1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kReplication
#include "mongo/platform/basic.h"
#include "mongo/db/concurrency/replication_state_transition_lock_guard.h"
#include "mongo/db/operation_context.h"
namespace mongo {
namespace repl {
ReplicationStateTransitionLockGuard::ReplicationStateTransitionLockGuard(OperationContext* opCtx)
: ReplicationStateTransitionLockGuard(opCtx, EnqueueOnly()) {
waitForLockUntil(Date_t::max());
}
ReplicationStateTransitionLockGuard::ReplicationStateTransitionLockGuard(OperationContext* opCtx,
EnqueueOnly)
: _opCtx(opCtx) {
_enqueueLock();
}
ReplicationStateTransitionLockGuard::ReplicationStateTransitionLockGuard(
ReplicationStateTransitionLockGuard&& other)
: _opCtx(other._opCtx), _result(other._result) {
other._result = LOCK_INVALID;
}
ReplicationStateTransitionLockGuard::~ReplicationStateTransitionLockGuard() {
_unlock();
}
void ReplicationStateTransitionLockGuard::waitForLockUntil(mongo::Date_t deadline) {
// We can return early if the lock request was already satisfied.
if (_result == LOCK_OK) {
return;
}
// Wait for the completion of the lock request for the RSTL in mode X.
_result = _opCtx->lockState()->lockRSTLComplete(_opCtx, deadline);
uassert(ErrorCodes::ExceededTimeLimit,
"Could not acquire the RSTL before the deadline",
_opCtx->lockState()->isRSTLExclusive());
}
void ReplicationStateTransitionLockGuard::release() {
_unlock();
}
void ReplicationStateTransitionLockGuard::reacquire() {
_enqueueLock();
waitForLockUntil(Date_t::max());
}
void ReplicationStateTransitionLockGuard::_enqueueLock() {
// Enqueue a lock request for the RSTL in mode X.
_result = _opCtx->lockState()->lockRSTLBegin(_opCtx);
}
void ReplicationStateTransitionLockGuard::_unlock() {
// waitForLockUntil() must be called after enqueue. It either times out or succeeds,
// so we should never see LOCK_WAITING here. This also means between the enqueue and
// waitForLockUntil(), no exception is accepted. We could call lockRSTLComplete() with
// timeout 0 here for pending locks to clean up the lock's state, but it's clearer to enforce
// the exception-free pattern.
invariant(_result != LOCK_WAITING);
if (isLocked()) {
_opCtx->lockState()->unlock(resourceIdReplicationStateTransitionLock);
}
_result = LOCK_INVALID;
}
} // namespace repl
} // namespace mongo
|
