1 /* $NetBSD: userret.h,v 1.26 2013/04/07 07:54:53 kiyohara Exp $ */
2
3 /*-
4 * Copyright (c) 1998, 2000, 2003, 2006, 2008 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Charles M. Hannum, and Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*-
33 * Copyright (c) 1990 The Regents of the University of California.
34 * All rights reserved.
35 *
36 * This code is derived from software contributed to Berkeley by
37 * William Jolitz.
38 *
39 * Redistribution and use in source and binary forms, with or without
40 * modification, are permitted provided that the following conditions
41 * are met:
42 * 1. Redistributions of source code must retain the above copyright
43 * notice, this list of conditions and the following disclaimer.
44 * 2. Redistributions in binary form must reproduce the above copyright
45 * notice, this list of conditions and the following disclaimer in the
46 * documentation and/or other materials provided with the distribution.
47 * 3. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 *
63 */
64
65 #ifndef _SYS_USERRET_H_
66 #define _SYS_USERRET_H_
67
68 #include <sys/lockdebug.h>
69 #include <sys/intr.h>
70
71 /*
72 * Define the MI code needed before returning to user mode, for
73 * trap and syscall.
74 */
75 static __inline void
mi_userret(struct lwp * l)76 mi_userret(struct lwp *l)
77 {
78 #ifndef __HAVE_PREEMPTION
79 struct cpu_info *ci;
80 #endif
81
82 KASSERT(l->l_blcnt == 0);
83 #ifndef __HAVE_PREEMPTION
84 KASSERT(curcpu()->ci_biglock_count == 0);
85 #endif
86
87 /*
88 * Handle "exceptional" events: pending signals, stop/exit actions,
89 * etc. Note that the event must be flagged BEFORE any AST is
90 * posted as we are reading unlocked.
91 */
92 #ifdef __HAVE_PREEMPTION
93 if (__predict_false(l->l_flag & LW_USERRET)) {
94 lwp_userret(l);
95 }
96 l->l_kpriority = false;
97 /*
98 * cpu_set_curpri(prio) is a MD optimized version of:
99 *
100 * kpreempt_disable();
101 * curcpu()->ci_schedstate.spc_curpriority = prio;
102 * kpreempt_enable();
103 */
104 cpu_set_curpri(l->l_priority); /* XXX this needs to die */
105 #else
106 ci = l->l_cpu;
107 if (((l->l_flag & LW_USERRET) | ci->ci_data.cpu_softints) != 0) {
108 lwp_userret(l);
109 ci = l->l_cpu;
110 }
111 l->l_kpriority = false;
112 ci->ci_schedstate.spc_curpriority = l->l_priority;
113 #endif
114
115 LOCKDEBUG_BARRIER(NULL, 0);
116 KASSERT(l->l_nopreempt == 0);
117 }
118
119 #endif /* !_SYS_USERRET_H_ */
120