gtpc2m5a | C/C++ Language Support User's Guide |
This function permits an E-type program to request the control program
establish a uniprocessor (UP) environment or reestablish the multiprocessor
(MP) environment in a system running on a multiple I-stream central processing
complex (CPC). It permits a program that is not capable of executing in
an MP environment to complete its processing in a UP environment.
Format
#include <sysapi.h>
void pausc(enum t_pausc_opt option);
- option
- Either PAUSC_BEGIN or PAUSC_END to turn on or turn off the multiprocessor
environment. The definition of t_pausc_opt is defined in the
sysapi.h header file.
Normal Return
Void.
Error Return
Not applicable.
Programming Considerations
- This function can only be run on the main I-stream.
- Use this function with discretion. Executing in a UP environment
can seriously impact performance on an MP CPC. The time spent in the UP
environment must be kept to a minimum. The number of invocations of
this function must also be kept to a minimum.
- The same ECB must stop and restart the MP environment.
- No memory locks or record holds are permitted while the system is in a UP
environment (paused).
- When requesting a system UP pause, this ECB must not have previously
paused the system. If it has, system error dump CTL-000578 is taken and
control is returned to the program.
- When requesting a system MP restart, this ECB must have previously paused
the system. If not, the entry is exited and a 0005777 system error is
issued.
Examples
#include <sysapi.h>
.
. /* processing in MP mode, main I-stream */
pausc(PAUSC_BEGIN);
.
. /* processing in UP mode */
pausc(PAUSC_END)
.
. /* return to MP mode */
Related Information
None.