* 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
*
* - 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;
#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)
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
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 */
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
u8 name[O2NM_MAX_NAME_LEN];
};
+#define DLM_MIGRATE_RESPONSE_MASTERY_REF 0x00000001
+
struct dlm_migrate_request
{
u8 master;
__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)
{
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
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,
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,
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);
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);
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)
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;
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);
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;
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)
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)
/* 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);
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,
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);
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,
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,
INIT_LIST_HEAD(&res->purge);
atomic_set(&res->asts_reserved, 0);
res->migration_pending = 0;
+ res->inflight_locks = 0;
kref_init(&res->refs);
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,
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.
unsigned int hash;
int tries = 0;
int bit, wait_on_recovery = 0;
+ int drop_inflight_if_nonlocal = 0;
BUG_ON(!lockid);
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);
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 */
/* 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 */
/* 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
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) {
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);
/* 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);
* 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;
}
(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);
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
/* 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);
*
*/
-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;
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:
}
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);
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);
* 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 {
* 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:
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, "
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)
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))
dlm_change_lockres_owner(dlm, res, mle->master);
}
spin_unlock(&res->spinlock);
+ have_lockres_ref = 1;
}
/* master is known, detach if not already detached.
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;
* 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))
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
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;
{
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);
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
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);
}
}
/* 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);
}
/* 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);
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);
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. */
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 "
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);
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,
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)
/* 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));
"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 */
"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,
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; i<mres->num_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;
/* 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;
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)
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);
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);
{
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
if (lock->ml.node == dead_node) {
list_del_init(&lock->list);
dlm_lock_put(lock);
+ freed++;
}
}
list_for_each_safe(iter, tmpiter, &res->converting) {
if (lock->ml.node == dead_node) {
list_del_init(&lock->list);
dlm_lock_put(lock);
+ freed++;
}
}
list_for_each_safe(iter, tmpiter, &res->blocked) {
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);
}
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);
}
#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)
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;
}
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--;
}
}
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,
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 */
projects / linux-2.6-microblaze.git / commitdiff