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authorRabin Vincent <rabin@rab.in>2015-05-14 18:19:03 +0200
committerJesper Nilsson <jespern@axis.com>2015-09-05 00:56:50 +0200
commitaa6f4d2b6547a9949d87c9b09a872a7015366588 (patch)
tree6efb66f528d045e050b21889c31937b5b4bbadf6 /arch/cris/kernel
parent3fffa23ee0a348aef1b597b67626d4724667143b (diff)
downloadop-kernel-dev-aa6f4d2b6547a9949d87c9b09a872a7015366588.zip
op-kernel-dev-aa6f4d2b6547a9949d87c9b09a872a7015366588.tar.gz
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>
Diffstat (limited to 'arch/cris/kernel')
-rw-r--r--arch/cris/kernel/Makefile1
-rw-r--r--arch/cris/kernel/stacktrace.c76
2 files changed, 77 insertions, 0 deletions
diff --git a/arch/cris/kernel/Makefile b/arch/cris/kernel/Makefile
index edef71f..5fae398 100644
--- 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
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 */
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