1 files changed, 32 insertions, 24 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3718d55fb4c3..f3716bf04df6 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
         pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
 
  again:
-        rec++;
+        if (idx != 0)
+                rec++;
+
         if ((void *)rec >= (void *)&pg->records[pg->index]) {
                 pg = pg->next;
                 if (!pg)
@@ -1417,10 +1419,20 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
+
+        if (!(iter->flags & FTRACE_ITER_HASH))
+                *pos = 0;
 
         iter->flags |= FTRACE_ITER_HASH;
 
-        return t_hash_next(m, p, pos);
+        iter->hidx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_hash_next(m, p, &l);
+                if (!p)
+                        break;
+        }
+        return p;
 }
 
 static int t_hash_show(struct seq_file *m, void *v)
@@ -1467,8 +1479,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                         iter->pg = iter->pg->next;
                         iter->idx = 0;
                         goto retry;
-                } else {
-                        iter->idx = -1;
                 }
         } else {
                 rec = &iter->pg->records[iter->idx++];
@@ -1497,6 +1507,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
 
         mutex_lock(&ftrace_lock);
         /*
@@ -1508,23 +1519,21 @@ static void *t_start(struct seq_file *m, loff_t *pos)
                 if (*pos > 0)
                         return t_hash_start(m, pos);
                 iter->flags |= FTRACE_ITER_PRINTALL;
-                (*pos)++;
                 return iter;
         }
 
         if (iter->flags & FTRACE_ITER_HASH)
                 return t_hash_start(m, pos);
 
-        if (*pos > 0) {
-                if (iter->idx < 0)
-                        return p;
-                (*pos)--;
-                iter->idx--;
+        iter->pg = ftrace_pages_start;
+        iter->idx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_next(m, p, &l);
+                if (!p)
+                        break;
         }
 
-        p = t_next(m, p, pos);
-
-        if (!p)
+        if (!p && iter->flags & FTRACE_ITER_FILTER)
                 return t_hash_start(m, pos);
 
         return p;
@@ -2500,32 +2509,31 @@ int ftrace_graph_count;
 unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
 
 static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
 {
         unsigned long *array = m->private;
-        int index = *pos;
 
-        (*pos)++;
-
-        if (index >= ftrace_graph_count)
+        if (*pos >= ftrace_graph_count)
                 return NULL;
+        return &array[*pos];
+}
 
-        return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+        (*pos)++;
+        return __g_next(m, pos);
 }
 
 static void *g_start(struct seq_file *m, loff_t *pos)
 {
-        void *p = NULL;
-
         mutex_lock(&graph_lock);
 
         /* Nothing, tell g_show to print all functions are enabled */
         if (!ftrace_graph_count && !*pos)
                 return (void *)1;
 
-        p = g_next(m, p, pos);
-
-        return p;
+        return __g_next(m, pos);
 }
 
 static void g_stop(struct seq_file *m, void *p)