Merge remote-tracking branch 'tip/core/rcu' into next.2012.09.25b

Resolved conflict in kernel/sched/core.c using Peter Zijlstra's
approach from https://lkml.org/lkml/2012/9/5/585.

1 files changed, 27 insertions, 49 deletions

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 2340f6978d6e..c5ca6ae5a30c 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -526,73 +526,51 @@ struct array_data {
         u32 elements;
 };
 
-static int u32_array_open(struct inode *inode, struct file *file)
-{
-        file->private_data = NULL;
-        return nonseekable_open(inode, file);
-}
-
-static size_t format_array(char *buf, size_t bufsize, const char *fmt,
-                           u32 *array, u32 array_size)
+static size_t u32_format_array(char *buf, size_t bufsize,
+                               u32 *array, int array_size)
 {
         size_t ret = 0;
-        u32 i;
 
-        for (i = 0; i < array_size; i++) {
+        while (--array_size >= 0) {
                 size_t len;
+                char term = array_size ? ' ' : '\n';
 
-                len = snprintf(buf, bufsize, fmt, array[i]);
-                len++;  /* ' ' or '\n' */
+                len = snprintf(buf, bufsize, "%u%c", *array++, term);
                 ret += len;
 
-                if (buf) {
-                        buf += len;
-                        bufsize -= len;
-                        buf[-1] = (i == array_size-1) ? '\n' : ' ';
-                }
+                buf += len;
+                bufsize -= len;
         }
-
-        ret++;          /* \0 */
-        if (buf)
-                *buf = '\0';
-
         return ret;
 }
 
-static char *format_array_alloc(const char *fmt, u32 *array,
-                                                u32 array_size)
+static int u32_array_open(struct inode *inode, struct file *file)
 {
-        size_t len = format_array(NULL, 0, fmt, array, array_size);
-        char *ret;
-
-        ret = kmalloc(len, GFP_KERNEL);
-        if (ret == NULL)
-                return NULL;
+        struct array_data *data = inode->i_private;
+        int size, elements = data->elements;
+        char *buf;
+
+        /*
+         * Max size:
+         *  - 10 digits + ' '/'\n' = 11 bytes per number
+         *  - terminating NUL character
+         */
+        size = elements*11;
+        buf = kmalloc(size+1, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+        buf[size] = 0;
+
+        file->private_data = buf;
+        u32_format_array(buf, size, data->array, data->elements);
 
-        format_array(ret, len, fmt, array, array_size);
-        return ret;
+        return nonseekable_open(inode, file);
 }
 
 static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
                               loff_t *ppos)
 {
-        struct inode *inode = file->f_path.dentry->d_inode;
-        struct array_data *data = inode->i_private;
-        size_t size;
-
-        if (*ppos == 0) {
-                if (file->private_data) {
-                        kfree(file->private_data);
-                        file->private_data = NULL;
-                }
-
-                file->private_data = format_array_alloc("%u", data->array,
-                                                              data->elements);
-        }
-
-        size = 0;
-        if (file->private_data)
-                size = strlen(file->private_data);
+        size_t size = strlen(file->private_data);
 
         return simple_read_from_buffer(buf, len, ppos,
                                         file->private_data, size);