#include "dlmapi.h"
#include "dlmcommon.h"
-#include "dlmdebug.h"
#include "dlmdomain.h"
#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER)
wait_queue_head_t wq;
atomic_t woken;
struct kref mle_refs;
+ int inuse;
unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
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 void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data);
static inline int dlm_mle_equal(struct dlm_ctxt *dlm,
struct dlm_master_list_entry *mle,
return 1;
}
-#if 0
-/* Code here is included but defined out as it aids debugging */
+#define dlm_print_nodemap(m) _dlm_print_nodemap(m,#m)
+static void _dlm_print_nodemap(unsigned long *map, const char *mapname)
+{
+ int i;
+ printk("%s=[ ", mapname);
+ for (i=0; i<O2NM_MAX_NODES; i++)
+ if (test_bit(i, map))
+ printk("%d ", i);
+ printk("]");
+}
-void dlm_print_one_mle(struct dlm_master_list_entry *mle)
+static void dlm_print_one_mle(struct dlm_master_list_entry *mle)
{
- int i = 0, refs;
+ int refs;
char *type;
char attached;
u8 master;
unsigned int namelen;
const char *name;
struct kref *k;
+ unsigned long *maybe = mle->maybe_map,
+ *vote = mle->vote_map,
+ *resp = mle->response_map,
+ *node = mle->node_map;
k = &mle->mle_refs;
if (mle->type == DLM_MLE_BLOCK)
name = mle->u.res->lockname.name;
}
- mlog(ML_NOTICE, " #%3d: %3s %3d %3u %3u %c (%d)%.*s\n",
- i, type, refs, master, mle->new_master, attached,
- namelen, namelen, name);
+ mlog(ML_NOTICE, "%.*s: %3s refs=%3d mas=%3u new=%3u evt=%c inuse=%d ",
+ namelen, name, type, refs, master, mle->new_master, attached,
+ mle->inuse);
+ dlm_print_nodemap(maybe);
+ printk(", ");
+ dlm_print_nodemap(vote);
+ printk(", ");
+ dlm_print_nodemap(resp);
+ printk(", ");
+ dlm_print_nodemap(node);
+ printk(", ");
+ printk("\n");
}
+#if 0
+/* Code here is included but defined out as it aids debugging */
+
static void dlm_dump_mles(struct dlm_ctxt *dlm)
{
struct dlm_master_list_entry *mle;
- struct list_head *iter;
mlog(ML_NOTICE, "dumping all mles for domain %s:\n", dlm->name);
- mlog(ML_NOTICE, " ####: type refs owner new events? lockname nodemap votemap respmap maybemap\n");
spin_lock(&dlm->master_lock);
- list_for_each(iter, &dlm->master_list) {
- mle = list_entry(iter, struct dlm_master_list_entry, list);
+ list_for_each_entry(mle, &dlm->master_list, list)
dlm_print_one_mle(mle);
- }
spin_unlock(&dlm->master_lock);
}
int dlm_dump_all_mles(const char __user *data, unsigned int len)
{
- struct list_head *iter;
struct dlm_ctxt *dlm;
spin_lock(&dlm_domain_lock);
- list_for_each(iter, &dlm_domains) {
- dlm = list_entry (iter, struct dlm_ctxt, list);
+ list_for_each_entry(dlm, &dlm_domains, list) {
mlog(ML_NOTICE, "found dlm: %p, name=%s\n", dlm, dlm->name);
dlm_dump_mles(dlm);
}
#endif /* 0 */
-static kmem_cache_t *dlm_mle_cache = NULL;
+static struct kmem_cache *dlm_mle_cache = NULL;
static void dlm_mle_release(struct kref *kref);
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,
spin_unlock(&dlm->spinlock);
}
+static void dlm_get_mle_inuse(struct dlm_master_list_entry *mle)
+{
+ struct dlm_ctxt *dlm;
+ dlm = mle->dlm;
+
+ assert_spin_locked(&dlm->spinlock);
+ assert_spin_locked(&dlm->master_lock);
+ mle->inuse++;
+ kref_get(&mle->mle_refs);
+}
+
+static void dlm_put_mle_inuse(struct dlm_master_list_entry *mle)
+{
+ struct dlm_ctxt *dlm;
+ dlm = mle->dlm;
+
+ spin_lock(&dlm->spinlock);
+ spin_lock(&dlm->master_lock);
+ mle->inuse--;
+ __dlm_put_mle(mle);
+ spin_unlock(&dlm->master_lock);
+ spin_unlock(&dlm->spinlock);
+
+}
+
/* remove from list and free */
static void __dlm_put_mle(struct dlm_master_list_entry *mle)
{
assert_spin_locked(&dlm->spinlock);
assert_spin_locked(&dlm->master_lock);
- BUG_ON(!atomic_read(&mle->mle_refs.refcount));
-
- kref_put(&mle->mle_refs, dlm_mle_release);
+ if (!atomic_read(&mle->mle_refs.refcount)) {
+ /* this may or may not crash, but who cares.
+ * it's a BUG. */
+ mlog(ML_ERROR, "bad mle: %p\n", mle);
+ dlm_print_one_mle(mle);
+ BUG();
+ } else
+ kref_put(&mle->mle_refs, dlm_mle_release);
}
memset(mle->response_map, 0, sizeof(mle->response_map));
mle->master = O2NM_MAX_NODES;
mle->new_master = O2NM_MAX_NODES;
+ mle->inuse = 0;
if (mle->type == DLM_MLE_MASTER) {
BUG_ON(!res);
char *name, unsigned int namelen)
{
struct dlm_master_list_entry *tmpmle;
- struct list_head *iter;
assert_spin_locked(&dlm->master_lock);
- list_for_each(iter, &dlm->master_list) {
- tmpmle = list_entry(iter, struct dlm_master_list_entry, list);
+ list_for_each_entry(tmpmle, &dlm->master_list, list) {
if (!dlm_mle_equal(dlm, tmpmle, name, namelen))
continue;
dlm_get_mle(tmpmle);
void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up)
{
struct dlm_master_list_entry *mle;
- struct list_head *iter;
assert_spin_locked(&dlm->spinlock);
- list_for_each(iter, &dlm->mle_hb_events) {
- mle = list_entry(iter, struct dlm_master_list_entry,
- hb_events);
+ list_for_each_entry(mle, &dlm->mle_hb_events, hb_events) {
if (node_up)
dlm_mle_node_up(dlm, mle, NULL, idx);
else
dlm_mle_cache = kmem_cache_create("dlm_mle_cache",
sizeof(struct dlm_master_list_entry),
0, SLAB_HWCACHE_ALIGN,
- NULL, NULL);
+ NULL);
if (dlm_mle_cache == NULL)
return -ENOMEM;
return 0;
mlog(0, "destroying lockres %.*s\n", res->lockname.len,
res->lockname.name);
+ if (!hlist_unhashed(&res->hash_node) ||
+ !list_empty(&res->granted) ||
+ !list_empty(&res->converting) ||
+ !list_empty(&res->blocked) ||
+ !list_empty(&res->dirty) ||
+ !list_empty(&res->recovering) ||
+ !list_empty(&res->purge)) {
+ mlog(ML_ERROR,
+ "Going to BUG for resource %.*s."
+ " We're on a list! [%c%c%c%c%c%c%c]\n",
+ res->lockname.len, res->lockname.name,
+ !hlist_unhashed(&res->hash_node) ? 'H' : ' ',
+ !list_empty(&res->granted) ? 'G' : ' ',
+ !list_empty(&res->converting) ? 'C' : ' ',
+ !list_empty(&res->blocked) ? 'B' : ' ',
+ !list_empty(&res->dirty) ? 'D' : ' ',
+ !list_empty(&res->recovering) ? 'R' : ' ',
+ !list_empty(&res->purge) ? 'P' : ' ');
+
+ dlm_print_one_lock_resource(res);
+ }
+
/* By the time we're ready to blow this guy away, we shouldn't
* be on any lists. */
BUG_ON(!hlist_unhashed(&res->hash_node));
kfree(res);
}
-void dlm_lockres_get(struct dlm_lock_resource *res)
-{
- kref_get(&res->refs);
-}
-
void dlm_lockres_put(struct dlm_lock_resource *res)
{
kref_put(&res->refs, dlm_lockres_release);
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,
{
struct dlm_lock_resource *res;
- res = kmalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL);
+ res = kmalloc(sizeof(struct dlm_lock_resource), GFP_NOFS);
if (!res)
return NULL;
- res->lockname.name = kmalloc(namelen, GFP_KERNEL);
+ res->lockname.name = kmalloc(namelen, GFP_NOFS);
if (!res->lockname.name) {
kfree(res);
return NULL;
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.
*/
struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
const char *lockid,
+ int namelen,
int flags)
{
struct dlm_lock_resource *tmpres=NULL, *res=NULL;
int blocked = 0;
int ret, nodenum;
struct dlm_node_iter iter;
- unsigned int namelen, hash;
+ unsigned int hash;
int tries = 0;
int bit, wait_on_recovery = 0;
+ int drop_inflight_if_nonlocal = 0;
BUG_ON(!lockid);
- namelen = strlen(lockid);
hash = dlm_lockid_hash(lockid, namelen);
mlog(0, "get lockres %s (len %d)\n", lockid, namelen);
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);
mlog(0, "allocating a new resource\n");
/* nothing found and we need to allocate one. */
alloc_mle = (struct dlm_master_list_entry *)
- kmem_cache_alloc(dlm_mle_cache, GFP_KERNEL);
+ kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
if (!alloc_mle)
goto leave;
res = dlm_new_lockres(dlm, lockid, namelen);
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 */
* but they might own this lockres. wait on them. */
bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
if (bit < O2NM_MAX_NODES) {
- mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to"
+ mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to "
"recover before lock mastery can begin\n",
dlm->name, namelen, (char *)lockid, bit);
wait_on_recovery = 1;
/* 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
* need an extra one to keep from a bad ptr deref. */
- dlm_get_mle(mle);
+ dlm_get_mle_inuse(mle);
spin_unlock(&dlm->master_lock);
spin_unlock(&dlm->spinlock);
+redo_request:
while (wait_on_recovery) {
/* any cluster changes that occurred after dropping the
* dlm spinlock would be detectable be a change on the mle,
}
dlm_kick_recovery_thread(dlm);
- msleep(100);
+ msleep(1000);
dlm_wait_for_recovery(dlm);
spin_lock(&dlm->spinlock);
bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
if (bit < O2NM_MAX_NODES) {
- mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to"
+ mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to "
"recover before lock mastery can begin\n",
dlm->name, namelen, (char *)lockid, bit);
wait_on_recovery = 1;
} else
wait_on_recovery = 0;
spin_unlock(&dlm->spinlock);
+
+ if (wait_on_recovery)
+ dlm_wait_for_node_recovery(dlm, bit, 10000);
}
/* must wait for lock to be mastered elsewhere */
if (blocked)
goto wait;
-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) {
/* keep going until the response map includes all nodes */
ret = dlm_wait_for_lock_mastery(dlm, res, mle, &blocked);
if (ret < 0) {
+ wait_on_recovery = 1;
mlog(0, "%s:%.*s: node map changed, redo the "
"master request now, blocked=%d\n",
dlm->name, res->lockname.len,
dlm->name, res->lockname.len,
res->lockname.name, blocked);
dlm_print_one_lock_resource(res);
- /* dlm_print_one_mle(mle); */
+ dlm_print_one_mle(mle);
tries = 0;
}
goto redo_request;
dlm_mle_detach_hb_events(dlm, mle);
dlm_put_mle(mle);
/* put the extra ref */
- dlm_put_mle(mle);
+ dlm_put_mle_inuse(mle);
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);
spin_unlock(&res->spinlock);
/* this will cause the master to re-assert across
* the whole cluster, freeing up mles */
- ret = dlm_do_master_request(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);
- msleep(500);
- goto recheck;
+ if (res->owner != dlm->node_num) {
+ 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);
+ msleep(500);
+ goto recheck;
+ }
}
ret = 0;
goto leave;
"rechecking now\n", dlm->name, res->lockname.len,
res->lockname.name);
goto recheck;
+ } else {
+ if (!voting_done) {
+ mlog(0, "map not changed and voting not done "
+ "for %s:%.*s\n", dlm->name, res->lockname.len,
+ res->lockname.name);
+ }
}
if (m != O2NM_MAX_NODES) {
* 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);
set_bit(node, mle->vote_map);
} else {
mlog(ML_ERROR, "node down! %d\n", node);
-
- /* if the node wasn't involved in mastery skip it,
- * but clear it out from the maps so that it will
- * not affect mastery of this lockres */
- clear_bit(node, mle->response_map);
- clear_bit(node, mle->vote_map);
- if (!test_bit(node, mle->maybe_map))
- goto next;
-
- /* if we're already blocked on lock mastery, and the
- * dead node wasn't the expected master, or there is
- * another node in the maybe_map, keep waiting */
if (blocked) {
int lowest = find_next_bit(mle->maybe_map,
O2NM_MAX_NODES, 0);
/* act like it was never there */
clear_bit(node, mle->maybe_map);
- if (node != lowest)
- goto next;
-
- mlog(ML_ERROR, "expected master %u died while "
- "this node was blocked waiting on it!\n",
- node);
- lowest = find_next_bit(mle->maybe_map,
- O2NM_MAX_NODES,
- lowest+1);
- if (lowest < O2NM_MAX_NODES) {
- mlog(0, "still blocked. waiting "
- "on %u now\n", lowest);
- goto next;
+ if (node == lowest) {
+ mlog(0, "expected master %u died"
+ " while this node was blocked "
+ "waiting on it!\n", node);
+ lowest = find_next_bit(mle->maybe_map,
+ O2NM_MAX_NODES,
+ lowest+1);
+ if (lowest < O2NM_MAX_NODES) {
+ mlog(0, "%s:%.*s:still "
+ "blocked. waiting on %u "
+ "now\n", dlm->name,
+ res->lockname.len,
+ res->lockname.name,
+ lowest);
+ } else {
+ /* mle is an MLE_BLOCK, but
+ * there is now nothing left to
+ * block on. we need to return
+ * all the way back out and try
+ * again with an MLE_MASTER.
+ * dlm_do_local_recovery_cleanup
+ * has already run, so the mle
+ * refcount is ok */
+ mlog(0, "%s:%.*s: no "
+ "longer blocking. try to "
+ "master this here\n",
+ dlm->name,
+ res->lockname.len,
+ res->lockname.name);
+ mle->type = DLM_MLE_MASTER;
+ mle->u.res = res;
+ }
}
-
- /* mle is an MLE_BLOCK, but there is now
- * nothing left to block on. we need to return
- * all the way back out and try again with
- * an MLE_MASTER. dlm_do_local_recovery_cleanup
- * has already run, so the mle refcount is ok */
- mlog(0, "no longer blocking. we can "
- "try to master this here\n");
- mle->type = DLM_MLE_MASTER;
- memset(mle->maybe_map, 0,
- sizeof(mle->maybe_map));
- memset(mle->response_map, 0,
- sizeof(mle->maybe_map));
- memcpy(mle->vote_map, mle->node_map,
- sizeof(mle->node_map));
- mle->u.res = res;
- set_bit(dlm->node_num, mle->maybe_map);
-
- ret = -EAGAIN;
- goto next;
}
- clear_bit(node, mle->maybe_map);
- if (node > dlm->node_num)
- goto next;
-
- mlog(0, "dead node in map!\n");
- /* yuck. go back and re-contact all nodes
- * in the vote_map, removing this node. */
- memset(mle->response_map, 0,
- sizeof(mle->response_map));
+ /* now blank out everything, as if we had never
+ * contacted anyone */
+ memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
+ memset(mle->response_map, 0, sizeof(mle->response_map));
+ /* reset the vote_map to the current node_map */
+ memcpy(mle->vote_map, mle->node_map,
+ sizeof(mle->node_map));
+ /* put myself into the maybe map */
+ if (mle->type != DLM_MLE_BLOCK)
+ set_bit(dlm->node_num, mle->maybe_map);
}
ret = -EAGAIN;
-next:
node = dlm_bitmap_diff_iter_next(&bdi, &sc);
}
return ret;
*
*/
-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 possible, TRIM THIS DOWN!!!
*/
-int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data)
+int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
+ void **ret_data)
{
u8 response = DLM_MASTER_RESP_MAYBE;
struct dlm_ctxt *dlm = data;
/* take care of the easy cases up front */
spin_lock(&res->spinlock);
- if (res->state & DLM_LOCK_RES_RECOVERING) {
+ if (res->state & (DLM_LOCK_RES_RECOVERING|
+ DLM_LOCK_RES_MIGRATING)) {
spin_unlock(&res->spinlock);
mlog(0, "returning DLM_MASTER_RESP_ERROR since res is "
- "being recovered\n");
+ "being recovered/migrated\n");
response = DLM_MASTER_RESP_ERROR;
if (mle)
kmem_cache_free(dlm_mle_cache, mle);
}
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 {
spin_unlock(&dlm->spinlock);
mle = (struct dlm_master_list_entry *)
- kmem_cache_alloc(dlm_mle_cache, GFP_KERNEL);
+ kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
if (!mle) {
response = DLM_MASTER_RESP_ERROR;
mlog_errno(-ENOMEM);
goto send_response;
}
- spin_lock(&dlm->spinlock);
- dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL,
- name, namelen);
- spin_unlock(&dlm->spinlock);
goto way_up_top;
}
// mlog(0, "this is second time thru, already allocated, "
// "add the block.\n");
+ dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, name, namelen);
set_bit(request->node_idx, mle->maybe_map);
list_add(&mle->list, &dlm->master_list);
response = DLM_MASTER_RESP_NO;
* 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)
+static 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);
+
+ spin_lock(&res->spinlock);
+ res->state |= DLM_LOCK_RES_SETREF_INPROG;
+ spin_unlock(&res->spinlock);
+
again:
reassert = 0;
dlm_node_iter_init(nodemap, &iter);
while ((to = dlm_node_iter_next(&iter)) >= 0) {
int r = 0;
+ struct dlm_master_list_entry *mle = NULL;
+
mlog(0, "sending assert master to %d (%.*s)\n", to,
namelen, lockname);
memset(&assert, 0, sizeof(assert));
tmpret = o2net_send_message(DLM_ASSERT_MASTER_MSG, dlm->key,
&assert, sizeof(assert), to, &r);
if (tmpret < 0) {
- mlog(ML_ERROR, "assert_master returned %d!\n", tmpret);
+ mlog(0, "assert_master returned %d!\n", tmpret);
if (!dlm_is_host_down(tmpret)) {
- mlog(ML_ERROR, "unhandled error!\n");
+ mlog(ML_ERROR, "unhandled error=%d!\n", tmpret);
BUG();
}
/* a node died. finish out the rest of the nodes. */
- mlog(ML_ERROR, "link to %d went down!\n", to);
+ 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, "
"got %d.\n", namelen, lockname, to, r);
- dlm_dump_lock_resources(dlm);
+ spin_lock(&dlm->spinlock);
+ spin_lock(&dlm->master_lock);
+ if (dlm_find_mle(dlm, &mle, (char *)lockname,
+ namelen)) {
+ dlm_print_one_mle(mle);
+ __dlm_put_mle(mle);
+ }
+ 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)
goto again;
+ spin_lock(&res->spinlock);
+ res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
+ spin_unlock(&res->spinlock);
+ wake_up(&res->wq);
+
return ret;
}
*
* if possible, TRIM THIS DOWN!!!
*/
-int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data)
+int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
+ void **ret_data)
{
struct dlm_ctxt *dlm = data;
struct dlm_master_list_entry *mle = NULL;
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))
if (bit >= O2NM_MAX_NODES) {
/* not necessarily an error, though less likely.
* could be master just re-asserting. */
- mlog(ML_ERROR, "no bits set in the maybe_map, but %u "
+ mlog(0, "no bits set in the maybe_map, but %u "
"is asserting! (%.*s)\n", assert->node_idx,
namelen, name);
} else if (bit != assert->node_idx) {
* number winning the mastery will respond
* YES to mastery requests, but this node
* had no way of knowing. let it pass. */
- mlog(ML_ERROR, "%u is the lowest node, "
+ mlog(0, "%u is the lowest node, "
"%u is asserting. (%.*s) %u must "
"have begun after %u won.\n", bit,
assert->node_idx, namelen, name, bit,
assert->node_idx);
}
}
+ if (mle->type == DLM_MLE_MIGRATION) {
+ if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) {
+ mlog(0, "%s:%.*s: got cleanup assert"
+ " from %u for migration\n",
+ dlm->name, namelen, name,
+ assert->node_idx);
+ } else if (!(flags & DLM_ASSERT_MASTER_FINISH_MIGRATION)) {
+ mlog(0, "%s:%.*s: got unrelated assert"
+ " from %u for migration, ignoring\n",
+ dlm->name, namelen, name,
+ assert->node_idx);
+ __dlm_put_mle(mle);
+ spin_unlock(&dlm->master_lock);
+ spin_unlock(&dlm->spinlock);
+ goto done;
+ }
+ }
}
spin_unlock(&dlm->master_lock);
goto kill;
}
if (!mle) {
- if (res->owner != assert->node_idx) {
+ if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN &&
+ res->owner != assert->node_idx) {
mlog(ML_ERROR, "assert_master from "
"%u, but current owner is "
"%u! (%.*s)\n",
if (mle) {
int extra_ref = 0;
int nn = -1;
+ int rr, err = 0;
spin_lock(&mle->spinlock);
if (mle->type == DLM_MLE_BLOCK || mle->type == DLM_MLE_MIGRATION)
wake_up(&mle->wq);
spin_unlock(&mle->spinlock);
- if (mle->type == DLM_MLE_MIGRATION && res) {
- mlog(0, "finishing off migration of lockres %.*s, "
- "from %u to %u\n",
- res->lockname.len, res->lockname.name,
- dlm->node_num, mle->new_master);
+ if (res) {
+ int wake = 0;
spin_lock(&res->spinlock);
- res->state &= ~DLM_LOCK_RES_MIGRATING;
- dlm_change_lockres_owner(dlm, res, mle->new_master);
- BUG_ON(res->state & DLM_LOCK_RES_DIRTY);
+ if (mle->type == DLM_MLE_MIGRATION) {
+ mlog(0, "finishing off migration of lockres %.*s, "
+ "from %u to %u\n",
+ res->lockname.len, res->lockname.name,
+ dlm->node_num, mle->new_master);
+ res->state &= ~DLM_LOCK_RES_MIGRATING;
+ wake = 1;
+ dlm_change_lockres_owner(dlm, res, mle->new_master);
+ BUG_ON(res->state & DLM_LOCK_RES_DIRTY);
+ } else {
+ dlm_change_lockres_owner(dlm, res, mle->master);
+ }
spin_unlock(&res->spinlock);
+ have_lockres_ref = 1;
+ if (wake)
+ wake_up(&res->wq);
}
- /* master is known, detach if not already detached */
- dlm_mle_detach_hb_events(dlm, mle);
- dlm_put_mle(mle);
-
+
+ /* master is known, detach if not already detached.
+ * ensures that only one assert_master call will happen
+ * on this mle. */
+ spin_lock(&dlm->spinlock);
+ spin_lock(&dlm->master_lock);
+
+ rr = atomic_read(&mle->mle_refs.refcount);
+ if (mle->inuse > 0) {
+ if (extra_ref && rr < 3)
+ err = 1;
+ else if (!extra_ref && rr < 2)
+ err = 1;
+ } else {
+ if (extra_ref && rr < 2)
+ err = 1;
+ else if (!extra_ref && rr < 1)
+ err = 1;
+ }
+ if (err) {
+ mlog(ML_ERROR, "%s:%.*s: got assert master from %u "
+ "that will mess up this node, refs=%d, extra=%d, "
+ "inuse=%d\n", dlm->name, namelen, name,
+ assert->node_idx, rr, extra_ref, mle->inuse);
+ dlm_print_one_mle(mle);
+ }
+ list_del_init(&mle->list);
+ __dlm_mle_detach_hb_events(dlm, mle);
+ __dlm_put_mle(mle);
if (extra_ref) {
/* the assert master message now balances the extra
* ref given by the master / migration request message.
* if this is the last put, it will be removed
* from the list. */
- dlm_put_mle(mle);
+ __dlm_put_mle(mle);
+ }
+ spin_unlock(&dlm->master_lock);
+ spin_unlock(&dlm->spinlock);
+ } else if (res) {
+ if (res->owner != assert->node_idx) {
+ mlog(0, "assert_master from %u, but current "
+ "owner is %u (%.*s), no mle\n", assert->node_idx,
+ res->owner, namelen, name);
}
}
done:
ret = 0;
- if (res)
- dlm_lockres_put(res);
+ if (res) {
+ spin_lock(&res->spinlock);
+ res->state |= DLM_LOCK_RES_SETREF_INPROG;
+ spin_unlock(&res->spinlock);
+ *ret_data = (void *)res;
+ }
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;
kill:
/* kill the caller! */
- spin_unlock(&res->spinlock);
- spin_unlock(&dlm->spinlock);
- dlm_lockres_put(res);
mlog(ML_ERROR, "Bad message received from another node. Dumping state "
"and killing the other node now! This node is OK and can continue.\n");
- dlm_dump_lock_resources(dlm);
+ __dlm_print_one_lock_resource(res);
+ spin_unlock(&res->spinlock);
+ spin_unlock(&dlm->spinlock);
+ *ret_data = (void *)res;
dlm_put(dlm);
return -EINVAL;
}
+void dlm_assert_master_post_handler(int status, void *data, void *ret_data)
+{
+ struct dlm_lock_resource *res = (struct dlm_lock_resource *)ret_data;
+
+ if (ret_data) {
+ spin_lock(&res->spinlock);
+ res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
+ spin_unlock(&res->spinlock);
+ wake_up(&res->wq);
+ dlm_lockres_put(res);
+ }
+ return;
+}
+
int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
struct dlm_lock_resource *res,
int ignore_higher, u8 request_from, u32 flags)
{
struct dlm_work_item *item;
- item = kcalloc(1, sizeof(*item), GFP_KERNEL);
+ item = kzalloc(sizeof(*item), GFP_NOFS);
if (!item)
return -ENOMEM;
list_add_tail(&item->list, &dlm->work_list);
spin_unlock(&dlm->work_lock);
- schedule_work(&dlm->dispatched_work);
+ queue_work(dlm->dlm_worker, &dlm->dispatched_work);
return 0;
}
}
}
+ /*
+ * If we're migrating this lock to someone else, we are no
+ * longer allowed to assert out own mastery. OTOH, we need to
+ * prevent migration from starting while we're still asserting
+ * our dominance. The reserved ast delays migration.
+ */
+ spin_lock(&res->spinlock);
+ if (res->state & DLM_LOCK_RES_MIGRATING) {
+ mlog(0, "Someone asked us to assert mastery, but we're "
+ "in the middle of migration. Skipping assert, "
+ "the new master will handle that.\n");
+ spin_unlock(&res->spinlock);
+ goto put;
+ } else
+ __dlm_lockres_reserve_ast(res);
+ spin_unlock(&res->spinlock);
+
/* this call now finishes out the nodemap
* 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 */
- mlog_errno(ret);
+ if (!dlm_is_host_down(ret))
+ mlog_errno(ret);
}
+ /* Ok, we've asserted ourselves. Let's let migration start. */
+ dlm_lockres_release_ast(dlm, res);
+
+put:
dlm_lockres_put(res);
mlog(0, "finished with dlm_assert_master_worker\n");
BUG();
/* host is down, so answer for that node would be
* DLM_LOCK_RES_OWNER_UNKNOWN. continue. */
+ ret = 0;
}
if (master != DLM_LOCK_RES_OWNER_UNKNOWN) {
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,
+ void **ret_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;
+ struct dlm_work_item *item;
+ int cleared = 0;
+ int dispatch = 0;
+
+ 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);
+ if (res->state & DLM_LOCK_RES_SETREF_INPROG)
+ dispatch = 1;
+ else {
+ BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
+ if (test_bit(node, res->refmap)) {
+ dlm_lockres_clear_refmap_bit(node, res);
+ cleared = 1;
+ }
+ }
+ spin_unlock(&res->spinlock);
+
+ if (!dispatch) {
+ if (cleared)
+ dlm_lockres_calc_usage(dlm, res);
+ else {
+ mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
+ "but it is already dropped!\n", dlm->name,
+ res->lockname.len, res->lockname.name, node);
+ __dlm_print_one_lock_resource(res);
+ }
+ ret = 0;
+ goto done;
+ }
+
+ item = kzalloc(sizeof(*item), GFP_NOFS);
+ if (!item) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto done;
+ }
+
+ dlm_init_work_item(dlm, item, dlm_deref_lockres_worker, NULL);
+ item->u.dl.deref_res = res;
+ item->u.dl.deref_node = node;
+
+ spin_lock(&dlm->work_lock);
+ list_add_tail(&item->list, &dlm->work_list);
+ spin_unlock(&dlm->work_lock);
+
+ queue_work(dlm->dlm_worker, &dlm->dispatched_work);
+ return 0;
+
+done:
+ if (res)
+ dlm_lockres_put(res);
+ dlm_put(dlm);
+
+ return ret;
+}
+
+static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data)
+{
+ struct dlm_ctxt *dlm;
+ struct dlm_lock_resource *res;
+ u8 node;
+ u8 cleared = 0;
+
+ dlm = item->dlm;
+ res = item->u.dl.deref_res;
+ node = item->u.dl.deref_node;
+
+ spin_lock(&res->spinlock);
+ BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
+ if (test_bit(node, res->refmap)) {
+ __dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG);
+ dlm_lockres_clear_refmap_bit(node, res);
+ cleared = 1;
+ }
+ spin_unlock(&res->spinlock);
+
+ if (cleared) {
+ mlog(0, "%s:%.*s node %u ref dropped in dispatch\n",
+ dlm->name, res->lockname.len, res->lockname.name, node);
+ dlm_lockres_calc_usage(dlm, res);
+ } else {
+ mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
+ "but it is already dropped!\n", dlm->name,
+ res->lockname.len, res->lockname.name, node);
+ __dlm_print_one_lock_resource(res);
+ }
+
+ dlm_lockres_put(res);
+}
+
+/* Checks whether the lockres can be migrated. Returns 0 if yes, < 0
+ * if not. If 0, numlocks is set to the number of locks in the lockres.
+ */
+static int dlm_is_lockres_migrateable(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ int *numlocks)
+{
+ int ret;
+ int i;
+ int count = 0;
+ struct list_head *queue;
+ struct dlm_lock *lock;
+
+ assert_spin_locked(&res->spinlock);
+
+ ret = -EINVAL;
+ if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
+ mlog(0, "cannot migrate lockres with unknown owner!\n");
+ goto leave;
+ }
+
+ if (res->owner != dlm->node_num) {
+ mlog(0, "cannot migrate lockres this node doesn't own!\n");
+ goto leave;
+ }
+
+ ret = 0;
+ queue = &res->granted;
+ for (i = 0; i < 3; i++) {
+ list_for_each_entry(lock, queue, list) {
+ ++count;
+ if (lock->ml.node == dlm->node_num) {
+ mlog(0, "found a lock owned by this node still "
+ "on the %s queue! will not migrate this "
+ "lockres\n", (i == 0 ? "granted" :
+ (i == 1 ? "converting" :
+ "blocked")));
+ ret = -ENOTEMPTY;
+ goto leave;
+ }
+ }
+ queue++;
+ }
+
+ *numlocks = count;
+ mlog(0, "migrateable lockres having %d locks\n", *numlocks);
+
+leave:
+ return ret;
+}
/*
* DLM_MIGRATE_LOCKRES
*/
-int dlm_migrate_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
- u8 target)
+static int dlm_migrate_lockres(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ u8 target)
{
struct dlm_master_list_entry *mle = NULL;
struct dlm_master_list_entry *oldmle = NULL;
struct dlm_migratable_lockres *mres = NULL;
- int ret = -EINVAL;
+ int ret = 0;
const char *name;
unsigned int namelen;
int mle_added = 0;
- struct list_head *queue, *iter;
- int i;
- struct dlm_lock *lock;
- int empty = 1;
+ int numlocks;
+ int wake = 0;
if (!dlm_grab(dlm))
return -EINVAL;
* ensure this lockres is a proper candidate for migration
*/
spin_lock(&res->spinlock);
- if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
- mlog(0, "cannot migrate lockres with unknown owner!\n");
- spin_unlock(&res->spinlock);
- goto leave;
- }
- if (res->owner != dlm->node_num) {
- mlog(0, "cannot migrate lockres this node doesn't own!\n");
+ ret = dlm_is_lockres_migrateable(dlm, res, &numlocks);
+ if (ret < 0) {
spin_unlock(&res->spinlock);
goto leave;
}
- mlog(0, "checking queues...\n");
- queue = &res->granted;
- for (i=0; i<3; i++) {
- list_for_each(iter, queue) {
- lock = list_entry (iter, struct dlm_lock, list);
- empty = 0;
- if (lock->ml.node == dlm->node_num) {
- mlog(0, "found a lock owned by this node "
- "still on the %s queue! will not "
- "migrate this lockres\n",
- i==0 ? "granted" :
- (i==1 ? "converting" : "blocked"));
- spin_unlock(&res->spinlock);
- ret = -ENOTEMPTY;
- goto leave;
- }
- }
- queue++;
- }
- mlog(0, "all locks on this lockres are nonlocal. continuing\n");
spin_unlock(&res->spinlock);
/* no work to do */
- if (empty) {
+ if (numlocks == 0) {
mlog(0, "no locks were found on this lockres! done!\n");
- ret = 0;
goto leave;
}
*/
ret = -ENOMEM;
- mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_KERNEL);
+ mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_NOFS);
if (!mres) {
mlog_errno(ret);
goto leave;
}
mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache,
- GFP_KERNEL);
+ GFP_NOFS);
if (!mle) {
mlog_errno(ret);
goto leave;
res->lockname.name, target);
spin_lock(&res->spinlock);
res->state &= ~DLM_LOCK_RES_MIGRATING;
+ wake = 1;
spin_unlock(&res->spinlock);
ret = -EINVAL;
}
* the lockres
*/
+ /* now that remote nodes are spinning on the MIGRATING flag,
+ * ensure that all assert_master work is flushed. */
+ flush_workqueue(dlm->dlm_worker);
/* get an extra reference on the mle.
* otherwise the assert_master from the new
* take both dlm->spinlock and dlm->master_lock */
spin_lock(&dlm->spinlock);
spin_lock(&dlm->master_lock);
- dlm_get_mle(mle);
+ dlm_get_mle_inuse(mle);
spin_unlock(&dlm->master_lock);
spin_unlock(&dlm->spinlock);
/* migration failed, detach and clean up mle */
dlm_mle_detach_hb_events(dlm, mle);
dlm_put_mle(mle);
- dlm_put_mle(mle);
+ dlm_put_mle_inuse(mle);
+ spin_lock(&res->spinlock);
+ res->state &= ~DLM_LOCK_RES_MIGRATING;
+ wake = 1;
+ spin_unlock(&res->spinlock);
goto leave;
}
res->owner == target)
break;
- mlog(0, "timed out during migration\n");
+ mlog(0, "%s:%.*s: timed out during migration\n",
+ dlm->name, res->lockname.len, res->lockname.name);
/* avoid hang during shutdown when migrating lockres
* to a node which also goes down */
if (dlm_is_node_dead(dlm, target)) {
- mlog(0, "%s:%.*s: expected migration target %u "
- "is no longer up. restarting.\n",
+ mlog(0, "%s:%.*s: expected migration "
+ "target %u is no longer up, restarting\n",
dlm->name, res->lockname.len,
res->lockname.name, target);
- ret = -ERESTARTSYS;
+ ret = -EINVAL;
+ /* migration failed, detach and clean up mle */
+ dlm_mle_detach_hb_events(dlm, mle);
+ dlm_put_mle(mle);
+ dlm_put_mle_inuse(mle);
+ spin_lock(&res->spinlock);
+ res->state &= ~DLM_LOCK_RES_MIGRATING;
+ wake = 1;
+ spin_unlock(&res->spinlock);
+ goto leave;
}
- }
- if (ret == -ERESTARTSYS) {
- /* migration failed, detach and clean up mle */
- dlm_mle_detach_hb_events(dlm, mle);
- dlm_put_mle(mle);
- dlm_put_mle(mle);
- goto leave;
- }
- /* TODO: if node died: stop, clean up, return error */
+ } else
+ mlog(0, "%s:%.*s: caught signal during migration\n",
+ dlm->name, res->lockname.len, res->lockname.name);
}
/* all done, set the owner, clear the flag */
/* master is known, detach if not already detached */
dlm_mle_detach_hb_events(dlm, mle);
- dlm_put_mle(mle);
+ dlm_put_mle_inuse(mle);
ret = 0;
dlm_lockres_calc_usage(dlm, res);
if (ret < 0)
dlm_kick_thread(dlm, res);
+ /* wake up waiters if the MIGRATING flag got set
+ * but migration failed */
+ if (wake)
+ wake_up(&res->wq);
+
/* TODO: cleanup */
if (mres)
free_page((unsigned long)mres);
mlog(0, "returning %d\n", ret);
return ret;
}
-EXPORT_SYMBOL_GPL(dlm_migrate_lockres);
+
+#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;
+ int numlocks;
+
+ spin_lock(&res->spinlock);
+ 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);
+ }
+ spin_unlock(&res->spinlock);
+ goto leave;
+ }
+
+ /* No need to migrate a lockres having no locks */
+ ret = dlm_is_lockres_migrateable(dlm, res, &numlocks);
+ if (ret >= 0 && numlocks == 0) {
+ spin_unlock(&res->spinlock);
+ goto leave;
+ }
+ spin_unlock(&res->spinlock);
+
+ /* 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)
{
return can_proceed;
}
-int dlm_lockres_is_dirty(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
+static int dlm_lockres_is_dirty(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res)
{
int ret;
spin_lock(&res->spinlock);
__dlm_lockres_reserve_ast(res);
spin_unlock(&res->spinlock);
- /* now flush all the pending asts.. hang out for a bit */
+ /* now flush all the pending asts */
dlm_kick_thread(dlm, res);
+ /* before waiting on DIRTY, block processes which may
+ * try to dirty the lockres before MIGRATING is set */
+ spin_lock(&res->spinlock);
+ BUG_ON(res->state & DLM_LOCK_RES_BLOCK_DIRTY);
+ res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
+ spin_unlock(&res->spinlock);
+ /* now wait on any pending asts and the DIRTY state */
wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
dlm_lockres_release_ast(dlm, res);
mlog(0, "trying again...\n");
goto again;
}
+ /* now that we are sure the MIGRATING state is there, drop
+ * the unneded state which blocked threads trying to DIRTY */
+ spin_lock(&res->spinlock);
+ BUG_ON(!(res->state & DLM_LOCK_RES_BLOCK_DIRTY));
+ BUG_ON(!(res->state & DLM_LOCK_RES_MIGRATING));
+ res->state &= ~DLM_LOCK_RES_BLOCK_DIRTY;
+ spin_unlock(&res->spinlock);
/* did the target go down or die? */
spin_lock(&dlm->spinlock);
static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
struct dlm_lock_resource *res)
{
- struct list_head *iter, *iter2;
struct list_head *queue = &res->granted;
- int i;
- struct dlm_lock *lock;
+ int i, bit;
+ struct dlm_lock *lock, *next;
assert_spin_locked(&res->spinlock);
BUG_ON(res->owner == dlm->node_num);
for (i=0; i<3; i++) {
- list_for_each_safe(iter, iter2, queue) {
- lock = list_entry (iter, struct dlm_lock, list);
+ list_for_each_entry_safe(lock, next, queue, list) {
if (lock->ml.node != dlm->node_num) {
mlog(0, "putting lock for node %u\n",
lock->ml.node);
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
{
int i;
struct list_head *queue = &res->granted;
- struct list_head *iter;
struct dlm_lock *lock;
int nodenum;
spin_lock(&res->spinlock);
for (i=0; i<3; i++) {
- list_for_each(iter, queue) {
+ list_for_each_entry(lock, queue, list) {
/* up to the caller to make sure this node
* is alive */
- lock = list_entry (iter, struct dlm_lock, list);
if (lock->ml.node != dlm->node_num) {
spin_unlock(&res->spinlock);
return lock->ml.node;
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);
}
}
* we will have no mle in the list to start with. now we can add an mle for
* the migration and this should be the only one found for those scanning the
* list. */
-int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data)
+int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
+ void **ret_data)
{
struct dlm_ctxt *dlm = data;
struct dlm_lock_resource *res = NULL;
/* preallocate.. if this fails, abort */
mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache,
- GFP_KERNEL);
+ GFP_NOFS);
if (!mle) {
ret = -ENOMEM;
/* remove it from the list so that only one
* mle will be found */
list_del_init(&tmp->list);
+ /* 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);
void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node)
{
- struct list_head *iter, *iter2;
- struct dlm_master_list_entry *mle;
+ struct dlm_master_list_entry *mle, *next;
struct dlm_lock_resource *res;
unsigned int hash;
/* clean the master list */
spin_lock(&dlm->master_lock);
- list_for_each_safe(iter, iter2, &dlm->master_list) {
- mle = list_entry(iter, struct dlm_master_list_entry, list);
-
+ list_for_each_entry_safe(mle, next, &dlm->master_list, list) {
BUG_ON(mle->type != DLM_MLE_BLOCK &&
mle->type != DLM_MLE_MASTER &&
mle->type != DLM_MLE_MIGRATION);
* may result in the mle being unlinked and
* freed, but there may still be a process
* waiting in the dlmlock path which is fine. */
- mlog(ML_ERROR, "node %u was expected master\n",
+ mlog(0, "node %u was expected master\n",
dead_node);
atomic_set(&mle->woken, 1);
spin_unlock(&mle->spinlock);
/* remove from the list early. NOTE: unlinking
* list_head while in list_for_each_safe */
+ __dlm_mle_detach_hb_events(dlm, mle);
spin_lock(&mle->spinlock);
list_del_init(&mle->list);
atomic_set(&mle->woken, 1);
spin_unlock(&mle->spinlock);
wake_up(&mle->wq);
- mlog(0, "node %u died during migration from "
- "%u to %u!\n", dead_node,
+ mlog(0, "%s: node %u died during migration from "
+ "%u to %u!\n", dlm->name, dead_node,
mle->master, mle->new_master);
/* if there is a lockres associated with this
* mle, find it and set its owner to UNKNOWN */
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 "
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff