Merge branch 'for-2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie...

[safe/jmp/linux-2.6] / kernel / trace / trace_stat.c

diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index e66f5e4..96cffb2 100644 (file)
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -10,6 +10,7 @@
 
 
 #include <linux/list.h>
+#include <linux/slab.h>
 #include <linux/rbtree.h>
 #include <linux/debugfs.h>
 #include "trace_stat.h"
@@ -49,7 +50,8 @@ static struct dentry          *stat_dir;
  * but it will at least advance closer to the next one
  * to be released.
  */
-static struct rb_node *release_next(struct rb_node *node)
+static struct rb_node *release_next(struct tracer_stat *ts,
+                                   struct rb_node *node)
 {
        struct stat_node *snode;
        struct rb_node *parent = rb_parent(node);
@@ -67,26 +69,35 @@ static struct rb_node *release_next(struct rb_node *node)
                        parent->rb_right = NULL;
 
                snode = container_of(node, struct stat_node, node);
+               if (ts->stat_release)
+                       ts->stat_release(snode->stat);
                kfree(snode);
 
                return parent;
        }
 }
 
-static void reset_stat_session(struct stat_session *session)
+static void __reset_stat_session(struct stat_session *session)
 {
        struct rb_node *node = session->stat_root.rb_node;
 
        while (node)
-               node = release_next(node);
+               node = release_next(session->ts, node);
 
        session->stat_root = RB_ROOT;
 }
 
+static void reset_stat_session(struct stat_session *session)
+{
+       mutex_lock(&session->stat_mutex);
+       __reset_stat_session(session);
+       mutex_unlock(&session->stat_mutex);
+}
+
 static void destroy_session(struct stat_session *session)
 {
        debugfs_remove(session->file);
-       reset_stat_session(session);
+       __reset_stat_session(session);
        mutex_destroy(&session->stat_mutex);
        kfree(session);
 }
@@ -150,7 +161,7 @@ static int stat_seq_init(struct stat_session *session)
        int i;
 
        mutex_lock(&session->stat_mutex);
-       reset_stat_session(session);
+       __reset_stat_session(session);
 
        if (!ts->stat_cmp)
                ts->stat_cmp = dummy_cmp;
@@ -183,7 +194,7 @@ exit:
        return ret;
 
 exit_free_rbtree:
-       reset_stat_session(session);
+       __reset_stat_session(session);
        mutex_unlock(&session->stat_mutex);
        return ret;
 }
@@ -193,17 +204,21 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
 {
        struct stat_session *session = s->private;
        struct rb_node *node;
+       int n = *pos;
        int i;
 
        /* Prevent from tracer switch or rbtree modification */
        mutex_lock(&session->stat_mutex);
 
        /* If we are in the beginning of the file, print the headers */
-       if (!*pos && session->ts->stat_headers)
-               return SEQ_START_TOKEN;
+       if (session->ts->stat_headers) {
+               if (n == 0)
+                       return SEQ_START_TOKEN;
+               n--;
+       }
 
        node = rb_first(&session->stat_root);
-       for (i = 0; node && i < *pos; i++)
+       for (i = 0; node && i < n; i++)
                node = rb_next(node);
 
        return node;
@@ -250,16 +265,21 @@ static const struct seq_operations trace_stat_seq_ops = {
 static int tracing_stat_open(struct inode *inode, struct file *file)
 {
        int ret;
-
+       struct seq_file *m;
        struct stat_session *session = inode->i_private;
 
+       ret = stat_seq_init(session);
+       if (ret)
+               return ret;
+
        ret = seq_open(file, &trace_stat_seq_ops);
-       if (!ret) {
-               struct seq_file *m = file->private_data;
-               m->private = session;
-               ret = stat_seq_init(session);
+       if (ret) {
+               reset_stat_session(session);
+               return ret;
        }
 
+       m = file->private_data;
+       m->private = session;
        return ret;
 }
 
@@ -270,11 +290,9 @@ static int tracing_stat_release(struct inode *i, struct file *f)
 {
        struct stat_session *session = i->i_private;
 
-       mutex_lock(&session->stat_mutex);
        reset_stat_session(session);
-       mutex_unlock(&session->stat_mutex);
 
-       return 0;
+       return seq_release(i, f);
 }
 
 static const struct file_operations tracing_stat_fops = {