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author | Thomas Bushnell <thomas@gnu.org> | 1999-04-26 05:58:44 +0000 |
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committer | Thomas Bushnell <thomas@gnu.org> | 1999-04-26 05:58:44 +0000 |
commit | 86297c41a26f18d924e64fc93321c59cbc4c48dd (patch) | |
tree | 376954c6b95b735d361875319a1a2a9db6a27527 /linux/src/include/asm-i386/semaphore.h | |
parent | 851137902d3e7ad87af177487df3eea53e940a1c (diff) | |
download | gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.tar.gz gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.tar.bz2 gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.zip |
1998-11-30 OKUJI Yoshinori <okuji@kuicr.kyoto-u.ac.jp>
Clean up linux emulation code to make it architecture-independent
as much as possible.
* linux: Renamed from linuxdev.
* Makefile.in (objfiles): Add linux.o instead of linuxdev.o.
(MAKE): New variable. Used for the linux.o target.
* configure.in: Add AC_CHECK_TOOL(MAKE, make).
* i386/i386/spl.h: Include <i386/ipl.h>, for compatibility with
OSF Mach 3.0. Suggested by Elgin Lee <ehl@funghi.com>.
* linux/src: Renamed from linux/linux.
* linux/dev: Renamed from linux/mach.
* linux/Drivers.in (AC_INIT): Use dev/include/linux/autoconf.h,
instead of mach/include/linux/autoconf.h.
* Makefile.in (all): Target ../linux.o instead of ../linuxdev.o.
* linux/dev/drivers/block/genhd.c: Include <machine/spl.h> instead
of <i386/ipl.h>.
* linux/dev/drivers/net/auto_irq.c: Remove unneeded header files,
<i386/ipl.h> and <i386/pic.h>.
* linux/dev/init/main.c: Many i386-dependent codes moved to ...
* linux/dev/arch/i386/irq.c: ... here.
* linux/dev/arch/i386/setup.c: New file.
* linux/dev/arch/i386/linux_emul.h: Likewise.
* linux/dev/arch/i386/glue/timer.c: Merged into sched.c.
* linux/dev/arch/i386/glue/sched.c: Include <machine/spl.h> instead
of <i386/ipl.h>, and moved to ...
* linux/dev/kernel/sched.c: ... here.
* linux/dev/arch/i386/glue/block.c: Include <machine/spl.h> and
<linux_emul.h>, instead of i386-dependent header files, and
moved to ...
* linux/dev/glue/blocl.c: ... here.
* linux/dev/arch/i386/glue/net.c: Include <machine/spl.h> and
<linux_emul.h>, instead of i386-dependent header files, and
moved to ...
* linux/dev/glue/net.c: ... here.
* linux/dev/arch/i386/glue/misc.c: Remove `x86' and moved to ...
* linux/dev/glue/misc.c: ... here.
* linux/dev/arch/i386/glue/kmem.c: Moved to ...
* linux/dev/glue/kmem.c: ... here.
Diffstat (limited to 'linux/src/include/asm-i386/semaphore.h')
-rw-r--r-- | linux/src/include/asm-i386/semaphore.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/linux/src/include/asm-i386/semaphore.h b/linux/src/include/asm-i386/semaphore.h new file mode 100644 index 00000000..1486d1c1 --- /dev/null +++ b/linux/src/include/asm-i386/semaphore.h @@ -0,0 +1,127 @@ +#ifndef _I386_SEMAPHORE_H +#define _I386_SEMAPHORE_H + +#include <linux/linkage.h> +#include <asm/system.h> + +/* + * SMP- and interrupt-safe semaphores.. + * + * (C) Copyright 1996 Linus Torvalds + * + * Modified 1996-12-23 by Dave Grothe <dave@gcom.com> to fix bugs in + * the original code and to make semaphore waits + * interruptible so that processes waiting on + * semaphores can be killed. + * + * If you would like to see an analysis of this implementation, please + * ftp to gcom.com and download the file + * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. + * + */ + +struct semaphore { + int count; + int waking; + int lock ; /* to make waking testing atomic */ + struct wait_queue * wait; +}; + +#define MUTEX ((struct semaphore) { 1, 0, 0, NULL }) +#define MUTEX_LOCKED ((struct semaphore) { 0, 0, 0, NULL }) + +asmlinkage void down_failed(void /* special register calling convention */); +asmlinkage void up_wakeup(void /* special register calling convention */); + +extern void __down(struct semaphore * sem); +extern void __up(struct semaphore * sem); + +/* + * This is ugly, but we want the default case to fall through. + * "down_failed" is a special asm handler that calls the C + * routine that actually waits. See arch/i386/lib/semaphore.S + */ +extern inline void down(struct semaphore * sem) +{ + __asm__ __volatile__( + "# atomic down operation\n\t" + "movl $1f,%%eax\n\t" +#ifdef __SMP__ + "lock ; " +#endif + "decl 0(%0)\n\t" + "js " SYMBOL_NAME_STR(down_failed) "\n" + "1:\n" + :/* no outputs */ + :"c" (sem) + :"ax","dx","memory"); +} + +/* + * Primitives to spin on a lock. Needed only for SMP version. + */ +extern inline void get_buzz_lock(int *lock_ptr) +{ +#ifdef __SMP__ + while (xchg(lock_ptr,1) != 0) ; +#endif +} /* get_buzz_lock */ + +extern inline void give_buzz_lock(int *lock_ptr) +{ +#ifdef __SMP__ + *lock_ptr = 0 ; +#endif +} /* give_buzz_lock */ + +asmlinkage int down_failed_interruptible(void); /* params in registers */ + +/* + * This version waits in interruptible state so that the waiting + * process can be killed. The down_failed_interruptible routine + * returns negative for signalled and zero for semaphore acquired. + */ +extern inline int down_interruptible(struct semaphore * sem) +{ + int ret ; + + __asm__ __volatile__( + "# atomic interruptible down operation\n\t" + "movl $2f,%%eax\n\t" +#ifdef __SMP__ + "lock ; " +#endif + "decl 0(%1)\n\t" + "js " SYMBOL_NAME_STR(down_failed_interruptible) "\n\t" + "xorl %%eax,%%eax\n" + "2:\n" + :"=a" (ret) + :"c" (sem) + :"ax","dx","memory"); + + return(ret) ; +} + +/* + * Note! This is subtle. We jump to wake people up only if + * the semaphore was negative (== somebody was waiting on it). + * The default case (no contention) will result in NO + * jumps for both down() and up(). + */ +extern inline void up(struct semaphore * sem) +{ + __asm__ __volatile__( + "# atomic up operation\n\t" + "movl $1f,%%eax\n\t" +#ifdef __SMP__ + "lock ; " +#endif + "incl 0(%0)\n\t" + "jle " SYMBOL_NAME_STR(up_wakeup) + "\n1:" + :/* no outputs */ + :"c" (sem) + :"ax", "dx", "memory"); +} + +#endif |