proc/stat: use defined macro KMALLOC_MAX_SIZE

There is a macro for the max size kmalloc can allocate, so use it instead
of a hardcoded number.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/proc/stat.c

@@ -138,9 +138,9 @@ static int stat_open(struct inode *inode, struct file *file)
 	struct seq_file *m;
 	int res;
 
-	/* don't ask for more than the kmalloc() max size, currently 128 KB */
-	if (size > 128 * 1024)
-		size = 128 * 1024;
+	/* don't ask for more than the kmalloc() max size */
+	if (size > KMALLOC_MAX_SIZE)
+		size = KMALLOC_MAX_SIZE;
 	buf = kmalloc(size, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;