1 /*- 2 * Copyright (c) 2008 Yahoo!, 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 * 3. 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 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include <sys/param.h> 35 #include <sys/pcpu.h> 36 #include <sys/resource.h> 37 #include <sys/sysctl.h> 38 #include <errno.h> 39 #include <kvm.h> 40 #include <limits.h> 41 #include <stdlib.h> 42 #include <string.h> 43 44 #include "kvm_private.h" 45 46 static struct nlist kvm_cp_time_nl[] = { 47 { .n_name = "_cp_time" }, /* (deprecated) */ 48 { .n_name = NULL }, 49 }; 50 51 #define NL_CP_TIME 0 52 53 static int kvm_cp_time_cached; 54 55 static int 56 _kvm_cp_time_init(kvm_t *kd) 57 { 58 59 if (kvm_nlist(kd, kvm_cp_time_nl) < 0) 60 return (-1); 61 kvm_cp_time_cached = 1; 62 return (0); 63 } 64 65 static int 66 getsysctl(kvm_t *kd, const char *name, void *buf, size_t len) 67 { 68 size_t nlen; 69 70 nlen = len; 71 if (sysctlbyname(name, buf, &nlen, NULL, 0) < 0) { 72 _kvm_err(kd, kd->program, "cannot read sysctl %s:%s", name, 73 strerror(errno)); 74 return (-1); 75 } 76 if (nlen != len) { 77 _kvm_err(kd, kd->program, "sysctl %s has unexpected size", 78 name); 79 return (-1); 80 } 81 return (0); 82 } 83 84 int 85 kvm_getcptime(kvm_t *kd, long *cp_time) 86 { 87 struct pcpu *pc; 88 int i, j, maxcpu; 89 90 if (kd == NULL) { 91 kvm_cp_time_cached = 0; 92 return (0); 93 } 94 95 if (ISALIVE(kd)) 96 return (getsysctl(kd, "kern.cp_time", cp_time, sizeof(long) * 97 CPUSTATES)); 98 99 if (kvm_cp_time_cached == 0) { 100 if (_kvm_cp_time_init(kd) < 0) 101 return (-1); 102 } 103 104 /* If this kernel has a "cp_time[]" symbol, then just read that. */ 105 if (kvm_cp_time_nl[NL_CP_TIME].n_value != 0) { 106 if (kvm_read(kd, kvm_cp_time_nl[NL_CP_TIME].n_value, cp_time, 107 sizeof(long) * CPUSTATES) != sizeof(long) * CPUSTATES) { 108 _kvm_err(kd, kd->program, "cannot read cp_time array"); 109 return (-1); 110 } 111 return (0); 112 } 113 114 /* 115 * If we don't have that symbol, then we have to simulate 116 * "cp_time[]" by adding up the individual times for each CPU. 117 */ 118 maxcpu = kvm_getmaxcpu(kd); 119 if (maxcpu < 0) 120 return (-1); 121 for (i = 0; i < CPUSTATES; i++) 122 cp_time[i] = 0; 123 for (i = 0; i < maxcpu; i++) { 124 pc = kvm_getpcpu(kd, i); 125 if (pc == NULL) 126 continue; 127 if (pc == (void *)-1) 128 return (-1); 129 for (j = 0; j < CPUSTATES; j++) 130 cp_time[j] += pc->pc_cp_time[j]; 131 free(pc); 132 } 133 return (0); 134 } 135