Merge branch 'linus' into release

Conflicts:
	arch/x86/kernel/cpu/cpufreq/longhaul.c

Signed-off-by: Len Brown <len.brown@intel.com>

3 files changed, 80 insertions, 6 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 34e707e5ab87..504086ab4443 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -72,11 +72,10 @@ config FUNCTION_GRAPH_TRACER
         help
           Enable the kernel to trace a function at both its return
           and its entry.
-          It's first purpose is to trace the duration of functions and
-          draw a call graph for each thread with some informations like
-          the return value.
-          This is done by setting the current return address on the current
-          task structure into a stack of calls.
+          Its first purpose is to trace the duration of functions and
+          draw a call graph for each thread with some information like
+          the return value. This is done by setting the current return 
+          address on the current task structure into a stack of calls.
 
 config IRQSOFF_TRACER
         bool "Interrupts-off Latency Tracer"
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fdf913dfc7e8..53e8c8bc0c98 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1908,7 +1908,7 @@ int register_ftrace_function(struct ftrace_ops *ops)
 }
 
 /**
- * unregister_ftrace_function - unresgister a function for profiling.
+ * unregister_ftrace_function - unregister a function for profiling.
  * @ops - ops structure that holds the function to unregister
  *
  * Unregister a function that was added to be called by ftrace profiling.
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 930c08e5b38e..dce71a5b51bc 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -42,6 +42,81 @@ static struct tracer_flags tracer_flags = {
 /* pid on the last trace processed */
 static pid_t last_pid[NR_CPUS] = { [0 ... NR_CPUS-1] = -1 };
 
+/* Add a function return address to the trace stack on thread info.*/
+int
+ftrace_push_return_trace(unsigned long ret, unsigned long long time,
+                         unsigned long func, int *depth)
+{
+        int index;
+
+        if (!current->ret_stack)
+                return -EBUSY;
+
+        /* The return trace stack is full */
+        if (current->curr_ret_stack == FTRACE_RETFUNC_DEPTH - 1) {
+                atomic_inc(&current->trace_overrun);
+                return -EBUSY;
+        }
+
+        index = ++current->curr_ret_stack;
+        barrier();
+        current->ret_stack[index].ret = ret;
+        current->ret_stack[index].func = func;
+        current->ret_stack[index].calltime = time;
+        *depth = index;
+
+        return 0;
+}
+
+/* Retrieve a function return address to the trace stack on thread info.*/
+void
+ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
+{
+        int index;
+
+        index = current->curr_ret_stack;
+
+        if (unlikely(index < 0)) {
+                ftrace_graph_stop();
+                WARN_ON(1);
+                /* Might as well panic, otherwise we have no where to go */
+                *ret = (unsigned long)panic;
+                return;
+        }
+
+        *ret = current->ret_stack[index].ret;
+        trace->func = current->ret_stack[index].func;
+        trace->calltime = current->ret_stack[index].calltime;
+        trace->overrun = atomic_read(&current->trace_overrun);
+        trace->depth = index;
+        barrier();
+        current->curr_ret_stack--;
+
+}
+
+/*
+ * Send the trace to the ring-buffer.
+ * @return the original return address.
+ */
+unsigned long ftrace_return_to_handler(void)
+{
+        struct ftrace_graph_ret trace;
+        unsigned long ret;
+
+        ftrace_pop_return_trace(&trace, &ret);
+        trace.rettime = cpu_clock(raw_smp_processor_id());
+        ftrace_graph_return(&trace);
+
+        if (unlikely(!ret)) {
+                ftrace_graph_stop();
+                WARN_ON(1);
+                /* Might as well panic. What else to do? */
+                ret = (unsigned long)panic;
+        }
+
+        return ret;
+}
+
 static int graph_trace_init(struct trace_array *tr)
 {
         int cpu, ret;