1.\" $NetBSD: splraiseipl.9,v 1.9 2018/02/08 09:03:23 dholland Exp $ 2.\" 3.\" Copyright (c)2006 YAMAMOTO Takashi, 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" ------------------------------------------------------------ 28.Dd July 9, 2015 29.Dt SPLRAISEIPL 9 30.Os 31.\" ------------------------------------------------------------ 32.Sh NAME 33.Nm splraiseipl 34.Nd raise the system priority level 35.\" ------------------------------------------------------------ 36.Sh SYNOPSIS 37.In sys/intr.h 38.\" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 39.Ft int 40.Fn splraiseipl \ 41"ipl_cookie_t icookie" 42.\" ------------------------------------------------------------ 43.Sh DESCRIPTION 44.Fn splraiseipl 45raises the system priority level to the level specified by 46.Fa icookie . 47.Fa icookie 48should be a value returned by 49.Fn makeiplcookie . 50.Pp 51In general, device drivers should not make use of this interface. 52To ensure correct synchronization, device drivers should use the 53.Xr condvar 9 , 54.Xr mutex 9 , 55and 56.Xr rwlock 9 57interfaces. 58.Pp 59See the 60.Xr spl 9 61manual page for a description of interrupt priority levels. 62.\" ------------------------------------------------------------ 63.Sh RETURN VALUES 64.Fn splraiseipl 65returns saved priority level which can be used for 66.Fn splx . 67.\" ------------------------------------------------------------ 68.Sh EXAMPLES 69The following two lines are functional equivalents. 70.Bd -literal 71 s = splraiseipl(makeiplcookie(IPL_VM)); 72.Ed 73.Bd -literal 74 s = splvm(); 75.Ed 76.Pp 77Because 78.Fn makeiplcookie 79can be slow and is not expected to be used in a performance critical path, 80it's better to do it beforehand. 81.Bd -literal 82 initialization_code(ipl_t ipl) 83 { 84 85 ourcookie = makeiplcookie(ipl); 86 } 87 88 performance_critical_code() 89 { 90 int s; 91 92 s = splraiseipl(ourcookie); 93 do_something(); 94 splx(s); 95 } 96.Ed 97.\" ------------------------------------------------------------ 98.Sh SEE ALSO 99.Xr condvar 9 , 100.Xr makeiplcookie 9 , 101.Xr mutex 9 , 102.Xr rwlock 9 , 103.Xr spl 9 104