ftrace: Assign iter->hash to filter or notrace hashes on seq read

Instead of testing if the hash to use is the filter_hash or the notrace_hash
at each iteration, do the test at open, and set the iter->hash to point to
the corresponding filter or notrace hash. Then use that directly instead of
testing which hash needs to be used each iteration.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 527c4d3e8d7f8e4d0f5e017389f04fedf3bc6f79..3165b7f840e6cf94aa6aff5f5f44d98995106d4e 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3157,7 +3157,6 @@ static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
        struct ftrace_iterator *iter = m->private;
-       struct ftrace_ops *ops = iter->ops;
        struct dyn_ftrace *rec = NULL;
 
        if (unlikely(ftrace_disabled))
@@ -3181,11 +3180,8 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                }
        } else {
                rec = &iter->pg->records[iter->idx++];
-               if (((iter->flags & FTRACE_ITER_FILTER) &&
-                    !(ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))) ||
-
-                   ((iter->flags & FTRACE_ITER_NOTRACE) &&
-                    !ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) ||
+               if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) &&
+                    !ftrace_lookup_ip(iter->hash, rec->ip)) ||
 
                    ((iter->flags & FTRACE_ITER_ENABLED) &&
                     !(rec->flags & FTRACE_FL_ENABLED))) {
@@ -3213,7 +3209,6 @@ static void reset_iter_read(struct ftrace_iterator *iter)
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
        struct ftrace_iterator *iter = m->private;
-       struct ftrace_ops *ops = iter->ops;
        void *p = NULL;
        loff_t l;
 
@@ -3233,10 +3228,8 @@ static void *t_start(struct seq_file *m, loff_t *pos)
         * off, we can short cut and just print out that all
         * functions are enabled.
         */
-       if ((iter->flags & FTRACE_ITER_FILTER &&
-            ftrace_hash_empty(ops->func_hash->filter_hash)) ||
-           (iter->flags & FTRACE_ITER_NOTRACE &&
-            ftrace_hash_empty(ops->func_hash->notrace_hash))) {
+       if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) &&
+           ftrace_hash_empty(iter->hash)) {
                if (*pos > 0)
                        return t_hash_start(m, pos);
                iter->flags |= FTRACE_ITER_PRINTALL;
@@ -3442,7 +3435,8 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
                        ret = -ENOMEM;
                        goto out_unlock;
                }
-       }
+       } else
+               iter->hash = hash;
 
        if (file->f_mode & FMODE_READ) {
                iter->pg = ftrace_pages_start;
@@ -4526,6 +4520,9 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
                        free_ftrace_hash_rcu(old_hash);
                }
                mutex_unlock(&ftrace_lock);
+       } else {
+               /* For read only, the hash is the ops hash */
+               iter->hash = NULL;
        }
 
        mutex_unlock(&iter->ops->func_hash->regex_lock);