sys/dev/hwpmc/hwpmc_arm.c

   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_XSCALE_IXP425
  62         if (cpu_class == CPU_CLASS_XSCALE)
  63                 return pmc_xscale_initialize();
  64 #endif
  65 #ifdef CPU_CORTEXA
  66         if (cpu_class == CPU_CLASS_CORTEXA)
  67                 return pmc_armv7_initialize();
  68 #endif
  69         return NULL;
  70 }
  71
  72 void
  73 pmc_md_finalize(struct pmc_mdep *md)
  74 {
  75 #ifdef CPU_XSCALE_IXP425
  76         if (cpu_class == CPU_CLASS_XSCALE)
  77                 pmc_xscale_finalize(md);
  78         else
  79                 KASSERT(0, ("[arm,%d] Unknown CPU Class 0x%x", __LINE__,
  80                     cpu_class));
  81 #endif
  82 #ifdef CPU_CORTEXA
  83         if (cpu_class == CPU_CLASS_CORTEXA)
  84                 pmc_armv7_finalize(md);
  85 #endif
  86 }
  87
  88 int
  89 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
  90     struct trapframe *tf)
  91 {
  92         uintptr_t pc, r, stackstart, stackend, fp;
  93         struct thread *td;
  94         int count;
  95
  96         KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace",
  97             __LINE__));
  98
  99         td = curthread;
 100         pc = PMC_TRAPFRAME_TO_PC(tf);
 101         *cc++ = pc;
 102
 103         if (maxsamples <= 1)
 104                 return (1);
 105
 106         stackstart = (uintptr_t) td->td_kstack;
 107         stackend = (uintptr_t) td->td_kstack + td->td_kstack_pages * PAGE_SIZE;
 108         fp = PMC_TRAPFRAME_TO_FP(tf);
 109
 110         if (!PMC_IN_KERNEL(pc) ||
 111             !PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
 112                 return (1);
 113
 114         for (count = 1; count < maxsamples; count++) {
 115                 /* Use saved lr as pc. */
 116                 r = fp + PC_OFF * sizeof(uintptr_t);
 117                 if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
 118                         break;
 119                 pc = *(uintptr_t *)r;
 120                 if (!PMC_IN_KERNEL(pc))
 121                         break;
 122
 123                 *cc++ = pc;
 124
 125                 /* Switch to next frame up */
 126                 r = fp + FP_OFF * sizeof(uintptr_t);
 127                 if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
 128                         break;
 129                 fp = *(uintptr_t *)r;
 130                 if (!PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
 131                         break;
 132         }
 133
 134         return (count);
 135 }
 136
 137 int
 138 pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
 139     struct trapframe *tf)
 140 {
 141         uintptr_t pc, r, oldfp, fp;
 142         struct thread *td;
 143         int count;
 144
 145         KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p",
 146             __LINE__, (void *) tf));
 147
 148         td = curthread;
 149         pc = PMC_TRAPFRAME_TO_PC(tf);
 150         *cc++ = pc;
 151
 152         if (maxsamples <= 1)
 153                 return (1);
 154
 155         oldfp = fp = PMC_TRAPFRAME_TO_FP(tf);
 156
 157         if (!PMC_IN_USERSPACE(pc) ||
 158             !PMC_IN_USERSPACE(fp))
 159                 return (1);
 160
 161         for (count = 1; count < maxsamples; count++) {
 162                 /* Use saved lr as pc. */
 163                 r = fp + PC_OFF * sizeof(uintptr_t);
 164                 if (copyin((void *)r, &pc, sizeof(pc)) != 0)
 165                         break;
 166                 if (!PMC_IN_USERSPACE(pc))
 167                         break;
 168
 169                 *cc++ = pc;
 170
 171                 /* Switch to next frame up */
 172                 oldfp = fp;
 173                 r = fp + FP_OFF * sizeof(uintptr_t);
 174                 if (copyin((void *)r, &fp, sizeof(fp)) != 0)
 175                         break;
 176                 if (fp < oldfp || !PMC_IN_USERSPACE(fp))
 177                         break;
 178         }
 179
 180         return (count);
 181 }