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authorWladimir J. van der Laan <laanwj@gmail.com>2018-08-31 15:49:26 +0200
committerWladimir J. van der Laan <laanwj@gmail.com>2018-08-31 16:00:38 +0200
commit385ad110400bc9646dcf2e38b64b7080182a7344 (patch)
tree92206234d6786857d7cb306fb682f67e960d7b7c /src
parentb012bbe358311cc4a73300ccca41b64272250277 (diff)
parent9c4dc597ddc66acfd58a945a5ab11f833731abba (diff)
Merge #11640: Make LOCK, LOCK2, TRY_LOCK work with CWaitableCriticalSection
9c4dc597ddc66acfd58a945a5ab11f833731abba Use LOCK macros for non-recursive locks (Russell Yanofsky) 1382913e61f5db6ba849b1e261e8aefcd5a1ae68 Make LOCK, LOCK2, TRY_LOCK work with CWaitableCriticalSection (Russell Yanofsky) ba1f095aadf29bddb0bd8176d2e0b908f92a5623 MOVEONLY Move AnnotatedMixin declaration (Russell Yanofsky) 41b88e93375d57db12da923f45f87b9a2db8e730 Add unit test for DEBUG_LOCKORDER code (Russell Yanofsky) Pull request description: Make LOCK macros work with non-recursive mutexes, and use wherever possible for better deadlock detection. Also add unit test for DEBUG_LOCKORDER code. Tree-SHA512: 64ef209307f28ecd0813a283f15c6406138c6ffe7f6cbbd084161044db60e2c099a7d0d2edcd1c5e7770a115e9b931b486e86c9a777bdc96d2e8a9f4dc192942
Diffstat (limited to 'src')
-rw-r--r--src/Makefile.test.include1
-rw-r--r--src/httpserver.cpp8
-rw-r--r--src/init.cpp4
-rw-r--r--src/net.cpp4
-rw-r--r--src/net.h2
-rw-r--r--src/random.cpp7
-rw-r--r--src/rpc/blockchain.cpp8
-rw-r--r--src/rpc/mining.cpp2
-rw-r--r--src/sync.cpp8
-rw-r--r--src/sync.h105
-rw-r--r--src/test/sync_tests.cpp52
-rw-r--r--src/threadinterrupt.cpp6
-rw-r--r--src/threadinterrupt.h4
-rw-r--r--src/validation.cpp2
14 files changed, 143 insertions, 70 deletions
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index abfd66efad..019799eb0b 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -83,6 +83,7 @@ BITCOIN_TESTS =\
test/sigopcount_tests.cpp \
test/skiplist_tests.cpp \
test/streams_tests.cpp \
+ test/sync_tests.cpp \
test/timedata_tests.cpp \
test/torcontrol_tests.cpp \
test/transaction_tests.cpp \
diff --git a/src/httpserver.cpp b/src/httpserver.cpp
index 0fdc3e5ff3..200fcad614 100644
--- a/src/httpserver.cpp
+++ b/src/httpserver.cpp
@@ -69,7 +69,7 @@ class WorkQueue
{
private:
/** Mutex protects entire object */
- std::mutex cs;
+ CWaitableCriticalSection cs;
std::condition_variable cond;
std::deque<std::unique_ptr<WorkItem>> queue;
bool running;
@@ -88,7 +88,7 @@ public:
/** Enqueue a work item */
bool Enqueue(WorkItem* item)
{
- std::unique_lock<std::mutex> lock(cs);
+ LOCK(cs);
if (queue.size() >= maxDepth) {
return false;
}
@@ -102,7 +102,7 @@ public:
while (true) {
std::unique_ptr<WorkItem> i;
{
- std::unique_lock<std::mutex> lock(cs);
+ WAIT_LOCK(cs, lock);
while (running && queue.empty())
cond.wait(lock);
if (!running)
@@ -116,7 +116,7 @@ public:
/** Interrupt and exit loops */
void Interrupt()
{
- std::unique_lock<std::mutex> lock(cs);
+ LOCK(cs);
running = false;
cond.notify_all();
}
diff --git a/src/init.cpp b/src/init.cpp
index bd330459f6..11b36a46e1 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -568,7 +568,7 @@ static void BlockNotifyGenesisWait(bool, const CBlockIndex *pBlockIndex)
{
if (pBlockIndex != nullptr) {
{
- WaitableLock lock_GenesisWait(cs_GenesisWait);
+ LOCK(cs_GenesisWait);
fHaveGenesis = true;
}
condvar_GenesisWait.notify_all();
@@ -1661,7 +1661,7 @@ bool AppInitMain()
// Wait for genesis block to be processed
{
- WaitableLock lock(cs_GenesisWait);
+ WAIT_LOCK(cs_GenesisWait, lock);
// We previously could hang here if StartShutdown() is called prior to
// ThreadImport getting started, so instead we just wait on a timer to
// check ShutdownRequested() regularly.
diff --git a/src/net.cpp b/src/net.cpp
index df2cb54b7a..ad9c5e1d81 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -2065,7 +2065,7 @@ void CConnman::ThreadMessageHandler()
pnode->Release();
}
- std::unique_lock<std::mutex> lock(mutexMsgProc);
+ WAIT_LOCK(mutexMsgProc, lock);
if (!fMoreWork) {
condMsgProc.wait_until(lock, std::chrono::steady_clock::now() + std::chrono::milliseconds(100), [this] { return fMsgProcWake; });
}
@@ -2347,7 +2347,7 @@ bool CConnman::Start(CScheduler& scheduler, const Options& connOptions)
flagInterruptMsgProc = false;
{
- std::unique_lock<std::mutex> lock(mutexMsgProc);
+ LOCK(mutexMsgProc);
fMsgProcWake = false;
}
diff --git a/src/net.h b/src/net.h
index edd2f8cf0d..a5afe6ccfc 100644
--- a/src/net.h
+++ b/src/net.h
@@ -427,7 +427,7 @@ private:
bool fMsgProcWake;
std::condition_variable condMsgProc;
- std::mutex mutexMsgProc;
+ CWaitableCriticalSection mutexMsgProc;
std::atomic<bool> flagInterruptMsgProc;
CThreadInterrupt interruptNet;
diff --git a/src/random.cpp b/src/random.cpp
index 6c5ad5ac96..df7265a963 100644
--- a/src/random.cpp
+++ b/src/random.cpp
@@ -12,6 +12,7 @@
#include <wincrypt.h>
#endif
#include <logging.h> // for LogPrint()
+#include <sync.h> // for WAIT_LOCK
#include <utiltime.h> // for GetTime()
#include <stdlib.h>
@@ -295,7 +296,7 @@ void RandAddSeedSleep()
}
-static std::mutex cs_rng_state;
+static CWaitableCriticalSection cs_rng_state;
static unsigned char rng_state[32] = {0};
static uint64_t rng_counter = 0;
@@ -305,7 +306,7 @@ static void AddDataToRng(void* data, size_t len) {
hasher.Write((const unsigned char*)data, len);
unsigned char buf[64];
{
- std::unique_lock<std::mutex> lock(cs_rng_state);
+ WAIT_LOCK(cs_rng_state, lock);
hasher.Write(rng_state, sizeof(rng_state));
hasher.Write((const unsigned char*)&rng_counter, sizeof(rng_counter));
++rng_counter;
@@ -337,7 +338,7 @@ void GetStrongRandBytes(unsigned char* out, int num)
// Combine with and update state
{
- std::unique_lock<std::mutex> lock(cs_rng_state);
+ WAIT_LOCK(cs_rng_state, lock);
hasher.Write(rng_state, sizeof(rng_state));
hasher.Write((const unsigned char*)&rng_counter, sizeof(rng_counter));
++rng_counter;
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index a77fea8ea8..5b93698951 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -50,7 +50,7 @@ struct CUpdatedBlock
int height;
};
-static std::mutex cs_blockchange;
+static CWaitableCriticalSection cs_blockchange;
static std::condition_variable cond_blockchange;
static CUpdatedBlock latestblock;
@@ -225,7 +225,7 @@ static UniValue waitfornewblock(const JSONRPCRequest& request)
CUpdatedBlock block;
{
- std::unique_lock<std::mutex> lock(cs_blockchange);
+ WAIT_LOCK(cs_blockchange, lock);
block = latestblock;
if(timeout)
cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&block]{return latestblock.height != block.height || latestblock.hash != block.hash || !IsRPCRunning(); });
@@ -267,7 +267,7 @@ static UniValue waitforblock(const JSONRPCRequest& request)
CUpdatedBlock block;
{
- std::unique_lock<std::mutex> lock(cs_blockchange);
+ WAIT_LOCK(cs_blockchange, lock);
if(timeout)
cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&hash]{return latestblock.hash == hash || !IsRPCRunning();});
else
@@ -310,7 +310,7 @@ static UniValue waitforblockheight(const JSONRPCRequest& request)
CUpdatedBlock block;
{
- std::unique_lock<std::mutex> lock(cs_blockchange);
+ WAIT_LOCK(cs_blockchange, lock);
if(timeout)
cond_blockchange.wait_for(lock, std::chrono::milliseconds(timeout), [&height]{return latestblock.height >= height || !IsRPCRunning();});
else
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 623b0bd86a..9cc4e77768 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -470,7 +470,7 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
{
checktxtime = std::chrono::steady_clock::now() + std::chrono::minutes(1);
- WaitableLock lock(g_best_block_mutex);
+ WAIT_LOCK(g_best_block_mutex, lock);
while (g_best_block == hashWatchedChain && IsRPCRunning())
{
if (g_best_block_cv.wait_until(lock, checktxtime) == std::cv_status::timeout)
diff --git a/src/sync.cpp b/src/sync.cpp
index 255eb4f00b..c9aa98dcd6 100644
--- a/src/sync.cpp
+++ b/src/sync.cpp
@@ -100,7 +100,11 @@ static void potential_deadlock_detected(const std::pair<void*, void*>& mismatch,
}
LogPrintf(" %s\n", i.second.ToString());
}
- assert(false);
+ if (g_debug_lockorder_abort) {
+ fprintf(stderr, "Assertion failed: detected inconsistent lock order at %s:%i, details in debug log.\n", __FILE__, __LINE__);
+ abort();
+ }
+ throw std::logic_error("potential deadlock detected");
}
static void push_lock(void* c, const CLockLocation& locklocation)
@@ -189,4 +193,6 @@ void DeleteLock(void* cs)
}
}
+bool g_debug_lockorder_abort = true;
+
#endif /* DEBUG_LOCKORDER */
diff --git a/src/sync.h b/src/sync.h
index 11c1253757..0263816c39 100644
--- a/src/sync.h
+++ b/src/sync.h
@@ -46,14 +46,42 @@ LEAVE_CRITICAL_SECTION(mutex); // no RAII
// //
///////////////////////////////
+#ifdef DEBUG_LOCKORDER
+void EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false);
+void LeaveCritical();
+std::string LocksHeld();
+void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs);
+void AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs);
+void DeleteLock(void* cs);
+
/**
- * Template mixin that adds -Wthread-safety locking
- * annotations to a subset of the mutex API.
+ * Call abort() if a potential lock order deadlock bug is detected, instead of
+ * just logging information and throwing a logic_error. Defaults to true, and
+ * set to false in DEBUG_LOCKORDER unit tests.
+ */
+extern bool g_debug_lockorder_abort;
+#else
+void static inline EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false) {}
+void static inline LeaveCritical() {}
+void static inline AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs) {}
+void static inline AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) {}
+void static inline DeleteLock(void* cs) {}
+#endif
+#define AssertLockHeld(cs) AssertLockHeldInternal(#cs, __FILE__, __LINE__, &cs)
+#define AssertLockNotHeld(cs) AssertLockNotHeldInternal(#cs, __FILE__, __LINE__, &cs)
+
+/**
+ * Template mixin that adds -Wthread-safety locking annotations and lock order
+ * checking to a subset of the mutex API.
*/
template <typename PARENT>
class LOCKABLE AnnotatedMixin : public PARENT
{
public:
+ ~AnnotatedMixin() {
+ DeleteLock((void*)this);
+ }
+
void lock() EXCLUSIVE_LOCK_FUNCTION()
{
PARENT::lock();
@@ -68,36 +96,15 @@ public:
{
return PARENT::try_lock();
}
-};
-#ifdef DEBUG_LOCKORDER
-void EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false);
-void LeaveCritical();
-std::string LocksHeld();
-void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs);
-void AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs);
-void DeleteLock(void* cs);
-#else
-void static inline EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false) {}
-void static inline LeaveCritical() {}
-void static inline AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs) {}
-void static inline AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) {}
-void static inline DeleteLock(void* cs) {}
-#endif
-#define AssertLockHeld(cs) AssertLockHeldInternal(#cs, __FILE__, __LINE__, &cs)
-#define AssertLockNotHeld(cs) AssertLockNotHeldInternal(#cs, __FILE__, __LINE__, &cs)
+ using UniqueLock = std::unique_lock<PARENT>;
+};
/**
* Wrapped mutex: supports recursive locking, but no waiting
* TODO: We should move away from using the recursive lock by default.
*/
-class CCriticalSection : public AnnotatedMixin<std::recursive_mutex>
-{
-public:
- ~CCriticalSection() {
- DeleteLock((void*)this);
- }
-};
+typedef AnnotatedMixin<std::recursive_mutex> CCriticalSection;
/** Wrapped mutex: supports waiting but not recursive locking */
typedef AnnotatedMixin<std::mutex> CWaitableCriticalSection;
@@ -105,27 +112,23 @@ typedef AnnotatedMixin<std::mutex> CWaitableCriticalSection;
/** Just a typedef for std::condition_variable, can be wrapped later if desired */
typedef std::condition_variable CConditionVariable;
-/** Just a typedef for std::unique_lock, can be wrapped later if desired */
-typedef std::unique_lock<std::mutex> WaitableLock;
-
#ifdef DEBUG_LOCKCONTENTION
void PrintLockContention(const char* pszName, const char* pszFile, int nLine);
#endif
-/** Wrapper around std::unique_lock<CCriticalSection> */
-class SCOPED_LOCKABLE CCriticalBlock
+/** Wrapper around std::unique_lock style lock for Mutex. */
+template <typename Mutex, typename Base = typename Mutex::UniqueLock>
+class SCOPED_LOCKABLE CCriticalBlock : public Base
{
private:
- std::unique_lock<CCriticalSection> lock;
-
void Enter(const char* pszName, const char* pszFile, int nLine)
{
- EnterCritical(pszName, pszFile, nLine, (void*)(lock.mutex()));
+ EnterCritical(pszName, pszFile, nLine, (void*)(Base::mutex()));
#ifdef DEBUG_LOCKCONTENTION
- if (!lock.try_lock()) {
+ if (!Base::try_lock()) {
PrintLockContention(pszName, pszFile, nLine);
#endif
- lock.lock();
+ Base::lock();
#ifdef DEBUG_LOCKCONTENTION
}
#endif
@@ -133,15 +136,15 @@ private:
bool TryEnter(const char* pszName, const char* pszFile, int nLine)
{
- EnterCritical(pszName, pszFile, nLine, (void*)(lock.mutex()), true);
- lock.try_lock();
- if (!lock.owns_lock())
+ EnterCritical(pszName, pszFile, nLine, (void*)(Base::mutex()), true);
+ Base::try_lock();
+ if (!Base::owns_lock())
LeaveCritical();
- return lock.owns_lock();
+ return Base::owns_lock();
}
public:
- CCriticalBlock(CCriticalSection& mutexIn, const char* pszName, const char* pszFile, int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(mutexIn) : lock(mutexIn, std::defer_lock)
+ CCriticalBlock(Mutex& mutexIn, const char* pszName, const char* pszFile, int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(mutexIn) : Base(mutexIn, std::defer_lock)
{
if (fTry)
TryEnter(pszName, pszFile, nLine);
@@ -149,11 +152,11 @@ public:
Enter(pszName, pszFile, nLine);
}
- CCriticalBlock(CCriticalSection* pmutexIn, const char* pszName, const char* pszFile, int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(pmutexIn)
+ CCriticalBlock(Mutex* pmutexIn, const char* pszName, const char* pszFile, int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(pmutexIn)
{
if (!pmutexIn) return;
- lock = std::unique_lock<CCriticalSection>(*pmutexIn, std::defer_lock);
+ *static_cast<Base*>(this) = Base(*pmutexIn, std::defer_lock);
if (fTry)
TryEnter(pszName, pszFile, nLine);
else
@@ -162,22 +165,28 @@ public:
~CCriticalBlock() UNLOCK_FUNCTION()
{
- if (lock.owns_lock())
+ if (Base::owns_lock())
LeaveCritical();
}
operator bool()
{
- return lock.owns_lock();
+ return Base::owns_lock();
}
};
+template<typename MutexArg>
+using DebugLock = CCriticalBlock<typename std::remove_reference<typename std::remove_pointer<MutexArg>::type>::type>;
+
#define PASTE(x, y) x ## y
#define PASTE2(x, y) PASTE(x, y)
-#define LOCK(cs) CCriticalBlock PASTE2(criticalblock, __COUNTER__)(cs, #cs, __FILE__, __LINE__)
-#define LOCK2(cs1, cs2) CCriticalBlock criticalblock1(cs1, #cs1, __FILE__, __LINE__), criticalblock2(cs2, #cs2, __FILE__, __LINE__)
-#define TRY_LOCK(cs, name) CCriticalBlock name(cs, #cs, __FILE__, __LINE__, true)
+#define LOCK(cs) DebugLock<decltype(cs)> PASTE2(criticalblock, __COUNTER__)(cs, #cs, __FILE__, __LINE__)
+#define LOCK2(cs1, cs2) \
+ DebugLock<decltype(cs1)> criticalblock1(cs1, #cs1, __FILE__, __LINE__); \
+ DebugLock<decltype(cs2)> criticalblock2(cs2, #cs2, __FILE__, __LINE__);
+#define TRY_LOCK(cs, name) DebugLock<decltype(cs)> name(cs, #cs, __FILE__, __LINE__, true)
+#define WAIT_LOCK(cs, name) DebugLock<decltype(cs)> name(cs, #cs, __FILE__, __LINE__)
#define ENTER_CRITICAL_SECTION(cs) \
{ \
diff --git a/src/test/sync_tests.cpp b/src/test/sync_tests.cpp
new file mode 100644
index 0000000000..539e2ff3ab
--- /dev/null
+++ b/src/test/sync_tests.cpp
@@ -0,0 +1,52 @@
+// Copyright (c) 2012-2017 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <sync.h>
+#include <test/test_bitcoin.h>
+
+#include <boost/test/unit_test.hpp>
+
+namespace {
+template <typename MutexType>
+void TestPotentialDeadLockDetected(MutexType& mutex1, MutexType& mutex2)
+{
+ {
+ LOCK2(mutex1, mutex2);
+ }
+ bool error_thrown = false;
+ try {
+ LOCK2(mutex2, mutex1);
+ } catch (const std::logic_error& e) {
+ BOOST_CHECK_EQUAL(e.what(), "potential deadlock detected");
+ error_thrown = true;
+ }
+ #ifdef DEBUG_LOCKORDER
+ BOOST_CHECK(error_thrown);
+ #else
+ BOOST_CHECK(!error_thrown);
+ #endif
+}
+} // namespace
+
+BOOST_FIXTURE_TEST_SUITE(sync_tests, BasicTestingSetup)
+
+BOOST_AUTO_TEST_CASE(potential_deadlock_detected)
+{
+ #ifdef DEBUG_LOCKORDER
+ bool prev = g_debug_lockorder_abort;
+ g_debug_lockorder_abort = false;
+ #endif
+
+ CCriticalSection rmutex1, rmutex2;
+ TestPotentialDeadLockDetected(rmutex1, rmutex2);
+
+ CWaitableCriticalSection mutex1, mutex2;
+ TestPotentialDeadLockDetected(mutex1, mutex2);
+
+ #ifdef DEBUG_LOCKORDER
+ g_debug_lockorder_abort = prev;
+ #endif
+}
+
+BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/threadinterrupt.cpp b/src/threadinterrupt.cpp
index d08d52e4a9..340106ed99 100644
--- a/src/threadinterrupt.cpp
+++ b/src/threadinterrupt.cpp
@@ -5,6 +5,8 @@
#include <threadinterrupt.h>
+#include <sync.h>
+
CThreadInterrupt::CThreadInterrupt() : flag(false) {}
CThreadInterrupt::operator bool() const
@@ -20,7 +22,7 @@ void CThreadInterrupt::reset()
void CThreadInterrupt::operator()()
{
{
- std::unique_lock<std::mutex> lock(mut);
+ LOCK(mut);
flag.store(true, std::memory_order_release);
}
cond.notify_all();
@@ -28,7 +30,7 @@ void CThreadInterrupt::operator()()
bool CThreadInterrupt::sleep_for(std::chrono::milliseconds rel_time)
{
- std::unique_lock<std::mutex> lock(mut);
+ WAIT_LOCK(mut, lock);
return !cond.wait_for(lock, rel_time, [this]() { return flag.load(std::memory_order_acquire); });
}
diff --git a/src/threadinterrupt.h b/src/threadinterrupt.h
index c30bd3d657..a37da956e5 100644
--- a/src/threadinterrupt.h
+++ b/src/threadinterrupt.h
@@ -5,6 +5,8 @@
#ifndef BITCOIN_THREADINTERRUPT_H
#define BITCOIN_THREADINTERRUPT_H
+#include <sync.h>
+
#include <atomic>
#include <chrono>
#include <condition_variable>
@@ -28,7 +30,7 @@ public:
private:
std::condition_variable cond;
- std::mutex mut;
+ CWaitableCriticalSection mut;
std::atomic<bool> flag;
};
diff --git a/src/validation.cpp b/src/validation.cpp
index f6257ffaed..b71b0782c3 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2239,7 +2239,7 @@ void static UpdateTip(const CBlockIndex *pindexNew, const CChainParams& chainPar
mempool.AddTransactionsUpdated(1);
{
- WaitableLock lock(g_best_block_mutex);
+ LOCK(g_best_block_mutex);
g_best_block = pindexNew->GetBlockHash();
g_best_block_cv.notify_all();
}