Messages in this thread Patch in this message | | | Date | Wed, 28 Dec 2005 20:29:15 -0500 | From | Dave Jones <> | Subject | Re: [POLL] SLAB : Are the 32 and 192 bytes caches really usefull on x86_64 machines ? |
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> Something like this: > > http://lwn.net/Articles/124374/
One thing that really sticks out like a sore thumb is soft_cursor() That thing gets called a *lot*, and every time it does a kmalloc/free pair that 99.9% of the time is going to be the same size alloc as it was the last time. This patch makes that alloc persistent (and does a realloc if the size changes). The only time it should change is if the font/resolution changes I think.
Boot tested with vesafb & fbconsole, which had the desired effect. With this patch, it almost falls off the profile.
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; } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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