Add kernel support for oprofile callgraphs on AVR32 (3d256151) · Commits · 戴 / test

arch/avr32/oprofile/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -5,4 +5,4 @@ oprofile-y := $(addprefix ../../../drivers/oprofile/, \
		event_buffer.o oprofile_files.o \
		oprofilefs.o oprofile_stats.o \
		timer_int.o)
		oprofile-y += op_model_avr32.o
		oprofile-y += op_model_avr32.o backtrace.o

arch/avr32/oprofile/backtrace.c

0 → 100644

+81 −0

Original line number	Diff line number	Diff line
		/*
		* AVR32 specific backtracing code for oprofile
		*
		* Copyright 2008 Weinmann GmbH
		*
		* Author: Nikolaus Voss <n.voss@weinmann.de>
		*
		* Based on i386 oprofile backtrace code by John Levon and David Smith
		*
		* 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.
		*
		*/

		#include <linux/oprofile.h>
		#include <linux/sched.h>
		#include <linux/uaccess.h>

		/* The first two words of each frame on the stack look like this if we have
		* frame pointers */
		struct frame_head {
		unsigned long lr;
		struct frame_head *fp;
		};

		/* copied from arch/avr32/kernel/process.c */
		static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p)
		{
		return (p > (unsigned long)tinfo)
		&& (p < (unsigned long)tinfo + THREAD_SIZE - 3);
		}

		/* copied from arch/x86/oprofile/backtrace.c */
		static struct frame_head dump_user_backtrace(struct frame_head head)
		{
		struct frame_head bufhead[2];

		/* Also check accessibility of one struct frame_head beyond */
		if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
		return NULL;
		if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
		return NULL;

		oprofile_add_trace(bufhead[0].lr);

		/* frame pointers should strictly progress back up the stack
		* (towards higher addresses) */
		if (bufhead[0].fp <= head)
		return NULL;

		return bufhead[0].fp;
		}

		void avr32_backtrace(struct pt_regs * const regs, unsigned int depth)
		{
		/* Get first frame pointer */
		struct frame_head head = (struct frame_head )(regs->r7);

		if (!user_mode(regs)) {
		#ifdef CONFIG_FRAME_POINTER
		/*
		* Traverse the kernel stack from frame to frame up to
		* "depth" steps.
		*/
		while (depth-- && valid_stack_ptr(task_thread_info(current),
		(unsigned long)head)) {
		oprofile_add_trace(head->lr);
		if (head->fp <= head)
		break;
		head = head->fp;
		}
		#endif
		} else {
		/* Assume we have frame pointers in user mode process */
		while (depth-- && head)
		head = dump_user_backtrace(head);
		}
		}

arch/avr32/oprofile/op_model_avr32.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -22,6 +22,8 @@
		#define AVR32_PERFCTR_IRQ_GROUP 0
		#define AVR32_PERFCTR_IRQ_LINE 1

		void avr32_backtrace(struct pt_regs * const regs, unsigned int depth);

		enum { PCCNT, PCNT0, PCNT1, NR_counter };

		struct avr32_perf_counter {
		@@ -223,6 +225,8 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
		memcpy(ops, &avr32_perf_counter_ops,
		sizeof(struct oprofile_operations));

		ops->backtrace = avr32_backtrace;

		printk(KERN_INFO "oprofile: using AVR32 performance monitoring.\n");

		return 0;

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