[PATCH] resource allocator hole handling (simple and old)

[Stefan Reinauer]

See patch

[PATCH] resource allocator hole handling (simple and old)

[Myles Watson]

Index: src/devices/device.c
===================================================================
--- src/devices/device.c	(revision 4842)
+++ src/devices/device.c	(working copy)
@@ -576,7 +576,7 @@
    		continue;

/* Is it already outside the limits? */
-		if (res->size && (((res->base + res->size -1) < lim->base)
||
+		if (!res->size || (((res->base + res->size -1) < lim->base)
||
    			  (res->base > lim->limit)))
    		continue;

I think fixed resources of size 0 are broken.  I'd rather fix the targets.
It's hard for the allocator to avoid size 0 resources.

Thanks,
Myles

[Stefan Reinauer]

Myles Watson wrote:
> Index: src/devices/device.c
>
> --- src/devices/device.c	(revision 4842)
> +++ src/devices/device.c	(working copy)
> @@ -576,7 +576,7 @@
>    		continue;
> /* Is it already outside the limits? */
> if (res->size && (((res->base + res->size -1) < lim->base)
>
> ||
> if (!res->size || (((res->base + res->size -1) < lim->base)
>
> ||
>    			  (res->base > lim->limit)))
>    		continue;
>
> I think fixed resources of size 0 are broken.  I'd rather fix the targets.
> It's hard for the allocator to avoid size 0 resources.

Ok, this seems to be a left-over which came in through intelligent merging.

I checked the code and size 0 resources are skipped already..

if (!res->size) {
                        /* It makes no sense to have 0-sized, fixed
resources.*/
                        printk_err("skipping %s@%lx fixed resource,
size=0!\n",
                                   dev_path(dev), res->index);
                        continue;
                }

so generally that check for res->size could be dropped completely in
above construct, making it

/* Is it already outside the limits? */
-        if (res->size && (((res->base + res->size -1) < lim->base) ||
-                  (res->base > lim->limit)))
+        if (((res->base + res->size -1) < lim->base) || (res->base >
lim->limit))
             continue;

Stefan

[PATCH] resource allocator hole handling (simple and old)

[Myles Watson]

> I checked the code and size 0 resources are skipped already..

Yes, I should have remembered that.
> so generally that check for res->size could be dropped completely in
> above construct, making it
>      /* Is it already outside the limits? */
>    if (res->size && (((res->base + res->size -1) < lim->base) ||
>              (res->base > lim->limit)))
>    if (((res->base + res->size -1) < lim->base) || (res->base >
>
> lim->limit))
>              continue;

That could be done.  There's no functional difference as long as the check
for size 0 resources stays.

Thanks,
Myles