[AVR32] Implement stacktrace support

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>

[AVR32] Implement stacktrace support
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Haavard Skinnemoen
1 parent 58bd2bfebd
Showing 3 changed files with 57 additions and 0 deletions Side-by-side Diff
arch/avr32/Kconfig
arch/avr32/kernel/Makefile
arch/avr32/kernel/stacktrace.c
@@ -24,6 +24,9 @@
 config GENERIC_HARDIRQS
 	def_bool y
  
+config STACKTRACE_SUPPORT
+	def_bool y
+
 config HARDIRQS_SW_RESEND
 	def_bool y
  
@@ -11,4 +11,5 @@
 obj-y				+= init_task.o switch_to.o cpu.o
 obj-$(CONFIG_MODULES)		+= module.o avr32_ksyms.o
 obj-$(CONFIG_KPROBES)		+= kprobes.o
+obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
+/*
+ * Stack trace management functions
+ *
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/thread_info.h>
+
+register unsigned long current_frame_pointer asm("r7");
+
+struct stackframe {
+	unsigned long lr;
+	unsigned long fp;
+};
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+void save_stack_trace(struct stack_trace *trace)
+{
+	unsigned long low, high;
+	unsigned long fp;
+	struct stackframe *frame;
+	int skip = trace->skip;
+
+	low = (unsigned long)task_stack_page(current);
+	high = low + THREAD_SIZE;
+	fp = current_frame_pointer;
+
+	while (fp >= low && fp <= (high - 8)) {
+		frame = (struct stackframe *)fp;
+
+		if (skip) {
+			skip--;
+		} else {
+			trace->entries[trace->nr_entries++] = frame->lr;
+			if (trace->nr_entries >= trace->max_entries)
+				break;
+		}
+
+		/*
+		 * The next frame must be at a higher address than the
+		 * current frame.
+		 */
+		low = fp + 8;
+		fp = frame->fp;
+	}
+}
...	...	@@ -24,6 +24,9 @@
24	24	config GENERIC_HARDIRQS
25	25	def_bool y
26	26
	27	+config STACKTRACE_SUPPORT
	28	+ def_bool y
	29	+
27	30	config HARDIRQS_SW_RESEND
28	31	def_bool y
29	32
...	...	@@ -11,4 +11,5 @@
11	11	obj-y += init_task.o switch_to.o cpu.o
12	12	obj-$(CONFIG_MODULES) += module.o avr32_ksyms.o
13	13	obj-$(CONFIG_KPROBES) += kprobes.o
	14	+obj-$(CONFIG_STACKTRACE) += stacktrace.o
	1	+/*
	2	+ * Stack trace management functions
	3	+ *
	4	+ * Copyright (C) 2007 Atmel Corporation
	5	+ *
	6	+ * This program is free software; you can redistribute it and/or modify
	7	+ * it under the terms of the GNU General Public License version 2 as
	8	+ * published by the Free Software Foundation.
	9	+ */
	10	+#include <linux/sched.h>
	11	+#include <linux/stacktrace.h>
	12	+#include <linux/thread_info.h>
	13	+
	14	+register unsigned long current_frame_pointer asm("r7");
	15	+
	16	+struct stackframe {
	17	+ unsigned long lr;
	18	+ unsigned long fp;
	19	+};
	20	+
	21	+/*
	22	+ * Save stack-backtrace addresses into a stack_trace buffer.
	23	+ */
	24	+void save_stack_trace(struct stack_trace *trace)
	25	+{
	26	+ unsigned long low, high;
	27	+ unsigned long fp;
	28	+ struct stackframe *frame;
	29	+ int skip = trace->skip;
	30	+
	31	+ low = (unsigned long)task_stack_page(current);
	32	+ high = low + THREAD_SIZE;
	33	+ fp = current_frame_pointer;
	34	+
	35	+ while (fp >= low && fp <= (high - 8)) {
	36	+ frame = (struct stackframe *)fp;
	37	+
	38	+ if (skip) {
	39	+ skip--;
	40	+ } else {
	41	+ trace->entries[trace->nr_entries++] = frame->lr;
	42	+ if (trace->nr_entries >= trace->max_entries)
	43	+ break;
	44	+ }
	45	+
	46	+ /*
	47	+ * The next frame must be at a higher address than the
	48	+ * current frame.
	49	+ */
	50	+ low = fp + 8;
	51	+ fp = frame->fp;
	52	+ }
	53	+}