lkml.org 
[lkml]   [2009]   [May]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH 3/3] tracing/stat: do some cleanups
    - 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 <lizf@cn.fujitsu.com>
    ---
    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 <linux/list.h>
    #include <linux/rbtree.h>
    #include <linux/debugfs.h>
    @@ -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


    \
     
     \ /
      Last update: 2009-05-25 10:49    [W:0.028 / U:32.012 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site