1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2008 Yahoo!, Inc. 5 * All rights reserved. 6 * Written by: John Baldwin <jhb@FreeBSD.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/pcpu.h> 35 #include <sys/resource.h> 36 #include <sys/sysctl.h> 37 #include <errno.h> 38 #include <kvm.h> 39 #include <limits.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #include "kvm_private.h" 44 45 static struct nlist kvm_cp_time_nl[] = { 46 { .n_name = "_cp_time" }, /* (deprecated) */ 47 { .n_name = NULL }, 48 }; 49 50 #define NL_CP_TIME 0 51 52 static int kvm_cp_time_cached; 53 54 static int 55 _kvm_cp_time_init(kvm_t *kd) 56 { 57 58 if (kvm_nlist(kd, kvm_cp_time_nl) < 0) 59 return (-1); 60 kvm_cp_time_cached = 1; 61 return (0); 62 } 63 64 static int 65 getsysctl(kvm_t *kd, const char *name, void *buf, size_t len) 66 { 67 size_t nlen; 68 69 nlen = len; 70 if (sysctlbyname(name, buf, &nlen, NULL, 0) < 0) { 71 _kvm_err(kd, kd->program, "cannot read sysctl %s:%s", name, 72 strerror(errno)); 73 return (-1); 74 } 75 if (nlen != len) { 76 _kvm_err(kd, kd->program, "sysctl %s has unexpected size", 77 name); 78 return (-1); 79 } 80 return (0); 81 } 82 83 int 84 kvm_getcptime(kvm_t *kd, long *cp_time) 85 { 86 struct pcpu *pc; 87 int i, j, maxcpu; 88 89 if (kd == NULL) { 90 kvm_cp_time_cached = 0; 91 return (0); 92 } 93 94 if (ISALIVE(kd)) 95 return (getsysctl(kd, "kern.cp_time", cp_time, sizeof(long) * 96 CPUSTATES)); 97 98 if (!kd->arch->ka_native(kd)) { 99 _kvm_err(kd, kd->program, 100 "cannot read cp_time from non-native core"); 101 return (-1); 102 } 103 104 if (kvm_cp_time_cached == 0) { 105 if (_kvm_cp_time_init(kd) < 0) 106 return (-1); 107 } 108 109 /* If this kernel has a "cp_time[]" symbol, then just read that. */ 110 if (kvm_cp_time_nl[NL_CP_TIME].n_value != 0) { 111 if (kvm_read(kd, kvm_cp_time_nl[NL_CP_TIME].n_value, cp_time, 112 sizeof(long) * CPUSTATES) != sizeof(long) * CPUSTATES) { 113 _kvm_err(kd, kd->program, "cannot read cp_time array"); 114 return (-1); 115 } 116 return (0); 117 } 118 119 /* 120 * If we don't have that symbol, then we have to simulate 121 * "cp_time[]" by adding up the individual times for each CPU. 122 */ 123 maxcpu = kvm_getmaxcpu(kd); 124 if (maxcpu < 0) 125 return (-1); 126 for (i = 0; i < CPUSTATES; i++) 127 cp_time[i] = 0; 128 for (i = 0; i < maxcpu; i++) { 129 pc = kvm_getpcpu(kd, i); 130 if (pc == NULL) 131 continue; 132 if (pc == (void *)-1) 133 return (-1); 134 for (j = 0; j < CPUSTATES; j++) 135 cp_time[j] += pc->pc_cp_time[j]; 136 free(pc); 137 } 138 return (0); 139 } 140