SPLRAISEIPL(9) BSD Kernel Developer's Manual SPLRAISEIPL(9)NAME
splraiseipl — raise the system priority level
SYNOPSIS
#include <sys/param.h>
int
splraiseipl(ipl_cookie_t icookie);
DESCRIPTIONsplraiseipl() raises the system priority level to the level specified by
icookie. icookie should be a value returned by makeiplcookie().
In general, device drivers should not make use of this interface. To
ensure correct synchronization, device drivers should use the condvar(9),
mutex(9), and rwlock(9) interfaces.
See the spl(9) manual page for a description of interrupt priority lev‐
els.
RETURN VALUESsplraiseipl() returns saved priority level which can be used for splx().
EXAMPLES
The following two lines are functional equivalents.
s = splraiseipl(makeiplcookie(IPL_VM));
s = splvm();
Because makeiplcookie() can be slow and is not expected to be used in a
perfomance critical path, it's better to do it beforehand.
initialization_code(ipl_t ipl)
{
ourcookie = makeiplcookie(ipl);
}
performance_critical_code()
{
int s;
s = splraiseipl(ourcookie);
do_something();
splx(s);
}
SEE ALSOcondvar(9), makeiplcookie(9), mutex(9), rwlock(9), spl(9)BSD February 11, 2007 BSD