Shared memory has to conform to the following specification. Padding is
added between certain elements in shared memory if cache alignment is
required for the region in which the instance is placed.
const GatePeterson.Q_BLOCKING |
 |
Blocking quality
XDCscript usage |
meta-domain |
const GatePeterson.Q_BLOCKING = 1;
#define GatePeterson_Q_BLOCKING (Int)1
DETAILS
Gates with this "quality" may cause the calling thread to block;
i.e., suspend execution until another thread leaves the gate.
const GatePeterson.Q_PREEMPTING |
 |
Preempting quality
XDCscript usage |
meta-domain |
const GatePeterson.Q_PREEMPTING = 2;
#define GatePeterson_Q_PREEMPTING (Int)2
DETAILS
Gates with this "quality" allow other threads to preempt the thread
that has already entered the gate.
enum GatePeterson.LocalProtect |
 |
Local protection enum
XDCscript usage |
meta-domain |
values of type GatePeterson.LocalProtect
const GatePeterson.LocalProtect_NONE;
const GatePeterson.LocalProtect_INTERRUPT;
const GatePeterson.LocalProtect_TASKLET;
const GatePeterson.LocalProtect_THREAD;
const GatePeterson.LocalProtect_PROCESS;
typedef enum GatePeterson_LocalProtect {
GatePeterson_LocalProtect_NONE,
GatePeterson_LocalProtect_INTERRUPT,
GatePeterson_LocalProtect_TASKLET,
GatePeterson_LocalProtect_THREAD,
GatePeterson_LocalProtect_PROCESS
} GatePeterson_LocalProtect;
DETAILS
Must be the same GateMP.
config GatePeterson.E_gateRemotelyOpened // module-wide |
 |
Error raised when gate cannot be opened because of the opener's ID
XDCscript usage |
meta-domain |
msg: "E_gateRemotelyOpened: Gate already in use by two other processors: creator: %d, opener: %d"
};
extern const Error_Id GatePeterson_E_gateRemotelyOpened;
DETAILS
Error raised in
open when trying to remotely open a
GatePeterson instance whose configured opener processor Id does
not match that of the opener's MultiProc id. but it has already been
opened/created on two other processors. GatePeterson only works with
two processors.
config GatePeterson.numInstances // module-wide |
 |
Maximum number of instances supported by the GatePeterson module
XDCscript usage |
meta-domain |
GatePeterson.numInstances = UInt 16;
extern const UInt GatePeterson_numInstances;
metaonly config GatePeterson.common$ // module-wide |
 |
Common module configuration parameters
XDCscript usage |
meta-domain |
DETAILS
All modules have this configuration parameter. Its name
contains the '$' character to ensure it does not conflict with
configuration parameters declared by the module. This allows
new configuration parameters to be added in the future without
any chance of breaking existing modules.
GatePeterson.query( ) // module-wide |
 |
Runtime test for a particular gate quality
Bool GatePeterson_query( Int qual );
ARGUMENTS
qual
constant describing a quality
RETURNS
Returns TRUE if the gate has the given quality,
and FALSE otherwise, which includes the case when the gate does not
recognize the constant describing the quality.
GatePeterson.sharedMemReq( ) // module-wide |
 |
Amount of shared memory required for creation of each instance
ARGUMENTS
params
Pointer to the parameters that will be used in
the create.
DETAILS
The value returned by this function may depend on the cache alignment
requirements for the shared region from which memory will be used.
RETURNS
Number of MAUs needed to create the instance.
metaonly GatePeterson.getNumResources( ) // module-wide |
 |
Number of gates instance within the module
XDCscript usage |
meta-domain |
GatePeterson.getNumResources( ) returns UInt
metaonly GatePeterson.queryMeta( ) // module-wide |
 |
Configuration time test for a particular gate quality
XDCscript usage |
meta-domain |
GatePeterson.queryMeta( Int qual ) returns Bool
ARGUMENTS
qual
constant describing a quality
RETURNS
Returns TRUE if the gate has the given quality,
and FALSE otherwise, which includes the case when the gate does not
recognize the constant describing the quality.
module-wide built-ins |
 |
// Get this module's unique id
Bool GatePeterson_Module_startupDone( );
// Test if this module has completed startup
// The heap from which this module allocates memory
Bool GatePeterson_Module_hasMask( );
// Test whether this module has a diagnostics mask
Bits16 GatePeterson_Module_getMask( );
// Returns the diagnostics mask for this module
Void GatePeterson_Module_setMask( Bits16 mask );
// Set the diagnostics mask for this module
per-instance object types |
 |
typedef struct GatePeterson_Object GatePeterson_Object;
// Opaque internal representation of an instance object
// Client reference to an instance object
typedef struct GatePeterson_Struct GatePeterson_Struct;
// Opaque client structure large enough to hold an instance object
// Convert this instance structure pointer into an instance handle
// Convert this instance handle into an instance structure pointer
per-instance config parameters |
 |
XDCscript usage |
meta-domain |
var params = new GatePeterson.Params;
// Instance config-params object
params.openFlag = Bool false;
//
params.regionId = UInt16 0;
//
params.resourceId = UInt 0;
// Logical resource id
params.sharedAddr = Ptr null;
// Physical address of the shared memory
typedef struct GatePeterson_Params {
// Instance config-params structure
// Common per-instance configs
Bool openFlag;
//
UInt16 regionId;
//
UInt resourceId;
// Logical resource id
Ptr sharedAddr;
// Physical address of the shared memory
} GatePeterson_Params;
// Initialize this config-params structure with supplier-specified defaults before instance creation
config GatePeterson.resourceId // per-instance |
 |
Logical resource id
XDCscript usage |
meta-domain |
var params = new GatePeterson.Params;
...
params.resourceId = UInt 0;
config GatePeterson.sharedAddr // per-instance |
 |
Physical address of the shared memory
XDCscript usage |
meta-domain |
var params = new GatePeterson.Params;
...
params.sharedAddr = Ptr null;
DETAILS
The creator must supply the shared memory that will be used
for maintaining shared state information. This parameter is used
only when
Type is set to
Type_SHARED
per-instance creation |
 |
XDCscript usage |
meta-domain |
var params =
new GatePeterson.
Params;
// Allocate instance config-params
params.config = ...
// Assign individual configs
// Create an instance-object
// Allocate and initialize a new instance object and return its handle
// Initialize a new instance object inside the provided structure
ARGUMENTS
params
per-instance config params, or NULL to select default values (target-domain only)
eb
active error-handling block, or NULL to select default policy (target-domain only)
per-instance deletion |
 |
// Finalize and free this previously allocated instance object, setting the referenced handle to NULL
// Finalize the instance object inside the provided structure
GatePeterson.enter( ) // per-instance |
 |
Enter this gate
ARGUMENTS
handle
handle of a previously-created GatePeterson instance object
DETAILS
Each gate provider can implement mutual exclusion using different
algorithms; e.g., disabling all scheduling, disabling the scheduling
of all threads below a specified "priority level", suspending the
caller when the gate has been entered by another thread and
re-enabling it when the the other thread leaves the gate. However,
in all cases, after this method returns that caller has exclusive
access to the data protected by this gate.
A thread may reenter a gate without blocking or failing.
RETURNS
Returns a "key" that is used to
leave this gate; this
value is used to restore thread preemption to the state that
existed just prior to entering this gate.
GatePeterson.leave( ) // per-instance |
 |
Leave this gate
ARGUMENTS
handle
handle of a previously-created GatePeterson instance object
key
the value returned by a matching call to
enter
DETAILS
This method is only called by threads that have previously entered
this gate via
enter. After this method returns, the
caller must not access the data structure protected by this gate
(unless the caller has entered the gate more than once and other
calls to
leave remain to balance the number of previous
calls to
enter).
per-instance convertors |
 |
// unconditionally move one level up the inheritance hierarchy
// conditionally move one level down the inheritance hierarchy; NULL upon failure
// unconditionally move 2 levels up the inheritance hierarchy
// conditionally move 2 levels down the inheritance hierarchy; NULL upon failure
per-instance built-ins |
 |
Int GatePeterson_Object_count( );
// The number of statically-created instance objects
// The handle of the i-th statically-created instance object (array == NULL)
// The handle of the first dynamically-created instance object, or NULL
// The handle of the next dynamically-created instance object, or NULL
// The heap used to allocate dynamically-created instance objects
// The label associated with this instance object
// The name of this instance object