diff options
| -rw-r--r-- | kernel/trace/trace_stat.c | 54 |
1 files changed, 21 insertions, 33 deletions
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index 8030ec98dba..17f20ebdad2 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -93,10 +93,15 @@ static void destroy_session(struct stat_session *session) typedef int (*cmp_stat_t)(void *, void *); -static void -insert_stat(struct rb_root *root, struct stat_node *data, cmp_stat_t cmp) +static int insert_stat(struct rb_root *root, void *stat, cmp_stat_t cmp) { struct rb_node **new = &(root->rb_node), *parent = NULL; + struct stat_node *data; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + data->stat = stat; /* * Figure out where to put new node @@ -118,12 +123,13 @@ insert_stat(struct rb_root *root, struct stat_node *data, cmp_stat_t cmp) rb_link_node(&data->node, parent, new); rb_insert_color(&data->node, root); + return 0; } /* * For tracers that don't provide a stat_cmp callback. - * This one will force an immediate insertion on tail of - * the list. + * This one will force an insertion as right-most node + * in the rbtree. */ static int dummy_cmp(void *p1, void *p2) { @@ -131,15 +137,14 @@ static int dummy_cmp(void *p1, void *p2) } /* - * Initialize the stat list at each trace_stat file opening. + * Initialize the stat rbtree at each trace_stat file opening. * All of these copies and sorting are required on all opening * since the stats could have changed between two file sessions. */ static int stat_seq_init(struct stat_session *session) { struct tracer_stat *ts = session->ts; - struct stat_node *new_entry; - struct rb_root *root; + struct rb_root *root = &session->stat_root; void *stat; int ret = 0; int i; @@ -154,23 +159,12 @@ static int stat_seq_init(struct stat_session *session) if (!stat) goto exit; - /* - * The first entry. Actually this is the second, but the first - * one (the stat_list head) is pointless. - */ - new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); - if (!new_entry) { - ret = -ENOMEM; + ret = insert_stat(root, stat, ts->stat_cmp); + if (ret) goto exit; - } - root = &session->stat_root; - insert_stat(root, new_entry, dummy_cmp); - - new_entry->stat = stat; /* - * Iterate over the tracer stat entries and store them in a sorted - * list. + * Iterate over the tracer stat entries and store them in an rbtree. */ for (i = 1; ; i++) { stat = ts->stat_next(stat, i); @@ -179,22 +173,16 @@ static int stat_seq_init(struct stat_session *session) if (!stat) break; - new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); - if (!new_entry) { - ret = -ENOMEM; - goto exit_free_list; - } - - new_entry->stat = stat; - - insert_stat(root, new_entry, ts->stat_cmp); + ret = insert_stat(root, stat, ts->stat_cmp); + if (ret) + goto exit_free_rbtree; } exit: mutex_unlock(&session->stat_mutex); return ret; -exit_free_list: +exit_free_rbtree: reset_stat_session(session); mutex_unlock(&session->stat_mutex); return ret; @@ -207,7 +195,7 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos) struct rb_node *node; int i; - /* Prevent from tracer switch or stat_list modification */ + /* Prevent from tracer switch or rbtree modification */ mutex_lock(&session->stat_mutex); /* If we are in the beginning of the file, print the headers */ @@ -280,7 +268,7 @@ static int tracing_stat_open(struct inode *inode, struct file *file) } /* - * Avoid consuming memory with our now useless list. + * Avoid consuming memory with our now useless rbtree. */ static int tracing_stat_release(struct inode *i, struct file *f) { |