Add API to wait for pending commit callbacks

This adds an API to wait for pending commit callbacks of already-synced
transactions to finish processing.  This is needed by the DMU-OSD in
Lustre during device finalization when some callbacks may still not be
called, this leads to non-zero reference count errors.  See lustre.org
bug 23931.
This commit is contained in:
Ricardo M. Correia 2011-01-21 14:35:41 -08:00 committed by Brian Behlendorf
parent 8d4e8140ef
commit 54a179e7b8
3 changed files with 22 additions and 0 deletions

View File

@ -107,6 +107,12 @@ extern boolean_t txg_stalled(struct dsl_pool *dp);
/* returns TRUE if someone is waiting for the next txg to sync */
extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
/*
* Wait for pending commit callbacks of already-synced transactions to finish
* processing.
*/
extern void txg_wait_callbacks(struct dsl_pool *dp);
/*
* Per-txg object lists.
*/

View File

@ -1813,6 +1813,7 @@ EXPORT_SYMBOL(dmu_objset_destroy);
EXPORT_SYMBOL(dmu_objset_snapshot);
EXPORT_SYMBOL(dmu_objset_stats);
EXPORT_SYMBOL(dmu_objset_fast_stat);
EXPORT_SYMBOL(dmu_objset_spa);
EXPORT_SYMBOL(dmu_objset_space);
EXPORT_SYMBOL(dmu_objset_fsid_guid);
EXPORT_SYMBOL(dmu_objset_find);

View File

@ -350,6 +350,20 @@ txg_dispatch_callbacks(dsl_pool_t *dp, uint64_t txg)
}
}
/*
* Wait for pending commit callbacks of already-synced transactions to finish
* processing.
* Calling this function from within a commit callback will deadlock.
*/
void
txg_wait_callbacks(dsl_pool_t *dp)
{
tx_state_t *tx = &dp->dp_tx;
if (tx->tx_commit_cb_taskq != NULL)
taskq_wait(tx->tx_commit_cb_taskq);
}
static void
txg_sync_thread(dsl_pool_t *dp)
{
@ -735,6 +749,7 @@ EXPORT_SYMBOL(txg_register_callbacks);
EXPORT_SYMBOL(txg_delay);
EXPORT_SYMBOL(txg_wait_synced);
EXPORT_SYMBOL(txg_wait_open);
EXPORT_SYMBOL(txg_wait_callbacks);
EXPORT_SYMBOL(txg_stalled);
EXPORT_SYMBOL(txg_sync_waiting);
#endif