sys/platform/pc64/include/lock.h

   1 /*
   2  * Copyright (c) 2003,2008 The DragonFly Project.
   3  * Copyright (c) 2003 Matthew Dillon.
   4  * All rights reserved.
   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. The name of the developer may NOT be used to endorse or promote products
  12  *    derived from this software without specific prior written permission.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/sys/i386/include/lock.h,v 1.11.2.2 2000/09/30 02:49:34 ps Exp $
  27  * $DragonFly: src/sys/platform/pc64/include/lock.h,v 1.4 2008/08/29 17:07:17 dillon Exp $
  28  */
  29
  30 #ifndef _MACHINE_LOCK_H_
  31 #define _MACHINE_LOCK_H_
  32
  33 #ifndef _CPU_PSL_H_
  34 #include <machine/psl.h>
  35 #endif
  36
  37 /*
  38  * MP_FREE_LOCK is used by both assembly and C under SMP.
  39  */
  40 #ifdef SMP
  41 #define MP_FREE_LOCK            0xffffffff      /* value of lock when free */
  42 #endif
  43
  44 #ifdef LOCORE
  45
  46 /*
  47  * Spinlock assembly support.  Note: rax and rcx can be tromped.  No
  48  * other register will be.   Note that these routines are sometimes
  49  * called with (%edx) as the mem argument.
  50  *
  51  * Under UP the spinlock routines still serve to disable/restore
  52  * interrupts.
  53  */
  54
  55
  56 #ifdef SMP
  57
  58 #define SPIN_INIT(mem)                                          \
  59         movq    $0,mem ;                                        \
  60
  61 #define SPIN_INIT_NOREG(mem)                                    \
  62         SPIN_INIT(mem) ;                                        \
  63
  64 #define SPIN_LOCK(mem)                                          \
  65         pushfq ;                                                \
  66         popq    %rcx ;          /* flags */                     \
  67         cli ;                                                   \
  68         orl     $PSL_C,%rcx ;   /* make sure non-zero */        \
  69 7: ;                                                            \
  70         movq    $0,%rax ;       /* expected contents of lock */ \
  71         lock cmpxchgq %rcx,mem ; /* Z=1 (jz) on success */      \
  72         jnz     7b ;                                            \
  73
  74 #define SPIN_LOCK_PUSH_REGS                                     \
  75         subq    $2*8,%rsp ;                                     \
  76         movq    %rcx,(%rsp) ;                                   \
  77         movq    %rax,8(%rsp) ;                                  \
  78
  79 #define SPIN_LOCK_POP_REGS                                      \
  80         movq    (%rsp),%rcx ;                                   \
  81         movq    8(%rsp),%rax ;                                  \
  82         addq    $2*8,%rsp ;                                     \
  83
  84 #define SPIN_LOCK_FRAME_SIZE    8
  85
  86 #define SPIN_LOCK_NOREG(mem)                                    \
  87         SPIN_LOCK_PUSH_REGS ;                                   \
  88         SPIN_LOCK(mem) ;                                        \
  89         SPIN_LOCK_POP_REGS ;                                    \
  90
  91 #define SPIN_UNLOCK(mem)                                        \
  92         pushq   mem ;                                           \
  93         movq    $0,mem ;                                        \
  94         popfq ;                                                 \
  95
  96 #define SPIN_UNLOCK_PUSH_REGS
  97 #define SPIN_UNLOCK_POP_REGS
  98 #define SPIN_UNLOCK_FRAME_SIZE  0
  99
 100 #define SPIN_UNLOCK_NOREG(mem)                                  \
 101         SPIN_UNLOCK(mem) ;                                      \
 102
 103 #else /* !SMP */
 104
 105 #define SPIN_LOCK(mem)                                          \
 106         pushfq ;                                                \
 107         cli ;                                                   \
 108         orq     $PSL_C,(%rsp) ;                                 \
 109         popq    mem ;                                           \
 110
 111 #define SPIN_LOCK_PUSH_RESG
 112 #define SPIN_LOCK_POP_REGS
 113 #define SPIN_LOCK_FRAME_SIZE    0
 114
 115 #define SPIN_UNLOCK(mem)                                        \
 116         pushq   mem ;                                           \
 117         movq    $0,mem ;                                        \
 118         popfq ;                                                 \
 119
 120 #define SPIN_UNLOCK_PUSH_REGS
 121 #define SPIN_UNLOCK_POP_REGS
 122 #define SPIN_UNLOCK_FRAME_SIZE  0
 123
 124 #endif  /* SMP */
 125
 126 #else   /* !LOCORE */
 127
 128 #ifdef _KERNEL
 129
 130 /*
 131  * Spinlock functions (UP and SMP).  Under UP a spinlock still serves
 132  * to disable/restore interrupts even if it doesn't spin.
 133  */
 134 struct spinlock_deprecated {
 135         volatile long   opaque;
 136 };
 137
 138 typedef struct spinlock_deprecated *spinlock_t;
 139
 140 void    mpintr_lock(void);      /* disables int / spinlock combo */
 141 void    mpintr_unlock(void);
 142 void    com_lock(void);         /* disables int / spinlock combo */
 143 void    com_unlock(void);
 144 void    imen_lock(void);        /* disables int / spinlock combo */
 145 void    imen_unlock(void);
 146 void    clock_lock(void);       /* disables int / spinlock combo */
 147 void    clock_unlock(void);
 148
 149 extern struct spinlock_deprecated smp_rv_spinlock;
 150
 151 void    spin_lock_deprecated(spinlock_t);
 152 void    spin_unlock_deprecated(spinlock_t);
 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 #if defined(_KERNEL) || defined(_UTHREAD)
 167
 168 /*
 169  * MP LOCK functions for SMP and UP.  Under UP the MP lock does not exist
 170  * but we leave a few functions intact as macros for convenience.
 171  */
 172 #ifdef SMP
 173
 174 void    get_mplock(void);
 175 int     try_mplock(void);
 176 void    rel_mplock(void);
 177 int     cpu_try_mplock(void);
 178 void    cpu_get_initial_mplock(void);
 179
 180 extern u_int    mp_lock;
 181
 182 #define MP_LOCK_HELD()   (mp_lock == mycpu->gd_cpuid)
 183 #define ASSERT_MP_LOCK_HELD(td)   KASSERT(MP_LOCK_HELD(), ("MP_LOCK_HELD(): not held thread %p", td))
 184
 185 static __inline void
 186 cpu_rel_mplock(void)
 187 {
 188         mp_lock = MP_FREE_LOCK;
 189 }
 190
 191 #else
 192
 193 #define get_mplock()
 194 #define try_mplock()    1
 195 #define rel_mplock()
 196 #define MP_LOCK_HELD()  (!0)
 197 #define ASSERT_MP_LOCK_HELD(td)
 198
 199 #endif  /* SMP */
 200 #endif  /* _KERNEL || _UTHREAD */
 201 #endif  /* LOCORE */
 202 #endif  /* !_MACHINE_LOCK_H_ */