/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2005, Joseph Koshy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/pmc.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <machine/cpu.h>
#include <machine/md_var.h>
#include <machine/pmc_mdep.h>
#include <machine/stack.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
/* XXX: Userland code compiled with gcc will need an heuristic
* to be correctly detected.
*/
#ifdef __clang__
#define PC_OFF 1
#define FP_OFF 0
#else
#define PC_OFF -1
#define FP_OFF -3
#endif
struct pmc_mdep *
pmc_md_initialize()
{
#ifdef CPU_CORTEXA
if (cpu_class == CPU_CLASS_CORTEXA)
return pmc_armv7_initialize();
#endif
return NULL;
}
void
pmc_md_finalize(struct pmc_mdep *md)
{
#ifdef CPU_CORTEXA
if (cpu_class == CPU_CLASS_CORTEXA)
pmc_armv7_finalize(md);
#endif
}
int
pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
struct trapframe *tf)
{
uintptr_t pc, r, stackstart, stackend, fp;
struct thread *td;
int count;
KASSERT(TRAPF_USERMODE(tf) == 0,("[arm,%d] not a kernel backtrace",
__LINE__));
td = curthread;
pc = PMC_TRAPFRAME_TO_PC(tf);
*cc++ = pc;
if (maxsamples <= 1)
return (1);
stackstart = (uintptr_t) td->td_kstack;
stackend = (uintptr_t) td->td_kstack + td->td_kstack_pages * PAGE_SIZE;
fp = PMC_TRAPFRAME_TO_FP(tf);
if (!PMC_IN_KERNEL(pc) ||
!PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
return (1);
for (count = 1; count < maxsamples; count++) {
/* Use saved lr as pc. */
r = fp + PC_OFF * sizeof(uintptr_t);
if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
break;
pc = *(uintptr_t *)r;
if (!PMC_IN_KERNEL(pc))
break;
*cc++ = pc;
/* Switch to next frame up */
r = fp + FP_OFF * sizeof(uintptr_t);
if (!PMC_IN_KERNEL_STACK(r, stackstart, stackend))
break;
fp = *(uintptr_t *)r;
if (!PMC_IN_KERNEL_STACK(fp, stackstart, stackend))
break;
}
return (count);
}
int
pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
struct trapframe *tf)
{
uintptr_t pc, r, oldfp, fp;
struct thread *td;
int count;
KASSERT(TRAPF_USERMODE(tf), ("[x86,%d] Not a user trap frame tf=%p",
__LINE__, (void *) tf));
td = curthread;
pc = PMC_TRAPFRAME_TO_PC(tf);
*cc++ = pc;
if (maxsamples <= 1)
return (1);
oldfp = fp = PMC_TRAPFRAME_TO_FP(tf);
if (!PMC_IN_USERSPACE(pc) ||
!PMC_IN_USERSPACE(fp))
return (1);
for (count = 1; count < maxsamples; count++) {
/* Use saved lr as pc. */
r = fp + PC_OFF * sizeof(uintptr_t);
if (copyin((void *)r, &pc, sizeof(pc)) != 0)
break;
if (!PMC_IN_USERSPACE(pc))
break;
*cc++ = pc;
/* Switch to next frame up */
oldfp = fp;
r = fp + FP_OFF * sizeof(uintptr_t);
if (copyin((void *)r, &fp, sizeof(fp)) != 0)
break;
if (fp < oldfp || !PMC_IN_USERSPACE(fp))
break;
}
return (count);
}
