1/* $NetBSD: userret.h,v 1.28 2019/05/17 03:34:27 ozaki-r 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#include <sys/psref.h>
71
72/*
73 * Define the MI code needed before returning to user mode, for
74 * trap and syscall.
75 */
76static __inline void
77mi_userret(struct lwp *l)
78{
79#ifndef __HAVE_PREEMPTION
80 struct cpu_info *ci;
81#endif
82
83 KASSERT(l->l_blcnt == 0);
84#ifndef __HAVE_PREEMPTION
85 KASSERT(curcpu()->ci_biglock_count == 0);
86#endif
87
88 /*
89 * Handle "exceptional" events: pending signals, stop/exit actions,
90 * etc. Note that the event must be flagged BEFORE any AST is
91 * posted as we are reading unlocked.
92 */
93#ifdef __HAVE_PREEMPTION
94 if (__predict_false(l->l_flag & LW_USERRET)) {
95 lwp_userret(l);
96 }
97 l->l_kpriority = false;
98 /*
99 * cpu_set_curpri(prio) is a MD optimized version of:
100 *
101 * kpreempt_disable();
102 * curcpu()->ci_schedstate.spc_curpriority = prio;
103 * kpreempt_enable();
104 */
105 cpu_set_curpri(l->l_priority); /* XXX this needs to die */
106#else
107 ci = l->l_cpu;
108 if (((l->l_flag & LW_USERRET) | ci->ci_data.cpu_softints) != 0) {
109 lwp_userret(l);
110 ci = l->l_cpu;
111 }
112 l->l_kpriority = false;
113 ci->ci_schedstate.spc_curpriority = l->l_priority;
114#endif
115
116 LOCKDEBUG_BARRIER(NULL, 0);
117 KASSERT(l->l_nopreempt == 0);
118 PSREF_DEBUG_BARRIER();
119 KASSERT(l->l_psrefs == 0);
120}
121
122#endif /* !_SYS_USERRET_H_ */
123