diff options
author | Liang Qi <liang.qi@qt.io> | 2016-05-20 13:46:21 +0200 |
---|---|---|
committer | Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com> | 2016-05-23 21:09:46 +0200 |
commit | 56d6e000f7487c59172330ebd23a718268c508f1 (patch) | |
tree | 1494432583b1569816075091a8075b31d795f77c /src/corelib/thread/qmutex_linux.cpp | |
parent | 9fd407fc6a29c94b4568dd042a05c208255179e0 (diff) | |
parent | c276aa51303b7c6f8e4cd854aadf8344a906e50f (diff) |
Merge remote-tracking branch 'origin/5.7' into dev
Conflicts:
mkspecs/wince80colibri-armv7-msvc2012/qmake.conf
qmake/generators/win32/msvc_vcproj.cpp
src/corelib/global/qnamespace.h
src/corelib/global/qnamespace.qdoc
src/corelib/io/qfsfileengine_win.cpp
src/corelib/tools/tools.pri
src/network/ssl/qsslconfiguration_p.h
src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp
src/plugins/platforms/windows/windows.pri
src/src.pro
src/tools/bootstrap/bootstrap.pro
src/tools/uic/cpp/cppwriteinitialization.cpp
src/widgets/dialogs/qfilesystemmodel.cpp
tests/auto/testlib/selftests/expected_cmptest.teamcity
tests/auto/testlib/selftests/expected_cmptest.txt
Change-Id: I4d2ac78f0dcc97f008186bbbc769c6fe588ab0e5
Diffstat (limited to 'src/corelib/thread/qmutex_linux.cpp')
-rw-r--r-- | src/corelib/thread/qmutex_linux.cpp | 41 |
1 files changed, 6 insertions, 35 deletions
diff --git a/src/corelib/thread/qmutex_linux.cpp b/src/corelib/thread/qmutex_linux.cpp index 89eb3da203..25444ffff6 100644 --- a/src/corelib/thread/qmutex_linux.cpp +++ b/src/corelib/thread/qmutex_linux.cpp @@ -56,6 +56,11 @@ # error "Qt build is broken: qmutex_linux.cpp is being built but futex support is not wanted" #endif +#ifndef FUTEX_PRIVATE_FLAG +# define FUTEX_PRIVATE_FLAG 128 +#endif + + QT_BEGIN_NAMESPACE /* @@ -104,40 +109,6 @@ QT_BEGIN_NAMESPACE static QBasicAtomicInt futexFlagSupport = Q_BASIC_ATOMIC_INITIALIZER(-1); -static int checkFutexPrivateSupport() -{ - int value = 0; -#if defined(FUTEX_PRIVATE_FLAG) - // check if the kernel supports extra futex flags - // FUTEX_PRIVATE_FLAG appeared in v2.6.22 - Q_STATIC_ASSERT(FUTEX_PRIVATE_FLAG != 0x80000000); - - // try an operation that has no side-effects: wake up 42 threads - // futex will return -1 (errno==ENOSYS) if the flag isn't supported - // there should be no other error conditions - value = syscall(__NR_futex, &futexFlagSupport, - FUTEX_WAKE | FUTEX_PRIVATE_FLAG, - 42, 0, 0, 0); - if (value != -1) - value = FUTEX_PRIVATE_FLAG; - else - value = 0; - -#else - value = 0; -#endif - futexFlagSupport.store(value); - return value; -} - -static inline int futexFlags() -{ - int value = futexFlagSupport.load(); - if (Q_LIKELY(value != -1)) - return value; - return checkFutexPrivateSupport(); -} - static inline int _q_futex(void *addr, int op, int val, const struct timespec *timeout) Q_DECL_NOTHROW { volatile int *int_addr = reinterpret_cast<volatile int *>(addr); @@ -149,7 +120,7 @@ static inline int _q_futex(void *addr, int op, int val, const struct timespec *t // we use __NR_futex because some libcs (like Android's bionic) don't // provide SYS_futex etc. - return syscall(__NR_futex, int_addr, op | futexFlags(), val, timeout, addr2, val2); + return syscall(__NR_futex, int_addr, op | FUTEX_PRIVATE_FLAG, val, timeout, addr2, val2); } static inline QMutexData *dummyFutexValue() |