sys/platform/pc64/include/lock.h

   1 /*
   2  * Copyright (c) 2003,2004 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $FreeBSD: src/sys/i386/include/lock.h,v 1.11.2.2 2000/09/30 02:49:34 ps Exp $
  35  * $DragonFly: src/sys/platform/pc32/include/lock.h,v 1.17 2008/06/19 21:32:55 aggelos Exp $
  36  */
  37
  38 #ifndef _MACHINE_LOCK_H_
  39 #define _MACHINE_LOCK_H_
  40
  41 #ifndef _CPU_PSL_H_
  42 #include <machine/psl.h>
  43 #endif
  44
  45 #ifdef LOCORE
  46
  47 /*
  48  * Spinlock assembly support.  Note: rax and rcx can be tromped.  No
  49  * other register will be.   Note that these routines are sometimes
  50  * called with (%edx) as the mem argument.
  51  *
  52  * Under UP the spinlock routines still serve to disable/restore
  53  * interrupts.
  54  */
  55
  56
  57 #ifdef SMP
  58
  59 #define SPIN_INIT(mem)                                          \
  60         movq    $0,mem ;                                        \
  61
  62 #define SPIN_INIT_NOREG(mem)                                    \
  63         SPIN_INIT(mem) ;                                        \
  64
  65 #define SPIN_LOCK(mem)                                          \
  66         pushfq ;                                                \
  67         popq    %rcx ;          /* flags */                     \
  68         cli ;                                                   \
  69         orq     $PSL_C,%rcx ;   /* make sure non-zero */        \
  70 7: ;                                                            \
  71         movq    $0,%rax ;       /* expected contents of lock */ \
  72         lock cmpxchgq %rcx,mem ; /* Z=1 (jz) on success */      \
  73         pause ;                                                 \
  74         jnz     7b ;                                            \
  75
  76 #define SPIN_LOCK_PUSH_REGS                                     \
  77         subq    $16,%rsp ;                                      \
  78         movq    %rcx,(%rsp) ;                                   \
  79         movq    %rax,8(%rsp) ;                                  \
  80
  81 #define SPIN_LOCK_POP_REGS                                      \
  82         movq    (%rsp),%rcx ;                                   \
  83         movq    8(%rsp),%rax ;                                  \
  84         addq    $16,%rsp ;                                      \
  85
  86 #define SPIN_LOCK_FRAME_SIZE    16
  87
  88 #define SPIN_LOCK_NOREG(mem)                                    \
  89         SPIN_LOCK_PUSH_REGS ;                                   \
  90         SPIN_LOCK(mem) ;                                        \
  91         SPIN_LOCK_POP_REGS ;                                    \
  92
  93 #define SPIN_UNLOCK(mem)                                        \
  94         pushq   mem ;                                           \
  95         movq    $0,mem ;                                        \
  96         popfq ;                                                 \
  97
  98 #define SPIN_UNLOCK_PUSH_REGS
  99 #define SPIN_UNLOCK_POP_REGS
 100 #define SPIN_UNLOCK_FRAME_SIZE  0
 101
 102 #define SPIN_UNLOCK_NOREG(mem)                                  \
 103         SPIN_UNLOCK(mem) ;                                      \
 104
 105 #else /* !SMP */
 106
 107 #define SPIN_LOCK(mem)                                          \
 108         pushfq ;                                                \
 109         cli ;                                                   \
 110         orq     $PSL_C,(%rsp) ;                                 \
 111         popq    mem ;                                           \
 112
 113 #define SPIN_LOCK_PUSH_RESG
 114 #define SPIN_LOCK_POP_REGS
 115 #define SPIN_LOCK_FRAME_SIZE    0
 116
 117 #define SPIN_UNLOCK(mem)                                        \
 118         pushq   mem ;                                           \
 119         movq    $0,mem ;                                        \
 120         popfq ;                                                 \
 121
 122 #define SPIN_UNLOCK_PUSH_REGS
 123 #define SPIN_UNLOCK_POP_REGS
 124 #define SPIN_UNLOCK_FRAME_SIZE  0
 125
 126 #endif  /* SMP */
 127
 128 #else   /* !LOCORE */
 129
 130 #ifdef _KERNEL
 131
 132 /*
 133  * Spinlock functions (UP and SMP).  Under UP a spinlock still serves
 134  * to disable/restore interrupts even if it doesn't spin.
 135  */
 136 struct spinlock_deprecated {
 137         volatile long   opaque;
 138 };
 139
 140 typedef struct spinlock_deprecated *spinlock_t;
 141
 142 void    mpintr_lock(void);      /* disables int / spinlock combo */
 143 void    mpintr_unlock(void);
 144 void    com_lock(void);         /* disables int / spinlock combo */
 145 void    com_unlock(void);
 146 void    imen_lock(void);        /* disables int / spinlock combo */
 147 void    imen_unlock(void);
 148 void    clock_lock(void);       /* disables int / spinlock combo */
 149 void    clock_unlock(void);
 150
 151 void    spin_lock_deprecated(spinlock_t lock);
 152 void    spin_unlock_deprecated(spinlock_t lock);
 153
 154 /*
 155  * Inline version of spinlock routines -- overrides assembly.  Only unlock
 156  * and init here please.
 157  */
 158 static __inline void
 159 spin_lock_init(spinlock_t lock)
 160 {
 161         lock->opaque = 0;
 162 }
 163
 164 #endif  /* _KERNEL */
 165
 166 #endif  /* LOCORE */
 167 #endif  /* !_MACHINE_LOCK_H_ */