xref: /freebsd/sys/kern/subr_pcpu.c (revision 0bbc882680ceece07eb134ddeb7fceffb59ea018)
1ba228f6dSJohn Baldwin /*
2ba228f6dSJohn Baldwin  * Copyright (c) 2001 Wind River Systems, Inc.
3ba228f6dSJohn Baldwin  * All rights reserved.
4ba228f6dSJohn Baldwin  * Written by: John Baldwin <jhb@FreeBSD.org>
5ba228f6dSJohn Baldwin  *
6ba228f6dSJohn Baldwin  * Redistribution and use in source and binary forms, with or without
7ba228f6dSJohn Baldwin  * modification, are permitted provided that the following conditions
8ba228f6dSJohn Baldwin  * are met:
9ba228f6dSJohn Baldwin  * 1. Redistributions of source code must retain the above copyright
10ba228f6dSJohn Baldwin  *    notice, this list of conditions and the following disclaimer.
11ba228f6dSJohn Baldwin  * 2. Redistributions in binary form must reproduce the above copyright
12ba228f6dSJohn Baldwin  *    notice, this list of conditions and the following disclaimer in the
13ba228f6dSJohn Baldwin  *    documentation and/or other materials provided with the distribution.
14ba228f6dSJohn Baldwin  * 4. Neither the name of the author nor the names of any co-contributors
15ba228f6dSJohn Baldwin  *    may be used to endorse or promote products derived from this software
16ba228f6dSJohn Baldwin  *    without specific prior written permission.
17ba228f6dSJohn Baldwin  *
18ba228f6dSJohn Baldwin  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19ba228f6dSJohn Baldwin  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20ba228f6dSJohn Baldwin  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21ba228f6dSJohn Baldwin  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22ba228f6dSJohn Baldwin  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23ba228f6dSJohn Baldwin  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24ba228f6dSJohn Baldwin  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25ba228f6dSJohn Baldwin  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26ba228f6dSJohn Baldwin  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27ba228f6dSJohn Baldwin  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28ba228f6dSJohn Baldwin  * SUCH DAMAGE.
29ba228f6dSJohn Baldwin  *
30ba228f6dSJohn Baldwin  * $FreeBSD$
31ba228f6dSJohn Baldwin  */
32ba228f6dSJohn Baldwin 
33ba228f6dSJohn Baldwin /*
34ba228f6dSJohn Baldwin  * This module provides MI support for per-cpu data.
35882bcf58SJohn Baldwin  *
36882bcf58SJohn Baldwin  * Each architecture determines the mapping of logical CPU IDs to physical
37882bcf58SJohn Baldwin  * CPUs.  The requirements of this mapping are as follows:
38882bcf58SJohn Baldwin  *  - Logical CPU IDs must reside in the range 0 ... MAXCPU - 1.
39882bcf58SJohn Baldwin  *  - The mapping is not required to be dense.  That is, there may be
40882bcf58SJohn Baldwin  *    gaps in the mappings.
41882bcf58SJohn Baldwin  *  - The platform sets the value of MAXCPU in <machine/param.h>.
42882bcf58SJohn Baldwin  *  - It is suggested, but not required, that in the non-SMP case, the
43882bcf58SJohn Baldwin  *    platform define MAXCPU to be 1 and define the logical ID of the
44882bcf58SJohn Baldwin  *    sole CPU as 0.
45ba228f6dSJohn Baldwin  */
46ba228f6dSJohn Baldwin 
470bbc8826SJohn Baldwin #include "opt_ddb.h"
480bbc8826SJohn Baldwin 
49ba228f6dSJohn Baldwin #include <sys/param.h>
50ba228f6dSJohn Baldwin #include <sys/systm.h>
510bbc8826SJohn Baldwin #include <sys/linker_set.h>
520bbc8826SJohn Baldwin #include <sys/lock.h>
53ba228f6dSJohn Baldwin #include <sys/pcpu.h>
540bbc8826SJohn Baldwin #include <sys/proc.h>
550bbc8826SJohn Baldwin #include <ddb/ddb.h>
56ba228f6dSJohn Baldwin 
570bbc8826SJohn Baldwin static struct pcpu *cpuid_to_pcpu[MAXCPU];
58ba228f6dSJohn Baldwin struct cpuhead cpuhead = SLIST_HEAD_INITIALIZER(cpuhead);
59ba228f6dSJohn Baldwin 
60ba228f6dSJohn Baldwin /*
610bbc8826SJohn Baldwin  * Initialize the MI portions of a struct pcpu.
62ba228f6dSJohn Baldwin  */
63ba228f6dSJohn Baldwin void
640bbc8826SJohn Baldwin pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
65ba228f6dSJohn Baldwin {
66ba228f6dSJohn Baldwin 
670bbc8826SJohn Baldwin 	bzero(pcpu, size);
680bbc8826SJohn Baldwin 	KASSERT(cpuid >= 0 && cpuid < MAXCPU,
690bbc8826SJohn Baldwin 	    ("pcpu_init: invalid cpuid %d", cpuid));
700bbc8826SJohn Baldwin 	pcpu->pc_cpuid = cpuid;
710bbc8826SJohn Baldwin 	cpuid_to_pcpu[cpuid] = pcpu;
720bbc8826SJohn Baldwin 	SLIST_INSERT_HEAD(&cpuhead, pcpu, pc_allcpu);
730bbc8826SJohn Baldwin 	cpu_pcpu_init(pcpu, cpuid, size);
74ba228f6dSJohn Baldwin }
75ba228f6dSJohn Baldwin 
76ba228f6dSJohn Baldwin /*
770bbc8826SJohn Baldwin  * Destroy a struct pcpu.
78ba228f6dSJohn Baldwin  */
790bbc8826SJohn Baldwin void
800bbc8826SJohn Baldwin pcpu_destroy(struct pcpu *pcpu)
81ba228f6dSJohn Baldwin {
82ba228f6dSJohn Baldwin 
830bbc8826SJohn Baldwin 	SLIST_REMOVE(&cpuhead, pcpu, pcpu, pc_allcpu);
840bbc8826SJohn Baldwin 	cpuid_to_pcpu[pcpu->pc_cpuid] = NULL;
85ba228f6dSJohn Baldwin }
860bbc8826SJohn Baldwin 
870bbc8826SJohn Baldwin /*
880bbc8826SJohn Baldwin  * Locate a struct pcpu by cpu id.
890bbc8826SJohn Baldwin  */
900bbc8826SJohn Baldwin struct pcpu *
910bbc8826SJohn Baldwin pcpu_find(u_int cpuid)
920bbc8826SJohn Baldwin {
930bbc8826SJohn Baldwin 
940bbc8826SJohn Baldwin 	return (cpuid_to_pcpu[cpuid]);
950bbc8826SJohn Baldwin }
960bbc8826SJohn Baldwin 
970bbc8826SJohn Baldwin #ifdef DDB
980bbc8826SJohn Baldwin DB_SHOW_COMMAND(pcpu, db_show_pcpu)
990bbc8826SJohn Baldwin {
1000bbc8826SJohn Baldwin 	struct pcpu *pc;
1010bbc8826SJohn Baldwin 	struct thread *td;
1020bbc8826SJohn Baldwin 	int id;
1030bbc8826SJohn Baldwin 
1040bbc8826SJohn Baldwin 	if (have_addr)
1050bbc8826SJohn Baldwin 		id = ((addr >> 4) % 16) * 10 + (addr % 16);
1060bbc8826SJohn Baldwin 	else
1070bbc8826SJohn Baldwin 		id = PCPU_GET(cpuid);
1080bbc8826SJohn Baldwin 	pc = pcpu_find(id);
1090bbc8826SJohn Baldwin 	if (pc == NULL) {
1100bbc8826SJohn Baldwin 		db_printf("CPU %d not found\n", id);
1110bbc8826SJohn Baldwin 		return;
1120bbc8826SJohn Baldwin 	}
1130bbc8826SJohn Baldwin 	db_printf("cpuid        = %d\n", pc->pc_cpuid);
1140bbc8826SJohn Baldwin 	db_printf("curthread    = ");
1150bbc8826SJohn Baldwin 	td = pc->pc_curthread;
1160bbc8826SJohn Baldwin 	if (td != NULL)
1170bbc8826SJohn Baldwin 		db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
1180bbc8826SJohn Baldwin 		    td->td_proc->p_comm);
1190bbc8826SJohn Baldwin 	else
1200bbc8826SJohn Baldwin 		db_printf("none\n");
1210bbc8826SJohn Baldwin 	db_printf("curpcb       = %p\n", pc->pc_curpcb);
1220bbc8826SJohn Baldwin 	db_printf("fpcurthread  = ");
1230bbc8826SJohn Baldwin 	td = pc->pc_fpcurthread;
1240bbc8826SJohn Baldwin 	if (td != NULL)
1250bbc8826SJohn Baldwin 		db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
1260bbc8826SJohn Baldwin 		    td->td_proc->p_comm);
1270bbc8826SJohn Baldwin 	else
1280bbc8826SJohn Baldwin 		db_printf("none\n");
1290bbc8826SJohn Baldwin 	db_printf("idlethread   = ");
1300bbc8826SJohn Baldwin 	td = pc->pc_idlethread;
1310bbc8826SJohn Baldwin 	if (td != NULL)
1320bbc8826SJohn Baldwin 		db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
1330bbc8826SJohn Baldwin 		    td->td_proc->p_comm);
1340bbc8826SJohn Baldwin 	else
1350bbc8826SJohn Baldwin 		db_printf("none\n");
1360bbc8826SJohn Baldwin 	db_show_mdpcpu(pc);
1370bbc8826SJohn Baldwin 
1380bbc8826SJohn Baldwin #ifdef WITNESS
1390bbc8826SJohn Baldwin 	db_printf("spin locks held:\n");
1400bbc8826SJohn Baldwin 	witness_list_locks(&pc->pc_spinlocks);
1410bbc8826SJohn Baldwin #endif
1420bbc8826SJohn Baldwin }
1430bbc8826SJohn Baldwin #endif
144