9 files changed, 302 insertions, 184 deletions

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 4888cb3fdef7..c7c83ff0f752 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -533,8 +533,7 @@ EXPORT_SYMBOL_GPL(debugfs_remove);
  */
 void debugfs_remove_recursive(struct dentry *dentry)
 {
-        struct dentry *child;
-        struct dentry *parent;
+        struct dentry *child, *next, *parent;
 
         if (IS_ERR_OR_NULL(dentry))
                 return;
@@ -544,61 +543,37 @@ void debugfs_remove_recursive(struct dentry *dentry)
                 return;
 
         parent = dentry;
+ down:
         mutex_lock(&parent->d_inode->i_mutex);
+        list_for_each_entry_safe(child, next, &parent->d_subdirs, d_u.d_child) {
+                if (!debugfs_positive(child))
+                        continue;
 
-        while (1) {
-                /*
-                 * When all dentries under "parent" has been removed,
-                 * walk up the tree until we reach our starting point.
-                 */
-                if (list_empty(&parent->d_subdirs)) {
-                        mutex_unlock(&parent->d_inode->i_mutex);
-                        if (parent == dentry)
-                                break;
-                        parent = parent->d_parent;
-                        mutex_lock(&parent->d_inode->i_mutex);
-                }
-                child = list_entry(parent->d_subdirs.next, struct dentry,
-                                d_u.d_child);
- next_sibling:
-
-                /*
-                 * If "child" isn't empty, walk down the tree and
-                 * remove all its descendants first.
-                 */
+                /* perhaps simple_empty(child) makes more sense */
                 if (!list_empty(&child->d_subdirs)) {
                         mutex_unlock(&parent->d_inode->i_mutex);
                         parent = child;
-                        mutex_lock(&parent->d_inode->i_mutex);
-                        continue;
+                        goto down;
                 }
-                __debugfs_remove(child, parent);
-                if (parent->d_subdirs.next == &child->d_u.d_child) {
-                        /*
-                         * Try the next sibling.
-                         */
-                        if (child->d_u.d_child.next != &parent->d_subdirs) {
-                                child = list_entry(child->d_u.d_child.next,
-                                                   struct dentry,
-                                                   d_u.d_child);
-                                goto next_sibling;
-                        }
-
-                        /*
-                         * Avoid infinite loop if we fail to remove
-                         * one dentry.
-                         */
-                        mutex_unlock(&parent->d_inode->i_mutex);
-                        break;
-                }
-                simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ up:
+                if (!__debugfs_remove(child, parent))
+                        simple_release_fs(&debugfs_mount, &debugfs_mount_count);
         }
 
-        parent = dentry->d_parent;
+        mutex_unlock(&parent->d_inode->i_mutex);
+        child = parent;
+        parent = parent->d_parent;
         mutex_lock(&parent->d_inode->i_mutex);
-        __debugfs_remove(dentry, parent);
+
+        if (child != dentry) {
+                next = list_entry(child->d_u.d_child.next, struct dentry,
+                                        d_u.d_child);
+                goto up;
+        }
+
+        if (!__debugfs_remove(child, parent))
+                simple_release_fs(&debugfs_mount, &debugfs_mount_count);
         mutex_unlock(&parent->d_inode->i_mutex);
-        simple_release_fs(&debugfs_mount, &debugfs_mount_count);
 }
 EXPORT_SYMBOL_GPL(debugfs_remove_recursive);
 
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 4372658c73ae..120d57a1c3a5 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -78,6 +78,11 @@ struct trace_iterator {
         /* trace_seq for __print_flags() and __print_symbolic() etc. */
         struct trace_seq        tmp_seq;
 
+        cpumask_var_t           started;
+
+        /* it's true when current open file is snapshot */
+        bool                    snapshot;
+
         /* The below is zeroed out in pipe_read */
         struct trace_seq        seq;
         struct trace_entry      *ent;
@@ -90,10 +95,7 @@ struct trace_iterator {
         loff_t                  pos;
         long                    idx;
 
-        cpumask_var_t           started;
-
-        /* it's true when current open file is snapshot */
-        bool                    snapshot;
+        /* All new field here will be zeroed out in pipe_read */
 };
 
 enum trace_iter_flags {
@@ -332,7 +334,7 @@ extern int trace_define_field(struct ftrace_event_call *call, const char *type,
                               const char *name, int offset, int size,
                               int is_signed, int filter_type);
 extern int trace_add_event_call(struct ftrace_event_call *call);
-extern void trace_remove_event_call(struct ftrace_event_call *call);
+extern int trace_remove_event_call(struct ftrace_event_call *call);
 
 #define is_signed_type(type)    (((type)(-1)) < (type)1)
 
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 3bef14c6586b..482ad2d84a32 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -629,7 +629,7 @@ extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
 static inline void tracing_start(void) { }
 static inline void tracing_stop(void) { }
 static inline void ftrace_off_permanent(void) { }
-static inline void trace_dump_stack(void) { }
+static inline void trace_dump_stack(int skip) { }
 
 static inline void tracing_on(void) { }
 static inline void tracing_off(void) { }
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8ce9eefc5bb4..a6d098c6df3f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2169,12 +2169,57 @@ static cycle_t		ftrace_update_time;
 static unsigned long    ftrace_update_cnt;
 unsigned long           ftrace_update_tot_cnt;
 
-static int ops_traces_mod(struct ftrace_ops *ops)
+static inline int ops_traces_mod(struct ftrace_ops *ops)
 {
-        struct ftrace_hash *hash;
+        /*
+         * Filter_hash being empty will default to trace module.
+         * But notrace hash requires a test of individual module functions.
+         */
+        return ftrace_hash_empty(ops->filter_hash) &&
+                ftrace_hash_empty(ops->notrace_hash);
+}
+
+/*
+ * Check if the current ops references the record.
+ *
+ * If the ops traces all functions, then it was already accounted for.
+ * If the ops does not trace the current record function, skip it.
+ * If the ops ignores the function via notrace filter, skip it.
+ */
+static inline bool
+ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
+{
+        /* If ops isn't enabled, ignore it */
+        if (!(ops->flags & FTRACE_OPS_FL_ENABLED))