Parameters

The parameters are explained as follows:

name

An optional symbol, starting in column 1, that is the name on the IWMCNTN macro invocation. The name must conform to the rules for an ordinary assembler language symbol.

,INVOCATIONTYPE=UPDATE

,INVOCATIONTYPE=REPLACE

,INVOCATIONTYPE=ENDOFCONTENTION

A required parameter, which indicates the type of operation requested

,INVOCATIONTYPE=UPDATE

indicates that the operations described in the request list have to be applied to the resource. If contention information for the resource does not already exist, it is created. If after applying the operations there are no holders or waiters (local or remote), tracking of the resource is abandoned locally.

,INVOCATIONTYPE=REPLACE

same as UPDATE, except that any existing local resource topology is discarded first.

,INVOCATIONTYPE=ENDOFCONTENTION

indicates that all topology information for the resource is discarded.

,MF=S

,MF=(L,list addr)

,MF=(L,list addr,attr)

,MF=(L,list addr,0D)

,MF=(E,list addr)

,MF=(E,list addr,COMPLETE)

An optional input parameter that specifies the macro form.

Use MF=S to specify the standard form of the macro, which builds an inline parameter list and generates the macro invocation to transfer control to the service. MF=S is the default.

Use MF=L to specify the list form of the macro. Use the list form together with the execute form of the macro for applications that require reentrant code. The list form defines an area of storage that the execute form uses to store the parameters. Only the PLISTVER parameter may be coded with the list form of the macro.

Use MF=E to specify the execute form of the macro. Use the execute form together with the list form of the macro for applications that require reentrant code. The execute form of the macro stores the parameters into the storage area defined by the list form, and generates the macro invocation to transfer control to the service.

,list addr

The name of a storage area to contain the parameters. For MF=S and MF=E, this can be an RS-type address or an address in register (1)-(12).

,attr

An optional 1- to 60-character input string that you use to force boundary alignment of the parameter list. Use a value of 0F to force the parameter list to a word boundary, or 0D to force the parameter list to a doubleword boundary. If you do not code attr, the system provides a value of 0D.

,COMPLETE

Specifies that the system is to check for required parameters and supply defaults for omitted optional parameters.

,PLISTVER=IMPLIED_VERSION

,PLISTVER=MAX

,PLISTVER=0

An optional input parameter that specifies the version of the macro. PLISTVER determines which parameter list the system generates. PLISTVER is an optional input parameter on all forms of the macro, including the list form. When using PLISTVER, specify it on all macro forms used for a request and with the same value on all of the macro forms. The values are:

• IMPLIED_VERSION, which is the lowest version that allows all parameters specified on the request to be processed. If you omit the PLISTVER parameter, IMPLIED_VERSION is the default.
• MAX, if you want the parameter list to be the largest size currently possible. This size might grow from release to release and affect the amount of storage that your program needs.

  If you can tolerate the size change, IBM® recommends that you always specify PLISTVER=MAX on the list form of the macro. Specifying MAX ensures that the list-form parameter list is always long enough to hold all the parameters you might specify on the execute form, when both are assembled with the same level of the system. In this way, MAX ensures that the parameter list does not overwrite nearby storage.

• 0, if you use the currently available parameters.

To code: Specify one of the following:

• IMPLIED_VERSION
• MAX
• A decimal value of 0

,REQUESTLIST=requestlist

When INVOCATIONTYPE=UPDATE or REPLACE is specified, a required input parameter, which specifies a list of topology requests. For each request, you must specify:

• Whether you want to add or to delete the contention information
• Whether the work unit is holding the resource or is waiting for it,
• The identification of the entity in terms of STOKEN, TCB address or enclave token.

For each request the macro returns a return and a reason code. See IWMCNTRL for the mapping of the request list.

The work unit ID varies based on the resource ownership model (transaction or task resource) used by the IWMCNTN exploiter and the work unit type involved, as described in Table 22:

Table 22. Work unit IDs

Work unit type	Exploiters using the transaction model will pass	Exploiters using the task resource model will pass
Global SRB, local SRB, preemptible SRB (but not a client or enclave SRB)	Home STOKEN, TCB=0, Etoken=0	Same as transaction resource ownership model
Client SRB	Client STOKEN TCB=0, Etoken=0	Same as transaction resource ownership model
Enclave SRB	STOKEN=0, TCB=0, Etoken=e	Same as transaction resource ownership model
Non-enclave task	Home STOKEN, TCB= 0, Etoken=0	Home STOKEN, TCB= t, Etoken=0
Enclave task	STOKEN=0, TCB= 0, Etoken=e	Home STOKEN, TCB= t, Etoken=0

The following return/reason codes may be returned per request:

Return_Code

A 2-byte output field set based on whether or not the entity identification information passed validity checks.

0

Name: IwmRetCodeOk Meaning: Successful completion. Action: None required.

4

Name: IwmRetCodeWarning Meaning: Successful completion, unusual conditions noted. Action: Check reason code

8

Name: IwmRetCodeInvocError Meaning: Invalid invocation environment or parameters. Action: Check reason code

Reason_Code

A 2-byte output field set based on whether or not the entity identification information passed validity checks.

0448

Name: IwmRsnCodePossibleDeadlock Meaning: The specified chronic resource contention may have caused a deadlock: The holder of resource (A) is waiting for resource (B), which is currently held by another holder, which is waiting for resource (A). Action: Check for possible deadlock.

0807

Name: IwmRsnCodeBadSTOKEN Meaning: The specified STOKEN does not pass verification. Action: Check for possible storage overlay of the address space token.

083A

Name: IwmRsnCodeBadEnclave Meaning: Enclave token does not pass verification. Action: Check for possible storage overlay of the enclave token.

0886

Name: IwmRsnCodeBadRequestCode Meaning: The request code must be either ADD or DELETE Action: Correct the request code.

0887

Name: IwmRsnCodeBadEntityType Meaning: The entity type must be either HOLDER or WAITER Action: Correct the entity type.

088A

Name: IwmRsnCodeBadEntityId Meaning: The specified combination of STOKEN, TCB and/or enclave token does not pass verification. Action: Correct the entity id.

088B

Name: IwmRsnCodeBadTCB Meaning: The specified TCB address does not pass verification. Action: Correct the TCB address. Task may have terminated since the parameter list was built. TCB may not match STOKEN.

08A5

Name: IwmRsnCodeNoContention Meaning: The specified chronic resource contention is not stored in the topology. The DELETE request for this request list entry was not processed. Action: Correct the delete request.

08A8

Name: IwmRsnCodeDupContention Meaning: The specified chronic resource contention is already stored in the topology. The ADD request for this request list entry was not processed. Action: Correct the add request.

08AF

Name: IwmRsnCodeDeadlock Meaning: The specified chronic resource contention caused a deadlock:
The holder of resource (A) is waiting for resource (B), which is currently held by another holder, which is waiting for resource (A). The request list entry was not processed. Action: Remove the deadlock.

To code: Specify the RS-type address, or address in register (2)-(12), of a character field.

,RESOURCEID=resourceid

A required input parameter, which identifies the resource uniquely within all resources for a subsystem type and name.

For resources whose type is multisystem, the value must be unique within the subsystem type and name across all systems where the interface might ever be invoked for this resource.

To code: Specify the RS-type address, or address in register (2)-(12), of a character field.

,RESOURCEID_LEN=resourceid_len

A required input parameter, which contains the length of the resource identifier. A resource identifier may not exceed 264 bytes.

To code: Specify the RS-type address, or address in register (2)-(12), of a fullword field.

,RESOURCESCOPE=SINGLESYSTEM

,RESOURCESCOPE=MULTISYSTEM

An optional parameter, which identifies if the resource information is shared with other WLM instances in the cluster. The default is RESOURCESCOPE=SINGLESYSTEM.

,RESOURCESCOPE=SINGLESYSTEM

indicates that the resource information is used on the issuing system only.

,RESOURCESCOPE=MULTISYSTEM

indicates that the resource information is shared among other systems.

,RETCODE=retcode

An optional output parameter into which the return code is to be copied from GPR 15.

To code: Specify the RS-type address of a fullword field, or register (2)-(12).

,RSNCODE=rsncode

An optional output parameter into which the reason code is to be copied from GPR 0.

To code: Specify the RS-type address of a fullword field, or register (2)-(12).

SUBSYS=subsys

A required input parameter, which contains the generic subsystem type (e.g. IMS™, CICS®, etc.).

To code: Specify the RS-type address, or address in register (2)-(12), of a 4-character field.

,SUBSYSNM=subsysnm

A required input parameter, which identifies the subsystem instance.

To code: Specify the RS-type address, or address in register (2)-(12), of an 8-character field.