* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
- * Copyright (c) 2011, 2013, Intel Corporation.
+ * Copyright (c) 2011, 2017, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
enum ldlm_mode req_mode = req->l_req_mode;
struct ldlm_lock *lock, *next_lock;
int compat = 1;
- ENTRY;
+ ENTRY;
lockmode_verify(req_mode);
list_for_each_entry_safe(lock, next_lock, queue, l_res_link) {
- /* We stop walking the queue if we hit ourselves so we don't
+ /*
+ * We stop walking the queue if we hit ourselves so we don't
* take conflicting locks enqueued after us into account,
- * or we'd wait forever. */
+ * or we'd wait forever.
+ */
if (req == lock)
RETURN(compat);
struct ldlm_lock, l_res_link);
if (lockmode_compat(lock->l_req_mode, req_mode))
- continue;
+ continue;
- if (!work_list)
- RETURN(0);
+ if (!work_list)
+ RETURN(0);
- compat = 0;
+ compat = 0;
- /* Add locks of the mode group to \a work_list as
- * blocking locks for \a req. */
- if (lock->l_blocking_ast)
- ldlm_add_ast_work_item(lock, req, work_list);
+ /*
+ * Add locks of the mode group to \a work_list as
+ * blocking locks for \a req.
+ */
+ if (lock->l_blocking_ast)
+ ldlm_add_ast_work_item(lock, req, work_list);
- {
+ {
struct list_head *head;
- head = &lock->l_sl_mode;
+ head = &lock->l_sl_mode;
list_for_each_entry(lock, head, l_sl_mode)
- if (lock->l_blocking_ast)
- ldlm_add_ast_work_item(lock, req,
- work_list);
- }
- }
+ if (lock->l_blocking_ast)
+ ldlm_add_ast_work_item(lock, req,
+ work_list);
+ }
+ }
- RETURN(compat);
+ RETURN(compat);
}
/**
* This function looks for any conflicts for \a lock in the granted or
* waiting queues. The lock is granted if no conflicts are found in
* either queue.
- *
- * If \a first_enq is 0 (ie, called from ldlm_reprocess_queue):
- * - blocking ASTs have already been sent
- *
- * If \a first_enq is 1 (ie, called from ldlm_lock_enqueue):
- * - blocking ASTs have not been sent yet, so list of conflicting locks
- * would be collected and ASTs sent.
*/
int ldlm_process_plain_lock(struct ldlm_lock *lock, __u64 *flags,
- int first_enq, enum ldlm_error *err,
- struct list_head *work_list)
+ enum ldlm_process_intention intention,
+ enum ldlm_error *err, struct list_head *work_list)
{
struct ldlm_resource *res = lock->l_resource;
- struct list_head rpc_list;
+ struct list_head *grant_work = intention == LDLM_PROCESS_ENQUEUE ?
+ NULL : work_list;
int rc;
- ENTRY;
- LASSERT(lock->l_granted_mode != lock->l_req_mode);
+ ENTRY;
+ LASSERT(!ldlm_is_granted(lock));
check_res_locked(res);
- LASSERT(list_empty(&res->lr_converting));
- INIT_LIST_HEAD(&rpc_list);
-
- if (!first_enq) {
- LASSERT(work_list != NULL);
- rc = ldlm_plain_compat_queue(&res->lr_granted, lock, NULL);
- if (!rc)
- RETURN(LDLM_ITER_STOP);
- rc = ldlm_plain_compat_queue(&res->lr_waiting, lock, NULL);
- if (!rc)
- RETURN(LDLM_ITER_STOP);
-
- ldlm_resource_unlink_lock(lock);
- ldlm_grant_lock(lock, work_list);
- RETURN(LDLM_ITER_CONTINUE);
- }
-
- restart:
- rc = ldlm_plain_compat_queue(&res->lr_granted, lock, &rpc_list);
- rc += ldlm_plain_compat_queue(&res->lr_waiting, lock, &rpc_list);
-
- if (rc != 2) {
- /* If either of the compat_queue()s returned 0, then we
- * have ASTs to send and must go onto the waiting list.
- *
- * bug 2322: we used to unlink and re-add here, which was a
- * terrible folly -- if we goto restart, we could get
- * re-ordered! Causes deadlock, because ASTs aren't sent! */
- if (list_empty(&lock->l_res_link))
- ldlm_resource_add_lock(res, &res->lr_waiting, lock);
- unlock_res(res);
- rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list,
- LDLM_WORK_BL_AST);
- lock_res(res);
- if (rc == -ERESTART)
- GOTO(restart, rc);
- *flags |= LDLM_FL_BLOCK_GRANTED;
- } else {
- ldlm_resource_unlink_lock(lock);
- ldlm_grant_lock(lock, NULL);
- }
- RETURN(0);
+ *err = ELDLM_OK;
+
+ if (intention == LDLM_PROCESS_RESCAN) {
+ LASSERT(work_list != NULL);
+ rc = ldlm_plain_compat_queue(&res->lr_granted, lock, NULL);
+ if (!rc)
+ RETURN(LDLM_ITER_STOP);
+ rc = ldlm_plain_compat_queue(&res->lr_waiting, lock, NULL);
+ if (!rc)
+ RETURN(LDLM_ITER_STOP);
+
+ ldlm_resource_unlink_lock(lock);
+ ldlm_grant_lock(lock, grant_work);
+ RETURN(LDLM_ITER_CONTINUE);
+ }
+
+ rc = ldlm_plain_compat_queue(&res->lr_granted, lock, work_list);
+ rc += ldlm_plain_compat_queue(&res->lr_waiting, lock, work_list);
+
+ if (rc == 2) {
+ ldlm_resource_unlink_lock(lock);
+ ldlm_grant_lock(lock, grant_work);
+ }
+
+ RETURN(LDLM_ITER_CONTINUE);
}
#endif /* HAVE_SERVER_SUPPORT */
git://git.whamcloud.com / fs / lustre-release.git / blobdiff