man-pages/man3/__ppc_set_ppr_med.3

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.TH __PPC_SET_PPR_MED 3 2015-08-05 "GNU C Library" "Linux\
Programmer's Manual"
.SH NAME
__ppc_set_ppr_med, __ppc_set_ppr_low, __ppc_set_ppr_med_low \-
Set the Program Priority Register
.SH SYNOPSIS
.B #include <sys/platform/ppc.h>
.sp
.B void __ppc_set_ppr_med(void);
.br
.B void __ppc_set_ppr_low(void);
.br
.B void __ppc_set_ppr_med_low(void);
.SH DESCRIPTION
These functions provide access to the
.I Program Priority Register
(PPR) on the Power architecture.
.P
The PPR is a 64-bit register that controls the program's priority.
By adjusting the PPR value the programmer may improve system
throughput by causing system resources to be used more
efficiently, especially in contention situations.
The three unprivileged states available are covered by the following functions:
.IP * 3
.BR __ppc_set_ppr_med ()
sets the Program Priority Register value to
.IR medium
(default).
.IP *
.BR __ppc_set_ppr_low ()
sets the Program Priority Register value to
.IR low .
.IP *
.BR __ppc_set_ppr_med_low ()
sets the Program Priority Register value to
.IR "medium low" .
.SH VERSIONS
These functions first appeared in glibc in version 2.18.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.TS
allbox;
lb lb lb
l l l.
Interface	Attribute	Value
T{
.BR __ppc_set_ppr_med (),
.BR __ppc_set_ppr_low (),
.BR __ppc_set_ppr_med_low ()
T}	Thread safety	MT-Safe
.TE
.ad
.SH CONFORMING TO
These functions are nonstandard GNU extensions.
.SH SEE ALSO
.BR __ppc_yield (3)

.IR "Power ISA, Book\ II - Section\ 3.1 (Program Priority Registers)"