| 1 | /* |
| 2 | * Copyright (c) 2003, Matthew Dillon, All rights reserved. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions |
| 6 | * are met: |
| 7 | * 1. Redistributions of source code must retain the above copyright |
| 8 | * notice, this list of conditions and the following disclaimer. |
| 9 | * 2. The name of the developer may NOT be used to endorse or promote products |
| 10 | * derived from this software without specific prior written permission. |
| 11 | * |
| 12 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| 13 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 14 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 15 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 16 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 17 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 18 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 19 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 20 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 21 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 22 | * SUCH DAMAGE. |
| 23 | * |
| 24 | * $FreeBSD: src/sys/i386/include/lock.h,v 1.11.2.2 2000/09/30 02:49:34 ps Exp $ |
| 25 | * $DragonFly: src/sys/i386/include/Attic/lock.h,v 1.4 2003/07/08 06:27:27 dillon Exp $ |
| 26 | */ |
| 27 | |
| 28 | #ifndef _MACHINE_LOCK_H_ |
| 29 | #define _MACHINE_LOCK_H_ |
| 30 | |
| 31 | #ifndef _MACHINE_PSL_H_ |
| 32 | #include <machine/psl.h> |
| 33 | #endif |
| 34 | |
| 35 | /* |
| 36 | * MP_FREE_LOCK is used by both assembly and C under SMP. |
| 37 | */ |
| 38 | #ifdef SMP |
| 39 | #define MP_FREE_LOCK 0xffffffff /* value of lock when free */ |
| 40 | #endif |
| 41 | |
| 42 | #ifdef LOCORE |
| 43 | |
| 44 | /* |
| 45 | * Spinlock assembly support. Note: eax and ecx can be tromped. No |
| 46 | * other register will be. Note that these routines are sometimes |
| 47 | * called with (%edx) as the mem argument. |
| 48 | * |
| 49 | * Under UP the spinlock routines still serve to disable/restore |
| 50 | * interrupts. |
| 51 | */ |
| 52 | |
| 53 | |
| 54 | #ifdef SMP |
| 55 | |
| 56 | #define SPIN_INIT(mem) \ |
| 57 | movl $0,mem ; \ |
| 58 | |
| 59 | #define SPIN_INIT_NOREG(mem) \ |
| 60 | SPIN_INIT(mem) ; \ |
| 61 | |
| 62 | #define SPIN_LOCK(mem) \ |
| 63 | pushfl ; \ |
| 64 | popl %ecx ; /* flags */ \ |
| 65 | cli ; \ |
| 66 | orl $PSL_C,%ecx ; /* make sure non-zero */ \ |
| 67 | 7: ; \ |
| 68 | movl $0,%eax ; /* expected contents of lock */ \ |
| 69 | lock cmpxchgl %ecx,mem ; /* Z=1 (jz) on success */ \ |
| 70 | jnz 7b ; \ |
| 71 | |
| 72 | #define SPIN_LOCK_PUSH_REGS \ |
| 73 | subl $8,%esp ; \ |
| 74 | movl %ecx,(%esp) ; \ |
| 75 | movl %eax,4(%esp) ; \ |
| 76 | |
| 77 | #define SPIN_LOCK_POP_REGS \ |
| 78 | movl (%esp),%ecx ; \ |
| 79 | movl 4(%esp),%eax ; \ |
| 80 | addl $8,%esp ; \ |
| 81 | |
| 82 | #define SPIN_LOCK_FRAME_SIZE 8 |
| 83 | |
| 84 | #define SPIN_LOCK_NOREG(mem) \ |
| 85 | SPIN_LOCK_PUSH_REGS ; \ |
| 86 | SPIN_LOCK(mem) ; \ |
| 87 | SPIN_LOCK_POP_REGS ; \ |
| 88 | |
| 89 | #define SPIN_UNLOCK(mem) \ |
| 90 | pushl mem ; \ |
| 91 | movl $0,mem ; \ |
| 92 | popfl ; \ |
| 93 | |
| 94 | #define SPIN_UNLOCK_PUSH_REGS |
| 95 | #define SPIN_UNLOCK_POP_REGS |
| 96 | #define SPIN_UNLOCK_FRAME_SIZE 0 |
| 97 | |
| 98 | #define SPIN_UNLOCK_NOREG(mem) \ |
| 99 | SPIN_UNLOCK(mem) ; \ |
| 100 | |
| 101 | #else |
| 102 | |
| 103 | #define SPIN_LOCK(mem) \ |
| 104 | pushfl ; \ |
| 105 | cli ; \ |
| 106 | orl $PSL_C,(%esp) ; \ |
| 107 | popl mem ; \ |
| 108 | |
| 109 | #define SPIN_LOCK_PUSH_RESG |
| 110 | #define SPIN_LOCK_POP_REGS |
| 111 | #define SPIN_LOCK_FRAME_SIZE 0 |
| 112 | |
| 113 | #define SPIN_UNLOCK(mem) \ |
| 114 | pushl mem ; \ |
| 115 | movl $0,mem ; \ |
| 116 | popfl ; \ |
| 117 | |
| 118 | #define SPIN_UNLOCK_PUSH_REGS |
| 119 | #define SPIN_UNLOCK_POP_REGS |
| 120 | #define SPIN_UNLOCK_FRAME_SIZE 0 |
| 121 | |
| 122 | #endif /* SMP */ |
| 123 | |
| 124 | #else /* LOCORE */ |
| 125 | |
| 126 | /* |
| 127 | * Spinlock functions (UP and SMP). Under UP a spinlock still serves |
| 128 | * to disable/restore interrupts even if it doesn't spin. |
| 129 | */ |
| 130 | struct spinlock { |
| 131 | volatile int opaque; |
| 132 | }; |
| 133 | |
| 134 | typedef struct spinlock *spinlock_t; |
| 135 | |
| 136 | void mpintr_lock(void); /* disables int / spinlock combo */ |
| 137 | void mpintr_unlock(void); |
| 138 | void com_lock(void); /* disables int / spinlock combo */ |
| 139 | void com_unlock(void); |
| 140 | void imen_lock(void); /* disables int / spinlock combo */ |
| 141 | void imen_unlock(void); |
| 142 | void clock_lock(void); /* disables int / spinlock combo */ |
| 143 | void clock_unlock(void); |
| 144 | void cons_lock(void); /* disables int / spinlock combo */ |
| 145 | void cons_unlock(void); |
| 146 | |
| 147 | extern struct spinlock smp_rv_spinlock; |
| 148 | |
| 149 | void spin_lock(spinlock_t lock); |
| 150 | void spin_lock_np(spinlock_t lock); |
| 151 | void spin_unlock(spinlock_t lock); |
| 152 | void spin_unlock_np(spinlock_t lock); |
| 153 | #if 0 |
| 154 | void spin_lock_init(spinlock_t lock); |
| 155 | #endif |
| 156 | |
| 157 | /* |
| 158 | * Inline version of spinlock routines -- overrides assembly. Only unlock |
| 159 | * and init here please. |
| 160 | */ |
| 161 | static __inline void |
| 162 | spin_lock_init(spinlock_t lock) |
| 163 | { |
| 164 | lock->opaque = 0; |
| 165 | } |
| 166 | |
| 167 | /* |
| 168 | * MP LOCK functions for SMP and UP. Under UP the MP lock does not exist |
| 169 | * but we leave a few functions intact as macros for convenience. |
| 170 | */ |
| 171 | #ifdef SMP |
| 172 | |
| 173 | void get_mplock(void); |
| 174 | int try_mplock(void); |
| 175 | void rel_mplock(void); |
| 176 | int cpu_try_mplock(void); |
| 177 | #if 0 |
| 178 | void cpu_rel_mplock(void); |
| 179 | #endif |
| 180 | void cpu_get_initial_mplock(void); |
| 181 | |
| 182 | extern u_int mp_lock; |
| 183 | |
| 184 | #define MP_LOCK_HELD() (mp_lock == mycpu->gd_cpuid) |
| 185 | #define ASSERT_MP_LOCK_HELD() KKASSERT(MP_LOCK_HELD()) |
| 186 | |
| 187 | static __inline void |
| 188 | cpu_rel_mplock(void) |
| 189 | { |
| 190 | mp_lock = MP_FREE_LOCK; |
| 191 | } |
| 192 | |
| 193 | #else |
| 194 | |
| 195 | #define get_mplock() |
| 196 | #define try_mplock() 1 |
| 197 | #define rel_mplock() |
| 198 | #define ASSERT_MP_LOCK_HELD() |
| 199 | |
| 200 | #endif /* SMP */ |
| 201 | #endif /* LOCORE */ |
| 202 | #endif /* !_MACHINE_LOCK_H_ */ |