freebsd-dev/sys/i386/include/globals.h
Matthew Dillon 36e9f877df Commit major SMP cleanups and move the BGL (big giant lock) in the
syscall path inward.  A system call may select whether it needs the MP
    lock or not (the default being that it does need it).

    A great deal of conditional SMP code for various deadended experiments
    has been removed.  'cil' and 'cml' have been removed entirely, and the
    locking around the cpl has been removed.  The conditional
    separately-locked fast-interrupt code has been removed, meaning that
    interrupts must hold the CPL now (but they pretty much had to anyway).
    Another reason for doing this is that the original separate-lock for
    interrupts just doesn't apply to the interrupt thread mechanism being
    contemplated.

    Modifications to the cpl may now ONLY occur while holding the MP
    lock.  For example, if an otherwise MP safe syscall needs to mess with
    the cpl, it must hold the MP lock for the duration and must (as usual)
    save/restore the cpl in a nested fashion.

    This is precursor work for the real meat coming later: avoiding having
    to hold the MP lock for common syscalls and I/O's and interrupt threads.
    It is expected that the spl mechanisms and new interrupt threading
    mechanisms will be able to run in tandem, allowing a slow piecemeal
    transition to occur.

    This patch should result in a moderate performance improvement due to
    the considerable amount of code that has been removed from the critical
    path, especially the simplification of the spl*() calls.  The real
    performance gains will come later.

Approved by: jkh
Reviewed by: current, bde (exception.s)
Some work taken from: luoqi's patch
2000-03-28 07:16:37 +00:00

148 lines
4.8 KiB
C

/*-
* Copyright (c) 1999 Luoqi Chen <luoqi@freebsd.org>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_GLOBALS_H_
#define _MACHINE_GLOBALS_H_
#ifdef _KERNEL
#define GLOBAL_LVALUE(name, type) \
(*(type *)_global_ptr_##name())
#define GLOBAL_RVALUE(name, type) \
((type)_global_##name())
/* non-volatile version */
#define GLOBAL_LVALUE_NV(name, type) \
(*(type *)_global_ptr_##name##_nv())
#define GLOBAL_RVALUE_NV(name, type) \
((type)_global_##name##_nv())
#define GLOBAL_FUNC(name) \
static __inline void *_global_ptr_##name(void) { \
void *val; \
__asm __volatile("movl $gd_" #name ",%0;" \
"addl %%fs:globaldata,%0" : "=r" (val)); \
return (val); \
} \
static __inline void *_global_ptr_##name##_nv(void) { \
void *val; \
__asm("movl $gd_" #name ",%0;" \
"addl %%fs:globaldata,%0" : "=r" (val)); \
return (val); \
} \
static __inline int _global_##name(void) { \
int val; \
__asm __volatile("movl %%fs:gd_" #name ",%0" : "=r" (val)); \
return (val); \
} \
static __inline int _global_##name##_nv(void) { \
int val; \
__asm("movl %%fs:gd_" #name ",%0" : "=r" (val)); \
return (val); \
} \
static __inline void _global_##name##_set(int val) { \
__asm __volatile("movl %0,%%fs:gd_" #name : : "r" (val)); \
} \
static __inline void _global_##name##_set_nv(int val) { \
__asm("movl %0,%%fs:gd_" #name : : "r" (val)); \
}
#if defined(SMP) || defined(KLD_MODULE) || defined(ACTUALLY_LKM_NOT_KERNEL)
/*
* The following set of macros works for UP kernel as well, but for maximum
* performance we allow the global variables to be accessed directly. On the
* other hand, kernel modules should always use these macros to maintain
* portability between UP and SMP kernels.
*/
#define curproc GLOBAL_RVALUE_NV(curproc, struct proc *)
#define curpcb GLOBAL_RVALUE_NV(curpcb, struct pcb *)
#define npxproc GLOBAL_LVALUE(npxproc, struct proc *)
#define common_tss GLOBAL_LVALUE(common_tss, struct i386tss)
#define switchtime GLOBAL_LVALUE(switchtime, struct timeval)
#define switchticks GLOBAL_LVALUE(switchticks, int)
#define common_tssd GLOBAL_LVALUE(common_tssd, struct segment_descriptor)
#define tss_gdt GLOBAL_LVALUE(tss_gdt, struct segment_descriptor *)
#define astpending GLOBAL_LVALUE(astpending, u_int)
#ifdef USER_LDT
#define currentldt GLOBAL_LVALUE(currentldt, int)
#endif
#ifdef SMP
#define cpuid GLOBAL_RVALUE(cpuid, u_int)
#define other_cpus GLOBAL_LVALUE(other_cpus, u_int)
#define inside_intr GLOBAL_LVALUE(inside_intr, int)
#define prv_CMAP1 GLOBAL_LVALUE(prv_CMAP1, pt_entry_t *)
#define prv_CMAP2 GLOBAL_LVALUE(prv_CMAP2, pt_entry_t *)
#define prv_CMAP3 GLOBAL_LVALUE(prv_CMAP3, pt_entry_t *)
#define prv_PMAP1 GLOBAL_LVALUE(prv_PMAP1, pt_entry_t *)
#define prv_CADDR1 GLOBAL_RVALUE(prv_CADDR1, caddr_t)
#define prv_CADDR2 GLOBAL_RVALUE(prv_CADDR2, caddr_t)
#define prv_CADDR3 GLOBAL_RVALUE(prv_CADDR3, caddr_t)
#define prv_PADDR1 GLOBAL_RVALUE(prv_PADDR1, unsigned *)
#endif
#endif /*UP kernel*/
GLOBAL_FUNC(curproc)
GLOBAL_FUNC(astpending)
GLOBAL_FUNC(curpcb)
GLOBAL_FUNC(npxproc)
GLOBAL_FUNC(common_tss)
GLOBAL_FUNC(switchtime)
GLOBAL_FUNC(switchticks)
GLOBAL_FUNC(common_tssd)
GLOBAL_FUNC(tss_gdt)
#ifdef USER_LDT
GLOBAL_FUNC(currentldt)
#endif
#ifdef SMP
GLOBAL_FUNC(cpuid)
GLOBAL_FUNC(other_cpus)
GLOBAL_FUNC(inside_intr)
GLOBAL_FUNC(prv_CMAP1)
GLOBAL_FUNC(prv_CMAP2)
GLOBAL_FUNC(prv_CMAP3)
GLOBAL_FUNC(prv_PMAP1)
GLOBAL_FUNC(prv_CADDR1)
GLOBAL_FUNC(prv_CADDR2)
GLOBAL_FUNC(prv_CADDR3)
GLOBAL_FUNC(prv_PADDR1)
#endif
#define SET_CURPROC(x) (_global_curproc_set_nv((int)x))
#endif /* _KERNEL */
#endif /* !_MACHINE_GLOBALS_H_ */