[PATCH 5/5] ntdll: Reimplement SRW locks on top of Win32 futexes.
Zebediah Figura
zfigura at codeweavers.com
Wed Nov 17 20:18:57 CST 2021
Signed-off-by: Zebediah Figura <zfigura at codeweavers.com>
---
dlls/ntdll/sync.c | 313 +++++++++++++++------------------
dlls/ntdll/unix/loader.c | 6 -
dlls/ntdll/unix/sync.c | 308 --------------------------------
dlls/ntdll/unix/unix_private.h | 6 -
dlls/ntdll/unixlib.h | 10 +-
5 files changed, 142 insertions(+), 501 deletions(-)
diff --git a/dlls/ntdll/sync.c b/dlls/ntdll/sync.c
index 4ceadebf0e7..bdb39e59d6d 100644
--- a/dlls/ntdll/sync.c
+++ b/dlls/ntdll/sync.c
@@ -503,127 +503,24 @@ DWORD WINAPI RtlRunOnceExecuteOnce( RTL_RUN_ONCE *once, PRTL_RUN_ONCE_INIT_FN fu
return RtlRunOnceComplete( once, 0, context ? *context : NULL );
}
-
-/* SRW locks implementation
- *
- * The memory layout used by the lock is:
- *
- * 32 31 16 0
- * ________________ ________________
- * | X| #exclusive | #shared |
- * ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
- * Since there is no space left for a separate counter of shared access
- * threads inside the locked section the #shared field is used for multiple
- * purposes. The following table lists all possible states the lock can be
- * in, notation: [X, #exclusive, #shared]:
- *
- * [0, 0, N] -> locked by N shared access threads, if N=0 it's unlocked
- * [0, >=1, >=1] -> threads are requesting exclusive locks, but there are
- * still shared access threads inside. #shared should not be incremented
- * anymore!
- * [1, >=1, >=0] -> lock is owned by an exclusive thread and the #shared
- * counter can be used again to count the number of threads waiting in the
- * queue for shared access.
- *
- * the following states are invalid and will never occur:
- * [0, >=1, 0], [1, 0, >=0]
- *
- * The main problem arising from the fact that we have no separate counter
- * of shared access threads inside the locked section is that in the state
- * [0, >=1, >=1] above we cannot add additional waiting threads to the
- * shared access queue - it wouldn't be possible to distinguish waiting
- * threads and those that are still inside. To solve this problem the lock
- * uses the following approach: a thread that isn't able to allocate a
- * shared lock just uses the exclusive queue instead. As soon as the thread
- * is woken up it is in the state [1, >=1, >=0]. In this state it's again
- * possible to use the shared access queue. The thread atomically moves
- * itself to the shared access queue and releases the exclusive lock, so
- * that the "real" exclusive access threads have a chance. As soon as they
- * are all ready the shared access threads are processed.
- */
-
-#define SRWLOCK_MASK_IN_EXCLUSIVE 0x80000000
-#define SRWLOCK_MASK_EXCLUSIVE_QUEUE 0x7fff0000
-#define SRWLOCK_MASK_SHARED_QUEUE 0x0000ffff
-#define SRWLOCK_RES_EXCLUSIVE 0x00010000
-#define SRWLOCK_RES_SHARED 0x00000001
-
-#ifdef WORDS_BIGENDIAN
-#define srwlock_key_exclusive(lock) ((void *)(((ULONG_PTR)&lock->Ptr + 1) & ~1))
-#define srwlock_key_shared(lock) ((void *)(((ULONG_PTR)&lock->Ptr + 3) & ~1))
-#else
-#define srwlock_key_exclusive(lock) ((void *)(((ULONG_PTR)&lock->Ptr + 3) & ~1))
-#define srwlock_key_shared(lock) ((void *)(((ULONG_PTR)&lock->Ptr + 1) & ~1))
-#endif
-
-static inline void srwlock_check_invalid( unsigned int val )
+struct srw_lock
{
- /* Throw exception if it's impossible to acquire/release this lock. */
- if ((val & SRWLOCK_MASK_EXCLUSIVE_QUEUE) == SRWLOCK_MASK_EXCLUSIVE_QUEUE ||
- (val & SRWLOCK_MASK_SHARED_QUEUE) == SRWLOCK_MASK_SHARED_QUEUE)
- RtlRaiseStatus(STATUS_RESOURCE_NOT_OWNED);
-}
+ short exclusive_waiters;
-static inline unsigned int srwlock_lock_exclusive( unsigned int *dest, int incr )
-{
- unsigned int val, tmp;
- /* Atomically modifies the value of *dest by adding incr. If the shared
- * queue is empty and there are threads waiting for exclusive access, then
- * sets the mark SRWLOCK_MASK_IN_EXCLUSIVE to signal other threads that
- * they are allowed again to use the shared queue counter. */
- for (val = *dest;; val = tmp)
- {
- tmp = val + incr;
- srwlock_check_invalid( tmp );
- if ((tmp & SRWLOCK_MASK_EXCLUSIVE_QUEUE) && !(tmp & SRWLOCK_MASK_SHARED_QUEUE))
- tmp |= SRWLOCK_MASK_IN_EXCLUSIVE;
- if ((tmp = InterlockedCompareExchange( (int *)dest, tmp, val )) == val)
- break;
- }
- return val;
-}
-
-static inline unsigned int srwlock_unlock_exclusive( unsigned int *dest, int incr )
-{
- unsigned int val, tmp;
- /* Atomically modifies the value of *dest by adding incr. If the queue of
- * threads waiting for exclusive access is empty, then remove the
- * SRWLOCK_MASK_IN_EXCLUSIVE flag (only the shared queue counter will
- * remain). */
- for (val = *dest;; val = tmp)
- {
- tmp = val + incr;
- srwlock_check_invalid( tmp );
- if (!(tmp & SRWLOCK_MASK_EXCLUSIVE_QUEUE))
- tmp &= SRWLOCK_MASK_SHARED_QUEUE;
- if ((tmp = InterlockedCompareExchange( (int *)dest, tmp, val )) == val)
- break;
- }
- return val;
-}
-
-static inline void srwlock_leave_exclusive( RTL_SRWLOCK *lock, unsigned int val )
-{
- /* Used when a thread leaves an exclusive section. If there are other
- * exclusive access threads they are processed first, followed by
- * the shared waiters. */
- if (val & SRWLOCK_MASK_EXCLUSIVE_QUEUE)
- NtReleaseKeyedEvent( 0, srwlock_key_exclusive(lock), FALSE, NULL );
- else
- {
- val &= SRWLOCK_MASK_SHARED_QUEUE; /* remove SRWLOCK_MASK_IN_EXCLUSIVE */
- while (val--)
- NtReleaseKeyedEvent( 0, srwlock_key_shared(lock), FALSE, NULL );
- }
-}
-
-static inline void srwlock_leave_shared( RTL_SRWLOCK *lock, unsigned int val )
-{
- /* Wake up one exclusive thread as soon as the last shared access thread
- * has left. */
- if ((val & SRWLOCK_MASK_EXCLUSIVE_QUEUE) && !(val & SRWLOCK_MASK_SHARED_QUEUE))
- NtReleaseKeyedEvent( 0, srwlock_key_exclusive(lock), FALSE, NULL );
-}
+ /* Number of shared owners, or -1 if owned exclusive.
+ *
+ * Sadly Windows has no equivalent to FUTEX_WAIT_BITSET, so in order to wake
+ * up *only* exclusive or *only* shared waiters (and thus avoid spurious
+ * wakeups), we need to wait on two different addresses.
+ * RtlAcquireSRWLockShared() needs to know the values of "exclusive_waiters"
+ * and "owners", but RtlAcquireSRWLockExclusive() only needs to know the
+ * value of "owners", so the former can wait on the entire structure, and
+ * the latter waits only on the "owners" member. Note then that "owners"
+ * must not be the first element in the structure.
+ */
+ short owners;
+};
+C_ASSERT( sizeof(struct srw_lock) == 4 );
/***********************************************************************
* RtlInitializeSRWLock (NTDLL.@)
@@ -650,11 +547,36 @@ void WINAPI RtlInitializeSRWLock( RTL_SRWLOCK *lock )
*/
void WINAPI RtlAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
{
- if (unix_funcs->fast_RtlAcquireSRWLockExclusive( lock ) != STATUS_NOT_IMPLEMENTED)
- return;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
- if (srwlock_lock_exclusive( (unsigned int *)&lock->Ptr, SRWLOCK_RES_EXCLUSIVE ))
- NtWaitForKeyedEvent( 0, srwlock_key_exclusive(lock), FALSE, NULL );
+ InterlockedIncrement16( &u.s->exclusive_waiters );
+
+ for (;;)
+ {
+ union { struct srw_lock s; LONG l; } old, new;
+ BOOL wait;
+
+ do
+ {
+ old.s = *u.s;
+ new.s = old.s;
+
+ if (!old.s.owners)
+ {
+ /* Not locked exclusive or shared. We can try to grab it. */
+ new.s.owners = -1;
+ --new.s.exclusive_waiters;
+ wait = FALSE;
+ }
+ else
+ {
+ wait = TRUE;
+ }
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ if (!wait) return;
+ RtlWaitOnAddress( &u.s->owners, &new.s.owners, sizeof(short), NULL );
+ }
}
/***********************************************************************
@@ -666,34 +588,34 @@ void WINAPI RtlAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
*/
void WINAPI RtlAcquireSRWLockShared( RTL_SRWLOCK *lock )
{
- unsigned int val, tmp;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
- if (unix_funcs->fast_RtlAcquireSRWLockShared( lock ) != STATUS_NOT_IMPLEMENTED)
- return;
-
- /* Acquires a shared lock. If it's currently not possible to add elements to
- * the shared queue, then request exclusive access instead. */
- for (val = *(unsigned int *)&lock->Ptr;; val = tmp)
+ for (;;)
{
- if ((val & SRWLOCK_MASK_EXCLUSIVE_QUEUE) && !(val & SRWLOCK_MASK_IN_EXCLUSIVE))
- tmp = val + SRWLOCK_RES_EXCLUSIVE;
- else
- tmp = val + SRWLOCK_RES_SHARED;
- if ((tmp = InterlockedCompareExchange( (int *)&lock->Ptr, tmp, val )) == val)
- break;
- }
+ union { struct srw_lock s; LONG l; } old, new;
+ BOOL wait;
- /* Drop exclusive access again and instead requeue for shared access. */
- if ((val & SRWLOCK_MASK_EXCLUSIVE_QUEUE) && !(val & SRWLOCK_MASK_IN_EXCLUSIVE))
- {
- NtWaitForKeyedEvent( 0, srwlock_key_exclusive(lock), FALSE, NULL );
- val = srwlock_unlock_exclusive( (unsigned int *)&lock->Ptr, (SRWLOCK_RES_SHARED
- - SRWLOCK_RES_EXCLUSIVE) ) - SRWLOCK_RES_EXCLUSIVE;
- srwlock_leave_exclusive( lock, val );
- }
+ do
+ {
+ old.s = *u.s;
+ new = old;
- if (val & SRWLOCK_MASK_EXCLUSIVE_QUEUE)
- NtWaitForKeyedEvent( 0, srwlock_key_shared(lock), FALSE, NULL );
+ if (old.s.owners != -1 && !old.s.exclusive_waiters)
+ {
+ /* Not locked exclusive, and no exclusive waiters.
+ * We can try to grab it. */
+ ++new.s.owners;
+ wait = FALSE;
+ }
+ else
+ {
+ wait = TRUE;
+ }
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ if (!wait) return;
+ RtlWaitOnAddress( u.s, &new.s, sizeof(struct srw_lock), NULL );
+ }
}
/***********************************************************************
@@ -701,11 +623,23 @@ void WINAPI RtlAcquireSRWLockShared( RTL_SRWLOCK *lock )
*/
void WINAPI RtlReleaseSRWLockExclusive( RTL_SRWLOCK *lock )
{
- if (unix_funcs->fast_RtlReleaseSRWLockExclusive( lock ) != STATUS_NOT_IMPLEMENTED)
- return;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
+ union { struct srw_lock s; LONG l; } old, new;
- srwlock_leave_exclusive( lock, srwlock_unlock_exclusive( (unsigned int *)&lock->Ptr,
- - SRWLOCK_RES_EXCLUSIVE ) - SRWLOCK_RES_EXCLUSIVE );
+ do
+ {
+ old.s = *u.s;
+ new = old;
+
+ if (old.s.owners != -1) ERR("Lock %p is not owned exclusive!\n", lock);
+
+ new.s.owners = 0;
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ if (new.s.exclusive_waiters)
+ RtlWakeAddressSingle( &u.s->owners );
+ else
+ RtlWakeAddressAll( u.s );
}
/***********************************************************************
@@ -713,11 +647,22 @@ void WINAPI RtlReleaseSRWLockExclusive( RTL_SRWLOCK *lock )
*/
void WINAPI RtlReleaseSRWLockShared( RTL_SRWLOCK *lock )
{
- if (unix_funcs->fast_RtlReleaseSRWLockShared( lock ) != STATUS_NOT_IMPLEMENTED)
- return;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
+ union { struct srw_lock s; LONG l; } old, new;
- srwlock_leave_shared( lock, srwlock_lock_exclusive( (unsigned int *)&lock->Ptr,
- - SRWLOCK_RES_SHARED ) - SRWLOCK_RES_SHARED );
+ do
+ {
+ old.s = *u.s;
+ new = old;
+
+ if (old.s.owners == -1) ERR("Lock %p is owned exclusive!\n", lock);
+ else if (!old.s.owners) ERR("Lock %p is not owned shared!\n", lock);
+
+ --new.s.owners;
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ if (!new.s.owners)
+ RtlWakeAddressSingle( &u.s->owners );
}
/***********************************************************************
@@ -729,13 +674,28 @@ void WINAPI RtlReleaseSRWLockShared( RTL_SRWLOCK *lock )
*/
BOOLEAN WINAPI RtlTryAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
{
- NTSTATUS ret;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
+ union { struct srw_lock s; LONG l; } old, new;
+ BOOLEAN ret;
- if ((ret = unix_funcs->fast_RtlTryAcquireSRWLockExclusive( lock )) != STATUS_NOT_IMPLEMENTED)
- return (ret == STATUS_SUCCESS);
+ do
+ {
+ old.s = *u.s;
+ new.s = old.s;
- return InterlockedCompareExchange( (int *)&lock->Ptr, SRWLOCK_MASK_IN_EXCLUSIVE |
- SRWLOCK_RES_EXCLUSIVE, 0 ) == 0;
+ if (!old.s.owners)
+ {
+ /* Not locked exclusive or shared. We can try to grab it. */
+ new.s.owners = -1;
+ ret = TRUE;
+ }
+ else
+ {
+ ret = FALSE;
+ }
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ return ret;
}
/***********************************************************************
@@ -743,20 +703,29 @@ BOOLEAN WINAPI RtlTryAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
*/
BOOLEAN WINAPI RtlTryAcquireSRWLockShared( RTL_SRWLOCK *lock )
{
- unsigned int val, tmp;
- NTSTATUS ret;
+ union { RTL_SRWLOCK *rtl; struct srw_lock *s; LONG *l; } u = { lock };
+ union { struct srw_lock s; LONG l; } old, new;
+ BOOLEAN ret;
- if ((ret = unix_funcs->fast_RtlTryAcquireSRWLockShared( lock )) != STATUS_NOT_IMPLEMENTED)
- return (ret == STATUS_SUCCESS);
-
- for (val = *(unsigned int *)&lock->Ptr;; val = tmp)
+ do
{
- if (val & SRWLOCK_MASK_EXCLUSIVE_QUEUE)
- return FALSE;
- if ((tmp = InterlockedCompareExchange( (int *)&lock->Ptr, val + SRWLOCK_RES_SHARED, val )) == val)
- break;
- }
- return TRUE;
+ old.s = *u.s;
+ new.s = old.s;
+
+ if (old.s.owners != -1 && !old.s.exclusive_waiters)
+ {
+ /* Not locked exclusive, and no exclusive waiters.
+ * We can try to grab it. */
+ ++new.s.owners;
+ ret = TRUE;
+ }
+ else
+ {
+ ret = FALSE;
+ }
+ } while (InterlockedCompareExchange( u.l, new.l, old.l ) != old.l);
+
+ return ret;
}
/***********************************************************************
diff --git a/dlls/ntdll/unix/loader.c b/dlls/ntdll/unix/loader.c
index 32aa7267423..3d26da194e4 100644
--- a/dlls/ntdll/unix/loader.c
+++ b/dlls/ntdll/unix/loader.c
@@ -2145,12 +2145,6 @@ static struct unix_funcs unix_funcs =
NtCurrentTeb,
#endif
RtlGetSystemTimePrecise,
- fast_RtlTryAcquireSRWLockExclusive,
- fast_RtlAcquireSRWLockExclusive,
- fast_RtlTryAcquireSRWLockShared,
- fast_RtlAcquireSRWLockShared,
- fast_RtlReleaseSRWLockExclusive,
- fast_RtlReleaseSRWLockShared,
load_so_dll,
init_builtin_dll,
init_unix_lib,
diff --git a/dlls/ntdll/unix/sync.c b/dlls/ntdll/unix/sync.c
index 7a2466f5fa3..0065f265e42 100644
--- a/dlls/ntdll/unix/sync.c
+++ b/dlls/ntdll/unix/sync.c
@@ -110,8 +110,6 @@ static inline ULONGLONG monotonic_counter(void)
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
-#define FUTEX_WAIT_BITSET 9
-#define FUTEX_WAKE_BITSET 10
static int futex_private = 128;
@@ -125,16 +123,6 @@ static inline int futex_wake( const int *addr, int val )
return syscall( __NR_futex, addr, FUTEX_WAKE | futex_private, val, NULL, 0, 0 );
}
-static inline int futex_wait_bitset( const int *addr, int val, struct timespec *timeout, int mask )
-{
- return syscall( __NR_futex, addr, FUTEX_WAIT_BITSET | futex_private, val, timeout, 0, mask );
-}
-
-static inline int futex_wake_bitset( const int *addr, int val, int mask )
-{
- return syscall( __NR_futex, addr, FUTEX_WAKE_BITSET | futex_private, val, NULL, 0, mask );
-}
-
static inline int use_futexes(void)
{
static int supported = -1;
@@ -152,16 +140,6 @@ static inline int use_futexes(void)
return supported;
}
-static int *get_futex(void **ptr)
-{
- if (sizeof(void *) == 8)
- return (int *)((((ULONG_PTR)ptr) + 3) & ~3);
- else if (!(((ULONG_PTR)ptr) & 3))
- return (int *)ptr;
- else
- return NULL;
-}
-
#endif
@@ -2532,289 +2510,3 @@ NTSTATUS WINAPI NtWaitForAlertByThreadId( const void *address, const LARGE_INTEG
}
#endif
-
-#ifdef __linux__
-
-/* Futex-based SRW lock implementation:
- *
- * Since we can rely on the kernel to release all threads and don't need to
- * worry about NtReleaseKeyedEvent(), we can simplify the layout a bit. The
- * layout looks like this:
- *
- * 31 - Exclusive lock bit, set if the resource is owned exclusively.
- * 30-16 - Number of exclusive waiters. Unlike the fallback implementation,
- * this does not include the thread owning the lock, or shared threads
- * waiting on the lock.
- * 15 - Does this lock have any shared waiters? We use this as an
- * optimization to avoid unnecessary FUTEX_WAKE_BITSET calls when
- * releasing an exclusive lock.
- * 14-0 - Number of shared owners. Unlike the fallback implementation, this
- * does not include the number of shared threads waiting on the lock.
- * Thus the state [1, x, >=1] will never occur.
- */
-
-#define SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT 0x80000000
-#define SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK 0x7fff0000
-#define SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_INC 0x00010000
-#define SRWLOCK_FUTEX_SHARED_WAITERS_BIT 0x00008000
-#define SRWLOCK_FUTEX_SHARED_OWNERS_MASK 0x00007fff
-#define SRWLOCK_FUTEX_SHARED_OWNERS_INC 0x00000001
-
-/* Futex bitmasks; these are independent from the bits in the lock itself. */
-#define SRWLOCK_FUTEX_BITSET_EXCLUSIVE 1
-#define SRWLOCK_FUTEX_BITSET_SHARED 2
-
-NTSTATUS CDECL fast_RtlTryAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- int old, new, *futex;
- NTSTATUS ret;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- do
- {
- old = *futex;
-
- if (!(old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT)
- && !(old & SRWLOCK_FUTEX_SHARED_OWNERS_MASK))
- {
- /* Not locked exclusive or shared. We can try to grab it. */
- new = old | SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT;
- ret = STATUS_SUCCESS;
- }
- else
- {
- new = old;
- ret = STATUS_TIMEOUT;
- }
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- return ret;
-}
-
-NTSTATUS CDECL fast_RtlAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- int old, new, *futex;
- BOOLEAN wait;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- /* Atomically increment the exclusive waiter count. */
- do
- {
- old = *futex;
- new = old + SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_INC;
- assert(new & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK);
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- for (;;)
- {
- do
- {
- old = *futex;
-
- if (!(old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT)
- && !(old & SRWLOCK_FUTEX_SHARED_OWNERS_MASK))
- {
- /* Not locked exclusive or shared. We can try to grab it. */
- new = old | SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT;
- assert(old & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK);
- new -= SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_INC;
- wait = FALSE;
- }
- else
- {
- new = old;
- wait = TRUE;
- }
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- if (!wait)
- return STATUS_SUCCESS;
-
- futex_wait_bitset( futex, new, NULL, SRWLOCK_FUTEX_BITSET_EXCLUSIVE );
- }
-
- return STATUS_SUCCESS;
-}
-
-NTSTATUS CDECL fast_RtlTryAcquireSRWLockShared( RTL_SRWLOCK *lock )
-{
- int new, old, *futex;
- NTSTATUS ret;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- do
- {
- old = *futex;
-
- if (!(old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT)
- && !(old & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK))
- {
- /* Not locked exclusive, and no exclusive waiters. We can try to
- * grab it. */
- new = old + SRWLOCK_FUTEX_SHARED_OWNERS_INC;
- assert(new & SRWLOCK_FUTEX_SHARED_OWNERS_MASK);
- ret = STATUS_SUCCESS;
- }
- else
- {
- new = old;
- ret = STATUS_TIMEOUT;
- }
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- return ret;
-}
-
-NTSTATUS CDECL fast_RtlAcquireSRWLockShared( RTL_SRWLOCK *lock )
-{
- int old, new, *futex;
- BOOLEAN wait;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- for (;;)
- {
- do
- {
- old = *futex;
-
- if (!(old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT)
- && !(old & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK))
- {
- /* Not locked exclusive, and no exclusive waiters. We can try
- * to grab it. */
- new = old + SRWLOCK_FUTEX_SHARED_OWNERS_INC;
- assert(new & SRWLOCK_FUTEX_SHARED_OWNERS_MASK);
- wait = FALSE;
- }
- else
- {
- new = old | SRWLOCK_FUTEX_SHARED_WAITERS_BIT;
- wait = TRUE;
- }
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- if (!wait)
- return STATUS_SUCCESS;
-
- futex_wait_bitset( futex, new, NULL, SRWLOCK_FUTEX_BITSET_SHARED );
- }
-
- return STATUS_SUCCESS;
-}
-
-NTSTATUS CDECL fast_RtlReleaseSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- int old, new, *futex;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- do
- {
- old = *futex;
-
- if (!(old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT))
- {
- ERR("Lock %p is not owned exclusive! (%#x)\n", lock, *futex);
- return STATUS_RESOURCE_NOT_OWNED;
- }
-
- new = old & ~SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT;
-
- if (!(new & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK))
- new &= ~SRWLOCK_FUTEX_SHARED_WAITERS_BIT;
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- if (new & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK)
- futex_wake_bitset( futex, 1, SRWLOCK_FUTEX_BITSET_EXCLUSIVE );
- else if (old & SRWLOCK_FUTEX_SHARED_WAITERS_BIT)
- futex_wake_bitset( futex, INT_MAX, SRWLOCK_FUTEX_BITSET_SHARED );
-
- return STATUS_SUCCESS;
-}
-
-NTSTATUS CDECL fast_RtlReleaseSRWLockShared( RTL_SRWLOCK *lock )
-{
- int old, new, *futex;
-
- if (!use_futexes()) return STATUS_NOT_IMPLEMENTED;
-
- if (!(futex = get_futex( &lock->Ptr )))
- return STATUS_NOT_IMPLEMENTED;
-
- do
- {
- old = *futex;
-
- if (old & SRWLOCK_FUTEX_EXCLUSIVE_LOCK_BIT)
- {
- ERR("Lock %p is owned exclusive! (%#x)\n", lock, *futex);
- return STATUS_RESOURCE_NOT_OWNED;
- }
- else if (!(old & SRWLOCK_FUTEX_SHARED_OWNERS_MASK))
- {
- ERR("Lock %p is not owned shared! (%#x)\n", lock, *futex);
- return STATUS_RESOURCE_NOT_OWNED;
- }
-
- new = old - SRWLOCK_FUTEX_SHARED_OWNERS_INC;
- } while (InterlockedCompareExchange( futex, new, old ) != old);
-
- /* Optimization: only bother waking if there are actually exclusive waiters. */
- if (!(new & SRWLOCK_FUTEX_SHARED_OWNERS_MASK) && (new & SRWLOCK_FUTEX_EXCLUSIVE_WAITERS_MASK))
- futex_wake_bitset( futex, 1, SRWLOCK_FUTEX_BITSET_EXCLUSIVE );
-
- return STATUS_SUCCESS;
-}
-
-#else
-
-NTSTATUS CDECL fast_RtlTryAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-NTSTATUS CDECL fast_RtlAcquireSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-NTSTATUS CDECL fast_RtlTryAcquireSRWLockShared( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-NTSTATUS CDECL fast_RtlAcquireSRWLockShared( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-NTSTATUS CDECL fast_RtlReleaseSRWLockExclusive( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-NTSTATUS CDECL fast_RtlReleaseSRWLockShared( RTL_SRWLOCK *lock )
-{
- return STATUS_NOT_IMPLEMENTED;
-}
-
-#endif
diff --git a/dlls/ntdll/unix/unix_private.h b/dlls/ntdll/unix/unix_private.h
index 61f37d4b22f..b499978b2fe 100644
--- a/dlls/ntdll/unix/unix_private.h
+++ b/dlls/ntdll/unix/unix_private.h
@@ -100,12 +100,6 @@ extern void (WINAPI *pLdrInitializeThunk)(CONTEXT*,void**,ULONG_PTR,ULONG_PT
extern void (WINAPI *pRtlUserThreadStart)( PRTL_THREAD_START_ROUTINE entry, void *arg ) DECLSPEC_HIDDEN;
extern void (WINAPI *p__wine_ctrl_routine)(void *) DECLSPEC_HIDDEN;
extern SYSTEM_DLL_INIT_BLOCK *pLdrSystemDllInitBlock DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlTryAcquireSRWLockExclusive( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlAcquireSRWLockExclusive( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlTryAcquireSRWLockShared( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlAcquireSRWLockShared( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlReleaseSRWLockExclusive( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
-extern NTSTATUS CDECL fast_RtlReleaseSRWLockShared( RTL_SRWLOCK *lock ) DECLSPEC_HIDDEN;
extern LONGLONG CDECL fast_RtlGetSystemTimePrecise(void) DECLSPEC_HIDDEN;
extern NTSTATUS CDECL unwind_builtin_dll( ULONG type, struct _DISPATCHER_CONTEXT *dispatch,
diff --git a/dlls/ntdll/unixlib.h b/dlls/ntdll/unixlib.h
index a271bb05da9..803b6a082bb 100644
--- a/dlls/ntdll/unixlib.h
+++ b/dlls/ntdll/unixlib.h
@@ -26,7 +26,7 @@
struct _DISPATCHER_CONTEXT;
/* increment this when you change the function table */
-#define NTDLL_UNIXLIB_VERSION 131
+#define NTDLL_UNIXLIB_VERSION 132
struct unix_funcs
{
@@ -38,14 +38,6 @@ struct unix_funcs
/* other Win32 API functions */
LONGLONG (WINAPI *RtlGetSystemTimePrecise)(void);
- /* fast locks */
- NTSTATUS (CDECL *fast_RtlTryAcquireSRWLockExclusive)( RTL_SRWLOCK *lock );
- NTSTATUS (CDECL *fast_RtlAcquireSRWLockExclusive)( RTL_SRWLOCK *lock );
- NTSTATUS (CDECL *fast_RtlTryAcquireSRWLockShared)( RTL_SRWLOCK *lock );
- NTSTATUS (CDECL *fast_RtlAcquireSRWLockShared)( RTL_SRWLOCK *lock );
- NTSTATUS (CDECL *fast_RtlReleaseSRWLockExclusive)( RTL_SRWLOCK *lock );
- NTSTATUS (CDECL *fast_RtlReleaseSRWLockShared)( RTL_SRWLOCK *lock );
-
/* loader functions */
NTSTATUS (CDECL *load_so_dll)( UNICODE_STRING *nt_name, void **module );
void (CDECL *init_builtin_dll)( void *module );
--
2.33.0
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