2 * Copyright (c) 2010 Juniper Networks, Inc.
3 * Copyright (c) 2009 Robert N. M. Watson
4 * Copyright (c) 2009 Bjoern A. Zeeb <bz@FreeBSD.org>
5 * Copyright (c) 2008 Yahoo!, Inc.
8 * Written by: John Baldwin <jhb@FreeBSD.org>
10 * This software was developed by Robert N. M. Watson under contract
11 * to Juniper Networks, Inc.
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the author nor the names of any co-contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/param.h>
43 #include <sys/sysctl.h>
48 #include "kvm_private.h"
50 static struct nlist kvm_pcpu_nl[] = {
51 { .n_name = "_cpuid_to_pcpu" },
52 { .n_name = "_mp_maxcpus" },
57 * Kernel per-CPU data state. We cache this stuff on the first
60 * XXXRW: Possibly, this (and kvmpcpu_nl) should be per-kvm_t, in case the
61 * consumer has multiple handles in flight to differently configured
64 static void **pcpu_data;
67 #define NL_CPUID_TO_PCPU 0
68 #define NL_MP_MAXCPUS 1
71 _kvm_pcpu_init(kvm_t *kd)
77 if (kvm_nlist(kd, kvm_pcpu_nl) < 0)
79 if (kvm_pcpu_nl[NL_CPUID_TO_PCPU].n_value == 0) {
80 _kvm_err(kd, kd->program, "unable to find cpuid_to_pcpu");
83 if (kvm_pcpu_nl[NL_MP_MAXCPUS].n_value == 0) {
84 _kvm_err(kd, kd->program, "unable to find mp_maxcpus");
87 if (kvm_read(kd, kvm_pcpu_nl[NL_MP_MAXCPUS].n_value, &max,
88 sizeof(max)) != sizeof(max)) {
89 _kvm_err(kd, kd->program, "cannot read mp_maxcpus");
92 len = max * sizeof(void *);
95 _kvm_err(kd, kd->program, "out of memory");
98 if (kvm_read(kd, kvm_pcpu_nl[NL_CPUID_TO_PCPU].n_value, data, len) !=
100 _kvm_err(kd, kd->program, "cannot read cpuid_to_pcpu array");
110 _kvm_pcpu_clear(void)
119 kvm_getpcpu(kvm_t *kd, int cpu)
129 if (_kvm_pcpu_init(kd) < 0)
132 if (cpu >= maxcpu || pcpu_data[cpu] == NULL)
135 buf = malloc(sizeof(struct pcpu));
137 _kvm_err(kd, kd->program, "out of memory");
140 if (kvm_read(kd, (uintptr_t)pcpu_data[cpu], buf,
141 sizeof(struct pcpu)) != sizeof(struct pcpu)) {
142 _kvm_err(kd, kd->program, "unable to read per-CPU data");
150 kvm_getmaxcpu(kvm_t *kd)
159 if (_kvm_pcpu_init(kd) < 0)
165 _kvm_dpcpu_setcpu(kvm_t *kd, u_int cpu, int report_error)
168 if (!kd->dpcpu_initialized) {
170 _kvm_err(kd, kd->program, "%s: not initialized",
174 if (cpu >= kd->dpcpu_maxcpus) {
176 _kvm_err(kd, kd->program, "%s: CPU %u too big",
180 if (kd->dpcpu_off[cpu] == 0) {
182 _kvm_err(kd, kd->program, "%s: CPU %u not found",
186 kd->dpcpu_curcpu = cpu;
187 kd->dpcpu_curoff = kd->dpcpu_off[cpu];
192 * Set up libkvm to handle dynamic per-CPU memory.
195 _kvm_dpcpu_init(kvm_t *kd)
197 struct nlist nl[] = {
198 #define NLIST_START_SET_PCPU 0
199 { .n_name = "___start_" DPCPU_SETNAME },
200 #define NLIST_STOP_SET_PCPU 1
201 { .n_name = "___stop_" DPCPU_SETNAME },
202 #define NLIST_DPCPU_OFF 2
203 { .n_name = "_dpcpu_off" },
204 #define NLIST_MP_MAXCPUS 3
205 { .n_name = "_mp_maxcpus" },
208 uintptr_t *dpcpu_off_buf;
213 * Locate and cache locations of important symbols using the internal
214 * version of _kvm_nlist, turning off initialization to avoid
215 * recursion in case of unresolveable symbols.
217 if (_kvm_nlist(kd, nl, 0) != 0)
219 if (kvm_read(kd, nl[NLIST_MP_MAXCPUS].n_value, &dpcpu_maxcpus,
220 sizeof(dpcpu_maxcpus)) != sizeof(dpcpu_maxcpus))
222 len = dpcpu_maxcpus * sizeof(*dpcpu_off_buf);
223 dpcpu_off_buf = malloc(len);
224 if (dpcpu_off_buf == NULL)
226 if (kvm_read(kd, nl[NLIST_DPCPU_OFF].n_value, dpcpu_off_buf, len) !=
231 kd->dpcpu_start = nl[NLIST_START_SET_PCPU].n_value;
232 kd->dpcpu_stop = nl[NLIST_STOP_SET_PCPU].n_value;
233 kd->dpcpu_maxcpus = dpcpu_maxcpus;
234 kd->dpcpu_off = dpcpu_off_buf;
235 kd->dpcpu_initialized = 1;
236 (void)_kvm_dpcpu_setcpu(kd, 0, 0);
241 * Check whether the dpcpu module has been initialized sucessfully or not,
242 * initialize it if permitted.
245 _kvm_dpcpu_initialized(kvm_t *kd, int intialize)
248 if (kd->dpcpu_initialized || !intialize)
249 return (kd->dpcpu_initialized);
251 (void)_kvm_dpcpu_init(kd);
253 return (kd->dpcpu_initialized);
257 * Check whether the value is within the dpcpu symbol range and only if so
258 * adjust the offset relative to the current offset.
261 _kvm_dpcpu_validaddr(kvm_t *kd, uintptr_t value)
267 if (!kd->dpcpu_initialized)
270 if (value < kd->dpcpu_start || value >= kd->dpcpu_stop)
273 return (kd->dpcpu_curoff + value);
277 kvm_dpcpu_setcpu(kvm_t *kd, u_int cpu)
281 if (!kd->dpcpu_initialized) {
282 ret = _kvm_dpcpu_init(kd);
284 _kvm_err(kd, kd->program, "%s: init failed",
290 return (_kvm_dpcpu_setcpu(kd, cpu, 1));