CRIS: add STACKTRACE_SUPPORT

Add stacktrace support, which is required for lockdep and tracing.  The
stack tracing simply looks at all kernel text symbols found on the
stack, similar to the trap stack dumping code, which can also be
converted to use this.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>

diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig
index e7ba2d4bdd4f3bf2bde4b46c8138725f9ea197dd..61f4acceb9d43be85d5b6af6d167c11db6c10ec0 100644 (file)
--- a/arch/cris/Kconfig
+++ b/arch/cris/Kconfig
@@ -40,6 +40,9 @@ config TRACE_IRQFLAGS_SUPPORT
        depends on ETRAX_ARCH_V32
        def_bool y
 
+config STACKTRACE_SUPPORT
+       def_bool y
+
 config CRIS
        bool
        default y

diff --git a/arch/cris/include/asm/stacktrace.h b/arch/cris/include/asm/stacktrace.h
new file mode 100644 (file)
index 0000000..2d90856
--- /dev/null
+++ b/arch/cris/include/asm/stacktrace.h
@@ -0,0 +1,8 @@
+#ifndef __CRIS_STACKTRACE_H
+#define __CRIS_STACKTRACE_H
+
+void walk_stackframe(unsigned long sp,
+                    int (*fn)(unsigned long addr, void *data),
+                    void *data);
+
+#endif

diff --git a/arch/cris/kernel/Makefile b/arch/cris/kernel/Makefile
index edef71f12bb8860c147dfb1ef703d817cef33d9d..5fae398ca9152749155b4e5f3dfd0209a9cab832 100644 (file)
--- a/arch/cris/kernel/Makefile
+++ b/arch/cris/kernel/Makefile
@@ -8,6 +8,7 @@ extra-y := vmlinux.lds
 
 obj-y   := process.o traps.o irq.o ptrace.o setup.o time.o sys_cris.o
 obj-y += devicetree.o
+obj-y += stacktrace.o
 
 obj-$(CONFIG_MODULES)    += crisksyms.o
 obj-$(CONFIG_MODULES)   += module.o

diff --git a/arch/cris/kernel/stacktrace.c b/arch/cris/kernel/stacktrace.c
new file mode 100644 (file)
index 0000000..99838c7
--- /dev/null
+++ b/arch/cris/kernel/stacktrace.c
@@ -0,0 +1,76 @@
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/stacktrace.h>
+#include <asm/stacktrace.h>
+
+void walk_stackframe(unsigned long sp,
+                    int (*fn)(unsigned long addr, void *data),
+                    void *data)
+{
+       unsigned long high = ALIGN(sp, THREAD_SIZE);
+
+       for (; sp <= high - 4; sp += 4) {
+               unsigned long addr = *(unsigned long *) sp;
+
+               if (!kernel_text_address(addr))
+                       continue;
+
+               if (fn(addr, data))
+                       break;
+       }
+}
+
+struct stack_trace_data {
+       struct stack_trace *trace;
+       unsigned int no_sched_functions;
+       unsigned int skip;
+};
+
+#ifdef CONFIG_STACKTRACE
+
+static int save_trace(unsigned long addr, void *d)
+{
+       struct stack_trace_data *data = d;
+       struct stack_trace *trace = data->trace;
+
+       if (data->no_sched_functions && in_sched_functions(addr))
+               return 0;
+
+       if (data->skip) {
+               data->skip--;
+               return 0;
+       }
+
+       trace->entries[trace->nr_entries++] = addr;
+
+       return trace->nr_entries >= trace->max_entries;
+}
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+       struct stack_trace_data data;
+       unsigned long sp;
+
+       data.trace = trace;
+       data.skip = trace->skip;
+
+       if (tsk != current) {
+               data.no_sched_functions = 1;
+               sp = tsk->thread.ksp;
+       } else {
+               data.no_sched_functions = 0;
+               sp = rdsp();
+       }
+
+       walk_stackframe(sp, save_trace, &data);
+       if (trace->nr_entries < trace->max_entries)
+               trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+       save_stack_trace_tsk(current, trace);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+
+#endif /* CONFIG_STACKTRACE */