.TH PMC 2
.SH NAME
confpmc, rdpmc \- access to perfomance counters on this processor
.SH SYNOPSIS
.B #include <u.h>
.br
.B #include <libc.h>
.PP
.B
int confpmc(int core, int index, int mode, char *desc)
.PP
.B
uvlong rdpmc(int index)
.SH DESCRIPTION
.I Confpmc
configures the counter
.I index
on core
.I core
setting the configuration according to the configuration string,
.I desc
whic is architecture dependant and the
.I mode,
which can be an OR of three values:
.TP
.BR PmcOs
the counter only counts while in kernel space,
.TP
.BR PmcUser
the counter only counts while in user space,
.TP
.BR PmcEnable
enables the counter.
.PP
.I Rdpmc
reads the counter
.I index
if possible using special instructions or mapped memory and defaulting
to reading the corresponding file if unavailable.
.SH SOURCE
.B /sys/src/libc/amd64/rdpmc.s
.br
.B /sys/src/libc/port/confpmc.c
.br
.B /sys/src/libc/port/rdpmc.c
.SH SEE ALSO
.IR pmc (3)