From a2db3d4e01b9194ae0f79ebb416134a7c8d6bb42 Mon Sep 17 00:00:00 2001 From: Zebediah Figura Date: Tue, 24 Jul 2018 11:26:39 -0600 Subject: [PATCH] ntdll: Add a futex-based condition variable implementation. With significant contributions from Andrew Wesie. --- dlls/ntdll/sync.c | 213 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 185 insertions(+), 28 deletions(-) diff --git a/dlls/ntdll/sync.c b/dlls/ntdll/sync.c index a00a159d24..cef0035850 100644 --- a/dlls/ntdll/sync.c +++ b/dlls/ntdll/sync.c @@ -26,6 +26,7 @@ #include #include +#include #include #ifdef HAVE_SYS_TIME_H # include @@ -36,6 +37,9 @@ #ifdef HAVE_SYS_POLL_H # include #endif +#ifdef HAVE_SYS_SYSCALL_H +# include +#endif #ifdef HAVE_UNISTD_H # include #endif @@ -61,7 +65,140 @@ WINE_DEFAULT_DEBUG_CHANNEL(ntdll); HANDLE keyed_event = NULL; + static const LARGE_INTEGER zero_timeout; +#define TICKSPERSEC 10000000 + +#ifdef __linux__ + +static int wait_op = 128; /*FUTEX_WAIT|FUTEX_PRIVATE_FLAG*/ +static int wake_op = 129; /*FUTEX_WAKE|FUTEX_PRIVATE_FLAG*/ + +static inline int futex_wait( int *addr, int val, struct timespec *timeout ) +{ + return syscall( __NR_futex, addr, wait_op, val, timeout, 0, 0 ); +} + +static inline int futex_wake( int *addr, int val ) +{ + return syscall( __NR_futex, addr, wake_op, val, NULL, 0, 0 ); +} + +static inline int use_futexes(void) +{ + static int supported = -1; + + if (supported == -1) + { + futex_wait( &supported, 10, NULL ); + if (errno == ENOSYS) + { + wait_op = 0; /*FUTEX_WAIT*/ + wake_op = 1; /*FUTEX_WAKE*/ + futex_wait( &supported, 10, NULL ); + } + supported = (errno != ENOSYS); + } + return supported; +} + +static inline NTSTATUS fast_wait( RTL_CONDITION_VARIABLE *variable, int val, + const LARGE_INTEGER *timeout) +{ + struct timespec timespec; + LONGLONG timeleft; + LARGE_INTEGER now; + int ret; + + if (!use_futexes()) return STATUS_NOT_IMPLEMENTED; + + if (timeout && timeout->QuadPart != TIMEOUT_INFINITE) + { + if (timeout->QuadPart >= 0) + { + NtQuerySystemTime( &now ); + timeleft = timeout->QuadPart - now.QuadPart; + if (timeleft < 0) timeleft = 0; + } + else + timeleft = -timeout->QuadPart; + + timespec.tv_sec = timeleft / TICKSPERSEC; + timespec.tv_nsec = (timeleft % TICKSPERSEC) * 100; + + ret = futex_wait( (int *)&variable->Ptr, val, ×pec ); + } + else + ret = futex_wait( (int *)&variable->Ptr, val, NULL ); + + if (ret == -1 && errno == ETIMEDOUT) return STATUS_TIMEOUT; + return STATUS_WAIT_0; +} + +static inline NTSTATUS fast_sleep_cs( RTL_CONDITION_VARIABLE *variable, + RTL_CRITICAL_SECTION *crit, const LARGE_INTEGER *timeout ) +{ + int val = *(int *)&variable->Ptr; + NTSTATUS ret; + + RtlLeaveCriticalSection( crit ); + + ret = fast_wait( variable, val, timeout ); + + RtlEnterCriticalSection( crit ); + + return ret; +} + +static inline NTSTATUS fast_sleep_srw( RTL_CONDITION_VARIABLE *variable, + RTL_SRWLOCK *lock, const LARGE_INTEGER *timeout, ULONG flags ) +{ + int val = *(int *)&variable->Ptr; + NTSTATUS ret; + + if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) + RtlReleaseSRWLockShared( lock ); + else + RtlReleaseSRWLockExclusive( lock ); + + ret = fast_wait( variable, val, timeout ); + + if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) + RtlAcquireSRWLockShared( lock ); + else + RtlAcquireSRWLockExclusive( lock ); + + return ret; +} + +static inline NTSTATUS fast_wake( RTL_CONDITION_VARIABLE *variable, int val ) +{ + if (!use_futexes()) return STATUS_NOT_IMPLEMENTED; + + interlocked_xchg_add( (int *)&variable->Ptr, 1 ); + futex_wake( (int *)&variable->Ptr, val ); + return STATUS_SUCCESS; +} + +#else +static inline NTSTATUS fast_sleep_cs( RTL_CONDITION_VARIABLE *variable, + RTL_CRITICAL_SECTION *crit, const LARGE_INTEGER *timeout ) +{ + return STATUS_NOT_IMPLEMENTED; +} + +static inline NTSTATUS fast_sleep_srw( RTL_CONDITION_VARIABLE *variable, + RTL_SRWLOCK *lock, const LARGE_INTEGER *timeout, ULONG flags ) +{ + return STATUS_NOT_IMPLEMENTED; +} + +static inline NTSTATUS fast_wake( RTL_CONDITION_VARIABLE *variable, int val ) +{ + return STATUS_NOT_IMPLEMENTED; +} +#endif + static inline int interlocked_dec_if_nonzero( int *dest ) { @@ -1867,8 +2004,11 @@ void WINAPI RtlInitializeConditionVariable( RTL_CONDITION_VARIABLE *variable ) */ void WINAPI RtlWakeConditionVariable( RTL_CONDITION_VARIABLE *variable ) { - if (interlocked_dec_if_nonzero( (int *)&variable->Ptr )) - NtReleaseKeyedEvent( 0, &variable->Ptr, FALSE, NULL ); + if (fast_wake( variable, 1 ) == STATUS_NOT_IMPLEMENTED) + { + if (interlocked_dec_if_nonzero( (int *)&variable->Ptr )) + NtReleaseKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL ); + } } /*********************************************************************** @@ -1878,9 +2018,12 @@ void WINAPI RtlWakeConditionVariable( RTL_CONDITION_VARIABLE *variable ) */ void WINAPI RtlWakeAllConditionVariable( RTL_CONDITION_VARIABLE *variable ) { - int val = interlocked_xchg( (int *)&variable->Ptr, 0 ); - while (val-- > 0) - NtReleaseKeyedEvent( 0, &variable->Ptr, FALSE, NULL ); + if (fast_wake( variable, INT_MAX ) == STATUS_NOT_IMPLEMENTED) + { + int val = interlocked_xchg( (int *)&variable->Ptr, 0 ); + while (val-- > 0) + NtReleaseKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL ); + } } /*********************************************************************** @@ -1902,17 +2045,24 @@ NTSTATUS WINAPI RtlSleepConditionVariableCS( RTL_CONDITION_VARIABLE *variable, R const LARGE_INTEGER *timeout ) { NTSTATUS status; - interlocked_xchg_add( (int *)&variable->Ptr, 1 ); - RtlLeaveCriticalSection( crit ); - status = NtWaitForKeyedEvent( 0, &variable->Ptr, FALSE, timeout ); - if (status != STATUS_SUCCESS) + if ((status = fast_sleep_cs( variable, crit, timeout )) == STATUS_NOT_IMPLEMENTED) { - if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr )) - status = NtWaitForKeyedEvent( 0, &variable->Ptr, FALSE, NULL ); - } + interlocked_xchg_add( (int *)&variable->Ptr, 1 ); + RtlLeaveCriticalSection( crit ); - RtlEnterCriticalSection( crit ); + status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, timeout ); + if (status != STATUS_SUCCESS) + { + if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr )) + status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL ); + } + + else if (status != STATUS_SUCCESS) + interlocked_dec_if_nonzero( (int *)&variable->Ptr ); + + RtlEnterCriticalSection( crit ); + } return status; } @@ -1939,24 +2089,31 @@ NTSTATUS WINAPI RtlSleepConditionVariableSRW( RTL_CONDITION_VARIABLE *variable, const LARGE_INTEGER *timeout, ULONG flags ) { NTSTATUS status; - interlocked_xchg_add( (int *)&variable->Ptr, 1 ); - - if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) - RtlReleaseSRWLockShared( lock ); - else - RtlReleaseSRWLockExclusive( lock ); - status = NtWaitForKeyedEvent( 0, &variable->Ptr, FALSE, timeout ); - if (status != STATUS_SUCCESS) + if ((status = fast_sleep_srw( variable, lock, timeout, flags )) == STATUS_NOT_IMPLEMENTED) { - if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr )) - status = NtWaitForKeyedEvent( 0, &variable->Ptr, FALSE, NULL ); - } + interlocked_xchg_add( (int *)&variable->Ptr, 1 ); - if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) - RtlAcquireSRWLockShared( lock ); - else - RtlAcquireSRWLockExclusive( lock ); + if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) + RtlReleaseSRWLockShared( lock ); + else + RtlReleaseSRWLockExclusive( lock ); + + status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, timeout ); + if (status != STATUS_SUCCESS) + { + if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr )) + status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL ); + } + + else if (status != STATUS_SUCCESS) + interlocked_dec_if_nonzero( (int *)&variable->Ptr ); + + if (flags & RTL_CONDITION_VARIABLE_LOCKMODE_SHARED) + RtlAcquireSRWLockShared( lock ); + else + RtlAcquireSRWLockExclusive( lock ); + } return status; } -- 2.19.1