freebsd-skq/sys/kern/subr_pcpu.c
jhb 21b6b26912 Overhaul the per-CPU support a bit:
- The MI portions of struct globaldata have been consolidated into a MI
  struct pcpu.  The MD per-CPU data are specified via a macro defined in
  machine/pcpu.h.  A macro was chosen over a struct mdpcpu so that the
  interface would be cleaner (PCPU_GET(my_md_field) vs.
  PCPU_GET(md.md_my_md_field)).
- All references to globaldata are changed to pcpu instead.  In a UP kernel,
  this data was stored as global variables which is where the original name
  came from.  In an SMP world this data is per-CPU and ideally private to each
  CPU outside of the context of debuggers.  This also included combining
  machine/globaldata.h and machine/globals.h into machine/pcpu.h.
- The pointer to the thread using the FPU on i386 was renamed from
  npxthread to fpcurthread to be identical with other architectures.
- Make the show pcpu ddb command MI with a MD callout to display MD
  fields.
- The globaldata_register() function was renamed to pcpu_init() and now
  init's MI fields of a struct pcpu in addition to registering it with
  the internal array and list.
- A pcpu_destroy() function was added to remove a struct pcpu from the
  internal array and list.

Tested on:	alpha, i386
Reviewed by:	peter, jake
2001-12-11 23:33:44 +00:00

144 lines
4.1 KiB
C

/*
* Copyright (c) 2001 Wind River Systems, Inc.
* All rights reserved.
* Written by: John Baldwin <jhb@FreeBSD.org>
*
* 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.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
* $FreeBSD$
*/
/*
* This module provides MI support for per-cpu data.
*
* Each architecture determines the mapping of logical CPU IDs to physical
* CPUs. The requirements of this mapping are as follows:
* - Logical CPU IDs must reside in the range 0 ... MAXCPU - 1.
* - The mapping is not required to be dense. That is, there may be
* gaps in the mappings.
* - The platform sets the value of MAXCPU in <machine/param.h>.
* - It is suggested, but not required, that in the non-SMP case, the
* platform define MAXCPU to be 1 and define the logical ID of the
* sole CPU as 0.
*/
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/linker_set.h>
#include <sys/lock.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <ddb/ddb.h>
static struct pcpu *cpuid_to_pcpu[MAXCPU];
struct cpuhead cpuhead = SLIST_HEAD_INITIALIZER(cpuhead);
/*
* Initialize the MI portions of a struct pcpu.
*/
void
pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
{
bzero(pcpu, size);
KASSERT(cpuid >= 0 && cpuid < MAXCPU,
("pcpu_init: invalid cpuid %d", cpuid));
pcpu->pc_cpuid = cpuid;
cpuid_to_pcpu[cpuid] = pcpu;
SLIST_INSERT_HEAD(&cpuhead, pcpu, pc_allcpu);
cpu_pcpu_init(pcpu, cpuid, size);
}
/*
* Destroy a struct pcpu.
*/
void
pcpu_destroy(struct pcpu *pcpu)
{
SLIST_REMOVE(&cpuhead, pcpu, pcpu, pc_allcpu);
cpuid_to_pcpu[pcpu->pc_cpuid] = NULL;
}
/*
* Locate a struct pcpu by cpu id.
*/
struct pcpu *
pcpu_find(u_int cpuid)
{
return (cpuid_to_pcpu[cpuid]);
}
#ifdef DDB
DB_SHOW_COMMAND(pcpu, db_show_pcpu)
{
struct pcpu *pc;
struct thread *td;
int id;
if (have_addr)
id = ((addr >> 4) % 16) * 10 + (addr % 16);
else
id = PCPU_GET(cpuid);
pc = pcpu_find(id);
if (pc == NULL) {
db_printf("CPU %d not found\n", id);
return;
}
db_printf("cpuid = %d\n", pc->pc_cpuid);
db_printf("curthread = ");
td = pc->pc_curthread;
if (td != NULL)
db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
td->td_proc->p_comm);
else
db_printf("none\n");
db_printf("curpcb = %p\n", pc->pc_curpcb);
db_printf("fpcurthread = ");
td = pc->pc_fpcurthread;
if (td != NULL)
db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
td->td_proc->p_comm);
else
db_printf("none\n");
db_printf("idlethread = ");
td = pc->pc_idlethread;
if (td != NULL)
db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
td->td_proc->p_comm);
else
db_printf("none\n");
db_show_mdpcpu(pc);
#ifdef WITNESS
db_printf("spin locks held:\n");
witness_list_locks(&pc->pc_spinlocks);
#endif
}
#endif