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E.2.1.2 Functions and Arguments for the DECchip 21064/21066/21068
The functions execute on a single (the current running) processor only and are described in Table
•The OpenVMS Alpha MTPR_PERFMON instruction is called with a function code in R16, a
•The DIGITAL UNIX wrperfmon instruction is called with a function code in a0, a func- tion specific argument in a1, and status is returned in v0.
•The Windows NT Alpha wrperfmon instruction is called with input parameters a0 through a3, as shown in Table
Table
Function Register Usage | Comments | |
|
| |
Enable performance monitoring | Enable takes effect at the next IPL change | |
|
|
|
DIGITAL UNIX |
|
|
Input: | a0 = 1 | Function code |
| a1 = 0 | Argument |
Output: | v0 = 1 | Success |
| v0 = 0 | Failure (not generated) |
OpenVMS Alpha |
|
|
Input: | R16 = 1 | Function code |
| R17 = 0 | Argument |
Output: | R0 = 1 | Success |
| R0 = 0 | Failure (not generated) |
Windows NT Alpha |
| |
Input: | a0 = 0 | Select counter 0 |
| a0 = 1 | Select counter 1 |
| a1 = 1 | Enable selected counter |
|
| |
Disable performance monitoring | Disable takes effect at the next IPL change | |
|
|
|
DIGITAL UNIX |
|
|
Input: | a0 = 0 | Function code |
| a1 = 0 | Argument |
Output: | v0 = 1 | Success |
| v0 = 0 | Failure (not generated) |
OpenVMS Alpha |
|
|
Input: | R16 = 0 | Function code |
| R17 = 0 | Argument |
Output: | R0 = 1 | Success |
| R0 = 0 | Failure (not generated) |
|
|
|
Waivers and