Specifications

Operating System Routines

EXE$DEBIT_BYTCNT_ALO, EXE$DEBIT_BYTCNT_BYTLM_ALO

Synchronization

EXE$DEBIT_BYTCNT_ALO and EXE$DEBIT_BYTCNT_BYTLM_ALO raise IPL

to IPL$_SYNCH and obtain the JIB spinlock in a multiprocessing environment.

Their callers cannot be executing above IPL$_SYNCH or hold any spinlock.

EXE$DEBIT_BYTCNT_ALO and EXE$DEBIT_BYTCNT_BYTLM_ALO return

control to their callers at IPL$_ASTDEL.

Description

EXE$DEBIT_BYTCNT_ALO checks whether a process has sufﬁcient quota for

a buffer of the speciﬁed size and, if so, allocates the buffer from nonpaged pool

and deducts the corresponding number of bytes from the job’s byte count quota.

EXE$DEBIT_BYTCNT_BYTLM_ALO also adjusts the job’s byte limit. Both

routines round the value speciﬁed in R1 up to the nearest 16-byte boundary

before applying it to the JIB.

If there is insufﬁcient nonpaged pool available for the buffer, these routines

return SS$_INSFMEM status to the caller.

If the process’s quota usage is too large, EXE$DEBIT_BYTCNT_ALO and

EXE$DEBIT_BYTCNT_BYTLM_ALO place the process into a resource wait state,

based on the setting of PCB$V_SSRWAIT, until sufﬁcient quota is returned to the

job.

If bit 31 in R1 is clear, these routines compare the byte count in R1 against

IOC$GW_MAXBUF, returning an error if the system’s maximum buffer allotment

to a process is exceeded.

3–27