1 /* 2 * Copyright (c) 2001 Wind River Systems, Inc. 3 * All rights reserved. 4 * Written by: John Baldwin <jhb@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 4. Neither the name of the author nor the names of any co-contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * $FreeBSD$ 31 */ 32 33 /* 34 * This module provides MI support for per-cpu data. 35 * 36 * Each architecture determines the mapping of logical CPU IDs to physical 37 * CPUs. The requirements of this mapping are as follows: 38 * - Logical CPU IDs must reside in the range 0 ... MAXCPU - 1. 39 * - The mapping is not required to be dense. That is, there may be 40 * gaps in the mappings. 41 * - The platform sets the value of MAXCPU in <machine/param.h>. 42 * - It is suggested, but not required, that in the non-SMP case, the 43 * platform define MAXCPU to be 1 and define the logical ID of the 44 * sole CPU as 0. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/pcpu.h> 50 51 static struct globaldata *cpuid_to_globaldata[MAXCPU]; 52 struct cpuhead cpuhead = SLIST_HEAD_INITIALIZER(cpuhead); 53 54 /* 55 * Register a struct globaldata. 56 */ 57 void 58 globaldata_register(struct globaldata *globaldata) 59 { 60 61 KASSERT(globaldata->gd_cpuid >= 0 && globaldata->gd_cpuid < MAXCPU, 62 ("globaldata_register: invalid cpuid")); 63 cpuid_to_globaldata[globaldata->gd_cpuid] = globaldata; 64 SLIST_INSERT_HEAD(&cpuhead, globaldata, gd_allcpu); 65 } 66 67 /* 68 * Locate a struct globaldata by cpu id. 69 */ 70 struct globaldata * 71 globaldata_find(u_int cpuid) 72 { 73 74 return (cpuid_to_globaldata[cpuid]); 75 } 76