep.next_sh != ~0) + { + vcl_session_handle_parse (s->vep.next_sh, &wrk_index, + &session_index); + s->vep.next_sh = vcl_session_handle_from_index (session_index); + } + if (s->vep.prev_sh != ~0) + { + vcl_session_handle_parse (s->vep.prev_sh, &wrk_index, + &session_index); + s->vep.prev_sh = vcl_session_handle_from_index (session_index); + } + } } void vls_worker_copy_on_fork (vcl_worker_t * parent_wrk) { vls_worker_t *vls_wrk = vls_worker_get_current (), *vls_parent_wrk; - vcl_worker_t *wrk = vcl_worker_get_current (); + vcl_worker_t *vcl_wrk = vcl_worker_get_current (); u32 vls_index, session_index, wrk_index; vcl_session_handle_t sh; + vcl_locked_session_t *vls; /* * init vcl worker */ - wrk->sessions = pool_dup (parent_wrk->sessions); - wrk->session_index_by_vpp_handles = + vcl_wrk->sessions = pool_dup (parent_wrk->sessions); + vcl_wrk->session_index_by_vpp_handles = hash_dup (parent_wrk->session_index_by_vpp_handles); /* * init vls worker */ vls_parent_wrk = vls_worker_get (parent_wrk->wrk_index); - /* *INDENT-OFF* */ - hash_foreach (sh, vls_index, vls_parent_wrk->session_handle_to_vlsh_table, - ({ - vcl_session_handle_parse (sh, &wrk_index, &session_index); - hash_set (vls_wrk->session_handle_to_vlsh_table, - vcl_session_handle_from_index (session_index), vls_index); - })); - /* *INDENT-ON* */ + + /* clang-format off */ + hash_foreach (sh, vls_index, vls_parent_wrk->sh_to_vlsh_table, ({ + vcl_session_handle_parse (sh, &wrk_index, &session_index); + hash_set (vls_wrk->sh_to_vlsh_table, + vcl_session_handle_from_index (session_index), vls_index); + })); + /* clang-format on */ vls_wrk->vls_pool = pool_dup (vls_parent_wrk->vls_pool); + /* + * Detach vls from parent vcl worker and attach them to child. + */ + pool_foreach (vls, vls_wrk->vls_pool) + { + vls->vcl_wrk_index = vcl_wrk->wrk_index; + } + + /* Validate vep's handle */ + vls_validate_veps (vcl_wrk); + vls_share_sessions (vls_parent_wrk, vls_wrk); } @@ -845,20 +1008,21 @@ vls_mt_rel_locks (int locks_acq) static inline u8 vls_mt_session_should_migrate (vcl_locked_session_t * vls) { - return (vls_mt_wrk_supported () - && vls->worker_index != vcl_get_worker_index ()); + return (vls_mt_wrk_supported () && + vls->vcl_wrk_index != vcl_get_worker_index ()); } -static void -vls_mt_session_migrate (vcl_locked_session_t * vls) +static vcl_locked_session_t * +vls_mt_session_migrate (vcl_locked_session_t *vls) { u32 wrk_index = vcl_get_worker_index (); vcl_worker_t *wrk; - u32 src_sid, sid; + vls_worker_t *vls_wrk = vls_worker_get_current (); + u32 src_sid, sid, vls_index, own_vcl_wrk_index; vcl_session_t *session; uword *p; - ASSERT (vls_mt_wrk_supported () && vls->worker_index != wrk_index); + ASSERT (vls_mt_wrk_supported () && vls->vcl_wrk_index != wrk_index); /* * VCL session on current vcl worker already allocated. Update current @@ -866,9 +1030,9 @@ vls_mt_session_migrate (vcl_locked_session_t * vls) */ if ((p = hash_get (vls->vcl_wrk_index_to_session_index, wrk_index))) { - vls->worker_index = wrk_index; + vls->vcl_wrk_index = wrk_index; vls->session_index = (u32) p[0]; - return; + return vls; } /* @@ -881,40 +1045,70 @@ vls_mt_session_migrate (vcl_locked_session_t * vls) { VERR ("session in owner worker(%u) is free", vls->owner_vcl_wrk_index); ASSERT (0); - return; + vls_unlock (vls); + vls_mt_pool_runlock (); + return 0; } src_sid = (u32) p[0]; wrk = vcl_worker_get_current (); session = vcl_session_alloc (wrk); sid = session->session_index; - vls_send_clone_and_share_rpc (wrk, vls, sid, vls_get_worker_index (), - vls->owner_vcl_wrk_index, vls->vls_index, - src_sid); - session->session_index = sid; - vls->worker_index = wrk_index; - vls->session_index = sid; - hash_set (vls->vcl_wrk_index_to_session_index, wrk_index, sid); VDBG (1, "migrate session of worker (session): %u (%u) -> %u (%u)", vls->owner_vcl_wrk_index, src_sid, wrk_index, sid); - if (PREDICT_FALSE ((session->flags & VCL_SESSION_F_IS_VEP) - && session->vep.next_sh != ~0)) + /* Drop lock to prevent dead lock when dst wrk trying to get lock. */ + vls_index = vls->vls_index; + own_vcl_wrk_index = vls->owner_vcl_wrk_index; + vls_unlock (vls); + vls_mt_pool_runlock (); + vls_send_clone_and_share_rpc (wrk, vls_index, sid, vls_get_worker_index (), + own_vcl_wrk_index, vls_index, src_sid); + + if (PREDICT_FALSE (wrk->rpc_done == VLS_RPC_STATE_SESSION_NOT_EXIST)) + { + VWRN ("session %u not exist", src_sid); + goto err; + } + else if (PREDICT_FALSE (wrk->rpc_done == VLS_RPC_STATE_INIT)) + { + VWRN ("failed to wait rpc response"); + goto err; + } + else if (PREDICT_FALSE ((session->flags & VCL_SESSION_F_IS_VEP) && + session->vep.next_sh != ~0)) { - /* TODO: rollback? */ VERR ("can't migrate nonempty epoll session"); ASSERT (0); - return; + goto err; } else if (PREDICT_FALSE (!(session->flags & VCL_SESSION_F_IS_VEP) && session->session_state != VCL_STATE_CLOSED)) { - /* TODO: rollback? */ VERR ("migrate NOT supported, session_status (%u)", session->session_state); ASSERT (0); - return; + goto err; } + + vls = vls_get_w_dlock (vls_index); + if (PREDICT_FALSE (!vls)) + { + VWRN ("failed to get vls %u", vls_index); + goto err; + } + + session->session_index = sid; + vls->vcl_wrk_index = wrk_index; + vls->session_index = sid; + hash_set (vls->vcl_wrk_index_to_session_index, wrk_index, sid); + vls_sh_to_vlsh_table_add (vls_wrk, vcl_session_handle (session), + vls->vls_index); + return vls; + +err: + vcl_session_free (wrk, session); + return 0; } static inline void @@ -924,20 +1118,24 @@ vls_mt_detect (void) vls_mt_add (); } -#define vls_mt_guard(_vls, _op) \ - int _locks_acq = 0; \ - if (vls_mt_wrk_supported ()) \ - { \ - if (PREDICT_FALSE (_vls \ - && ((vcl_locked_session_t *)_vls)->worker_index != \ - vcl_get_worker_index ())) \ - vls_mt_session_migrate (_vls); \ - } \ - else \ - { \ - if (PREDICT_FALSE (vlsl->vls_mt_n_threads > 1)) \ - vls_mt_acq_locks (_vls, _op, &_locks_acq); \ - } \ +#define vls_mt_guard(_vls, _op) \ + int _locks_acq = 0; \ + if (vls_mt_wrk_supported ()) \ + { \ + if (PREDICT_FALSE (_vls && \ + ((vcl_locked_session_t *) _vls)->vcl_wrk_index != \ + vcl_get_worker_index ())) \ + { \ + _vls = vls_mt_session_migrate (_vls); \ + if (PREDICT_FALSE (!_vls)) \ + return VPPCOM_EBADFD; \ + } \ + } \ + else \ + { \ + if (PREDICT_FALSE (vlsl->vls_mt_n_threads > 1)) \ + vls_mt_acq_locks (_vls, _op, &_locks_acq); \ + } #define vls_mt_unguard() \ if (PREDICT_FALSE (_locks_acq)) \ @@ -1037,7 +1235,11 @@ vls_attr (vls_handle_t vlsh, uint32_t op, void *buffer, uint32_t * buflen) if (!(vls = vls_get_w_dlock (vlsh))) return VPPCOM_EBADFD; if (vls_mt_session_should_migrate (vls)) - vls_mt_session_migrate (vls); + { + vls = vls_mt_session_migrate (vls); + if (PREDICT_FALSE (!vls)) + return VPPCOM_EBADFD; + } rv = vppcom_session_attr (vls_to_sh_tu (vls), op, buffer, buflen); vls_get_and_unlock (vlsh); return rv; @@ -1099,23 +1301,30 @@ vls_mp_checks (vcl_locked_session_t * vls, int is_add) if (vls_mt_wrk_supported ()) return; + ASSERT (wrk->wrk_index == vls->vcl_wrk_index); s = vcl_session_get (wrk, vls->session_index); switch (s->session_state) { case VCL_STATE_LISTEN: if (is_add) { - vls_listener_wrk_set (vls, vls->worker_index, 1 /* is_active */ ); + vls_listener_wrk_set (vls, vls->vcl_wrk_index, 1 /* is_active */); break; } - vls_listener_wrk_stop_listen (vls, vls->worker_index); + /* Although removal from epoll means listener no longer accepts new + * sessions, the accept queue built by vpp cannot be drained by stopping + * the listener. Morover, some applications, e.g., nginx, might + * constantly remove and add listeners to their epfds. Removing + * listeners in such situations causes a lot of churn in vpp as segments + * and segment managers need to be recreated. */ + /* vls_listener_wrk_stop_listen (vls, vls->vcl_wrk_index); */ break; case VCL_STATE_LISTEN_NO_MQ: if (!is_add) break; /* Register worker as listener */ - vls_listener_wrk_start_listen (vls, wrk->wrk_index); + vls_listener_wrk_start_listen (vls, vls->vcl_wrk_index); /* If owner worker did not attempt to accept/xpoll on the session, * force a listen stop for it, since it may not be interested in @@ -1162,9 +1371,10 @@ vls_create (uint8_t proto, uint8_t is_nonblocking) { vcl_session_handle_t sh; vls_handle_t vlsh; + vcl_locked_session_t *vls = NULL; vls_mt_detect (); - vls_mt_guard (0, VLS_MT_OP_SPOOL); + vls_mt_guard (vls, VLS_MT_OP_SPOOL); sh = vppcom_session_create (proto, is_nonblocking); vls_mt_unguard (); if (sh == INVALID_SESSION_ID) @@ -1187,13 +1397,11 @@ vls_mt_session_cleanup (vcl_locked_session_t * vls) current_vcl_wrk = vcl_get_worker_index (); - /* *INDENT-OFF* */ hash_foreach (wrk_index, session_index, vls->vcl_wrk_index_to_session_index, ({ if (current_vcl_wrk != wrk_index) vls_send_session_cleanup_rpc (wrk, wrk_index, session_index); })); - /* *INDENT-ON* */ hash_free (vls->vcl_wrk_index_to_session_index); } @@ -1204,12 +1412,12 @@ vls_close (vls_handle_t vlsh) int rv; vls_mt_detect (); - vls_mt_table_wlock (); + vls_mt_pool_wlock (); vls = vls_get_and_lock (vlsh); if (!vls) { - vls_mt_table_wunlock (); + vls_mt_pool_wunlock (); return VPPCOM_EBADFD; } @@ -1226,7 +1434,25 @@ vls_close (vls_handle_t vlsh) vls_free (vls); vls_mt_unguard (); - vls_mt_table_wunlock (); + vls_mt_pool_wunlock (); + + return rv; +} + +int +vls_shutdown (vls_handle_t vlsh, int how) +{ + vcl_locked_session_t *vls; + int rv; + + vls_mt_detect (); + if (!(vls = vls_get_w_dlock (vlsh))) + return VPPCOM_EBADFD; + + vls_mt_guard (vls, VLS_MT_OP_SPOOL); + rv = vppcom_session_shutdown (vls_to_sh_tu (vls), how); + vls_mt_unguard (); + vls_get_and_unlock (vlsh); return rv; } @@ -1253,16 +1479,9 @@ vls_epoll_create (void) static void vls_epoll_ctl_mp_checks (vcl_locked_session_t * vls, int op) { - if (vcl_n_workers () <= 1) - { - vlsl->epoll_mp_check = 1; - return; - } - - if (op == EPOLL_CTL_MOD) + if (vcl_n_workers () <= 1 || op == EPOLL_CTL_MOD) return; - vlsl->epoll_mp_check = 1; vls_mp_checks (vls, op == EPOLL_CTL_ADD); } @@ -1275,29 +1494,46 @@ vls_epoll_ctl (vls_handle_t ep_vlsh, int op, vls_handle_t vlsh, int rv; vls_mt_detect (); - vls_mt_table_rlock (); + vls_mt_pool_rlock (); + ep_vls = vls_get_and_lock (ep_vlsh); - vls = vls_get_and_lock (vlsh); + if (PREDICT_FALSE (!ep_vls)) + { + vls_mt_pool_runlock (); + return VPPCOM_EBADFD; + } if (vls_mt_session_should_migrate (ep_vls)) - vls_mt_session_migrate (ep_vls); + { + ep_vls = vls_mt_session_migrate (ep_vls); + if (PREDICT_FALSE (!ep_vls)) + { + vls_mt_pool_runlock (); + return VPPCOM_EBADFD; + } + } + + vls = vls_get_and_lock (vlsh); + if (PREDICT_FALSE (!vls)) + { + vls_unlock (ep_vls); + vls_mt_pool_runlock (); + return VPPCOM_EBADFD; + } ep_sh = vls_to_sh (ep_vls); sh = vls_to_sh (vls); - if (PREDICT_FALSE (!vlsl->epoll_mp_check)) - vls_epoll_ctl_mp_checks (vls, op); - - vls_mt_table_runlock (); - + vls_epoll_ctl_mp_checks (vls, op); + vls_mt_pool_runlock (); rv = vppcom_epoll_ctl (ep_sh, op, sh, event); - vls_mt_table_rlock (); + vls_mt_pool_rlock (); ep_vls = vls_get (ep_vlsh); vls = vls_get (vlsh); vls_unlock (vls); vls_unlock (ep_vls); - vls_mt_table_runlock (); + vls_mt_pool_runlock (); return rv; } @@ -1305,17 +1541,18 @@ int vls_epoll_wait (vls_handle_t ep_vlsh, struct epoll_event *events, int maxevents, double wait_for_time) { - vcl_locked_session_t *vls; + vcl_locked_session_t *vls, *vls_tmp = NULL; int rv; vls_mt_detect (); if (!(vls = vls_get_w_dlock (ep_vlsh))) return VPPCOM_EBADFD; - vls_mt_guard (0, VLS_MT_OP_XPOLL); + vls_mt_guard (vls_tmp, VLS_MT_OP_XPOLL); rv = vppcom_epoll_wait (vls_to_sh_tu (vls), events, maxevents, wait_for_time); vls_mt_unguard (); vls_get_and_unlock (ep_vlsh); + vls_handle_pending_wrk_cleanup (); return rv; } @@ -1339,7 +1576,6 @@ vls_select_mp_checks (vcl_si_set * read_map) vlsl->select_mp_check = 1; wrk = vcl_worker_get_current (); - /* *INDENT-OFF* */ clib_bitmap_foreach (si, read_map) { s = vcl_session_get (wrk, si); if (s->session_state == VCL_STATE_LISTEN) @@ -1348,7 +1584,6 @@ vls_select_mp_checks (vcl_si_set * read_map) vls_mp_checks (vls, 1 /* is_add */); } } - /* *INDENT-ON* */ } int @@ -1356,13 +1591,15 @@ vls_select (int n_bits, vcl_si_set * read_map, vcl_si_set * write_map, vcl_si_set * except_map, double wait_for_time) { int rv; + vcl_locked_session_t *vls = NULL; vls_mt_detect (); - vls_mt_guard (0, VLS_MT_OP_XPOLL); + vls_mt_guard (vls, VLS_MT_OP_XPOLL); if (PREDICT_FALSE (!vlsl->select_mp_check)) vls_select_mp_checks (read_map); rv = vppcom_select (n_bits, read_map, write_map, except_map, wait_for_time); vls_mt_unguard (); + vls_handle_pending_wrk_cleanup (); return rv; } @@ -1379,13 +1616,11 @@ vls_unshare_vcl_worker_sessions (vcl_worker_t * wrk) current_wrk = vcl_get_worker_index (); is_current = current_wrk == wrk->wrk_index; - /* *INDENT-OFF* */ pool_foreach (s, wrk->sessions) { vls = vls_get (vls_si_wi_to_vlsh (s->session_index, wrk->wrk_index)); if (vls && (is_current || vls_is_shared_by_wrk (vls, current_wrk))) vls_unshare_session (vls, wrk); } - /* *INDENT-ON* */ } static void @@ -1396,7 +1631,11 @@ vls_cleanup_vcl_worker (vcl_worker_t * wrk) /* Unshare sessions and also cleanup worker since child may have * called _exit () and therefore vcl may not catch the event */ vls_unshare_vcl_worker_sessions (wrk); - vcl_worker_cleanup (wrk, 1 /* notify vpp */ ); + + /* Since child may have exited and thereforce fd of vpp_app_socket_api + * may have been closed, so DONOT notify VPP. + */ + vcl_worker_cleanup (wrk, vcm->cfg.vpp_app_socket_api ? 0 : 1); vls_worker_free (vls_wrk); } @@ -1424,12 +1663,34 @@ vls_cleanup_forked_child (vcl_worker_t * wrk, vcl_worker_t * child_wrk) wrk->forked_child = ~0; } +static void +vls_handle_pending_wrk_cleanup (void) +{ + u32 *wip; + vcl_worker_t *child_wrk, *wrk; + vls_worker_t *vls_wrk = vls_worker_get_current (); + + if (PREDICT_TRUE (vec_len (vls_wrk->pending_vcl_wrk_cleanup) == 0)) + return; + + wrk = vcl_worker_get_current (); + vec_foreach (wip, vls_wrk->pending_vcl_wrk_cleanup) + { + child_wrk = vcl_worker_get_if_valid (*wip); + if (!child_wrk) + continue; + vls_cleanup_forked_child (wrk, child_wrk); + } + vec_reset_length (vls_wrk->pending_vcl_wrk_cleanup); +} + static struct sigaction old_sa; static void vls_intercept_sigchld_handler (int signum, siginfo_t * si, void *uc) { vcl_worker_t *wrk, *child_wrk; + vls_worker_t *vls_wrk; if (vcl_get_worker_index () == ~0) return; @@ -1453,7 +1714,14 @@ vls_intercept_sigchld_handler (int signum, siginfo_t * si, void *uc) VDBG (0, "unexpected child pid %u", si->si_pid); goto done; } - vls_cleanup_forked_child (wrk, child_wrk); + + /* Parent process may enter sighandler with a lock, such as lock in localtime + * or in mspace_free, and child wrk cleanup may try to get such locks and + * cause deadlock. + * So move child wrk cleanup from sighandler to vls_epoll_wait/vls_select. + */ + vls_wrk = vls_worker_get_current (); + vec_add1 (vls_wrk->pending_vcl_wrk_cleanup, child_wrk->wrk_index); done: if (old_sa.sa_flags & SA_SIGINFO) @@ -1473,6 +1741,11 @@ static void vls_incercept_sigchld () { struct sigaction sa; + if (old_sa.sa_sigaction) + { + VDBG (0, "have intercepted sigchld"); + return; + } clib_memset (&sa, 0, sizeof (sa)); sa.sa_sigaction = vls_intercept_sigchld_handler; sa.sa_flags = SA_SIGINFO; @@ -1518,17 +1791,18 @@ vls_app_fork_child_handler (void) * Allocate/initialize vls worker and share sessions */ vls_worker_alloc (); - parent_wrk = vcl_worker_get (parent_wrk_index); - vls_worker_copy_on_fork (parent_wrk); - parent_wrk->forked_child = vcl_get_worker_index (); /* Reset number of threads and set wrk index */ vlsl->vls_mt_n_threads = 0; vlsl->vls_wrk_index = vcl_get_worker_index (); vlsl->select_mp_check = 0; - vlsl->epoll_mp_check = 0; + clib_rwlock_init (&vlsl->vls_pool_lock); vls_mt_locks_init (); + parent_wrk = vcl_worker_get (parent_wrk_index); + vls_worker_copy_on_fork (parent_wrk); + parent_wrk->forked_child = vcl_get_worker_index (); + VDBG (0, "forked child main worker initialized"); vcm->forking = 0; } @@ -1546,6 +1820,9 @@ vls_app_exit (void) { vls_worker_t *wrk = vls_worker_get_current (); + /* Handle pending wrk cleanup */ + vls_handle_pending_wrk_cleanup (); + /* Unshare the sessions. VCL will clean up the worker */ vls_unshare_vcl_worker_sessions (vcl_worker_get_current ()); vls_worker_free (wrk); @@ -1560,24 +1837,33 @@ vls_clone_and_share_rpc_handler (void *args) vcl_worker_t *vcl_wrk = vcl_worker_get_current (), *dst_vcl_wrk; vcl_session_t *s, *dst_s; - vls = vls_session_get (wrk, msg->vls_index); - - if (!vls_mt_wrk_supported ()) - vls_init_share_session (wrk, vls); + VDBG (1, "process session clone of worker (session): %u (%u) -> %u (%u)", + vcl_wrk->wrk_index, msg->session_index, msg->origin_vcl_wrk, + msg->origin_session_index); - s = vcl_session_get (vcl_wrk, msg->session_index); - dst_wrk = vls_worker_get (msg->origin_vls_wrk); + /* VCL locked session can't been protected, so DONT touch it. + * VCL session may been free, check it. + */ dst_vcl_wrk = vcl_worker_get (msg->origin_vcl_wrk); - dst_vls = vls_session_get (dst_wrk, msg->origin_vls_index); - dst_vls->shared_data_index = vls->shared_data_index; + s = vcl_session_get (vcl_wrk, msg->session_index); + if (PREDICT_FALSE (!s)) + { + dst_vcl_wrk->rpc_done = VLS_RPC_STATE_SESSION_NOT_EXIST; + return; + } + + if (!vls_mt_wrk_supported ()) + { + vls = vls_session_get (wrk, msg->vls_index); + vls_init_share_session (wrk, vls); + dst_wrk = vls_worker_get (msg->origin_vls_wrk); + dst_vls = vls_session_get (dst_wrk, msg->origin_vls_index); + dst_vls->shared_data_index = vls->shared_data_index; + } dst_s = vcl_session_get (dst_vcl_wrk, msg->origin_session_index); clib_memcpy (dst_s, s, sizeof (*s)); - dst_vcl_wrk->rpc_done = 1; - - VDBG (1, "proces session clone of worker (session): %u (%u) -> %u (%u)", - vcl_wrk->wrk_index, msg->session_index, dst_vcl_wrk->wrk_index, - msg->origin_session_index); + dst_vcl_wrk->rpc_done = VLS_RPC_STATE_SUCCESS; } static void @@ -1585,14 +1871,14 @@ vls_session_cleanup_rpc_handler (void *args) { vls_sess_cleanup_msg_t *msg = (vls_sess_cleanup_msg_t *) args; vcl_worker_t *wrk = vcl_worker_get_current (); - vcl_worker_t *dst_wrk = vcl_worker_get (msg->origin_vcl_wrk); - - vppcom_session_close (vcl_session_handle_from_index (msg->session_index)); + vls_worker_t *vls_wrk = vls_worker_get_current (); + vcl_session_handle_t sh = vcl_session_handle_from_index (msg->session_index); - dst_wrk->rpc_done = 1; + VDBG (1, "process session cleanup of worker (session): %u (%u) from %u ()", + wrk->wrk_index, msg->session_index, msg->origin_vcl_wrk); - VDBG (1, "proces session cleanup of worker (session): %u (%u) from %u ()", - wrk->wrk_index, msg->session_index, dst_wrk->wrk_index); + vppcom_session_close (sh); + vls_sh_to_vlsh_table_del (vls_wrk, sh); } static void @@ -1613,34 +1899,42 @@ vls_rpc_handler (void *args) } void -vls_send_clone_and_share_rpc (vcl_worker_t * wrk, - vcl_locked_session_t * vls, u32 session_index, - u32 vls_wrk_index, u32 dst_wrk_index, - u32 dst_vls_index, u32 dst_session_index) +vls_send_clone_and_share_rpc (vcl_worker_t *wrk, u32 origin_vls_index, + u32 session_index, u32 vls_wrk_index, + u32 dst_wrk_index, u32 dst_vls_index, + u32 dst_session_index) { u8 data[sizeof (u8) + sizeof (vls_clone_and_share_msg_t)]; vls_clone_and_share_msg_t *msg; vls_rpc_msg_t *rpc; int ret; + f64 timeout = clib_time_now (&wrk->clib_time) + VLS_WORKER_RPC_TIMEOUT; rpc = (vls_rpc_msg_t *) & data; rpc->type = VLS_RPC_CLONE_AND_SHARE; msg = (vls_clone_and_share_msg_t *) & rpc->data; msg->origin_vls_wrk = vls_wrk_index; - msg->origin_vls_index = vls->vls_index; + msg->origin_vls_index = origin_vls_index; msg->origin_vcl_wrk = wrk->wrk_index; msg->origin_session_index = session_index; msg->vls_index = dst_vls_index; msg->session_index = dst_session_index; - wrk->rpc_done = 0; + /* Try lock and handle rpcs if two threads send each other + * clone requests at the same time. + */ + wrk->rpc_done = VLS_RPC_STATE_INIT; + while (!clib_spinlock_trylock (&vlsm->worker_rpc_lock)) + vcl_flush_mq_events (); ret = vcl_send_worker_rpc (dst_wrk_index, rpc, sizeof (data)); VDBG (1, "send session clone to wrk (session): %u (%u) -> %u (%u), ret=%d", dst_wrk_index, msg->session_index, msg->origin_vcl_wrk, msg->origin_session_index, ret); - while (!ret && !wrk->rpc_done) + while (!ret && wrk->rpc_done == VLS_RPC_STATE_INIT && + clib_time_now (&wrk->clib_time) < timeout) ; + clib_spinlock_unlock (&vlsm->worker_rpc_lock); } void @@ -1658,13 +1952,10 @@ vls_send_session_cleanup_rpc (vcl_worker_t * wrk, msg->origin_vcl_wrk = wrk->wrk_index; msg->session_index = dst_session_index; - wrk->rpc_done = 0; ret = vcl_send_worker_rpc (dst_wrk_index, rpc, sizeof (data)); VDBG (1, "send session cleanup to wrk (session): %u (%u) from %u, ret=%d", dst_wrk_index, msg->session_index, msg->origin_vcl_wrk, ret); - while (!ret && !wrk->rpc_done) - ; } int @@ -1677,8 +1968,8 @@ vls_app_create (char *app_name) vlsm = clib_mem_alloc (sizeof (vls_main_t)); clib_memset (vlsm, 0, sizeof (*vlsm)); - clib_rwlock_init (&vlsm->vls_table_lock); clib_rwlock_init (&vlsm->shared_data_lock); + clib_spinlock_init (&vlsm->worker_rpc_lock); pool_alloc (vlsm->workers, vcm->cfg.max_workers); pthread_atfork (vls_app_pre_fork, vls_app_fork_parent_handler, @@ -1686,6 +1977,7 @@ vls_app_create (char *app_name) atexit (vls_app_exit); vls_worker_alloc (); vlsl->vls_wrk_index = vcl_get_worker_index (); + clib_rwlock_init (&vlsl->vls_pool_lock); vls_mt_locks_init (); vcm->wrk_rpc_fn = vls_rpc_handler; return VPPCOM_OK;