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NF:ndis.NdisAcquireSpinLock

NdisAcquireSpinLock macro (ndis.h)

The NdisAcquireSpinLock function acquires a spin lock so the caller gains exclusive access to the resources, shared among driver functions, that the spin lock protects.

netvista\ndisacquirespinlock.htm

netvista

05/02/2018

NdisAcquireSpinLock macro

NdisAcquireSpinLock, NdisAcquireSpinLock macro [Network Drivers Starting with Windows Vista], ndis/NdisAcquireSpinLock, ndis_spin_lock_ref_54c55d32-a190-4454-ad0d-670427754b8b.xml, netvista.ndisacquirespinlock

ndis.h

Ndis.h

Universal

Supported for NDIS 6.0 and NDIS 5.1 drivers (see NdisAcquireSpinLock (NDIS 5.1)) in Windows Vista. Supported for NDIS 5.1 drivers (see NdisAcquireSpinLock (NDIS 5.1)) in Windows XP.

Irql_Synch_Function, SpinLock, SpinLockBalanced, SpinLockDpr, SpinLockDprRelease, SpinlockRelease

Ndis.lib

<= DISPATCH_LEVEL

Windows

NdisAcquireSpinLock

ndis/NdisAcquireSpinLock

APIRef

kbSyntax

LibDef

ndis.lib

ndis.dll

NdisAcquireSpinLock

NdisAcquireSpinLock macro

-description

The NdisAcquireSpinLock function acquires a spin lock so the caller gains exclusive access to the resources, shared among driver functions, that the spin lock protects.

-parameters

-param _SpinLock [in]

Pointer to an opaque spin lock, already initialized by the caller.

-remarks

The driver must initialize a variable of type NDIS_SPIN_LOCK with NdisAllocateSpinLock before it calls any other NdisXxxSpinLock function. The driver must provide resident storage for the spin lock(s) it uses.

After acquiring a spin lock with NdisAcquireSpinLock, the caller must release that lock with a call to NdisReleaseSpinLock. A driver must call NdisReleaseSpinLock following each call to NdisAcquireSpinLock. Otherwise, a deadlock occurs, hanging the driver.

A spin lock acquired with NdisAcquireSpinLock must be released with NdisReleaseSpinLock. A spin lock acquired with NdisDprAcquireSpinLock must be released with NdisDprReleaseSpinLock.

A driver should never hold a spin lock for an extended period (more than a few instructions). Holding a spin lock for longer than 25 microseconds degrades both system and driver performance.

A miniport driver cannot use a spin lock to protect resources that its other functions share with the MiniportInterrupt and/or MiniportDisableInterruptEx functions. Instead, a miniport driver must call NdisMSynchronizeWithInterruptEx so that its MiniportSynchronizeInterrupt function accesses such shared resources at the same DIRQL at which its
MiniportInterrupt and/or MiniportDisableInterruptEx functions do.