From ea04e4c7c7f1116629b64ceb822c2423787fb6d4 Mon Sep 17 00:00:00 2001 From: Kurt Hackel Date: Fri, 1 Dec 2006 14:47:20 -0800 Subject: ocfs2_dlm: fix cluster-wide refcounting of lock resources This was previously broken and migration of some locks had to be temporarily disabled. We use a new (and backward-incompatible) set of network messages to account for all references to a lock resources held across the cluster. once these are all freed, the master node may then free the lock resource memory once its local references are dropped. Signed-off-by: Kurt Hackel Signed-off-by: Mark Fasheh --- fs/ocfs2/cluster/tcp_internal.h | 5 fs/ocfs2/dlm/dlmcommon.h | 75 +++++++ fs/ocfs2/dlm/dlmdebug.c | 18 ++ fs/ocfs2/dlm/dlmdomain.c | 117 +++++++++--- fs/ocfs2/dlm/dlmlock.c | 4 fs/ocfs2/dlm/dlmmaster.c | 394 +++++++++++++++++++++++++++++++++++---- fs/ocfs2/dlm/dlmrecovery.c | 123 +++++++++++- fs/ocfs2/dlm/dlmthread.c | 167 ++++++++--------- 8 files changed, 729 insertions(+), 174 deletions(-) diff --git a/fs/ocfs2/cluster/tcp_internal.h b/fs/ocfs2/cluster/tcp_internal.h index b700dc9..775c911 100644 --- a/fs/ocfs2/cluster/tcp_internal.h +++ b/fs/ocfs2/cluster/tcp_internal.h @@ -38,6 +38,9 @@ #define O2NET_QUORUM_DELAY_MS ((o2hb_dea * locking semantics of the file system using the protocol. It should * be somewhere else, I'm sure, but right now it isn't. * + * New in version 6: + * - DLM lockres remote refcount fixes. + * * New in version 5: * - Network timeout checking protocol * @@ -51,7 +54,7 @@ #define O2NET_QUORUM_DELAY_MS ((o2hb_dea * - full 64 bit i_size in the metadata lock lvbs * - introduction of "rw" lock and pushing meta/data locking down */ -#define O2NET_PROTOCOL_VERSION 5ULL +#define O2NET_PROTOCOL_VERSION 6ULL struct o2net_handshake { __be64 protocol_version; __be64 connector_id; diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h index 6b6ff76..9fa4271 100644 --- a/fs/ocfs2/dlm/dlmcommon.h +++ b/fs/ocfs2/dlm/dlmcommon.h @@ -222,6 +222,7 @@ #define DLM_LOCK_RES_READY #define DLM_LOCK_RES_DIRTY 0x00000008 #define DLM_LOCK_RES_IN_PROGRESS 0x00000010 #define DLM_LOCK_RES_MIGRATING 0x00000020 +#define DLM_LOCK_RES_DROPPING_REF 0x00000040 /* max milliseconds to wait to sync up a network failure with a node death */ #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000) @@ -265,6 +266,8 @@ struct dlm_lock_resource u8 owner; //node which owns the lock resource, or unknown u16 state; char lvb[DLM_LVB_LEN]; + unsigned int inflight_locks; + unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)]; }; struct dlm_migratable_lock @@ -367,7 +370,7 @@ enum { DLM_CONVERT_LOCK_MSG, /* 504 */ DLM_PROXY_AST_MSG, /* 505 */ DLM_UNLOCK_LOCK_MSG, /* 506 */ - DLM_UNUSED_MSG2, /* 507 */ + DLM_DEREF_LOCKRES_MSG, /* 507 */ DLM_MIGRATE_REQUEST_MSG, /* 508 */ DLM_MIG_LOCKRES_MSG, /* 509 */ DLM_QUERY_JOIN_MSG, /* 510 */ @@ -417,6 +420,9 @@ struct dlm_master_request u8 name[O2NM_MAX_NAME_LEN]; }; +#define DLM_ASSERT_RESPONSE_REASSERT 0x00000001 +#define DLM_ASSERT_RESPONSE_MASTERY_REF 0x00000002 + #define DLM_ASSERT_MASTER_MLE_CLEANUP 0x00000001 #define DLM_ASSERT_MASTER_REQUERY 0x00000002 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004 @@ -430,6 +436,8 @@ struct dlm_assert_master u8 name[O2NM_MAX_NAME_LEN]; }; +#define DLM_MIGRATE_RESPONSE_MASTERY_REF 0x00000001 + struct dlm_migrate_request { u8 master; @@ -648,6 +656,16 @@ struct dlm_finalize_reco __be32 pad2; }; +struct dlm_deref_lockres +{ + u32 pad1; + u16 pad2; + u8 node_idx; + u8 namelen; + + u8 name[O2NM_MAX_NAME_LEN]; +}; + static inline enum dlm_status __dlm_lockres_state_to_status(struct dlm_lock_resource *res) { @@ -721,8 +739,8 @@ void __dlm_lockres_calc_usage(struct dlm struct dlm_lock_resource *res); void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); -void dlm_purge_lockres(struct dlm_ctxt *dlm, - struct dlm_lock_resource *lockres); +int dlm_purge_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *lockres); static inline void dlm_lockres_get(struct dlm_lock_resource *res) { /* This is called on every lookup, so it might be worth @@ -733,6 +751,10 @@ void dlm_lockres_put(struct dlm_lock_res void __dlm_unhash_lockres(struct dlm_lock_resource *res); void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); +struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm, + const char *name, + unsigned int len, + unsigned int hash); struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, const char *name, unsigned int len, @@ -753,6 +775,47 @@ struct dlm_lock_resource *dlm_new_lockre const char *name, unsigned int namelen); +#define dlm_lockres_set_refmap_bit(bit,res) \ + __dlm_lockres_set_refmap_bit(bit,res,__FILE__,__LINE__) +#define dlm_lockres_clear_refmap_bit(bit,res) \ + __dlm_lockres_clear_refmap_bit(bit,res,__FILE__,__LINE__) + +static inline void __dlm_lockres_set_refmap_bit(int bit, + struct dlm_lock_resource *res, + const char *file, + int line) +{ + //printk("%s:%d:%.*s: setting bit %d\n", file, line, + // res->lockname.len, res->lockname.name, bit); + set_bit(bit, res->refmap); +} + +static inline void __dlm_lockres_clear_refmap_bit(int bit, + struct dlm_lock_resource *res, + const char *file, + int line) +{ + //printk("%s:%d:%.*s: clearing bit %d\n", file, line, + // res->lockname.len, res->lockname.name, bit); + clear_bit(bit, res->refmap); +} + +void __dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + const char *file, + int line); +void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + int new_lockres, + const char *file, + int line); +#define dlm_lockres_drop_inflight_ref(d,r) \ + __dlm_lockres_drop_inflight_ref(d,r,__FILE__,__LINE__) +#define dlm_lockres_grab_inflight_ref(d,r) \ + __dlm_lockres_grab_inflight_ref(d,r,0,__FILE__,__LINE__) +#define dlm_lockres_grab_inflight_ref_new(d,r) \ + __dlm_lockres_grab_inflight_ref(d,r,1,__FILE__,__LINE__) + void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock); void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock); void dlm_do_local_ast(struct dlm_ctxt *dlm, @@ -805,6 +868,7 @@ int dlm_lockres_is_dirty(struct dlm_ctxt int dlm_migrate_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, u8 target); +int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, u8 old_master); @@ -814,6 +878,7 @@ void __dlm_lockres_reserve_ast(struct dl int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data); int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data); int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data); int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data); int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data); @@ -856,10 +921,12 @@ static inline void __dlm_wait_on_lockres int dlm_init_mle_cache(void); void dlm_destroy_mle_cache(void); void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up); +int dlm_drop_lockres_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node); int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock); - +int __dlm_lockres_has_locks(struct dlm_lock_resource *res); int __dlm_lockres_unused(struct dlm_lock_resource *res); static inline const char * dlm_lock_mode_name(int mode) diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c index 3f6c8d8..1015cc7 100644 --- a/fs/ocfs2/dlm/dlmdebug.c +++ b/fs/ocfs2/dlm/dlmdebug.c @@ -53,6 +53,23 @@ void dlm_print_one_lock_resource(struct spin_unlock(&res->spinlock); } +static void dlm_print_lockres_refmap(struct dlm_lock_resource *res) +{ + int bit; + assert_spin_locked(&res->spinlock); + + mlog(ML_NOTICE, " refmap nodes: [ "); + bit = 0; + while (1) { + bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit); + if (bit >= O2NM_MAX_NODES) + break; + printk("%u ", bit); + bit++; + } + printk("], inflight=%u\n", res->inflight_locks); +} + void __dlm_print_one_lock_resource(struct dlm_lock_resource *res) { struct list_head *iter2; @@ -65,6 +82,7 @@ void __dlm_print_one_lock_resource(struc res->owner, res->state); mlog(ML_NOTICE, " last used: %lu, on purge list: %s\n", res->last_used, list_empty(&res->purge) ? "no" : "yes"); + dlm_print_lockres_refmap(res); mlog(ML_NOTICE, " granted queue: \n"); list_for_each(iter2, &res->granted) { lock = list_entry(iter2, struct dlm_lock, list); diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c index f0b25f2..3995de3 100644 --- a/fs/ocfs2/dlm/dlmdomain.c +++ b/fs/ocfs2/dlm/dlmdomain.c @@ -125,10 +125,10 @@ void __dlm_insert_lockres(struct dlm_ctx hlist_add_head(&res->hash_node, bucket); } -struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, - const char *name, - unsigned int len, - unsigned int hash) +struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm, + const char *name, + unsigned int len, + unsigned int hash) { struct hlist_head *bucket; struct hlist_node *list; @@ -154,6 +154,37 @@ struct dlm_lock_resource * __dlm_lookup_ return NULL; } +/* intended to be called by functions which do not care about lock + * resources which are being purged (most net _handler functions). + * this will return NULL for any lock resource which is found but + * currently in the process of dropping its mastery reference. + * use __dlm_lookup_lockres_full when you need the lock resource + * regardless (e.g. dlm_get_lock_resource) */ +struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len, + unsigned int hash) +{ + struct dlm_lock_resource *res = NULL; + + mlog_entry("%.*s\n", len, name); + + assert_spin_locked(&dlm->spinlock); + + res = __dlm_lookup_lockres_full(dlm, name, len, hash); + if (res) { + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_DROPPING_REF) { + spin_unlock(&res->spinlock); + dlm_lockres_put(res); + return NULL; + } + spin_unlock(&res->spinlock); + } + + return res; +} + struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm, const char *name, unsigned int len) @@ -330,43 +361,60 @@ static void dlm_complete_dlm_shutdown(st wake_up(&dlm_domain_events); } -static void dlm_migrate_all_locks(struct dlm_ctxt *dlm) +static int dlm_migrate_all_locks(struct dlm_ctxt *dlm) { - int i; + int i, num, n, ret = 0; struct dlm_lock_resource *res; + struct hlist_node *iter; + struct hlist_head *bucket; + int dropped; mlog(0, "Migrating locks from domain %s\n", dlm->name); -restart: + + num = 0; spin_lock(&dlm->spinlock); for (i = 0; i < DLM_HASH_BUCKETS; i++) { - while (!hlist_empty(dlm_lockres_hash(dlm, i))) { - res = hlist_entry(dlm_lockres_hash(dlm, i)->first, - struct dlm_lock_resource, hash_node); - /* need reference when manually grabbing lockres */ +redo_bucket: + n = 0; + bucket = dlm_lockres_hash(dlm, i); + iter = bucket->first; + while (iter) { + n++; + res = hlist_entry(iter, struct dlm_lock_resource, + hash_node); dlm_lockres_get(res); - /* this should unhash the lockres - * and exit with dlm->spinlock */ - mlog(0, "purging res=%p\n", res); - if (dlm_lockres_is_dirty(dlm, res)) { - /* HACK! this should absolutely go. - * need to figure out why some empty - * lockreses are still marked dirty */ - mlog(ML_ERROR, "lockres %.*s dirty!\n", - res->lockname.len, res->lockname.name); - - spin_unlock(&dlm->spinlock); - dlm_kick_thread(dlm, res); - wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res)); - dlm_lockres_put(res); - goto restart; - } - dlm_purge_lockres(dlm, res); + /* migrate, if necessary. this will drop the dlm + * spinlock and retake it if it does migration. */ + dropped = dlm_empty_lockres(dlm, res); + + spin_lock(&res->spinlock); + __dlm_lockres_calc_usage(dlm, res); + iter = res->hash_node.next; + spin_unlock(&res->spinlock); + dlm_lockres_put(res); + + cond_resched_lock(&dlm->spinlock); + + if (dropped) + goto redo_bucket; } + num += n; + mlog(0, "%s: touched %d lockreses in bucket %d " + "(tot=%d)\n", dlm->name, n, i, num); } spin_unlock(&dlm->spinlock); - + wake_up(&dlm->dlm_thread_wq); + + /* let the dlm thread take care of purging, keep scanning until + * nothing remains in the hash */ + if (num) { + mlog(0, "%s: %d lock resources in hash last pass\n", + dlm->name, num); + ret = -EAGAIN; + } mlog(0, "DONE Migrating locks from domain %s\n", dlm->name); + return ret; } static int dlm_no_joining_node(struct dlm_ctxt *dlm) @@ -571,7 +619,9 @@ void dlm_unregister_domain(struct dlm_ct /* We changed dlm state, notify the thread */ dlm_kick_thread(dlm, NULL); - dlm_migrate_all_locks(dlm); + while (dlm_migrate_all_locks(dlm)) { + mlog(0, "%s: more migration to do\n", dlm->name); + } dlm_mark_domain_leaving(dlm); dlm_leave_domain(dlm); dlm_complete_dlm_shutdown(dlm); @@ -1082,6 +1132,13 @@ static int dlm_register_domain_handlers( if (status) goto bail; + status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key, + sizeof(struct dlm_deref_lockres), + dlm_deref_lockres_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key, sizeof(struct dlm_migrate_request), dlm_migrate_request_handler, diff --git a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c index e5ca3db..ac91a76 100644 --- a/fs/ocfs2/dlm/dlmlock.c +++ b/fs/ocfs2/dlm/dlmlock.c @@ -163,6 +163,10 @@ static enum dlm_status dlmlock_master(st kick_thread = 1; } } + /* reduce the inflight count, this may result in the lockres + * being purged below during calc_usage */ + if (lock->ml.node == dlm->node_num) + dlm_lockres_drop_inflight_ref(dlm, res); spin_unlock(&res->spinlock); wake_up(&res->wq); diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index 0ad8720..4645ec2 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -99,9 +99,9 @@ static void dlm_mle_node_up(struct dlm_c int idx); static void dlm_assert_master_worker(struct dlm_work_item *item, void *data); -static int dlm_do_assert_master(struct dlm_ctxt *dlm, const char *lockname, - unsigned int namelen, void *nodemap, - u32 flags); +static int dlm_do_assert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + void *nodemap, u32 flags); static inline int dlm_mle_equal(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle, @@ -237,7 +237,8 @@ static int dlm_find_mle(struct dlm_ctxt struct dlm_master_list_entry **mle, char *name, unsigned int namelen); -static int dlm_do_master_request(struct dlm_master_list_entry *mle, int to); +static int dlm_do_master_request(struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, int to); static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm, @@ -687,6 +688,7 @@ static void dlm_init_lockres(struct dlm_ INIT_LIST_HEAD(&res->purge); atomic_set(&res->asts_reserved, 0); res->migration_pending = 0; + res->inflight_locks = 0; kref_init(&res->refs); @@ -700,6 +702,7 @@ static void dlm_init_lockres(struct dlm_ res->last_used = 0; memset(res->lvb, 0, DLM_LVB_LEN); + memset(res->refmap, 0, sizeof(res->refmap)); } struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm, @@ -722,6 +725,42 @@ struct dlm_lock_resource *dlm_new_lockre return res; } +void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + int new_lockres, + const char *file, + int line) +{ + if (!new_lockres) + assert_spin_locked(&res->spinlock); + + if (!test_bit(dlm->node_num, res->refmap)) { + BUG_ON(res->inflight_locks != 0); + dlm_lockres_set_refmap_bit(dlm->node_num, res); + } + res->inflight_locks++; + mlog(0, "%s:%.*s: inflight++: now %u\n", + dlm->name, res->lockname.len, res->lockname.name, + res->inflight_locks); +} + +void __dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + const char *file, + int line) +{ + assert_spin_locked(&res->spinlock); + + BUG_ON(res->inflight_locks == 0); + res->inflight_locks--; + mlog(0, "%s:%.*s: inflight--: now %u\n", + dlm->name, res->lockname.len, res->lockname.name, + res->inflight_locks); + if (res->inflight_locks == 0) + dlm_lockres_clear_refmap_bit(dlm->node_num, res); + wake_up(&res->wq); +} + /* * lookup a lock resource by name. * may already exist in the hashtable. @@ -752,6 +791,7 @@ struct dlm_lock_resource * dlm_get_lock_ unsigned int hash; int tries = 0; int bit, wait_on_recovery = 0; + int drop_inflight_if_nonlocal = 0; BUG_ON(!lockid); @@ -761,9 +801,30 @@ struct dlm_lock_resource * dlm_get_lock_ lookup: spin_lock(&dlm->spinlock); - tmpres = __dlm_lookup_lockres(dlm, lockid, namelen, hash); + tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash); if (tmpres) { + int dropping_ref = 0; + + spin_lock(&tmpres->spinlock); + if (tmpres->owner == dlm->node_num) { + BUG_ON(tmpres->state & DLM_LOCK_RES_DROPPING_REF); + dlm_lockres_grab_inflight_ref(dlm, tmpres); + } else if (tmpres->state & DLM_LOCK_RES_DROPPING_REF) + dropping_ref = 1; + spin_unlock(&tmpres->spinlock); spin_unlock(&dlm->spinlock); + + /* wait until done messaging the master, drop our ref to allow + * the lockres to be purged, start over. */ + if (dropping_ref) { + spin_lock(&tmpres->spinlock); + __dlm_wait_on_lockres_flags(tmpres, DLM_LOCK_RES_DROPPING_REF); + spin_unlock(&tmpres->spinlock); + dlm_lockres_put(tmpres); + tmpres = NULL; + goto lookup; + } + mlog(0, "found in hash!\n"); if (res) dlm_lockres_put(res); @@ -793,6 +854,7 @@ lookup: spin_lock(&res->spinlock); dlm_change_lockres_owner(dlm, res, dlm->node_num); __dlm_insert_lockres(dlm, res); + dlm_lockres_grab_inflight_ref(dlm, res); spin_unlock(&res->spinlock); spin_unlock(&dlm->spinlock); /* lockres still marked IN_PROGRESS */ @@ -805,29 +867,40 @@ lookup: /* if we found a block, wait for lock to be mastered by another node */ blocked = dlm_find_mle(dlm, &mle, (char *)lockid, namelen); if (blocked) { + int mig; if (mle->type == DLM_MLE_MASTER) { mlog(ML_ERROR, "master entry for nonexistent lock!\n"); BUG(); - } else if (mle->type == DLM_MLE_MIGRATION) { - /* migration is in progress! */ - /* the good news is that we now know the - * "current" master (mle->master). */ - + } + mig = (mle->type == DLM_MLE_MIGRATION); + /* if there is a migration in progress, let the migration + * finish before continuing. we can wait for the absence + * of the MIGRATION mle: either the migrate finished or + * one of the nodes died and the mle was cleaned up. + * if there is a BLOCK here, but it already has a master + * set, we are too late. the master does not have a ref + * for us in the refmap. detach the mle and drop it. + * either way, go back to the top and start over. */ + if (mig || mle->master != O2NM_MAX_NODES) { + BUG_ON(mig && mle->master == dlm->node_num); + /* we arrived too late. the master does not + * have a ref for us. retry. */ + mlog(0, "%s:%.*s: late on %s\n", + dlm->name, namelen, lockid, + mig ? "MIGRATION" : "BLOCK"); spin_unlock(&dlm->master_lock); - assert_spin_locked(&dlm->spinlock); - - /* set the lockres owner and hash it */ - spin_lock(&res->spinlock); - dlm_set_lockres_owner(dlm, res, mle->master); - __dlm_insert_lockres(dlm, res); - spin_unlock(&res->spinlock); spin_unlock(&dlm->spinlock); /* master is known, detach */ - dlm_mle_detach_hb_events(dlm, mle); + if (!mig) + dlm_mle_detach_hb_events(dlm, mle); dlm_put_mle(mle); mle = NULL; - goto wake_waiters; + /* this is lame, but we cant wait on either + * the mle or lockres waitqueue here */ + if (mig) + msleep(100); + goto lookup; } } else { /* go ahead and try to master lock on this node */ @@ -858,6 +931,13 @@ lookup: /* finally add the lockres to its hash bucket */ __dlm_insert_lockres(dlm, res); + /* since this lockres is new it doesnt not require the spinlock */ + dlm_lockres_grab_inflight_ref_new(dlm, res); + + /* if this node does not become the master make sure to drop + * this inflight reference below */ + drop_inflight_if_nonlocal = 1; + /* get an extra ref on the mle in case this is a BLOCK * if so, the creator of the BLOCK may try to put the last * ref at this time in the assert master handler, so we @@ -910,7 +990,7 @@ redo_request: ret = -EINVAL; dlm_node_iter_init(mle->vote_map, &iter); while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { - ret = dlm_do_master_request(mle, nodenum); + ret = dlm_do_master_request(res, mle, nodenum); if (ret < 0) mlog_errno(ret); if (mle->master != O2NM_MAX_NODES) { @@ -960,6 +1040,8 @@ wait: wake_waiters: spin_lock(&res->spinlock); + if (res->owner != dlm->node_num && drop_inflight_if_nonlocal) + dlm_lockres_drop_inflight_ref(dlm, res); res->state &= ~DLM_LOCK_RES_IN_PROGRESS; spin_unlock(&res->spinlock); wake_up(&res->wq); @@ -998,7 +1080,7 @@ recheck: /* this will cause the master to re-assert across * the whole cluster, freeing up mles */ if (res->owner != dlm->node_num) { - ret = dlm_do_master_request(mle, res->owner); + ret = dlm_do_master_request(res, mle, res->owner); if (ret < 0) { /* give recovery a chance to run */ mlog(ML_ERROR, "link to %u went down?: %d\n", res->owner, ret); @@ -1062,6 +1144,8 @@ recheck: * now tell other nodes that I am * mastering this. */ mle->master = dlm->node_num; + /* ref was grabbed in get_lock_resource + * will be dropped in dlmlock_master */ assert = 1; sleep = 0; } @@ -1087,7 +1171,8 @@ recheck: (atomic_read(&mle->woken) == 1), timeo); if (res->owner == O2NM_MAX_NODES) { - mlog(0, "waiting again\n"); + mlog(0, "%s:%.*s: waiting again\n", dlm->name, + res->lockname.len, res->lockname.name); goto recheck; } mlog(0, "done waiting, master is %u\n", res->owner); @@ -1100,8 +1185,7 @@ recheck: m = dlm->node_num; mlog(0, "about to master %.*s here, this=%u\n", res->lockname.len, res->lockname.name, m); - ret = dlm_do_assert_master(dlm, res->lockname.name, - res->lockname.len, mle->vote_map, 0); + ret = dlm_do_assert_master(dlm, res, mle->vote_map, 0); if (ret) { /* This is a failure in the network path, * not in the response to the assert_master @@ -1117,6 +1201,8 @@ recheck: /* set the lockres owner */ spin_lock(&res->spinlock); + /* mastery reference obtained either during + * assert_master_handler or in get_lock_resource */ dlm_change_lockres_owner(dlm, res, m); spin_unlock(&res->spinlock); @@ -1283,7 +1369,8 @@ static int dlm_restart_lock_mastery(stru * */ -static int dlm_do_master_request(struct dlm_master_list_entry *mle, int to) +static int dlm_do_master_request(struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, int to) { struct dlm_ctxt *dlm = mle->dlm; struct dlm_master_request request; @@ -1339,6 +1426,9 @@ again: case DLM_MASTER_RESP_YES: set_bit(to, mle->response_map); mlog(0, "node %u is the master, response=YES\n", to); + mlog(0, "%s:%.*s: master node %u now knows I have a " + "reference\n", dlm->name, res->lockname.len, + res->lockname.name, to); mle->master = to; break; case DLM_MASTER_RESP_NO: @@ -1428,8 +1518,10 @@ way_up_top: } if (res->owner == dlm->node_num) { + mlog(0, "%s:%.*s: setting bit %u in refmap\n", + dlm->name, namelen, name, request->node_idx); + dlm_lockres_set_refmap_bit(request->node_idx, res); spin_unlock(&res->spinlock); - // mlog(0, "this node is the master\n"); response = DLM_MASTER_RESP_YES; if (mle) kmem_cache_free(dlm_mle_cache, mle); @@ -1477,7 +1569,6 @@ way_up_top: mlog(0, "node %u is master, but trying to migrate to " "node %u.\n", tmpmle->master, tmpmle->new_master); if (tmpmle->master == dlm->node_num) { - response = DLM_MASTER_RESP_YES; mlog(ML_ERROR, "no owner on lockres, but this " "node is trying to migrate it to %u?!\n", tmpmle->new_master); @@ -1494,6 +1585,10 @@ way_up_top: * go back and clean the mles on any * other nodes */ dispatch_assert = 1; + dlm_lockres_set_refmap_bit(request->node_idx, res); + mlog(0, "%s:%.*s: setting bit %u in refmap\n", + dlm->name, namelen, name, + request->node_idx); } else response = DLM_MASTER_RESP_NO; } else { @@ -1607,15 +1702,17 @@ send_response: * can periodically run all locks owned by this node * and re-assert across the cluster... */ -static int dlm_do_assert_master(struct dlm_ctxt *dlm, const char *lockname, - unsigned int namelen, void *nodemap, - u32 flags) +int dlm_do_assert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + void *nodemap, u32 flags) { struct dlm_assert_master assert; int to, tmpret; struct dlm_node_iter iter; int ret = 0; int reassert; + const char *lockname = res->lockname.name; + unsigned int namelen = res->lockname.len; BUG_ON(namelen > O2NM_MAX_NAME_LEN); again: @@ -1647,6 +1744,7 @@ again: mlog(0, "link to %d went down!\n", to); /* any nonzero status return will do */ ret = tmpret; + r = 0; } else if (r < 0) { /* ok, something horribly messed. kill thyself. */ mlog(ML_ERROR,"during assert master of %.*s to %u, " @@ -1661,12 +1759,29 @@ again: spin_unlock(&dlm->master_lock); spin_unlock(&dlm->spinlock); BUG(); - } else if (r == EAGAIN) { + } + + if (r & DLM_ASSERT_RESPONSE_REASSERT && + !(r & DLM_ASSERT_RESPONSE_MASTERY_REF)) { + mlog(ML_ERROR, "%.*s: very strange, " + "master MLE but no lockres on %u\n", + namelen, lockname, to); + } + + if (r & DLM_ASSERT_RESPONSE_REASSERT) { mlog(0, "%.*s: node %u create mles on other " "nodes and requests a re-assert\n", namelen, lockname, to); reassert = 1; } + if (r & DLM_ASSERT_RESPONSE_MASTERY_REF) { + mlog(0, "%.*s: node %u has a reference to this " + "lockres, set the bit in the refmap\n", + namelen, lockname, to); + spin_lock(&res->spinlock); + dlm_lockres_set_refmap_bit(to, res); + spin_unlock(&res->spinlock); + } } if (reassert) @@ -1693,7 +1808,7 @@ int dlm_assert_master_handler(struct o2n char *name; unsigned int namelen, hash; u32 flags; - int master_request = 0; + int master_request = 0, have_lockres_ref = 0; int ret = 0; if (!dlm_grab(dlm)) @@ -1864,6 +1979,7 @@ ok: dlm_change_lockres_owner(dlm, res, mle->master); } spin_unlock(&res->spinlock); + have_lockres_ref = 1; } /* master is known, detach if not already detached. @@ -1918,7 +2034,19 @@ done: dlm_put(dlm); if (master_request) { mlog(0, "need to tell master to reassert\n"); - ret = EAGAIN; // positive. negative would shoot down the node. + /* positive. negative would shoot down the node. */ + ret |= DLM_ASSERT_RESPONSE_REASSERT; + if (!have_lockres_ref) { + mlog(ML_ERROR, "strange, got assert from %u, MASTER " + "mle present here for %s:%.*s, but no lockres!\n", + assert->node_idx, dlm->name, namelen, name); + } + } + if (have_lockres_ref) { + /* let the master know we have a reference to the lockres */ + ret |= DLM_ASSERT_RESPONSE_MASTERY_REF; + mlog(0, "%s:%.*s: got assert from %u, need a ref\n", + dlm->name, namelen, name, assert->node_idx); } return ret; @@ -2023,9 +2151,7 @@ static void dlm_assert_master_worker(str * even if one or more nodes die */ mlog(0, "worker about to master %.*s here, this=%u\n", res->lockname.len, res->lockname.name, dlm->node_num); - ret = dlm_do_assert_master(dlm, res->lockname.name, - res->lockname.len, - nodemap, flags); + ret = dlm_do_assert_master(dlm, res, nodemap, flags); if (ret < 0) { /* no need to restart, we are done */ if (!dlm_is_host_down(ret)) @@ -2097,6 +2223,104 @@ static int dlm_pre_master_reco_lockres(s return ret; } +/* + * DLM_DEREF_LOCKRES_MSG + */ + +int dlm_drop_lockres_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + struct dlm_deref_lockres deref; + int ret = 0, r; + const char *lockname; + unsigned int namelen; + + lockname = res->lockname.name; + namelen = res->lockname.len; + BUG_ON(namelen > O2NM_MAX_NAME_LEN); + + mlog(0, "%s:%.*s: sending deref to %d\n", + dlm->name, namelen, lockname, res->owner); + memset(&deref, 0, sizeof(deref)); + deref.node_idx = dlm->node_num; + deref.namelen = namelen; + memcpy(deref.name, lockname, namelen); + + ret = o2net_send_message(DLM_DEREF_LOCKRES_MSG, dlm->key, + &deref, sizeof(deref), res->owner, &r); + if (ret < 0) + mlog_errno(ret); + else if (r < 0) { + /* BAD. other node says I did not have a ref. */ + mlog(ML_ERROR,"while dropping ref on %s:%.*s " + "(master=%u) got %d.\n", dlm->name, namelen, + lockname, res->owner, r); + dlm_print_one_lock_resource(res); + BUG(); + } + return ret; +} + +int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_deref_lockres *deref = (struct dlm_deref_lockres *)msg->buf; + struct dlm_lock_resource *res = NULL; + char *name; + unsigned int namelen; + int ret = -EINVAL; + u8 node; + unsigned int hash; + + if (!dlm_grab(dlm)) + return 0; + + name = deref->name; + namelen = deref->namelen; + node = deref->node_idx; + + if (namelen > DLM_LOCKID_NAME_MAX) { + mlog(ML_ERROR, "Invalid name length!"); + goto done; + } + if (deref->node_idx >= O2NM_MAX_NODES) { + mlog(ML_ERROR, "Invalid node number: %u\n", node); + goto done; + } + + hash = dlm_lockid_hash(name, namelen); + + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres_full(dlm, name, namelen, hash); + if (!res) { + spin_unlock(&dlm->spinlock); + mlog(ML_ERROR, "%s:%.*s: bad lockres name\n", + dlm->name, namelen, name); + goto done; + } + spin_unlock(&dlm->spinlock); + + spin_lock(&res->spinlock); + BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF); + if (test_bit(node, res->refmap)) { + ret = 0; + dlm_lockres_clear_refmap_bit(node, res); + } else { + mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref " + "but it is already dropped!\n", dlm->name, namelen, + name, node); + __dlm_print_one_lock_resource(res); + } + spin_unlock(&res->spinlock); + + if (!ret) + dlm_lockres_calc_usage(dlm, res); +done: + if (res) + dlm_lockres_put(res); + dlm_put(dlm); + return ret; +} + /* * DLM_MIGRATE_LOCKRES @@ -2376,6 +2600,53 @@ leave: return ret; } +#define DLM_MIGRATION_RETRY_MS 100 + +/* Should be called only after beginning the domain leave process. + * There should not be any remaining locks on nonlocal lock resources, + * and there should be no local locks left on locally mastered resources. + * + * Called with the dlm spinlock held, may drop it to do migration, but + * will re-acquire before exit. + * + * Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped */ +int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + int ret; + int lock_dropped = 0; + + if (res->owner != dlm->node_num) { + if (!__dlm_lockres_unused(res)) { + mlog(ML_ERROR, "%s:%.*s: this node is not master, " + "trying to free this but locks remain\n", + dlm->name, res->lockname.len, res->lockname.name); + } + goto leave; + } + + /* Wheee! Migrate lockres here! Will sleep so drop spinlock. */ + spin_unlock(&dlm->spinlock); + lock_dropped = 1; + while (1) { + ret = dlm_migrate_lockres(dlm, res, O2NM_MAX_NODES); + if (ret >= 0) + break; + if (ret == -ENOTEMPTY) { + mlog(ML_ERROR, "lockres %.*s still has local locks!\n", + res->lockname.len, res->lockname.name); + BUG(); + } + + mlog(0, "lockres %.*s: migrate failed, " + "retrying\n", res->lockname.len, + res->lockname.name); + msleep(DLM_MIGRATION_RETRY_MS); + } + spin_lock(&dlm->spinlock); +leave: + return lock_dropped; +} + int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock) { int ret; @@ -2490,7 +2761,7 @@ static void dlm_remove_nonlocal_locks(st { struct list_head *iter, *iter2; struct list_head *queue = &res->granted; - int i; + int i, bit; struct dlm_lock *lock; assert_spin_locked(&res->spinlock); @@ -2508,12 +2779,28 @@ static void dlm_remove_nonlocal_locks(st BUG_ON(!list_empty(&lock->bast_list)); BUG_ON(lock->ast_pending); BUG_ON(lock->bast_pending); + dlm_lockres_clear_refmap_bit(lock->ml.node, res); list_del_init(&lock->list); dlm_lock_put(lock); } } queue++; } + bit = 0; + while (1) { + bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit); + if (bit >= O2NM_MAX_NODES) + break; + /* do not clear the local node reference, if there is a + * process holding this, let it drop the ref itself */ + if (bit != dlm->node_num) { + mlog(0, "%s:%.*s: node %u had a ref to this " + "migrating lockres, clearing\n", dlm->name, + res->lockname.len, res->lockname.name, bit); + dlm_lockres_clear_refmap_bit(bit, res); + } + bit++; + } } /* for now this is not too intelligent. we will @@ -2601,6 +2888,16 @@ static int dlm_do_migrate_request(struct mlog(0, "migrate request (node %u) returned %d!\n", nodenum, status); ret = status; + } else if (status == DLM_MIGRATE_RESPONSE_MASTERY_REF) { + /* during the migration request we short-circuited + * the mastery of the lockres. make sure we have + * a mastery ref for nodenum */ + mlog(0, "%s:%.*s: need ref for node %u\n", + dlm->name, res->lockname.len, res->lockname.name, + nodenum); + spin_lock(&res->spinlock); + dlm_lockres_set_refmap_bit(nodenum, res); + spin_unlock(&res->spinlock); } } @@ -2745,7 +3042,13 @@ static int dlm_add_migration_mle(struct /* remove it from the list so that only one * mle will be found */ list_del_init(&tmp->list); - __dlm_mle_detach_hb_events(dlm, mle); + /* this was obviously WRONG. mle is uninited here. should be tmp. */ + __dlm_mle_detach_hb_events(dlm, tmp); + ret = DLM_MIGRATE_RESPONSE_MASTERY_REF; + mlog(0, "%s:%.*s: master=%u, newmaster=%u, " + "telling master to get ref for cleared out mle " + "during migration\n", dlm->name, namelen, name, + master, new_master); } spin_unlock(&tmp->spinlock); } @@ -2753,6 +3056,8 @@ static int dlm_add_migration_mle(struct /* now add a migration mle to the tail of the list */ dlm_init_mle(mle, DLM_MLE_MIGRATION, dlm, res, name, namelen); mle->new_master = new_master; + /* the new master will be sending an assert master for this. + * at that point we will get the refmap reference */ mle->master = master; /* do this for consistency with other mle types */ set_bit(new_master, mle->maybe_map); @@ -2902,6 +3207,13 @@ int dlm_finish_migration(struct dlm_ctxt clear_bit(dlm->node_num, iter.node_map); spin_unlock(&dlm->spinlock); + /* ownership of the lockres is changing. account for the + * mastery reference here since old_master will briefly have + * a reference after the migration completes */ + spin_lock(&res->spinlock); + dlm_lockres_set_refmap_bit(old_master, res); + spin_unlock(&res->spinlock); + mlog(0, "now time to do a migrate request to other nodes\n"); ret = dlm_do_migrate_request(dlm, res, old_master, dlm->node_num, &iter); @@ -2914,8 +3226,7 @@ int dlm_finish_migration(struct dlm_ctxt res->lockname.len, res->lockname.name); /* this call now finishes out the nodemap * even if one or more nodes die */ - ret = dlm_do_assert_master(dlm, res->lockname.name, - res->lockname.len, iter.node_map, + ret = dlm_do_assert_master(dlm, res, iter.node_map, DLM_ASSERT_MASTER_FINISH_MIGRATION); if (ret < 0) { /* no longer need to retry. all living nodes contacted. */ @@ -2927,8 +3238,7 @@ int dlm_finish_migration(struct dlm_ctxt set_bit(old_master, iter.node_map); mlog(0, "doing assert master of %.*s back to %u\n", res->lockname.len, res->lockname.name, old_master); - ret = dlm_do_assert_master(dlm, res->lockname.name, - res->lockname.len, iter.node_map, + ret = dlm_do_assert_master(dlm, res, iter.node_map, DLM_ASSERT_MASTER_FINISH_MIGRATION); if (ret < 0) { mlog(0, "assert master to original master failed " diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index 367a11e..d011a2a 100644 --- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1129,6 +1129,11 @@ static int dlm_send_mig_lockres_msg(stru if (total_locks == mres_total_locks) mres->flags |= DLM_MRES_ALL_DONE; + mlog(0, "%s:%.*s: sending mig lockres (%s) to %u\n", + dlm->name, res->lockname.len, res->lockname.name, + orig_flags & DLM_MRES_MIGRATION ? "migrate" : "recovery", + send_to); + /* send it */ ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres, sz, send_to, &status); @@ -1213,6 +1218,34 @@ static int dlm_add_lock_to_array(struct return 0; } +static void dlm_add_dummy_lock(struct dlm_ctxt *dlm, + struct dlm_migratable_lockres *mres) +{ + struct dlm_lock dummy; + memset(&dummy, 0, sizeof(dummy)); + dummy.ml.cookie = 0; + dummy.ml.type = LKM_IVMODE; + dummy.ml.convert_type = LKM_IVMODE; + dummy.ml.highest_blocked = LKM_IVMODE; + dummy.lksb = NULL; + dummy.ml.node = dlm->node_num; + dlm_add_lock_to_array(&dummy, mres, DLM_BLOCKED_LIST); +} + +static inline int dlm_is_dummy_lock(struct dlm_ctxt *dlm, + struct dlm_migratable_lock *ml, + u8 *nodenum) +{ + if (unlikely(ml->cookie == 0 && + ml->type == LKM_IVMODE && + ml->convert_type == LKM_IVMODE && + ml->highest_blocked == LKM_IVMODE && + ml->list == DLM_BLOCKED_LIST)) { + *nodenum = ml->node; + return 1; + } + return 0; +} int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, struct dlm_migratable_lockres *mres, @@ -1260,6 +1293,14 @@ int dlm_send_one_lockres(struct dlm_ctxt goto error; } } + if (total_locks == 0) { + /* send a dummy lock to indicate a mastery reference only */ + mlog(0, "%s:%.*s: sending dummy lock to %u, %s\n", + dlm->name, res->lockname.len, res->lockname.name, + send_to, flags & DLM_MRES_RECOVERY ? "recovery" : + "migration"); + dlm_add_dummy_lock(dlm, mres); + } /* flush any remaining locks */ ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks); if (ret < 0) @@ -1386,13 +1427,16 @@ int dlm_mig_lockres_handler(struct o2net /* add an extra ref for just-allocated lockres * otherwise the lockres will be purged immediately */ dlm_lockres_get(res); - } /* at this point we have allocated everything we need, * and we have a hashed lockres with an extra ref and * the proper res->state flags. */ ret = 0; + spin_lock(&res->spinlock); + /* drop this either when master requery finds a different master + * or when a lock is added by the recovery worker */ + dlm_lockres_grab_inflight_ref(dlm, res); if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) { /* migration cannot have an unknown master */ BUG_ON(!(mres->flags & DLM_MRES_RECOVERY)); @@ -1400,10 +1444,11 @@ int dlm_mig_lockres_handler(struct o2net "unknown owner.. will need to requery: " "%.*s\n", mres->lockname_len, mres->lockname); } else { - spin_lock(&res->spinlock); + /* take a reference now to pin the lockres, drop it + * when locks are added in the worker */ dlm_change_lockres_owner(dlm, res, dlm->node_num); - spin_unlock(&res->spinlock); } + spin_unlock(&res->spinlock); /* queue up work for dlm_mig_lockres_worker */ dlm_grab(dlm); /* get an extra ref for the work item */ @@ -1459,6 +1504,9 @@ again: "this node will take it.\n", res->lockname.len, res->lockname.name); } else { + spin_lock(&res->spinlock); + dlm_lockres_drop_inflight_ref(dlm, res); + spin_unlock(&res->spinlock); mlog(0, "master needs to respond to sender " "that node %u still owns %.*s\n", real_master, res->lockname.len, @@ -1666,10 +1714,25 @@ static int dlm_process_recovery_data(str int i, bad; struct list_head *iter; struct dlm_lock *lock = NULL; + u8 from = O2NM_MAX_NODES; + unsigned int added = 0; mlog(0, "running %d locks for this lockres\n", mres->num_locks); for (i=0; inum_locks; i++) { ml = &(mres->ml[i]); + + if (dlm_is_dummy_lock(dlm, ml, &from)) { + /* placeholder, just need to set the refmap bit */ + BUG_ON(mres->num_locks != 1); + mlog(0, "%s:%.*s: dummy lock for %u\n", + dlm->name, mres->lockname_len, mres->lockname, + from); + spin_lock(&res->spinlock); + dlm_lockres_set_refmap_bit(from, res); + spin_unlock(&res->spinlock); + added++; + break; + } BUG_ON(ml->highest_blocked != LKM_IVMODE); newlock = NULL; lksb = NULL; @@ -1711,6 +1774,7 @@ static int dlm_process_recovery_data(str /* do not alter lock refcount. switching lists. */ list_move_tail(&lock->list, queue); spin_unlock(&res->spinlock); + added++; mlog(0, "just reordered a local lock!\n"); continue; @@ -1817,12 +1881,24 @@ skip_lvb: if (!bad) { dlm_lock_get(newlock); list_add_tail(&newlock->list, queue); + mlog(0, "%s:%.*s: added lock for node %u, " + "setting refmap bit\n", dlm->name, + res->lockname.len, res->lockname.name, ml->node); + dlm_lockres_set_refmap_bit(ml->node, res); + added++; } spin_unlock(&res->spinlock); } mlog(0, "done running all the locks\n"); leave: + /* balance the ref taken when the work was queued */ + if (added > 0) { + spin_lock(&res->spinlock); + dlm_lockres_drop_inflight_ref(dlm, res); + spin_unlock(&res->spinlock); + } + if (ret < 0) { mlog_errno(ret); if (newlock) @@ -1935,9 +2011,11 @@ static void dlm_finish_local_lockres_rec if (res->owner == dead_node) { list_del_init(&res->recovering); spin_lock(&res->spinlock); + /* new_master has our reference from + * the lock state sent during recovery */ dlm_change_lockres_owner(dlm, res, new_master); res->state &= ~DLM_LOCK_RES_RECOVERING; - if (!__dlm_lockres_unused(res)) + if (__dlm_lockres_has_locks(res)) __dlm_dirty_lockres(dlm, res); spin_unlock(&res->spinlock); wake_up(&res->wq); @@ -1977,9 +2055,11 @@ static void dlm_finish_local_lockres_rec dlm_lockres_put(res); } spin_lock(&res->spinlock); + /* new_master has our reference from + * the lock state sent during recovery */ dlm_change_lockres_owner(dlm, res, new_master); res->state &= ~DLM_LOCK_RES_RECOVERING; - if (!__dlm_lockres_unused(res)) + if (__dlm_lockres_has_locks(res)) __dlm_dirty_lockres(dlm, res); spin_unlock(&res->spinlock); wake_up(&res->wq); @@ -2048,6 +2128,7 @@ static void dlm_free_dead_locks(struct d { struct list_head *iter, *tmpiter; struct dlm_lock *lock; + unsigned int freed = 0; /* this node is the lockres master: * 1) remove any stale locks for the dead node @@ -2062,6 +2143,7 @@ static void dlm_free_dead_locks(struct d if (lock->ml.node == dead_node) { list_del_init(&lock->list); dlm_lock_put(lock); + freed++; } } list_for_each_safe(iter, tmpiter, &res->converting) { @@ -2069,6 +2151,7 @@ static void dlm_free_dead_locks(struct d if (lock->ml.node == dead_node) { list_del_init(&lock->list); dlm_lock_put(lock); + freed++; } } list_for_each_safe(iter, tmpiter, &res->blocked) { @@ -2076,9 +2159,23 @@ static void dlm_free_dead_locks(struct d if (lock->ml.node == dead_node) { list_del_init(&lock->list); dlm_lock_put(lock); + freed++; } } + if (freed) { + mlog(0, "%s:%.*s: freed %u locks for dead node %u, " + "dropping ref from lockres\n", dlm->name, + res->lockname.len, res->lockname.name, freed, dead_node); + BUG_ON(!test_bit(dead_node, res->refmap)); + dlm_lockres_clear_refmap_bit(dead_node, res); + } else if (test_bit(dead_node, res->refmap)) { + mlog(0, "%s:%.*s: dead node %u had a ref, but had " + "no locks and had not purged before dying\n", dlm->name, + res->lockname.len, res->lockname.name, dead_node); + dlm_lockres_clear_refmap_bit(dead_node, res); + } + /* do not kick thread yet */ __dlm_dirty_lockres(dlm, res); } @@ -2141,9 +2238,21 @@ static void dlm_do_local_recovery_cleanu spin_lock(&res->spinlock); /* zero the lvb if necessary */ dlm_revalidate_lvb(dlm, res, dead_node); - if (res->owner == dead_node) + if (res->owner == dead_node) { + if (res->state & DLM_LOCK_RES_DROPPING_REF) + mlog(0, "%s:%.*s: owned by " + "dead node %u, this node was " + "dropping its ref when it died. " + "continue, dropping the flag.\n", + dlm->name, res->lockname.len, + res->lockname.name, dead_node); + + /* the wake_up for this will happen when the + * RECOVERING flag is dropped later */ + res->state &= ~DLM_LOCK_RES_DROPPING_REF; + dlm_move_lockres_to_recovery_list(dlm, res); - else if (res->owner == dlm->node_num) { + } else if (res->owner == dlm->node_num) { dlm_free_dead_locks(dlm, res, dead_node); __dlm_lockres_calc_usage(dlm, res); } diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c index 0c822f3..620eb82 100644 --- a/fs/ocfs2/dlm/dlmthread.c +++ b/fs/ocfs2/dlm/dlmthread.c @@ -54,9 +54,6 @@ #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_ #include "cluster/masklog.h" static int dlm_thread(void *data); -static void dlm_purge_lockres_now(struct dlm_ctxt *dlm, - struct dlm_lock_resource *lockres); - static void dlm_flush_asts(struct dlm_ctxt *dlm); #define dlm_lock_is_remote(dlm, lock) ((lock)->ml.node != (dlm)->node_num) @@ -82,14 +79,33 @@ repeat: current->state = TASK_RUNNING; } - -int __dlm_lockres_unused(struct dlm_lock_resource *res) +int __dlm_lockres_has_locks(struct dlm_lock_resource *res) { if (list_empty(&res->granted) && list_empty(&res->converting) && - list_empty(&res->blocked) && - list_empty(&res->dirty)) - return 1; + list_empty(&res->blocked)) + return 0; + return 1; +} + +/* "unused": the lockres has no locks, is not on the dirty list, + * has no inflight locks (in the gap between mastery and acquiring + * the first lock), and has no bits in its refmap. + * truly ready to be freed. */ +int __dlm_lockres_unused(struct dlm_lock_resource *res) +{ + if (!__dlm_lockres_has_locks(res) && + list_empty(&res->dirty)) { + /* try not to scan the bitmap unless the first two + * conditions are already true */ + int bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); + if (bit >= O2NM_MAX_NODES) { + /* since the bit for dlm->node_num is not + * set, inflight_locks better be zero */ + BUG_ON(res->inflight_locks != 0); + return 1; + } + } return 0; } @@ -106,46 +122,21 @@ void __dlm_lockres_calc_usage(struct dlm assert_spin_locked(&res->spinlock); if (__dlm_lockres_unused(res)){ - /* For now, just keep any resource we master */ - if (res->owner == dlm->node_num) - { - if (!list_empty(&res->purge)) { - mlog(0, "we master %s:%.*s, but it is on " - "the purge list. Removing\n", - dlm->name, res->lockname.len, - res->lockname.name); - list_del_init(&res->purge); - dlm->purge_count--; - } - return; - } - if (list_empty(&res->purge)) { - mlog(0, "putting lockres %.*s from purge list\n", - res->lockname.len, res->lockname.name); + mlog(0, "putting lockres %.*s:%p onto purge list\n", + res->lockname.len, res->lockname.name, res); res->last_used = jiffies; + dlm_lockres_get(res); list_add_tail(&res->purge, &dlm->purge_list); dlm->purge_count++; - - /* if this node is not the owner, there is - * no way to keep track of who the owner could be. - * unhash it to avoid serious problems. */ - if (res->owner != dlm->node_num) { - mlog(0, "%s:%.*s: doing immediate " - "purge of lockres owned by %u\n", - dlm->name, res->lockname.len, - res->lockname.name, res->owner); - - dlm_purge_lockres_now(dlm, res); - } } } else if (!list_empty(&res->purge)) { - mlog(0, "removing lockres %.*s from purge list, " - "owner=%u\n", res->lockname.len, res->lockname.name, - res->owner); + mlog(0, "removing lockres %.*s:%p from purge list, owner=%u\n", + res->lockname.len, res->lockname.name, res, res->owner); list_del_init(&res->purge); + dlm_lockres_put(res); dlm->purge_count--; } } @@ -163,68 +154,60 @@ void dlm_lockres_calc_usage(struct dlm_c spin_unlock(&dlm->spinlock); } -/* TODO: Eventual API: Called with the dlm spinlock held, may drop it - * to do migration, but will re-acquire before exit. */ -void dlm_purge_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *lockres) +int dlm_purge_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) { int master; - int ret; - - spin_lock(&lockres->spinlock); - master = lockres->owner == dlm->node_num; - spin_unlock(&lockres->spinlock); - - mlog(0, "purging lockres %.*s, master = %d\n", lockres->lockname.len, - lockres->lockname.name, master); + int ret = 0; - /* Non master is the easy case -- no migration required, just - * quit. */ + spin_lock(&res->spinlock); + if (!__dlm_lockres_unused(res)) { + spin_unlock(&res->spinlock); + mlog(0, "%s:%.*s: tried to purge but not unused\n", + dlm->name, res->lockname.len, res->lockname.name); + return -ENOTEMPTY; + } + master = (res->owner == dlm->node_num); if (!master) - goto finish; - - /* Wheee! Migrate lockres here! */ - spin_unlock(&dlm->spinlock); -again: + res->state |= DLM_LOCK_RES_DROPPING_REF; + spin_unlock(&res->spinlock); - ret = dlm_migrate_lockres(dlm, lockres, O2NM_MAX_NODES); - if (ret == -ENOTEMPTY) { - mlog(ML_ERROR, "lockres %.*s still has local locks!\n", - lockres->lockname.len, lockres->lockname.name); + mlog(0, "purging lockres %.*s, master = %d\n", res->lockname.len, + res->lockname.name, master); - BUG(); - } else if (ret < 0) { - mlog(ML_NOTICE, "lockres %.*s: migrate failed, retrying\n", - lockres->lockname.len, lockres->lockname.name); - msleep(100); - goto again; + if (!master) { + /* drop spinlock to do messaging, retake below */ + spin_unlock(&dlm->spinlock); + /* clear our bit from the master's refmap, ignore errors */ + ret = dlm_drop_lockres_ref(dlm, res); + if (ret < 0) { + mlog_errno(ret); + if (!dlm_is_host_down(ret)) + BUG(); + } + mlog(0, "%s:%.*s: dlm_deref_lockres returned %d\n", + dlm->name, res->lockname.len, res->lockname.name, ret); + spin_lock(&dlm->spinlock); } - spin_lock(&dlm->spinlock); - -finish: - if (!list_empty(&lockres->purge)) { - list_del_init(&lockres->purge); + if (!list_empty(&res->purge)) { + mlog(0, "removing lockres %.*s:%p from purgelist, " + "master = %d\n", res->lockname.len, res->lockname.name, + res, master); + list_del_init(&res->purge); + dlm_lockres_put(res); dlm->purge_count--; } - __dlm_unhash_lockres(lockres); -} - -/* make an unused lockres go away immediately. - * as soon as the dlm spinlock is dropped, this lockres - * will not be found. kfree still happens on last put. */ -static void dlm_purge_lockres_now(struct dlm_ctxt *dlm, - struct dlm_lock_resource *lockres) -{ - assert_spin_locked(&dlm->spinlock); - assert_spin_locked(&lockres->spinlock); - - BUG_ON(!__dlm_lockres_unused(lockres)); + __dlm_unhash_lockres(res); - if (!list_empty(&lockres->purge)) { - list_del_init(&lockres->purge); - dlm->purge_count--; + /* lockres is not in the hash now. drop the flag and wake up + * any processes waiting in dlm_get_lock_resource. */ + if (!master) { + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_DROPPING_REF; + spin_unlock(&res->spinlock); + wake_up(&res->wq); } - __dlm_unhash_lockres(lockres); + return 0; } static void dlm_run_purge_list(struct dlm_ctxt *dlm, @@ -268,13 +251,17 @@ static void dlm_run_purge_list(struct dl break; } + mlog(0, "removing lockres %.*s:%p from purgelist\n", + lockres->lockname.len, lockres->lockname.name, lockres); list_del_init(&lockres->purge); + dlm_lockres_put(lockres); dlm->purge_count--; /* This may drop and reacquire the dlm spinlock if it * has to do migration. */ mlog(0, "calling dlm_purge_lockres!\n"); - dlm_purge_lockres(dlm, lockres); + if (dlm_purge_lockres(dlm, lockres)) + BUG(); mlog(0, "DONE calling dlm_purge_lockres!\n"); /* Avoid adding any scheduling latencies */ -- 1.4.2.4