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Viewing changes to arch/hexagon/kernel/stacktrace.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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arch/hexagon/kernel/stacktrace.c
 
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/*
 
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 * Stacktrace support for Hexagon
 
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 *
 
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 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
 
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 *
 
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 * This program is free software; you can redistribute it and/or modify
 
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 * it under the terms of the GNU General Public License version 2 and
 
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 * only version 2 as published by the Free Software Foundation.
 
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 *
 
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 * This program is distributed in the hope that it will be useful,
 
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 
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 * GNU General Public License for more details.
 
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 *
 
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 * You should have received a copy of the GNU General Public License
 
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 * along with this program; if not, write to the Free Software
 
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 
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 * 02110-1301, USA.
 
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 */
 
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#include <linux/sched.h>
 
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#include <linux/stacktrace.h>
 
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#include <linux/thread_info.h>
 
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#include <linux/module.h>
 
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register unsigned long current_frame_pointer asm("r30");
 
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struct stackframe {
 
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        unsigned long fp;
 
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        unsigned long rets;
 
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};
 
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/*
 
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 * Save stack-backtrace addresses into a stack_trace buffer.
 
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 */
 
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void save_stack_trace(struct stack_trace *trace)
 
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{
 
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        unsigned long low, high;
 
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        unsigned long fp;
 
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        struct stackframe *frame;
 
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        int skip = trace->skip;
 
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        low = (unsigned long)task_stack_page(current);
 
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        high = low + THREAD_SIZE;
 
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        fp = current_frame_pointer;
 
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        while (fp >= low && fp <= (high - sizeof(*frame))) {
 
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                frame = (struct stackframe *)fp;
 
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                if (skip) {
 
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                        skip--;
 
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                } else {
 
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                        trace->entries[trace->nr_entries++] = frame->rets;
 
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                        if (trace->nr_entries >= trace->max_entries)
 
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                                break;
 
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                }
 
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                /*
 
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                 * The next frame must be at a higher address than the
 
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                 * current frame.
 
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                 */
 
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                low = fp + sizeof(*frame);
 
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                fp = frame->fp;
 
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        }
 
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}
 
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EXPORT_SYMBOL_GPL(save_stack_trace);