Re: [Qemu-devel] [SeaBIOS] [Seabios] [PATCH 0/6] 64bit PCI BARs allocations (take 2)

[Alexey Korolev <alexey.korolev@endace.com>]

On 06/03/12 02:49, Kevin O'Connor wrote:
> On Mon, Mar 05, 2012 at 10:53:25AM +0100, Gerd Hoffmann wrote:
>>> Given the churn in this area, I don't want to commit patches that do
>>> wholesale code replacement.  I'd prefer to see each patch
>>> independently add some functionality and perform its related cleanup.
>> Hardly doable, the algorithms are very different.
> I don't think that the algorithms are that different, and I don't
> think sending incremental patches is too difficult.
>
> Looking at Alexey's patches, it seems that "struct pci_region_entry"
> == "struct pci_device.bars" and "struct pci_region" == "struct
> pci_bus.r".  The pci_region_entry structs are dynamically allocated
> and put on lists, and the count/base arrays are replaced with list
> traversals.  The core multi-pass algorithm which finds the devices,
> extracts the bar info, determines the required bus sizing, and then
> assigns the bars does not appear to be fundamentally different.  I
> don't see why the data structures can't be converted in a series of
> incremental patches.  The only significant algo change (replacement of
> count/base arrays with list traversal) should be a relatively simple
> reviewable patch once the data structures have been modified.
Right, there is no point to make big functional changes, since
existing algorithms are same.
Note: pci_region_entry could be either pci_device.bar or pci_bridge.region.
>> Both approaches will work fine in the end.  I don't care much, I just
>> want something that works.  It's probably a bit risky to merge Alexey's
>> version before the planned mid-march release.
> FYI - the plan is to feature freeze in mid-march.
A question about lists, shall I move lists operation to header file and make use the list service
functions for PMM and Stack code or it will be applied later as a code "optimization"?