[PATCH] fbcon: Use persistent allocation for cursor blinking

Every time the console cursor blinks, we do a kmalloc/kfree pair.  This
patch turns that into a single allocation.

This allocation was the most frequent kmalloc I saw on my test box.

[adaplas]
Per Alan's suggestion, move global variables to fbcon's private structure.
This would also avoid resource leaks when fbcon is unloaded.

Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 26 insertions, 10 deletions

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 1b4f75d1f8a9..050856e09e87 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -3225,7 +3225,10 @@ static void fbcon_exit(void)
                         module_put(info->fbops->owner);
 
                         if (info->fbcon_par) {
+                                struct fbcon_ops *ops = info->fbcon_par;
+
                                 fbcon_del_cursor_timer(info);
+                                kfree(ops->cursor_src);
                                 kfree(info->fbcon_par);
                                 info->fbcon_par = NULL;
                         }
diff --git a/drivers/video/console/fbcon.h b/drivers/video/console/fbcon.h
index f244ad066d68..b9386d168c04 100644
--- a/drivers/video/console/fbcon.h
+++ b/drivers/video/console/fbcon.h
@@ -80,6 +80,8 @@ struct fbcon_ops {
         char  *cursor_data;
         u8    *fontbuffer;
         u8    *fontdata;
+        u8    *cursor_src;
+        u32    cursor_size;
         u32    fd_size;
 };
     /*
diff --git a/drivers/video/console/softcursor.c b/drivers/video/console/softcursor.c
index 557c563e4aed..7d07d8383569 100644
--- a/drivers/video/console/softcursor.c
+++ b/drivers/video/console/softcursor.c
@@ -20,11 +20,12 @@
 
 int soft_cursor(struct fb_info *info, struct fb_cursor *cursor)
 {
+        struct fbcon_ops *ops = info->fbcon_par;
         unsigned int scan_align = info->pixmap.scan_align - 1;
         unsigned int buf_align = info->pixmap.buf_align - 1;
         unsigned int i, size, dsize, s_pitch, d_pitch;
         struct fb_image *image;
-        u8 *dst, *src;
+        u8 *dst;
 
         if (info->state != FBINFO_STATE_RUNNING)
                 return 0;
@@ -32,11 +33,19 @@ int soft_cursor(struct fb_info *info, struct fb_cursor *cursor)
         s_pitch = (cursor->image.width + 7) >> 3;
         dsize = s_pitch * cursor->image.height;
 
-        src = kmalloc(dsize + sizeof(struct fb_image), GFP_ATOMIC);
-        if (!src)
-                return -ENOMEM;
+        if (dsize + sizeof(struct fb_image) != ops->cursor_size) {
+                if (ops->cursor_src != NULL)
+                        kfree(ops->cursor_src);
+                ops->cursor_size = dsize + sizeof(struct fb_image);
 
-        image = (struct fb_image *) (src + dsize);
+                ops->cursor_src = kmalloc(ops->cursor_size, GFP_ATOMIC);
+                if (!ops->cursor_src) {
+                        ops->cursor_size = 0;
+                        return -ENOMEM;
+                }
+        }
+
+        image = (struct fb_image *) (ops->cursor_src + dsize);
         *image = cursor->image;
         d_pitch = (s_pitch + scan_align) & ~scan_align;
 
@@ -48,21 +57,23 @@ int soft_cursor(struct fb_info *info, struct fb_cursor *cursor)
                 switch (cursor->rop) {
                 case ROP_XOR:
                         for (i = 0; i < dsize; i++)
-                                src[i] = image->data[i] ^ cursor->mask[i];
+                                ops->cursor_src[i] = image->data[i] ^
+                                        cursor->mask[i];
                         break;
                 case ROP_COPY:
                 default:
                         for (i = 0; i < dsize; i++)
-                                src[i] = image->data[i] & cursor->mask[i];
+                                ops->cursor_src[i] = image->data[i] &
+                                        cursor->mask[i];
                         break;
                 }
         } else
-                memcpy(src, image->data, dsize);
+                memcpy(ops->cursor_src, image->data, dsize);
 
-        fb_pad_aligned_buffer(dst, d_pitch, src, s_pitch, image->height);
+        fb_pad_aligned_buffer(dst, d_pitch, ops->cursor_src, s_pitch,
+                              image->height);
         image->data = dst;
         info->fbops->fb_imageblit(info, image);
-        kfree(src);
         return 0;
 }