int
splraiseipl(
ipl_cookie_t icookie
)
)
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 levels.
)
returns saved priority level which can be used for
splx(
).
s = splraiseipl(makeiplcookie(IPL_VM));
s = splvm();
Because
makeiplcookie(
ourcookie = makeiplcookie(ipl);
}
performance_critical_code()
{
int s;
s = splraiseipl(ourcookie);
do_something();
splx(s);
}
)
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)
{