1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1999 Eivind Eklund <eivind@FreeBSD.org> 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 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #ifndef _SYS_KASSERT_H_ 32 #define _SYS_KASSERT_H_ 33 34 #include <sys/cdefs.h> 35 36 #ifdef _KERNEL 37 extern const char *panicstr; /* panic message */ 38 extern bool panicked; 39 #define KERNEL_PANICKED() __predict_false(panicked) 40 41 #ifdef INVARIANTS /* The option is always available */ 42 #define VNASSERT(exp, vp, msg) do { \ 43 if (__predict_false(!(exp))) { \ 44 vn_printf(vp, "VNASSERT failed: %s not true at %s:%d (%s)\n",\ 45 #exp, __FILE__, __LINE__, __func__); \ 46 kassert_panic msg; \ 47 } \ 48 } while (0) 49 #define MPASSERT(exp, mp, msg) do { \ 50 if (__predict_false(!(exp))) { \ 51 printf("MPASSERT mp %p failed: %s not true at %s:%d (%s)\n",\ 52 (mp), #exp, __FILE__, __LINE__, __func__); \ 53 kassert_panic msg; \ 54 } \ 55 } while (0) 56 #define VNPASS(exp, vp) do { \ 57 const char *_exp = #exp; \ 58 VNASSERT(exp, vp, ("condition %s not met at %s:%d (%s)", \ 59 _exp, __FILE__, __LINE__, __func__)); \ 60 } while (0) 61 #define MPPASS(exp, mp) do { \ 62 const char *_exp = #exp; \ 63 MPASSERT(exp, mp, ("condition %s not met at %s:%d (%s)", \ 64 _exp, __FILE__, __LINE__, __func__)); \ 65 } while (0) 66 #define __assert_unreachable() \ 67 panic("executing segment marked as unreachable at %s:%d (%s)\n", \ 68 __FILE__, __LINE__, __func__) 69 #else /* INVARIANTS */ 70 #define VNASSERT(exp, vp, msg) do { \ 71 } while (0) 72 #define MPASSERT(exp, mp, msg) do { \ 73 } while (0) 74 #define VNPASS(exp, vp) do { \ 75 } while (0) 76 #define MPPASS(exp, mp) do { \ 77 } while (0) 78 #define __assert_unreachable() __unreachable() 79 #endif /* INVARIANTS */ 80 81 #ifndef CTASSERT /* Allow lint to override */ 82 #define CTASSERT(x) _Static_assert(x, "compile-time assertion failed") 83 #endif 84 85 /* 86 * These functions need to be declared before the KASSERT macro is invoked in 87 * !KASSERT_PANIC_OPTIONAL builds, so their declarations are sort of out of 88 * place compared to other function definitions in this header. On the other 89 * hand, this header is a bit disorganized anyway. 90 */ 91 void panic(const char *, ...) __dead2 __printflike(1, 2); 92 void vpanic(const char *, __va_list) __dead2 __printflike(1, 0); 93 #endif /* _KERNEL */ 94 95 #if defined(_STANDALONE) 96 /* 97 * Until we have more experience with KASSERTS that are called 98 * from the boot loader, they are off. The bootloader does this 99 * a little differently than the kernel (we just call printf atm). 100 * we avoid most of the common functions in the boot loader, so 101 * declare printf() here too. 102 */ 103 int printf(const char *, ...) __printflike(1, 2); 104 # define kassert_panic printf 105 #else /* !_STANDALONE */ 106 # if defined(WITNESS) || defined(INVARIANT_SUPPORT) 107 # ifdef KASSERT_PANIC_OPTIONAL 108 void kassert_panic(const char *fmt, ...) __printflike(1, 2); 109 # else 110 # define kassert_panic panic 111 # endif /* KASSERT_PANIC_OPTIONAL */ 112 # endif /* defined(WITNESS) || defined(INVARIANT_SUPPORT) */ 113 #endif /* _STANDALONE */ 114 115 #if (defined(_KERNEL) && defined(INVARIANTS)) || defined(_STANDALONE) 116 #define KASSERT(exp,msg) do { \ 117 if (__predict_false(!(exp))) \ 118 kassert_panic msg; \ 119 } while (0) 120 #else /* !(KERNEL && INVARIANTS) && !_STANDALONE */ 121 #define KASSERT(exp,msg) do { \ 122 } while (0) 123 #endif /* (_KERNEL && INVARIANTS) || _STANDALONE */ 124 125 #ifdef _KERNEL 126 /* 127 * Helpful macros for quickly coming up with assertions with informative 128 * panic messages. 129 */ 130 #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) 131 #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) 132 #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) 133 #define MPASS4(ex, what, file, line) \ 134 KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) 135 136 /* 137 * Assert that a pointer can be loaded from memory atomically. 138 * 139 * This assertion enforces stronger alignment than necessary. For example, 140 * on some architectures, atomicity for unaligned loads will depend on 141 * whether or not the load spans multiple cache lines. 142 */ 143 #define ASSERT_ATOMIC_LOAD_PTR(var, msg) \ 144 KASSERT(sizeof(var) == sizeof(void *) && \ 145 ((uintptr_t)&(var) & (sizeof(void *) - 1)) == 0, msg) 146 /* 147 * Assert that a thread is in critical(9) section. 148 */ 149 #define CRITICAL_ASSERT(td) \ 150 KASSERT((td)->td_critnest >= 1, ("Not in critical section")) 151 152 /* 153 * If we have already panic'd and this is the thread that called 154 * panic(), then don't block on any mutexes but silently succeed. 155 * Otherwise, the kernel will deadlock since the scheduler isn't 156 * going to run the thread that holds any lock we need. 157 */ 158 #define SCHEDULER_STOPPED_TD(td) ({ \ 159 MPASS((td) == curthread); \ 160 __predict_false((td)->td_stopsched); \ 161 }) 162 #define SCHEDULER_STOPPED() SCHEDULER_STOPPED_TD(curthread) 163 #endif /* _KERNEL */ 164 165 #endif /* _SYS_KASSERT_H_ */ 166