From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755878AbZEYIpr (ORCPT ); Mon, 25 May 2009 04:45:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752542AbZEYIpi (ORCPT ); Mon, 25 May 2009 04:45:38 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:54535 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753289AbZEYIpi (ORCPT ); Mon, 25 May 2009 04:45:38 -0400 Message-ID: <4A1A5B02.6070605@cn.fujitsu.com> Date: Mon, 25 May 2009 16:46:58 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Ingo Molnar CC: Frederic Weisbecker , Steven Rostedt , LKML Subject: [PATCH 3/3] tracing/stat: do some cleanups References: <4A1A5AD1.3070804@cn.fujitsu.com> In-Reply-To: <4A1A5AD1.3070804@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org - remove duplicate code in stat_seq_init() - update comments to reflect the change from stat list to stat rbtree [ Impact: clean up ] Signed-off-by: Li Zefan --- kernel/trace/trace_stat.c | 56 +++++++++++++++++--------------------------- 1 files changed, 22 insertions(+), 34 deletions(-) diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index ed18701..abf2ba1 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -8,7 +8,6 @@ * */ - #include #include #include @@ -64,10 +63,15 @@ 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; while (*new) { struct stat_node *this; @@ -85,12 +89,13 @@ 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 on rightmost node + * of the tree. */ static int dummy_cmp(void *p1, void *p2) { @@ -98,15 +103,14 @@ 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; @@ -121,23 +125,13 @@ 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); @@ -146,22 +140,16 @@ 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; @@ -174,7 +162,7 @@ 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 */ @@ -252,7 +240,7 @@ 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) { -- 1.5.4.rc3