From 068048faa53b96265855dba5175f0a2df1497864 Mon Sep 17 00:00:00 2001 From: Jon Medhurst Date: Thu, 10 May 2012 17:30:53 +0100 Subject: gator: Version 5.10 New gator release (build 1385) for ARM DS-5 v5.10 Signed-off-by: Jon Medhurst --- drivers/gator/gator_backtrace.c | 114 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 drivers/gator/gator_backtrace.c (limited to 'drivers/gator/gator_backtrace.c') diff --git a/drivers/gator/gator_backtrace.c b/drivers/gator/gator_backtrace.c new file mode 100644 index 00000000000..50783d69594 --- /dev/null +++ b/drivers/gator/gator_backtrace.c @@ -0,0 +1,114 @@ +/** + * Copyright (C) ARM Limited 2010-2012. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +/* + * EABI backtrace stores {fp,lr} on the stack. + */ +struct frame_tail_eabi { + unsigned long fp; // points to prev_lr + unsigned long lr; +}; + +static void arm_backtrace_eabi(int cpu, int buftype, struct pt_regs * const regs, unsigned int depth) +{ +#if defined(__arm__) + struct frame_tail_eabi *tail; + struct frame_tail_eabi *next; + struct frame_tail_eabi *ptrtail; + struct frame_tail_eabi buftail; + unsigned long fp = regs->ARM_fp; + unsigned long sp = regs->ARM_sp; + unsigned long lr = regs->ARM_lr; + int is_user_mode = user_mode(regs); + + if (!is_user_mode) { + return; + } + + /* entry preamble may not have executed */ + gator_add_trace(cpu, buftype, lr); + + /* check tail is valid */ + if (fp == 0 || fp < sp) { + return; + } + + tail = (struct frame_tail_eabi *)(fp - 4); + + while (depth-- && tail && !((unsigned long) tail & 3)) { + /* Also check accessibility of one struct frame_tail beyond */ + if (!access_ok(VERIFY_READ, tail, sizeof(struct frame_tail_eabi))) + return; + if (__copy_from_user_inatomic(&buftail, tail, sizeof(struct frame_tail_eabi))) + return; + ptrtail = &buftail; + + lr = ptrtail[0].lr; + gator_add_trace(cpu, buftype, lr); + + /* frame pointers should progress back up the stack, towards higher addresses */ + next = (struct frame_tail_eabi *)(lr - 4); + if (tail >= next || lr == 0) { + fp = ptrtail[0].fp; + next = (struct frame_tail_eabi *)(fp - 4); + /* check tail is valid */ + if (tail >= next || fp == 0) { + return; + } + } + + tail = next; + } +#endif +} + +#if defined(__arm__) +static DEFINE_PER_CPU(int, backtrace_buffer); +static int report_trace(struct stackframe *frame, void *d) +{ + struct module *mod; + unsigned int *depth = d, addr = frame->pc, cookie = NO_COOKIE, cpu = smp_processor_id(); + + if (*depth) { + mod = __module_address(addr); + if (mod) { + cookie = get_cookie(cpu, per_cpu(backtrace_buffer, cpu), current, NULL, mod, true); + addr = addr - (unsigned long)mod->module_core; + } + marshal_backtrace(addr & ~1, cookie); + (*depth)--; + } + + return *depth == 0; +} +#endif + +// Uncomment the following line to enable kernel stack unwinding within gator, note it can also be defined from the Makefile +// #define GATOR_KERNEL_STACK_UNWINDING +static void kernel_backtrace(int cpu, int buftype, struct pt_regs * const regs) +{ +#if defined(__arm__) +#ifdef GATOR_KERNEL_STACK_UNWINDING + int depth = gator_backtrace_depth; +#else + int depth = 1; +#endif + struct stackframe frame; + if (depth == 0) + depth = 1; + frame.fp = regs->ARM_fp; + frame.sp = regs->ARM_sp; + frame.lr = regs->ARM_lr; + frame.pc = regs->ARM_pc; + per_cpu(backtrace_buffer, cpu) = buftype; + walk_stackframe(&frame, report_trace, &depth); +#else + marshal_backtrace(PC_REG & ~1, NO_COOKIE); +#endif +} -- cgit v1.2.3