use persistent allocation for cursor blinking.

Dave Jones
2006-08-01T18:56:26Z

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.

Signed-off-by: Dave Jones <davej@redhat.com>

--- linux-2.6.14/drivers/video/console/softcursor.c~ 2005-12-28 18:40:08.000000000 -0500
+++ linux-2.6.14/drivers/video/console/softcursor.c 2005-12-28 18:45:50.000000000 -0500
@@ -23,7 +23,9 @@ int soft_cursor(struct fb_info *info, st
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;
+ static u8 *src=NULL;
+ static int allocsize=0;

if (info->state != FBINFO_STATE_RUNNING)
return 0;
@@ -31,9 +33,15 @@ int soft_cursor(struct fb_info *info, st
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) != allocsize) {
+ if (src != NULL)
+ kfree(src);
+ allocsize = dsize + sizeof(struct fb_image);
+
+ src = kmalloc(allocsize, GFP_ATOMIC);
+ if (!src)
+ return -ENOMEM;
+ }

image = (struct fb_image *) (src + dsize);
*image = cursor->image;
@@ -61,7 +69,6 @@ int soft_cursor(struct fb_info *info, st
fb_pad_aligned_buffer(dst, d_pitch, src, s_pitch, image->height);
image->data = dst;
info->fbops->fb_imageblit(info, image);
- kfree(src);
return 0;
}

--