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>
42 #include <sys/cpuset.h>
44 #include <sys/sysctl.h>
50 #include "kvm_private.h"
52 static struct nlist kvm_pcpu_nl[] = {
53 { .n_name = "_cpuid_to_pcpu" },
54 { .n_name = "_mp_maxcpus" },
59 * Kernel per-CPU data state. We cache this stuff on the first
62 * XXXRW: Possibly, this (and kvmpcpu_nl) should be per-kvm_t, in case the
63 * consumer has multiple handles in flight to differently configured
66 static void **pcpu_data;
69 #define NL_CPUID_TO_PCPU 0
70 #define NL_MP_MAXCPUS 1
73 _kvm_pcpu_init(kvm_t *kd)
79 if (kvm_nlist(kd, kvm_pcpu_nl) < 0)
81 if (kvm_pcpu_nl[NL_CPUID_TO_PCPU].n_value == 0) {
82 _kvm_err(kd, kd->program, "unable to find cpuid_to_pcpu");
85 if (kvm_pcpu_nl[NL_MP_MAXCPUS].n_value == 0) {
86 _kvm_err(kd, kd->program, "unable to find mp_maxcpus");
89 if (kvm_read(kd, kvm_pcpu_nl[NL_MP_MAXCPUS].n_value, &max,
90 sizeof(max)) != sizeof(max)) {
91 _kvm_err(kd, kd->program, "cannot read mp_maxcpus");
94 len = max * sizeof(void *);
97 _kvm_err(kd, kd->program, "out of memory");
100 if (kvm_read(kd, kvm_pcpu_nl[NL_CPUID_TO_PCPU].n_value, data, len) !=
102 _kvm_err(kd, kd->program, "cannot read cpuid_to_pcpu array");
112 _kvm_pcpu_clear(void)
121 kvm_getpcpu(kvm_t *kd, int cpu)
133 kcpusetsize = sysconf(_SC_CPUSET_SIZE);
134 if (kcpusetsize == -1 || (u_long)kcpusetsize > sizeof(cpuset_t))
138 if (_kvm_pcpu_init(kd) < 0)
141 if (cpu >= maxcpu || pcpu_data[cpu] == NULL)
144 buf = malloc(sizeof(struct pcpu));
146 _kvm_err(kd, kd->program, "out of memory");
149 nbytes = sizeof(struct pcpu) - 2 * kcpusetsize;
150 readptr = (uintptr_t)pcpu_data[cpu];
151 if (kvm_read(kd, readptr, buf, nbytes) != nbytes) {
152 _kvm_err(kd, kd->program, "unable to read per-CPU data");
157 /* Fetch the valid cpuset_t objects. */
158 CPU_ZERO((cpuset_t *)(buf + nbytes));
159 CPU_ZERO((cpuset_t *)(buf + nbytes + sizeof(cpuset_t)));
161 if (kvm_read(kd, readptr, buf + nbytes, kcpusetsize) != kcpusetsize) {
162 _kvm_err(kd, kd->program, "unable to read per-CPU data");
166 readptr += kcpusetsize;
167 if (kvm_read(kd, readptr, buf + nbytes + sizeof(cpuset_t),
168 kcpusetsize) != kcpusetsize) {
169 _kvm_err(kd, kd->program, "unable to read per-CPU data");
177 kvm_getmaxcpu(kvm_t *kd)
186 if (_kvm_pcpu_init(kd) < 0)
192 _kvm_dpcpu_setcpu(kvm_t *kd, u_int cpu, int report_error)
195 if (!kd->dpcpu_initialized) {
197 _kvm_err(kd, kd->program, "%s: not initialized",
201 if (cpu >= kd->dpcpu_maxcpus) {
203 _kvm_err(kd, kd->program, "%s: CPU %u too big",
207 if (kd->dpcpu_off[cpu] == 0) {
209 _kvm_err(kd, kd->program, "%s: CPU %u not found",
213 kd->dpcpu_curcpu = cpu;
214 kd->dpcpu_curoff = kd->dpcpu_off[cpu];
219 * Set up libkvm to handle dynamic per-CPU memory.
222 _kvm_dpcpu_init(kvm_t *kd)
224 struct nlist nl[] = {
225 #define NLIST_START_SET_PCPU 0
226 { .n_name = "___start_" DPCPU_SETNAME },
227 #define NLIST_STOP_SET_PCPU 1
228 { .n_name = "___stop_" DPCPU_SETNAME },
229 #define NLIST_DPCPU_OFF 2
230 { .n_name = "_dpcpu_off" },
231 #define NLIST_MP_MAXCPUS 3
232 { .n_name = "_mp_maxcpus" },
235 uintptr_t *dpcpu_off_buf;
240 * Locate and cache locations of important symbols using the internal
241 * version of _kvm_nlist, turning off initialization to avoid
242 * recursion in case of unresolveable symbols.
244 if (_kvm_nlist(kd, nl, 0) != 0)
246 if (kvm_read(kd, nl[NLIST_MP_MAXCPUS].n_value, &dpcpu_maxcpus,
247 sizeof(dpcpu_maxcpus)) != sizeof(dpcpu_maxcpus))
249 len = dpcpu_maxcpus * sizeof(*dpcpu_off_buf);
250 dpcpu_off_buf = malloc(len);
251 if (dpcpu_off_buf == NULL)
253 if (kvm_read(kd, nl[NLIST_DPCPU_OFF].n_value, dpcpu_off_buf, len) !=
258 kd->dpcpu_start = nl[NLIST_START_SET_PCPU].n_value;
259 kd->dpcpu_stop = nl[NLIST_STOP_SET_PCPU].n_value;
260 kd->dpcpu_maxcpus = dpcpu_maxcpus;
261 kd->dpcpu_off = dpcpu_off_buf;
262 kd->dpcpu_initialized = 1;
263 (void)_kvm_dpcpu_setcpu(kd, 0, 0);
268 * Check whether the dpcpu module has been initialized sucessfully or not,
269 * initialize it if permitted.
272 _kvm_dpcpu_initialized(kvm_t *kd, int intialize)
275 if (kd->dpcpu_initialized || !intialize)
276 return (kd->dpcpu_initialized);
278 (void)_kvm_dpcpu_init(kd);
280 return (kd->dpcpu_initialized);
284 * Check whether the value is within the dpcpu symbol range and only if so
285 * adjust the offset relative to the current offset.
288 _kvm_dpcpu_validaddr(kvm_t *kd, uintptr_t value)
294 if (!kd->dpcpu_initialized)
297 if (value < kd->dpcpu_start || value >= kd->dpcpu_stop)
300 return (kd->dpcpu_curoff + value);
304 kvm_dpcpu_setcpu(kvm_t *kd, u_int cpu)
308 if (!kd->dpcpu_initialized) {
309 ret = _kvm_dpcpu_init(kd);
311 _kvm_err(kd, kd->program, "%s: init failed",
317 return (_kvm_dpcpu_setcpu(kd, cpu, 1));