4572ff9c78
and change the u_int mtx_saveintr member of struct mtx to a critical_t mtx_savecrit. - On the alpha we no longer need a custom _get_spin_lock() macro to avoid an extra PAL call, so remove it. - Partially fix using mutexes with WITNESS in modules. Change all the _mtx_{un,}lock_{spin,}_flags() macros to accept explicit file and line parameters and rename them to use a prefix of two underscores. Inside of kern_mutex.c, generate wrapper functions for _mtx_{un,}lock_{spin,}_flags() (only using a prefix of one underscore) that are called from modules. The macros mtx_{un,}lock_{spin,}_flags() are mapped to the __mtx_* macros inside of the kernel to inline the usual case of mutex operations and map to the internal _mtx_* functions in the module case so that modules will use WITNESS and KTR logging if the kernel is compiled with support for it.
318 lines
9.3 KiB
C
318 lines
9.3 KiB
C
/*-
|
|
* Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Berkeley Software Design Inc's name may not be used to endorse or
|
|
* promote products derived from this software without specific prior
|
|
* written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _MACHINE_MUTEX_H_
|
|
#define _MACHINE_MUTEX_H_
|
|
|
|
#ifndef LOCORE
|
|
|
|
#ifdef _KERNEL
|
|
#include <machine/psl.h>
|
|
|
|
/* Global locks */
|
|
extern struct mtx clock_lock;
|
|
|
|
#define mtx_intr_enable(mutex) (mutex)->mtx_savecrit |= PSL_I
|
|
|
|
/*
|
|
* Assembly macros (for internal use only)
|
|
*------------------------------------------------------------------------------
|
|
*/
|
|
#define _V(x) __STRING(x)
|
|
|
|
#if 0
|
|
/* #ifndef I386_CPU */
|
|
|
|
/*
|
|
* For 486 and newer processors.
|
|
*/
|
|
|
|
/* Get a sleep lock, deal with recursion inline. */
|
|
#define _getlock_sleep(mtxp, tid, type) ({ \
|
|
int _res = MTX_UNOWNED; \
|
|
\
|
|
__asm __volatile ( \
|
|
" " MPLOCKED "" \
|
|
" cmpxchgl %3,%1;" /* Try */ \
|
|
" jz 1f;" /* Got it */ \
|
|
" andl $" _V(MTX_FLAGMASK) ",%0;" /* turn off spec bits */ \
|
|
" cmpl %0,%3;" /* already have it? */ \
|
|
" je 2f;" /* yes, recurse */ \
|
|
" pushl %4;" \
|
|
" pushl %5;" \
|
|
" call mtx_enter_hard;" \
|
|
" addl $8,%%esp;" \
|
|
" jmp 1f;" \
|
|
"2:" \
|
|
" " MPLOCKED "" \
|
|
" orl $" _V(MTX_RECURSE) ",%1;" \
|
|
" incl %2;" \
|
|
"1:" \
|
|
"# getlock_sleep" \
|
|
: "+a" (_res), /* 0 */ \
|
|
"+m" (mtxp->mtx_lock), /* 1 */ \
|
|
"+m" (mtxp->mtx_recurse) /* 2 */ \
|
|
: "r" (tid), /* 3 (input) */ \
|
|
"gi" (type), /* 4 */ \
|
|
"g" (mtxp) /* 5 */ \
|
|
: "cc", "memory", "ecx", "edx" /* used */ ); \
|
|
})
|
|
|
|
/* Get a spin lock, handle recursion inline (as the less common case) */
|
|
#define _getlock_spin_block(mtxp, tid, type) ({ \
|
|
int _res = MTX_UNOWNED; \
|
|
\
|
|
__asm __volatile ( \
|
|
" pushfl;" \
|
|
" cli;" \
|
|
" " MPLOCKED "" \
|
|
" cmpxchgl %3,%1;" /* Try */ \
|
|
" jz 2f;" /* got it */ \
|
|
" pushl %4;" \
|
|
" pushl %5;" \
|
|
" call mtx_enter_hard;" /* mtx_enter_hard(mtxp, type, oflags) */ \
|
|
" addl $12,%%esp;" \
|
|
" jmp 1f;" \
|
|
"2: popl %2;" /* save flags */ \
|
|
"1:" \
|
|
"# getlock_spin_block" \
|
|
: "+a" (_res), /* 0 */ \
|
|
"+m" (mtxp->mtx_lock), /* 1 */ \
|
|
"=m" (mtxp->mtx_savecrit) /* 2 */ \
|
|
: "r" (tid), /* 3 (input) */ \
|
|
"gi" (type), /* 4 */ \
|
|
"g" (mtxp) /* 5 */ \
|
|
: "cc", "memory", "ecx", "edx" /* used */ ); \
|
|
})
|
|
|
|
/*
|
|
* Get a lock without any recursion handling. Calls the hard enter function if
|
|
* we can't get it inline.
|
|
*/
|
|
#define _getlock_norecurse(mtxp, tid, type) ({ \
|
|
int _res = MTX_UNOWNED; \
|
|
\
|
|
__asm __volatile ( \
|
|
" " MPLOCKED "" \
|
|
" cmpxchgl %2,%1;" /* Try */ \
|
|
" jz 1f;" /* got it */ \
|
|
" pushl %3;" \
|
|
" pushl %4;" \
|
|
" call mtx_enter_hard;" /* mtx_enter_hard(mtxp, type) */ \
|
|
" addl $8,%%esp;" \
|
|
"1:" \
|
|
"# getlock_norecurse" \
|
|
: "+a" (_res), /* 0 */ \
|
|
"+m" (mtxp->mtx_lock) /* 1 */ \
|
|
: "r" (tid), /* 2 (input) */ \
|
|
"gi" (type), /* 3 */ \
|
|
"g" (mtxp) /* 4 */ \
|
|
: "cc", "memory", "ecx", "edx" /* used */ ); \
|
|
})
|
|
|
|
/*
|
|
* Release a sleep lock assuming we haven't recursed on it, recursion is handled
|
|
* in the hard function.
|
|
*/
|
|
#define _exitlock_norecurse(mtxp, tid, type) ({ \
|
|
int _tid = (int)(tid); \
|
|
\
|
|
__asm __volatile ( \
|
|
" " MPLOCKED "" \
|
|
" cmpxchgl %4,%0;" /* try easy rel */ \
|
|
" jz 1f;" /* released! */ \
|
|
" pushl %2;" \
|
|
" pushl %3;" \
|
|
" call mtx_exit_hard;" \
|
|
" addl $8,%%esp;" \
|
|
"1:" \
|
|
"# exitlock_norecurse" \
|
|
: "+m" (mtxp->mtx_lock), /* 0 */ \
|
|
"+a" (_tid) /* 1 */ \
|
|
: "gi" (type), /* 2 (input) */ \
|
|
"g" (mtxp), /* 3 */ \
|
|
"r" (MTX_UNOWNED) /* 4 */ \
|
|
: "cc", "memory", "ecx", "edx" /* used */ ); \
|
|
})
|
|
|
|
/*
|
|
* Release a sleep lock when its likely we recursed (the code to
|
|
* deal with simple recursion is inline).
|
|
*/
|
|
#define _exitlock(mtxp, tid, type) ({ \
|
|
int _tid = (int)(tid); \
|
|
\
|
|
__asm __volatile ( \
|
|
" " MPLOCKED "" \
|
|
" cmpxchgl %5,%0;" /* try easy rel */ \
|
|
" jz 1f;" /* released! */ \
|
|
" testl $" _V(MTX_RECURSE) ",%%eax;" /* recursed? */ \
|
|
" jnz 3f;" /* handle recursion */ \
|
|
/* Lock not recursed and contested: do the hard way */ \
|
|
" pushl %3;" \
|
|
" pushl %4;" \
|
|
" call mtx_exit_hard;" /* mtx_exit_hard(mtxp,type) */ \
|
|
" addl $8,%%esp;" \
|
|
" jmp 1f;" \
|
|
/* lock recursed, lower recursion level */ \
|
|
"3: decl %1;" /* one less level */ \
|
|
" jnz 1f;" /* still recursed, done */ \
|
|
" lock; andl $~" _V(MTX_RECURSE) ",%0;" /* turn off recurse flag */ \
|
|
"1:" \
|
|
"# exitlock" \
|
|
: "+m" (mtxp->mtx_lock), /* 0 */ \
|
|
"+m" (mtxp->mtx_recurse), /* 1 */ \
|
|
"+a" (_tid) /* 2 */ \
|
|
: "gi" (type), /* 3 (input) */ \
|
|
"g" (mtxp), /* 4 */ \
|
|
"r" (MTX_UNOWNED) /* 5 */ \
|
|
: "cc", "memory", "ecx", "edx" /* used */ ); \
|
|
})
|
|
|
|
/*
|
|
* Release a spin lock (with possible recursion).
|
|
*
|
|
* We use xchgl to clear lock (instead of simple store) to flush posting
|
|
* buffers and make the change visible to other CPU's.
|
|
*/
|
|
#define _exitlock_spin(mtxp) ({ \
|
|
int _res; \
|
|
\
|
|
__asm __volatile ( \
|
|
" movl %1,%2;" \
|
|
" decl %2;" \
|
|
" js 1f;" \
|
|
" movl %2,%1;" \
|
|
" jmp 2f;" \
|
|
"1: movl $ " _V(MTX_UNOWNED) ",%2;" \
|
|
" pushl %3;" \
|
|
" xchgl %2,%0;" \
|
|
" popfl;" \
|
|
"2:" \
|
|
"# exitlock_spin" \
|
|
: "+m" (mtxp->mtx_lock), /* 0 */ \
|
|
"+m" (mtxp->mtx_recurse), /* 1 */ \
|
|
"=r" (_res) /* 2 */ \
|
|
: "g" (mtxp->mtx_savecrit) /* 3 */ \
|
|
: "cc", "memory", "ecx" /* used */ ); \
|
|
})
|
|
|
|
#endif /* I386_CPU */
|
|
|
|
#undef _V
|
|
|
|
#endif /* _KERNEL */
|
|
|
|
#else /* !LOCORE */
|
|
|
|
/*
|
|
* Simple assembly macros to get and release mutexes.
|
|
*
|
|
* Note: All of these macros accept a "flags" argument and are analoguous
|
|
* to the mtx_lock_flags and mtx_unlock_flags general macros. If one
|
|
* desires to not pass a flag, the value 0 may be passed as second
|
|
* argument.
|
|
*
|
|
* XXX: We only have MTX_LOCK_SPIN and MTX_UNLOCK_SPIN for now, since that's
|
|
* all we use right now. We should add MTX_LOCK and MTX_UNLOCK (for sleep
|
|
* locks) in the near future, however.
|
|
*/
|
|
#define MTX_LOCK_SPIN(lck, flags) \
|
|
pushl %eax ; \
|
|
pushl %ecx ; \
|
|
pushl %ebx ; \
|
|
movl $(MTX_UNOWNED) , %eax ; \
|
|
movl PCPU(CURPROC), %ebx ; \
|
|
pushfl ; \
|
|
popl %ecx ; \
|
|
cli ; \
|
|
MPLOCKED cmpxchgl %ebx, lck+MTX_LOCK ; \
|
|
jz 2f ; \
|
|
cmpl lck+MTX_LOCK, %ebx ; \
|
|
je 3f ; \
|
|
pushl $0 ; \
|
|
pushl $0 ; \
|
|
pushl %ecx ; \
|
|
pushl $flags ; \
|
|
pushl $lck ; \
|
|
call _mtx_lock_spin ; \
|
|
addl $0x14, %esp ; \
|
|
jmp 1f ; \
|
|
3: movl lck+MTX_RECURSECNT, %ebx ; \
|
|
incl %ebx ; \
|
|
movl %ebx, lck+MTX_RECURSECNT ; \
|
|
jmp 1f ; \
|
|
2: movl %ecx, lck+MTX_SAVECRIT ; \
|
|
1: popl %ebx ; \
|
|
popl %ecx ; \
|
|
popl %eax
|
|
|
|
#define MTX_UNLOCK_SPIN(lck) \
|
|
pushl %edx ; \
|
|
pushl %eax ; \
|
|
movl lck+MTX_SAVECRIT, %edx ; \
|
|
movl lck+MTX_RECURSECNT, %eax ; \
|
|
testl %eax, %eax ; \
|
|
jne 2f ; \
|
|
movl $(MTX_UNOWNED), %eax ; \
|
|
xchgl %eax, lck+MTX_LOCK ; \
|
|
pushl %edx ; \
|
|
popfl ; \
|
|
jmp 1f ; \
|
|
2: decl %eax ; \
|
|
movl %eax, lck+MTX_RECURSECNT ; \
|
|
1: popl %eax ; \
|
|
popl %edx
|
|
|
|
/*
|
|
* XXX: These two are broken right now and need to be made to work for
|
|
* XXX: sleep locks, as the above two work for spin locks. We're not in
|
|
* XXX: too much of a rush to do these as we do not use them right now.
|
|
*/
|
|
#define MTX_ENTER(lck, type) \
|
|
pushl $0 ; /* dummy __LINE__ */ \
|
|
pushl $0 ; /* dummy __FILE__ */ \
|
|
pushl $type ; \
|
|
pushl $lck ; \
|
|
call _mtx_lock_XXX ; \
|
|
addl $16,%esp
|
|
|
|
#define MTX_EXIT(lck, type) \
|
|
pushl $0 ; /* dummy __LINE__ */ \
|
|
pushl $0 ; /* dummy __FILE__ */ \
|
|
pushl $type ; \
|
|
pushl $lck ; \
|
|
call _mtx_unlock_XXX ; \
|
|
addl $16,%esp
|
|
|
|
#endif /* !LOCORE */
|
|
#endif /* __MACHINE_MUTEX_H */
|