On Thu, Jan 20, 2011 at 05:22:02PM -0800, Yinghai Lu wrote: > On Wed, Jan 19, 2011 at 5:00 PM, Ram Pai <linuxram@xxxxxxxxxx> wrote: > > PCI: pre-allocate additional resources to devices only after successful > > allocation of essential resources. > > > > Linux tries to pre-allocate minimal resources to hotplug bridges. This > > works fine as long as there are enough resources to satisfy all other > > genuine resource requirements. However if enough resources are not > > available to satisfy any of these nice-to-have pre-allocations, the > > resource-allocator reports errors and returns failure. > > > > This patch distinguishes between must-have resource from nice-to-have > > resource. Any failure to allocate nice-to-have resources are ignored. > > > > This behavior can be particularly useful to trigger automatic > > reallocation when the OS discovers genuine allocation-conflicts > > or genuine unallocated-requests caused by buggy allocation behavior > > of the native BIOS/uEFI. > > > > https://bugzilla.kernel.org/show_bug.cgi?id=15960 captures the movitation > > behind the patch. > > > > changelog v2: o fixed a bug where pci_assign_resource() was called on a > > resource of zero resource size. > > > > changelog v3: addressed Bjorn's comment > > o "Please don't indent and right-justify the changelog". > > o removed add_size from struct resource. The additional > > size is now tracked using a linked list. > > > > changelog v4: o moved freeing up of elements of head list from > > assign_requested_resources_sorted() to > > __assign_resources_sorted(). This fixes a corruption bug. > > o removed a wrong reference to 'add_size' in > > pbus_size_mem(). Erroneously got introduced while > > generating the patch. > > o some code optimizations in adjust_resources_sorted() > > and assign_requested_resources_sorted() > > > > Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx> > > > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > > index 66cb8f4..efbdff2 100644 > > --- a/drivers/pci/setup-bus.c > > +++ b/drivers/pci/setup-bus.c > > @@ -33,11 +33,23 @@ struct resource_list_x { > > struct pci_dev *dev; > > resource_size_t start; > > resource_size_t end; > > + resource_size_t add_size; > > unsigned long flags; > > }; > > > > -static void add_to_failed_list(struct resource_list_x *head, > > - struct pci_dev *dev, struct resource *res) > > +#define free_list(type, head) do { \ > > + struct type *list, *tmp; \ > > + for (list = (head)->next; list;) { \ > > + tmp = list; \ > > + list = list->next; \ > > + kfree(tmp); \ > > + } \ > > + (head)->next = NULL; \ > > +} while (0) > > inline function should be better? I thought about it and decided to use the macro since the 'head' can be either a resouce_list_x pointer or a resouce_list pointer. A datastructure agonistic inline function would not be clean enough. RP > > Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
