1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 23 /* All Rights Reserved */ 24 /* Copyright (c) 1994 Sun Microsystems, Inc. */ 25 26 27 #pragma ident "%Z%%M% %I% %E% SMI" /* from SVr4.0 1.15 */ 28 29 #include <sys/types.h> 30 #include <sys/param.h> 31 #include <sys/sysmacros.h> 32 #include <sys/systm.h> 33 #include <sys/errno.h> 34 #include <sys/cred.h> 35 #include <sys/proc.h> 36 #include <sys/debug.h> 37 #include <sys/class.h> 38 #include <sys/mutex.h> 39 40 /* 41 * We support the nice system call for compatibility although 42 * the priocntl system call supports a superset of nice's functionality. 43 * We support nice only for time sharing threads. It will fail 44 * if called by a thread from another class. 45 */ 46 47 int 48 nice(int niceness) 49 { 50 int error = 0; 51 int err, retval; 52 kthread_id_t t; 53 proc_t *p = curproc; 54 55 mutex_enter(&p->p_lock); 56 t = p->p_tlist; 57 do { 58 err = CL_DONICE(t, CRED(), niceness, &retval); 59 if (error == 0 && err) 60 error = set_errno(err); 61 } while ((t = t->t_forw) != p->p_tlist); 62 mutex_exit(&p->p_lock); 63 if (error) 64 return (error); 65 return (retval); 66 } 67