| Message ID | 1369329099-8501-1-git-send-email-yinghai@kernel.org |
|---|---|
| State | Superseded |
| Headers | show |
On Thu, May 23, 2013 at 11:11 AM, Yinghai Lu <yinghai@kernel.org> wrote: > BenH reported that there is some assign unassigned resource problem > in powerpc. > > It turns out after > | commit 0c5be0cb0edfe3b5c4b62eac68aa2aa15ec681af > | Date: Thu Feb 23 19:23:29 2012 -0800 > | > | PCI: Retry on IORESOURCE_IO type allocations > > even the root bus does not have io port range, it will keep retrying > to realloc with mmio. > > Current retry logic is : try with must+optional at first, and if > it fails with any ioport or mmio, it will try must then try to extend > must with optional. > That will fail as mmio-non-pref and mmio-pref for bridge will > be next to each other. So we have no chance to extend mmio-non-pref. > > We can check fail type and only fall back for io port only, that will > keep mmio type still have must+optional. > > This will be become more often when we have x86 8 sockets or 32 sockets > system, and those system will have one root bus per socket. > They will have some root buses do not have ioport range. > > -v2: need to remove assigned entries from optional list too. > > Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com> > Signed-off-by: Yinghai Lu <yinghai@kernel.org> > > --- > drivers/pci/setup-bus.c | 23 +++++++++++++++++++++++ > 1 file changed, 23 insertions(+) > > Index: linux-2.6/drivers/pci/setup-bus.c > =================================================================== > --- linux-2.6.orig/drivers/pci/setup-bus.c > +++ linux-2.6/drivers/pci/setup-bus.c > @@ -317,6 +317,10 @@ static void __assign_resources_sorted(st > LIST_HEAD(local_fail_head); > struct pci_dev_resource *save_res; > struct pci_dev_resource *dev_res; > + unsigned long fail_type = 0; > + struct pci_dev_resource *fail_res; > + unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | > + IORESOURCE_PREFETCH; > > /* Check if optional add_size is there */ > if (!realloc_head || list_empty(realloc_head)) > @@ -348,6 +352,25 @@ static void __assign_resources_sorted(st > return; > } > > + /* check failed type */ > + list_for_each_entry(fail_res, &local_fail_head, list) > + fail_type |= fail_res->flags & type_mask; > + /* only io port fails */ > + if ((fail_type & type_mask) == IORESOURCE_IO) { > + struct pci_dev_resource *tmp_res; > + > + /* remove assigned non ioport from head list etc */ > + list_for_each_entry_safe(dev_res, tmp_res, head, list) > + if (dev_res->res->parent && > + !(dev_res->res->flags & IORESOURCE_IO)) { > + /* remove it from realloc_head list */ > + remove_from_list(realloc_head, dev_res->res); > + remove_from_list(&save_head, dev_res->res); > + list_del(&dev_res->list); > + kfree(dev_res); > + } > + } The problem we're trying to solve is that when allocation for type X fails, we retry allocation for type Y. This patch handles IO specially. I think it basically says, "if we only have IO allocation failures, don't retry MEM allocation." But a clean strategy would also avoid retrying IO allocation if we only had MEM allocation failures. Bjorn > free_list(&local_fail_head); > /* Release assigned resource */ > list_for_each_entry(dev_res, head, list) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, May 24, 2013 at 10:25 AM, Bjorn Helgaas <bhelgaas@google.com> wrote: > > The problem we're trying to solve is that when allocation for type X > fails, we retry allocation for type Y. > > This patch handles IO specially. I think it basically says, "if we > only have IO allocation failures, don't retry MEM allocation." But a > clean strategy would also avoid retrying IO allocation if we only had > MEM allocation failures. Well, that will make it little bit complicated as v3 that is sent in another mail. Need to separate ioport, mmio, mmio pref three types. Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux-2.6/drivers/pci/setup-bus.c =================================================================== --- linux-2.6.orig/drivers/pci/setup-bus.c +++ linux-2.6/drivers/pci/setup-bus.c @@ -317,6 +317,10 @@ static void __assign_resources_sorted(st LIST_HEAD(local_fail_head); struct pci_dev_resource *save_res; struct pci_dev_resource *dev_res; + unsigned long fail_type = 0; + struct pci_dev_resource *fail_res; + unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | + IORESOURCE_PREFETCH; /* Check if optional add_size is there */ if (!realloc_head || list_empty(realloc_head)) @@ -348,6 +352,25 @@ static void __assign_resources_sorted(st return; } + /* check failed type */ + list_for_each_entry(fail_res, &local_fail_head, list) + fail_type |= fail_res->flags & type_mask; + /* only io port fails */ + if ((fail_type & type_mask) == IORESOURCE_IO) { + struct pci_dev_resource *tmp_res; + + /* remove assigned non ioport from head list etc */ + list_for_each_entry_safe(dev_res, tmp_res, head, list) + if (dev_res->res->parent && + !(dev_res->res->flags & IORESOURCE_IO)) { + /* remove it from realloc_head list */ + remove_from_list(realloc_head, dev_res->res); + remove_from_list(&save_head, dev_res->res); + list_del(&dev_res->list); + kfree(dev_res); + } + } + free_list(&local_fail_head); /* Release assigned resource */ list_for_each_entry(dev_res, head, list)