perfmonctl — interface to IA-64 performance monitoring unit
#include <syscall.h> #include <perfmon.h>
long
perfmonctl( |
int fd, |
| int cmd, | |
| void *arg, | |
int narg); |
![]() |
Note |
|---|---|
| There is no glibc wrapper for this system call; see NOTES. |
The IA-64-specific perfmonctl() system call provides an
interface to the PMU (performance monitoring unit). The PMU
consists of PMD (performance monitoring data) registers and
PMC (performance monitoring control) registers, which gather
hardware statistics.
perfmonctl() applies the
operation cmd to the
input arguments specified by arg. The number of arguments is
defined by narg. The
fd argument specifies
the perfmon context to operate on.
Supported values for cmd are:
PFM_CREATE_CONTEXTperfmonctl(int fd,PFM_CREATE_CONTEXT,pfarg_context_t *ctxt,1);
Set up a context.
The fd
parameter is ignored. A new perfmon context is created
as specified in ctxt and its file
descriptor is returned in ctxt->ctx_fd.
The file descriptor can be used in subsequent calls
to perfmonctl() and can
be used to read event notifications (type pfm_msg_t) using read(2). The file
descriptor is pollable using select(2), poll(2), and
epoll(7).
The context can be destroyed by calling close(2) on the file descriptor.
PFM_WRITE_PMCSperfmonctl(int fd,PFM_WRITE_PMCS,pfarg_reg_t *pmcs,n);
Set PMC registers.
PFM_WRITE_PMDSperfmonctl(int fd,PFM_WRITE_PMDS,pfarg_reg_t *pmds,n);
Set PMD registers.
PFM_READ_PMDSperfmonctl(int fd,PFM_READ_PMDS,pfarg_reg_t *pmds,n);
Read PMD registers.
PFM_STARTperfmonctl(int fd,PFM_START,NULL,0);
Start monitoring.
PFM_STOPperfmonctl(int fd,PFM_STOP,NULL,0);
Stop monitoring.
PFM_LOAD_CONTEXTperfmonctl(int fd,PFM_LOAD_CONTEXT,pfarg_load_t *largs,1);
Attach the context to a thread.
PFM_UNLOAD_CONTEXTperfmonctl(int fd,PFM_UNLOAD_CONTEXT,NULL,0);
Detach the context from a thread.
PFM_RESTARTperfmonctl(int fd,PFM_RESTART,NULL,0);
Restart monitoring after receiving an overflow notification.
PFM_GET_FEATURESperfmonctl(int fd,PFM_GET_FEARURES,pfarg_features_t *arg,1);
PFM_DEBUGperfmonctl(int fd,PFM_DEBUG,val,0);
If val is
nonzero, enable debugging mode, otherwise disable.
PFM_GET_PMC_RESET_VALperfmonctl(int fd,PFM_GET_PMC_RESET_VAL,pfarg_reg_t * req,n);
Reset PMC registers to default values.
perfmonctl() returns zero
when the operation is successful. On error, −1 is
returned and errno is set to
indicate the cause of the error.
This page is part of release 3.72 of the Linux man-pages project. A
description of the project, information about reporting bugs,
and the latest version of this page, can be found at
http://www.kernel.org/doc/man−pages/.
|
Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. and Copyright (C) 2013 Michael Kerrisk <mtk.manpagesgmail.com> Written by Ivana Varekova <varekovaredhat.com> %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. %%%LICENSE_END |