1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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/param.h> 31 #include <sys/systm.h> 32 #include <sys/pmc.h> 33 34 #include <vm/vm.h> 35 #include <vm/pmap.h> 36 37 #include <machine/cpu.h> 38 #include <machine/md_var.h> 39 #include <machine/pmc_mdep.h> 40 #include <machine/stack.h> 41 #include <machine/vmparam.h> 42 43 /* XXX: Userland code compiled with gcc will need an heuristic 44 * to be correctly detected. 45 */ 46 #ifdef __clang__ 47 #define PC_OFF 1 48 #define FP_OFF 0 49 #else 50 #define PC_OFF -1 51 #define FP_OFF -3 52 #endif 53 54 struct pmc_mdep * 55 pmc_md_initialize(void) 56 { 57 #ifdef CPU_CORTEXA 58 if (cpu_class == CPU_CLASS_CORTEXA) 59 return pmc_armv7_initialize(); 60 #endif 61 return NULL; 62 } 63 64 void 65 pmc_md_finalize(struct pmc_mdep *md) 66 { 67 #ifdef CPU_CORTEXA 68 if (cpu_class == CPU_CLASS_CORTEXA) 69 pmc_armv7_finalize(md); 70 #endif 71 } 72 73 int 74 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples, 75 struct trapframe *tf) 76 { 77 uintptr_t pc, ra, fp; 78 int count; 79 80 KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace", 81 __LINE__)); 82 83 pc = PMC_TRAPFRAME_TO_PC(tf); 84 *cc++ = pc; 85 86 if (maxsamples <= 1) 87 return (1); 88 89 fp = PMC_TRAPFRAME_TO_FP(tf); 90 if (!PMC_IN_KERNEL(pc) || !PMC_IN_KERNEL_STACK(fp)) 91 return (1); 92 93 for (count = 1; count < maxsamples; count++) { 94 /* Use saved lr as pc. */ 95 ra = fp + PC_OFF * sizeof(uintptr_t); 96 if (!PMC_IN_KERNEL_STACK(ra)) 97 break; 98 pc = *(uintptr_t *)ra; 99 if (!PMC_IN_KERNEL(pc)) 100 break; 101 102 *cc++ = pc; 103 104 /* Switch to next frame up */ 105 ra = fp + FP_OFF * sizeof(uintptr_t); 106 if (!PMC_IN_KERNEL_STACK(ra)) 107 break; 108 fp = *(uintptr_t *)ra; 109 if (!PMC_IN_KERNEL_STACK(fp)) 110 break; 111 } 112 113 return (count); 114 } 115 116 int 117 pmc_save_user_callchain(uintptr_t *cc, int maxsamples, 118 struct trapframe *tf) 119 { 120 uintptr_t pc, r, oldfp, fp; 121 int count; 122 123 KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p", 124 __LINE__, (void *) tf)); 125 126 pc = PMC_TRAPFRAME_TO_PC(tf); 127 *cc++ = pc; 128 129 if (maxsamples <= 1) 130 return (1); 131 132 oldfp = fp = PMC_TRAPFRAME_TO_FP(tf); 133 134 if (!PMC_IN_USERSPACE(pc) || 135 !PMC_IN_USERSPACE(fp)) 136 return (1); 137 138 for (count = 1; count < maxsamples; count++) { 139 /* Use saved lr as pc. */ 140 r = fp + PC_OFF * sizeof(uintptr_t); 141 if (copyin((void *)r, &pc, sizeof(pc)) != 0) 142 break; 143 if (!PMC_IN_USERSPACE(pc)) 144 break; 145 146 *cc++ = pc; 147 148 /* Switch to next frame up */ 149 oldfp = fp; 150 r = fp + FP_OFF * sizeof(uintptr_t); 151 if (copyin((void *)r, &fp, sizeof(fp)) != 0) 152 break; 153 if (fp < oldfp || !PMC_IN_USERSPACE(fp)) 154 break; 155 } 156 157 return (count); 158 } 159