wine-staging/patches/ntdll-futex-condition-var/0001-ntdll-Add-a-futex-based-condition-variable-implement.patch
2018-07-28 13:09:17 +10:00

214 lines
6.8 KiB
Diff

From e50ac69d04c81813a52ac8959db34c4c40f047cb Mon Sep 17 00:00:00 2001
From: Zebediah Figura <z.figura12@gmail.com>
Date: Tue, 24 Jul 2018 11:26:39 -0600
Subject: [PATCH] ntdll: Add a futex-based condition variable implementation.
Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
---
dlls/ntdll/sync.c | 143 +++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 132 insertions(+), 11 deletions(-)
diff --git a/dlls/ntdll/sync.c b/dlls/ntdll/sync.c
index 8e406ce..4752543 100644
--- a/dlls/ntdll/sync.c
+++ b/dlls/ntdll/sync.c
@@ -26,6 +26,7 @@
#include <assert.h>
#include <errno.h>
+#include <limits.h>
#include <signal.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
@@ -36,6 +37,9 @@
#ifdef HAVE_SYS_POLL_H
# include <sys/poll.h>
#endif
+#ifdef HAVE_SYS_SYSCALL_H
+# include <sys/syscall.h>
+#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
@@ -61,6 +65,102 @@ WINE_DEFAULT_DEBUG_CHANNEL(ntdll);
HANDLE keyed_event = NULL;
+#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, const LARGE_INTEGER *timeout)
+{
+ int val, ret;
+
+ if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
+
+ if (timeout && timeout->QuadPart != TIMEOUT_INFINITE)
+ {
+ struct timespec timespec;
+ LONGLONG duration;
+
+ if (timeout->QuadPart > 0)
+ {
+ LARGE_INTEGER now;
+ NtQuerySystemTime( &now );
+ duration = timeout->QuadPart - now.QuadPart;
+ }
+ else
+ duration = -timeout->QuadPart;
+
+ timespec.tv_sec = duration / TICKSPERSEC;
+ timespec.tv_nsec = (duration % TICKSPERSEC) * 100;
+ do
+ val = *((int *)&variable->Ptr);
+ while (val && (ret = futex_wait( (int *)&variable->Ptr, val, &timespec )) == -1
+ && errno == EAGAIN);
+ }
+ else
+ {
+ do
+ val = *((int *)&variable->Ptr);
+ while (val && (ret = futex_wait( (int *)&variable->Ptr, val, NULL )) == -1
+ && errno == EAGAIN);
+ }
+
+ if (ret == -1 && errno == ETIMEDOUT) return STATUS_TIMEOUT;
+ else if (ret == -1) FIXME("got errno %d %s\n", errno, strerror(errno));
+
+ return STATUS_WAIT_0;
+}
+
+static inline NTSTATUS fast_wake( RTL_CONDITION_VARIABLE *variable, int val )
+{
+ if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
+
+ futex_wake( (int *)&variable->Ptr, val );
+ return STATUS_SUCCESS;
+}
+
+#else
+static inline NTSTATUS fast_wait( RTL_CRITICAL_SECTION *crit, int timeout )
+{
+ return STATUS_NOT_IMPLEMENTED;
+}
+
+static inline NTSTATUS fast_wake( RTL_CRITICAL_SECTION *crit )
+{
+ return STATUS_NOT_IMPLEMENTED;
+}
+#endif
+
static inline int interlocked_dec_if_nonzero( int *dest )
{
int val, tmp;
@@ -1814,7 +1914,11 @@ void WINAPI RtlInitializeConditionVariable( RTL_CONDITION_VARIABLE *variable )
void WINAPI RtlWakeConditionVariable( RTL_CONDITION_VARIABLE *variable )
{
if (interlocked_dec_if_nonzero( (int *)&variable->Ptr ))
- NtReleaseKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL );
+ {
+ NTSTATUS ret;
+ if ((ret = fast_wake( variable, 1 )) == STATUS_NOT_IMPLEMENTED)
+ NtReleaseKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL );
+ }
}
/***********************************************************************
@@ -1825,8 +1929,15 @@ 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( keyed_event, &variable->Ptr, FALSE, NULL );
+ if (val)
+ {
+ NTSTATUS ret;
+ if ((ret = fast_wake( variable, INT_MAX )) == STATUS_NOT_IMPLEMENTED)
+ {
+ while (val-- > 0)
+ NtReleaseKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL );
+ }
+ }
}
/***********************************************************************
@@ -1851,12 +1962,17 @@ NTSTATUS WINAPI RtlSleepConditionVariableCS( RTL_CONDITION_VARIABLE *variable, R
interlocked_xchg_add( (int *)&variable->Ptr, 1 );
RtlLeaveCriticalSection( crit );
- status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, timeout );
- if (status != STATUS_SUCCESS)
+ if ((status = fast_wait( variable, timeout )) == STATUS_NOT_IMPLEMENTED)
{
- if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr ))
- status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL );
+ 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;
@@ -1892,12 +2008,17 @@ NTSTATUS WINAPI RtlSleepConditionVariableSRW( RTL_CONDITION_VARIABLE *variable,
else
RtlReleaseSRWLockExclusive( lock );
- status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, timeout );
- if (status != STATUS_SUCCESS)
+ if ((status = fast_wait( variable, timeout )) == STATUS_NOT_IMPLEMENTED)
{
- if (!interlocked_dec_if_nonzero( (int *)&variable->Ptr ))
- status = NtWaitForKeyedEvent( keyed_event, &variable->Ptr, FALSE, NULL );
+ 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 );
--
2.7.4