netbsd man page for splraiseipl

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);

DESCRIPTION
     splraiseipl() 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.

RETURN VALUES
     splraiseipl() 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 ALSO
     condvar(9), makeiplcookie(9), mutex(9), rwlock(9), spl(9)

BSD
								 February 11, 2007							       BSD