PERFMONCTL

NAME

SYNOPSIS

#include <syscall.h>
#include <perfmon.h>

long perfmonctl(int fd, int cmd, void *arg, int narg);

DESCRIPTION

perfmonctl will apply a function cmd to input arguments arg. The number of arguments is defined by input variable narg. fd specifies the perfmon context to operate on.

The implemented commands cmd are:

PFM_CREATE_CONTEXT     

set up a context

perfmonctl(int fd, PFM_CREATE_CONTEXT , pfarg_context_t *ctxt, 1);

The fd parameter is ignored. A new context is created as specified in ctxt and its file descriptor is returned in ctxt->ctx_fd.

The file descriptor, apart from passing it to perfmonctl, can be used to read event notifications (type pfm_msg_t) using the read(2) system call. Both select(2) and poll(2) can be used to wait for event notifications.

The context can be destroyed using the close(2) system call.

PFM_WRITE_PMCS

set PMC registers

perfmonctl(int fd, PFM_WRITE_PMCS , pfarg_pmc_t *pmcs, n);

PFM_WRITE_PMDS        

set PMD registers

perfmonctl(int fd, PFM_WRITE_PMDS , pfarg_pmd_t *pmds, n);

PFM_READ_PMDS  

read PMD registers

perfmonctl(int fd, PFM_READ_PMDS , pfarg_pmd_t *pmds, n);

PFM_START      

start monitoring

perfmonctl(int fd, PFM_START , arg , 1);
perfmonctl(int fd, PFM_START , NULL , 0);

PFM_STOP       

stop monitoring

perfmonctl(int fd, PFM_START , NULL , 0);

PFM_LOAD_CONTEXT       

attach the context to a thread

perfmonctl(int fd, PFM_LOAD_CONTEXT ,pfarg_load_t *largs,1);

PFM_UNLOAD_CONTEXT     

detach the context from a thread

perfmonctl(int fd, PFM_UNLOAD_CONTEXT , NULL , 0);

PFM_RESTART    

restart monitoring after recieving an overflow notification

perfmonctl(int fd, PFM_RESTART , NULL , 0);

PFM_CREATE_EVTSETS     

create or modify event sets

perfmonctl(int fd, PFM_CREATE_EVTSETS, pfarg_setdesc_t *desc , n);

PFM_DELETE_EVTSETS     

delete event sets

perfmonctl(int fd, PFM_DELETE_EVTSET, pfarg_setdesc_t *desc , n);

PFM_GETINFO_EVTSETS    

get information about event sets

perfmonctl(int fd, PFM_GETINFO_EVTSETS, pfarg_setinfo_t *info, n);

RETURN VALUE

AVAILABILITY

SEE ALSO