/**
* Downgrade an exclusive lock.
*
- * A fast variant of ldlm_lock_convert for convertion of exclusive
- * locks. The convertion is always successful.
+ * A fast variant of ldlm_lock_convert for convertion of exclusive locks. The
+ * convertion may fail if lock was canceled before downgrade, but it doesn't
+ * indicate any problem, because such lock has no reader or writer, and will
+ * be released soon.
* Used by Commit on Sharing (COS) code.
*
* \param lock A lock to convert
*/
void ldlm_lock_downgrade(struct ldlm_lock *lock, enum ldlm_mode new_mode)
{
- ENTRY;
+ ENTRY;
- LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
- LASSERT(new_mode == LCK_COS);
+ LASSERT(new_mode == LCK_COS);
- lock_res_and_lock(lock);
- ldlm_resource_unlink_lock(lock);
- /*
- * Remove the lock from pool as it will be added again in
- * ldlm_grant_lock() called below.
- */
- ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock);
+ lock_res_and_lock(lock);
- lock->l_req_mode = new_mode;
- ldlm_grant_lock(lock, NULL);
- unlock_res_and_lock(lock);
- ldlm_reprocess_all(lock->l_resource);
+ if (!(lock->l_granted_mode & (LCK_PW | LCK_EX))) {
+ unlock_res_and_lock(lock);
- EXIT;
+ LASSERT(lock->l_granted_mode == LCK_MINMODE);
+ LDLM_DEBUG(lock, "lock was canceled before downgrade");
+ RETURN_EXIT;
+ }
+
+ ldlm_resource_unlink_lock(lock);
+ /*
+ * Remove the lock from pool as it will be added again in
+ * ldlm_grant_lock() called below.
+ */
+ ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock);
+ lock->l_req_mode = new_mode;
+ ldlm_grant_lock(lock, NULL);
+
+ unlock_res_and_lock(lock);
+
+ ldlm_reprocess_all(lock->l_resource);
+
+ EXIT;
}
EXPORT_SYMBOL(ldlm_lock_downgrade);
ldlm_lock_downgrade(lock, LCK_COS);
mode = LCK_COS;
}
- ptlrpc_save_lock(req, h, mode, cos,
- convert_lock);
+ if (req->rq_export->exp_disconnected)
+ mdt_fid_unlock(h, mode);
+ else
+ ptlrpc_save_lock(req, h, mode, cos,
+ convert_lock);
} else {
mdt_fid_unlock(h, mode);
}
static void mdt_steal_ack_locks(struct ptlrpc_request *req)
{
struct ptlrpc_service_part *svcpt;
- struct obd_export *exp = req->rq_export;
- struct list_head *tmp;
- struct ptlrpc_reply_state *oldrep;
- int i;
+ struct obd_export *exp = req->rq_export;
+ struct list_head *tmp;
+ struct ptlrpc_reply_state *rs;
+ int i;
/* CAVEAT EMPTOR: spinlock order */
spin_lock(&exp->exp_lock);
list_for_each(tmp, &exp->exp_outstanding_replies) {
- oldrep = list_entry(tmp, struct ptlrpc_reply_state,
+ rs = list_entry(tmp, struct ptlrpc_reply_state,
rs_exp_list);
- if (oldrep->rs_xid != req->rq_xid)
+ if (rs->rs_xid != req->rq_xid)
continue;
- if (oldrep->rs_opc != lustre_msg_get_opc(req->rq_reqmsg))
+ if (rs->rs_opc != lustre_msg_get_opc(req->rq_reqmsg))
CERROR("%s: Resent req xid %llu has mismatched opc: "
"new %d old %d\n", exp->exp_obd->obd_name,
req->rq_xid, lustre_msg_get_opc(req->rq_reqmsg),
- oldrep->rs_opc);
-
- svcpt = oldrep->rs_svcpt;
- spin_lock(&svcpt->scp_rep_lock);
+ rs->rs_opc);
- list_del_init(&oldrep->rs_exp_list);
+ svcpt = rs->rs_svcpt;
CDEBUG(D_HA, "Stealing %d locks from rs %p x%lld.t%lld"
" o%d NID %s\n",
- oldrep->rs_nlocks, oldrep,
- oldrep->rs_xid, oldrep->rs_transno, oldrep->rs_opc,
+ rs->rs_nlocks, rs,
+ rs->rs_xid, rs->rs_transno, rs->rs_opc,
libcfs_nid2str(exp->exp_connection->c_peer.nid));
- for (i = 0; i < oldrep->rs_nlocks; i++)
- ptlrpc_save_lock(req, &oldrep->rs_locks[i],
- oldrep->rs_modes[i], oldrep->rs_no_ack,
- oldrep->rs_convert_lock);
- oldrep->rs_nlocks = 0;
+ spin_lock(&svcpt->scp_rep_lock);
+ list_del_init(&rs->rs_exp_list);
+
+ spin_lock(&rs->rs_lock);
+ for (i = 0; i < rs->rs_nlocks; i++)
+ ptlrpc_save_lock(req, &rs->rs_locks[i],
+ rs->rs_modes[i], rs->rs_no_ack,
+ rs->rs_convert_lock);
+ rs->rs_nlocks = 0;
DEBUG_REQ(D_HA, req, "stole locks for");
- spin_lock(&oldrep->rs_lock);
- ptlrpc_schedule_difficult_reply(oldrep);
- spin_unlock(&oldrep->rs_lock);
+ ptlrpc_schedule_difficult_reply(rs);
+ spin_unlock(&rs->rs_lock);
spin_unlock(&svcpt->scp_rep_lock);
break;
}
spin_unlock(&exp->exp_lock);
+
+ /* if exp_disconnected, decref stolen locks */
+ if (exp->exp_disconnected) {
+ rs = req->rq_reply_state;
+
+ for (i = 0; i < rs->rs_nlocks; i++)
+ ldlm_lock_decref(&rs->rs_locks[i], rs->rs_modes[i]);
+
+ rs->rs_nlocks = 0;
+ }
}
__u64 mdt_req_from_lrd(struct ptlrpc_request *req,
nrs->rs_difficult = 1;
nrs->rs_no_ack = rs->rs_no_ack;
+ nrs->rs_convert_lock = rs->rs_convert_lock;
for (i = 0; i < rs->rs_nlocks; i++) {
nrs->rs_locks[i] = rs->rs_locks[i];
nrs->rs_modes[i] = rs->rs_modes[i];
LASSERT(rs != NULL);
LASSERT(rs->rs_nlocks < RS_MAX_LOCKS);
- if (req->rq_export->exp_disconnected) {
- ldlm_lock_decref(lock, mode);
- } else {
- idx = rs->rs_nlocks++;
- rs->rs_locks[idx] = *lock;
- rs->rs_modes[idx] = mode;
- rs->rs_difficult = 1;
- rs->rs_no_ack = no_ack;
- rs->rs_convert_lock = convert_lock;
- }
+ idx = rs->rs_nlocks++;
+ rs->rs_locks[idx] = *lock;
+ rs->rs_modes[idx] = mode;
+ rs->rs_difficult = 1;
+ rs->rs_no_ack = no_ack;
+ rs->rs_convert_lock = convert_lock;
}
EXPORT_SYMBOL(ptlrpc_save_lock);
if (rs->rs_convert_lock &&
rs->rs_transno > exp->exp_last_committed) {
struct ldlm_lock *lock;
+ struct ldlm_lock *ack_locks[RS_MAX_LOCKS] = { NULL };
spin_lock(&rs->rs_lock);
if (rs->rs_convert_lock &&
rs->rs_transno > exp->exp_last_committed) {
nlocks = rs->rs_nlocks;
- while (nlocks-- > 0)
+ while (nlocks-- > 0) {
+ /*
+ * NB don't assume rs is always handled
+ * by the same service thread (see
+ * ptlrpc_hr_select, so REP-ACK hr may
+ * race with trans commit, while the
+ * latter will release locks, get locks
+ * here early to convert to COS mode
+ * safely.
+ */
+ lock = ldlm_handle2lock(
+ &rs->rs_locks[nlocks]);
+ LASSERT(lock);
+ ack_locks[nlocks] = lock;
rs->rs_modes[nlocks] = LCK_COS;
+ }
nlocks = rs->rs_nlocks;
rs->rs_convert_lock = 0;
/* clear rs_scheduled so that commit callback
spin_unlock(&rs->rs_lock);
while (nlocks-- > 0) {
- lock = ldlm_handle2lock(
- &rs->rs_locks[nlocks]);
- LASSERT(lock != NULL);
+ lock = ack_locks[nlocks];
ldlm_lock_downgrade(lock, LCK_COS);
LDLM_LOCK_PUT(lock);
}
git://git.whamcloud.com / fs / lustre-release.git / commitdiff