Copyright (c)2007 YAMAMOTO Takashi,
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.Dd April 20, 2007 .Dt CPU_IDLE 9 .Os ------------------------------------------------------------
.Sh NAME .Nm cpu_idle .Nd machine-dependent processor idling interface ------------------------------------------------------------
.Sh SYNOPSIS n sys/cpu.h - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.Ft void .Fn cpu_idle \ "void" ------------------------------------------------------------
.Sh DESCRIPTION .Fn cpu_idle is called by machine-independent code when the processor has nothing to do. It can be used to conserve the processor power, for example.
p .Fn cpu_idle returns immediately if .Fn cpu_need_resched has been called for the processor after the last call of .Fn cpu_idle or .Fn cpu_did_resched on the processor. .Fn cpu_idle returns as soon as possible when .Fn cpu_need_resched is called for the processor. Otherwise, it returns whenever it likes.
p
.Fn cpu_idle
is called at
.Dv IPL_NONE ,
without any locks held.
------------------------------------------------------------
.Sh EXAMPLES
The simplest (and, in some cases, the best) implementation of
.Fn cpu_idle
is the following.
d -literal void
cpu_idle(void)
{
/* nothing */
}
.Ed
------------------------------------------------------------
.Sh SEE ALSO
.Xr cpu_need_resched 9 ,
.Xr cpu_switchto 9 ,
.Xr intro 9 ,
.Xr spl 9
Indexes created Sat Sep 20 22:09:52 GMT 2025