ftrace: nmi safe code clean ups

Impact: cleanup

This patch cleans up the NMI safe code for dynamic ftrace as suggested
by Andrew Morton.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 5 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bc36febc0771..7f86067d760c 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2815,10 +2815,6 @@ static struct file_operations tracing_mark_fops = {
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 
-#define DYN_INFO_BUF_SIZE 1023
-static char ftrace_dyn_info_buffer[DYN_INFO_BUF_SIZE+1];
-static DEFINE_MUTEX(dyn_info_mutex);
-
 int __weak ftrace_arch_read_dyn_info(char *buf, int size)
 {
         return 0;
@@ -2828,14 +2824,17 @@ static ssize_t
 tracing_read_dyn_info(struct file *filp, char __user *ubuf,
                   size_t cnt, loff_t *ppos)
 {
+        static char ftrace_dyn_info_buffer[1024];
+        static DEFINE_MUTEX(dyn_info_mutex);
         unsigned long *p = filp->private_data;
         char *buf = ftrace_dyn_info_buffer;
+        int size = ARRAY_SIZE(ftrace_dyn_info_buffer);
         int r;
 
         mutex_lock(&dyn_info_mutex);
         r = sprintf(buf, "%ld ", *p);
 
-        r += ftrace_arch_read_dyn_info(buf+r, DYN_INFO_BUF_SIZE-r);
+        r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r);
         buf[r++] = '\n';
 
         r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);