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/cdefs.h> 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/pmc.h> 34 35 #include <vm/vm.h> 36 #include <vm/pmap.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 #include <machine/vmparam.h> 43 44 /* XXX: Userland code compiled with gcc will need an heuristic 45 * to be correctly detected. 46 */ 47 #ifdef __clang__ 48 #define PC_OFF 1 49 #define FP_OFF 0 50 #else 51 #define PC_OFF -1 52 #define FP_OFF -3 53 #endif 54 55 struct pmc_mdep * 56 pmc_md_initialize(void) 57 { 58 #ifdef CPU_CORTEXA 59 if (cpu_class == CPU_CLASS_CORTEXA) 60 return pmc_armv7_initialize(); 61 #endif 62 return NULL; 63 } 64 65 void 66 pmc_md_finalize(struct pmc_mdep *md) 67 { 68 #ifdef CPU_CORTEXA 69 if (cpu_class == CPU_CLASS_CORTEXA) 70 pmc_armv7_finalize(md); 71 #endif 72 } 73 74 int 75 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples, 76 struct trapframe *tf) 77 { 78 uintptr_t pc, ra, fp; 79 int count; 80 81 KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace", 82 __LINE__)); 83 84 pc = PMC_TRAPFRAME_TO_PC(tf); 85 *cc++ = pc; 86 87 if (maxsamples <= 1) 88 return (1); 89 90 fp = PMC_TRAPFRAME_TO_FP(tf); 91 if (!PMC_IN_KERNEL(pc) || !PMC_IN_KERNEL_STACK(fp)) 92 return (1); 93 94 for (count = 1; count < maxsamples; count++) { 95 /* Use saved lr as pc. */ 96 ra = fp + PC_OFF * sizeof(uintptr_t); 97 if (!PMC_IN_KERNEL_STACK(ra)) 98 break; 99 pc = *(uintptr_t *)ra; 100 if (!PMC_IN_KERNEL(pc)) 101 break; 102 103 *cc++ = pc; 104 105 /* Switch to next frame up */ 106 ra = fp + FP_OFF * sizeof(uintptr_t); 107 if (!PMC_IN_KERNEL_STACK(ra)) 108 break; 109 fp = *(uintptr_t *)ra; 110 if (!PMC_IN_KERNEL_STACK(fp)) 111 break; 112 } 113 114 return (count); 115 } 116 117 int 118 pmc_save_user_callchain(uintptr_t *cc, int maxsamples, 119 struct trapframe *tf) 120 { 121 uintptr_t pc, r, oldfp, fp; 122 int count; 123 124 KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p", 125 __LINE__, (void *) tf)); 126 127 pc = PMC_TRAPFRAME_TO_PC(tf); 128 *cc++ = pc; 129 130 if (maxsamples <= 1) 131 return (1); 132 133 oldfp = fp = PMC_TRAPFRAME_TO_FP(tf); 134 135 if (!PMC_IN_USERSPACE(pc) || 136 !PMC_IN_USERSPACE(fp)) 137 return (1); 138 139 for (count = 1; count < maxsamples; count++) { 140 /* Use saved lr as pc. */ 141 r = fp + PC_OFF * sizeof(uintptr_t); 142 if (copyin((void *)r, &pc, sizeof(pc)) != 0) 143 break; 144 if (!PMC_IN_USERSPACE(pc)) 145 break; 146 147 *cc++ = pc; 148 149 /* Switch to next frame up */ 150 oldfp = fp; 151 r = fp + FP_OFF * sizeof(uintptr_t); 152 if (copyin((void *)r, &fp, sizeof(fp)) != 0) 153 break; 154 if (fp < oldfp || !PMC_IN_USERSPACE(fp)) 155 break; 156 } 157 158 return (count); 159 } 160