INIT_LIST_HEAD(&realm->child_item);
INIT_LIST_HEAD(&realm->empty_item);
INIT_LIST_HEAD(&realm->dirty_item);
+ INIT_LIST_HEAD(&realm->rebuild_item);
INIT_LIST_HEAD(&realm->inodes_with_caps);
spin_lock_init(&realm->inodes_with_caps_lock);
__insert_snap_realm(&mdsc->snap_realms, realm);
* build the snap context for a given realm.
*/
static int build_snap_context(struct ceph_snap_realm *realm,
- struct list_head* dirty_realms)
+ struct list_head *realm_queue,
+ struct list_head *dirty_realms)
{
struct ceph_snap_realm *parent = realm->parent;
struct ceph_snap_context *snapc;
*/
if (parent) {
if (!parent->cached_context) {
- err = build_snap_context(parent, dirty_realms);
- if (err)
- goto fail;
+ /* add to the queue head */
+ list_add(&parent->rebuild_item, realm_queue);
+ return 1;
}
num += parent->cached_context->num_snaps;
}
static void rebuild_snap_realms(struct ceph_snap_realm *realm,
struct list_head *dirty_realms)
{
- struct ceph_snap_realm *child;
+ LIST_HEAD(realm_queue);
+ int last = 0;
+ bool skip = false;
- dout("rebuild_snap_realms %llx %p\n", realm->ino, realm);
- build_snap_context(realm, dirty_realms);
+ list_add_tail(&realm->rebuild_item, &realm_queue);
- list_for_each_entry(child, &realm->children, child_item)
- rebuild_snap_realms(child, dirty_realms);
+ while (!list_empty(&realm_queue)) {
+ struct ceph_snap_realm *_realm, *child;
+
+ _realm = list_first_entry(&realm_queue,
+ struct ceph_snap_realm,
+ rebuild_item);
+
+ /*
+ * If the last building failed dues to memory
+ * issue, just empty the realm_queue and return
+ * to avoid infinite loop.
+ */
+ if (last < 0) {
+ list_del_init(&_realm->rebuild_item);
+ continue;
+ }
+
+ last = build_snap_context(_realm, &realm_queue, dirty_realms);
+ dout("rebuild_snap_realms %llx %p, %s\n", _realm->ino, _realm,
+ last > 0 ? "is deferred" : !last ? "succeeded" : "failed");
+
+ /* is any child in the list ? */
+ list_for_each_entry(child, &_realm->children, child_item) {
+ if (!list_empty(&child->rebuild_item)) {
+ skip = true;
+ break;
+ }
+ }
+
+ if (!skip) {
+ list_for_each_entry(child, &_realm->children, child_item)
+ list_add_tail(&child->rebuild_item, &realm_queue);
+ }
+
+ /* last == 1 means need to build parent first */
+ if (last <= 0)
+ list_del_init(&_realm->rebuild_item);
+ }
}
struct ceph_buffer *old_blob = NULL;
int used, dirty;
- capsnap = kzalloc(sizeof(*capsnap), GFP_NOFS);
+ capsnap = kmem_cache_zalloc(ceph_cap_snap_cachep, GFP_NOFS);
if (!capsnap) {
pr_err("ENOMEM allocating ceph_cap_snap on %p\n", inode);
return;
spin_unlock(&ci->i_ceph_lock);
ceph_buffer_put(old_blob);
- kfree(capsnap);
+ if (capsnap)
+ kmem_cache_free(ceph_cap_snap_cachep, capsnap);
ceph_put_snap_context(old_snapc);
}
__le64 *prior_parent_snaps; /* encoded */
struct ceph_snap_realm *realm = NULL;
struct ceph_snap_realm *first_realm = NULL;
- int invalidate = 0;
+ struct ceph_snap_realm *realm_to_rebuild = NULL;
+ int rebuild_snapcs;
int err = -ENOMEM;
LIST_HEAD(dirty_realms);
dout("update_snap_trace deletion=%d\n", deletion);
more:
+ rebuild_snapcs = 0;
ceph_decode_need(&p, e, sizeof(*ri), bad);
ri = p;
p += sizeof(*ri);
err = adjust_snap_realm_parent(mdsc, realm, le64_to_cpu(ri->parent));
if (err < 0)
goto fail;
- invalidate += err;
+ rebuild_snapcs += err;
if (le64_to_cpu(ri->seq) > realm->seq) {
dout("update_snap_trace updating %llx %p %lld -> %lld\n",
if (realm->seq > mdsc->last_snap_seq)
mdsc->last_snap_seq = realm->seq;
- invalidate = 1;
+ rebuild_snapcs = 1;
} else if (!realm->cached_context) {
dout("update_snap_trace %llx %p seq %lld new\n",
realm->ino, realm, realm->seq);
- invalidate = 1;
+ rebuild_snapcs = 1;
} else {
dout("update_snap_trace %llx %p seq %lld unchanged\n",
realm->ino, realm, realm->seq);
}
- dout("done with %llx %p, invalidated=%d, %p %p\n", realm->ino,
- realm, invalidate, p, e);
+ dout("done with %llx %p, rebuild_snapcs=%d, %p %p\n", realm->ino,
+ realm, rebuild_snapcs, p, e);
+
+ /*
+ * this will always track the uppest parent realm from which
+ * we need to rebuild the snapshot contexts _downward_ in
+ * hierarchy.
+ */
+ if (rebuild_snapcs)
+ realm_to_rebuild = realm;
- /* invalidate when we reach the _end_ (root) of the trace */
- if (invalidate && p >= e)
- rebuild_snap_realms(realm, &dirty_realms);
+ /* rebuild_snapcs when we reach the _end_ (root) of the trace */
+ if (realm_to_rebuild && p >= e)
+ rebuild_snap_realms(realm_to_rebuild, &dirty_realms);
if (!first_realm)
first_realm = realm;