freebsd-dev/sys/amd64/include/critical.h
Peter Wemm afa8862328 Commit MD parts of a loosely functional AMD64 port. This is based on
a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from.  There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code.  pmap uses
  a variation of the PAE code in order to avoid having to worry about 4
  levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
  i386 loader.  This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
  not been translated yet, and some that I cheated and wrote dumb C
  versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
  passing, as is native on the amd64 ABI), and the 'syscall' instruction
  for syscalls.  int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
  of places (eg: to find which register they use to replace the trashed
  %rcx register in the syscall instruction).  As a result, there is not a
  lot of similarity.  I did look at NetBSD a few times while debugging to
  get some ideas about what I might have done wrong in my first attempt.
2003-05-01 01:05:25 +00:00

73 lines
1.4 KiB
C

/*-
* Copyright (c) 2002 Matthew Dillon. This code is distributed under
* the BSD copyright, /usr/src/COPYRIGHT.
*
* This file contains prototypes and high-level inlines related to
* machine-level critical function support:
*
* cpu_critical_enter() - inlined
* cpu_critical_exit() - inlined
* cpu_critical_fork_exit() - prototyped
* cpu_thread_link() - prototyped
* related support functions residing
* in <arch>/<arch>/critical.c - prototyped
*
* $FreeBSD$
*/
#ifndef _MACHINE_CRITICAL_H_
#define _MACHINE_CRITICAL_H_
__BEGIN_DECLS
/*
* Prototypes - see <arch>/<arch>/critical.c
*/
void cpu_critical_fork_exit(void);
void cpu_thread_link(struct thread *td);
#ifdef __GNUC__
/*
* cpu_critical_enter:
*
* This routine is called from critical_enter() on the 0->1 transition
* of td_critnest, prior to it being incremented to 1.
*/
static __inline void
cpu_critical_enter(void)
{
struct thread *td;
td = curthread;
td->td_md.md_savecrit = intr_disable();
}
/*
* cpu_critical_exit:
*
* This routine is called from critical_exit() on a 1->0 transition
* of td_critnest, after it has been decremented to 0. We are
* exiting the last critical section.
*/
static __inline void
cpu_critical_exit(void)
{
struct thread *td;
td = curthread;
intr_restore(td->td_md.md_savecrit);
}
#else /* !__GNUC__ */
void cpu_critical_enter(void)
void cpu_critical_exit(void)
#endif /* __GNUC__ */
__END_DECLS
#endif /* !_MACHINE_CRITICAL_H_ */