freebsd-skq/sys/alpha/include/pcpu.h
jhb 8bfdafc934 Overhaul of the SMP code. Several portions of the SMP kernel support have
been made machine independent and various other adjustments have been made
to support Alpha SMP.

- It splits the per-process portions of hardclock() and statclock() off
  into hardclock_process() and statclock_process() respectively.  hardclock()
  and statclock() call the *_process() functions for the current process so
  that UP systems will run as before.  For SMP systems, it is simply necessary
  to ensure that all other processors execute the *_process() functions when the
  main clock functions are triggered on one CPU by an interrupt.  For the alpha
  4100, clock interrupts are delievered in a staggered broadcast fashion, so
  we simply call hardclock/statclock on the boot CPU and call the *_process()
  functions on the secondaries.  For x86, we call statclock and hardclock as
  usual and then call forward_hardclock/statclock in the MD code to send an IPI
  to cause the AP's to execute forwared_hardclock/statclock which then call the
  *_process() functions.
- forward_signal() and forward_roundrobin() have been reworked to be MI and to
  involve less hackery.  Now the cpu doing the forward sets any flags, etc. and
  sends a very simple IPI_AST to the other cpu(s).  AST IPIs now just basically
  return so that they can execute ast() and don't bother with setting the
  astpending or needresched flags themselves.  This also removes the loop in
  forward_signal() as sched_lock closes the race condition that the loop worked
  around.
- need_resched(), resched_wanted() and clear_resched() have been changed to take
  a process to act on rather than assuming curproc so that they can be used to
  implement forward_roundrobin() as described above.
- Various other SMP variables have been moved to a MI subr_smp.c and a new
  header sys/smp.h declares MI SMP variables and API's.   The IPI API's from
  machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h.
- The globaldata_register() and globaldata_find() functions as well as the
  SLIST of globaldata structures has become MI and moved into subr_smp.c.
  Also, the globaldata list is only available if SMP support is compiled in.

Reviewed by:	jake, peter
Looked over by:	eivind
2001-04-27 19:28:25 +00:00

74 lines
2.8 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_GLOBALDATA_H_
#define _MACHINE_GLOBALDATA_H_
#ifdef _KERNEL
#include <sys/queue.h>
/*
* This structure maps out the global data that needs to be kept on a
* per-cpu basis. genassym uses this to generate offsets for the assembler
* code, which also provides external symbols so that C can get at them as
* though they were really globals. This structure is pointed to by
* the per-cpu system value (see alpha_pal_rdval() and alpha_pal_wrval()).
* Inside the kernel, the globally reserved register t7 is used to
* point at the globaldata structure.
*/
struct globaldata {
struct alpha_pcb gd_idlepcb; /* pcb for idling */
struct proc *gd_curproc; /* current process */
struct proc *gd_idleproc; /* idle process */
struct proc *gd_fpcurproc; /* fp state owner */
struct pcb *gd_curpcb; /* current pcb */
struct timeval gd_switchtime;
int gd_switchticks;
u_int gd_cpuid; /* this cpu number */
u_int gd_other_cpus; /* all other cpus */
u_int64_t gd_idlepcbphys; /* pa of gd_idlepcb */
u_int64_t gd_pending_ipis; /* pending IPI events */
u_int32_t gd_next_asn; /* next ASN to allocate */
u_int32_t gd_current_asngen; /* ASN rollover check */
SLIST_ENTRY(globaldata) gd_allcpu;
struct lock_list_entry *gd_spinlocks;
#ifdef KTR_PERCPU
volatile int gd_ktr_idx; /* Index into trace table */
char *gd_ktr_buf;
char gd_ktr_buf_data[0];
#endif
};
void globaldata_init(struct globaldata *pcpu, int cpuid, size_t sz);
#endif /* _KERNEL */
#endif /* !_MACHINE_GLOBALDATA_H_ */