ftrace: build fix

no need to backmerge, only affects ftrace-enabled kernels. (which is
not the default)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 6974b212e938..958c4d77a67b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1965,7 +1965,9 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
         static cpumask_t mask;
         static int start;
         unsigned long flags;
+#ifdef CONFIG_FTRACE
         int ftrace_save;
+#endif
         int read = 0;
         int cpu;
         int len;
@@ -2044,8 +2046,10 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
 
         cpus_clear(mask);
         local_irq_save(flags);
+#ifdef CONFIG_FTRACE
         ftrace_save = ftrace_enabled;
         ftrace_enabled = 0;
+#endif
         smp_wmb();
         for_each_possible_cpu(cpu) {
                 data = iter->tr->data[cpu];
@@ -2087,7 +2091,9 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
                 data = iter->tr->data[cpu];
                 atomic_dec(&data->disabled);
         }
+#ifdef CONFIG_FTRACE
         ftrace_enabled = ftrace_save;
+#endif
         local_irq_restore(flags);
 
         /* Now copy what we have to the user */