1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005, Joseph Koshy 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/pmc.h> 35 #include <sys/proc.h> 36 #include <sys/systm.h> 37 38 #include <machine/cpu.h> 39 #include <machine/md_var.h> 40 #include <machine/pmc_mdep.h> 41 #include <machine/stack.h> 42 43 #include <vm/vm.h> 44 #include <vm/vm_param.h> 45 #include <vm/pmap.h> 46 47 /* XXX: Userland code compiled with gcc will need an heuristic 48 * to be correctly detected. 49 */ 50 #ifdef __clang__ 51 #define PC_OFF 1 52 #define FP_OFF 0 53 #else 54 #define PC_OFF -1 55 #define FP_OFF -3 56 #endif 57 58 struct pmc_mdep * 59 pmc_md_initialize() 60 { 61 #ifdef CPU_CORTEXA 62 if (cpu_class == CPU_CLASS_CORTEXA) 63 return pmc_armv7_initialize(); 64 #endif 65 return NULL; 66 } 67 68 void 69 pmc_md_finalize(struct pmc_mdep *md) 70 { 71 #ifdef CPU_CORTEXA 72 if (cpu_class == CPU_CLASS_CORTEXA) 73 pmc_armv7_finalize(md); 74 #endif 75 } 76 77 int 78 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples, 79 struct trapframe *tf) 80 { 81 uintptr_t pc, r, stackstart, stackend, fp; 82 struct thread *td; 83 int count; 84 85 KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace", 86 __LINE__)); 87 88 td = curthread; 89 pc = PMC_TRAPFRAME_TO_PC(tf); 90 *cc++ = pc; 91 92 if (maxsamples <= 1) 93 return (1); 94 95 stackstart = (uintptr_t) td->td_kstack; 96 stackend = (uintptr_t) td->td_kstack + td->td_kstack_pages * PAGE_SIZE; 97 fp = PMC_TRAPFRAME_TO_FP(tf); 98 99 if (!PMC_IN_KERNEL(pc) || 100 !PMC_IN_KERNEL_STACK(fp, stackstart, stackend)) 101 return (1); 102 103 for (count = 1; count < maxsamples; count++) { 104 /* Use saved lr as pc. */ 105 r = fp + PC_OFF * sizeof(uintptr_t); 106 if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend)) 107 break; 108 pc = *(uintptr_t *)r; 109 if (!PMC_IN_KERNEL(pc)) 110 break; 111 112 *cc++ = pc; 113 114 /* Switch to next frame up */ 115 r = fp + FP_OFF * sizeof(uintptr_t); 116 if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend)) 117 break; 118 fp = *(uintptr_t *)r; 119 if (!PMC_IN_KERNEL_STACK(fp, stackstart, stackend)) 120 break; 121 } 122 123 return (count); 124 } 125 126 int 127 pmc_save_user_callchain(uintptr_t *cc, int maxsamples, 128 struct trapframe *tf) 129 { 130 uintptr_t pc, r, oldfp, fp; 131 int count; 132 133 KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p", 134 __LINE__, (void *) tf)); 135 136 pc = PMC_TRAPFRAME_TO_PC(tf); 137 *cc++ = pc; 138 139 if (maxsamples <= 1) 140 return (1); 141 142 oldfp = fp = PMC_TRAPFRAME_TO_FP(tf); 143 144 if (!PMC_IN_USERSPACE(pc) || 145 !PMC_IN_USERSPACE(fp)) 146 return (1); 147 148 for (count = 1; count < maxsamples; count++) { 149 /* Use saved lr as pc. */ 150 r = fp + PC_OFF * sizeof(uintptr_t); 151 if (copyin((void *)r, &pc, sizeof(pc)) != 0) 152 break; 153 if (!PMC_IN_USERSPACE(pc)) 154 break; 155 156 *cc++ = pc; 157 158 /* Switch to next frame up */ 159 oldfp = fp; 160 r = fp + FP_OFF * sizeof(uintptr_t); 161 if (copyin((void *)r, &fp, sizeof(fp)) != 0) 162 break; 163 if (fp < oldfp || !PMC_IN_USERSPACE(fp)) 164 break; 165 } 166 167 return (count); 168 } 169